JP2021056397A - Blade drive device - Google Patents

Abstract

To provide a blade drive device and imaging device that can adjust an amount of light down to a small diaphragm.SOLUTION: A blade drive device, which adjusts a size of an aperture light passes through by a plurality of blade members, comprises: an aperture formation member that forms an aperture part light passes through; a revolving member that revolves around the aperture part on one side of the aperture formation member in an optical axis direction; and a plurality of blade members that, by power of the revolving member being transmitted, get in and out of the aperture part and form a diaphragm aperture. The blade member has a cam pin that is inserted into a cam groove provided in the aperture formation member. In a process for forming a small diaphragm in the diaphragm aperture, in an area overlapping another cam groove through which the cam pin of another blade member is inserted in the optical axis direction, a tip part of a part traversing the other cam groove in the blade member moves while overlapping the other blade member in the optical axis direction.SELECTED DRAWING: Figure 8

Description

The present invention relates to a blade drive device such as a diaphragm device, for example.

Conventionally, as a blade driving device for driving a blade, a main plate having an opening for an optical path, a blade supported by the main plate and operating to open and close the opening, and a blade that rotates with respect to the main plate. Those provided with a drive ring are known (see Patent Document 1).

In such a blade driving device as in Patent Document 1, the blades are interlocked with a rotating drive ring, and the blades are operated so as to open and close an opening for an optical path.

Japanese Unexamined Patent Publication No. 2009-180921

In recent years, in a light amount adjusting device provided in a camera or the like, there is an increasing demand for a camera having a configuration in which a lens aperture is increased and even a bright lens can be stopped down to a smaller aperture.

When the aperture is configured to be smaller, the amount of rotation of the blades increases, and a part of the blades may get caught in the cam groove for guiding the aperture operation of the adjacent blades, which may hinder the aperture operation of the blades. It was.

In view of the above, the blade drive device according to the present invention is
A blade drive device that adjusts the size of the opening through which light passes by a plurality of blade members.
An opening forming member that forms an opening through which light passes,
A rotating member that rotates around the opening on one side of the opening forming member in the optical axis direction.
It is provided with a plurality of blade members that are transmitted with the power of the rotating member and enter and exit the opening to form a diaphragm opening.
The blade member has a cam pin inserted into a cam groove provided in the opening forming member.
In the process of forming a small diaphragm at the throttle opening, a portion of the blade member that crosses the other cam groove in a region that overlaps with the other cam groove through which the cam pin is inserted in the optical axis direction. A blade driving device characterized in that the tip portion moves while overlapping with the other blade member in the optical axis direction.

According to the present invention, it is possible to provide a blade driving device capable of narrowing a blade to a small diaphragm without causing an operation catch.

An exploded perspective view of the diaphragm device according to the embodiment of the present invention. FIG. 3 is a perspective view of a holding substrate used in the blade driving device according to the embodiment of the present invention. The perspective view of the drive ring used for the blade drive device which concerns on embodiment of this invention. FIG. 3 is a perspective view of a partition member used in the blade driving device according to the embodiment of the present invention. The perspective view of the diaphragm blade used in the blade drive device which concerns on embodiment of this invention. FIG. 3 is a perspective view of an opening forming member used in the blade driving device according to the embodiment of the present invention. The explanatory view of the intermediate diaphragm shape of the blade drive device which concerns on embodiment of this invention. An explanatory view of a small diaphragm shape of the blade driving device according to the embodiment of the present invention. Enlarged view of FIG.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an exploded perspective view of a diaphragm device 100 as a light amount adjusting device, which is an example of a blade driving device according to an embodiment of the present invention. The blade drive device of the present invention is mounted on an image pickup device such as a camera, and is used as a light amount adjusting device for adjusting the amount of light reaching the image pickup element.

As shown in FIG. 1, the drawing device 100 according to the present embodiment has a holding substrate 102 which is an opening forming member having an opening formed in the center. The holding substrate 102 is made by resin molding, but is not limited to this. A drive unit 101 is attached to the holding substrate 102. The drive unit 101 uses, for example, a stepping motor, a galvano motor, or the like. A pinion 104 is attached to the rotation shaft 101a of the drive unit 101. FIG. 2 is a perspective view of the holding substrate 102.

Further, the drawing device 100 has a drive ring 103 which is a rotating member that rotates around the opening on one surface of the holding substrate 102. FIG. 3 is a perspective view of the drive ring 103. The drive ring 103 is made by resin molding, but is not limited to this. The driving force is transmitted from the pinion 104 to the driving ring 103. The drive ring 103 is provided with an engaging hole, and the drive pin 106a, which is the engaging shaft of the diaphragm blade 106, which is a blade member, engages. That is, since the drive ring 103 is configured so that the diaphragm blades 106 move in and out of the light passage path as the drive ring 103 rotates, the member for driving the diaphragm blades 106 ( It becomes a power transmission member).

Further, it is preferable that the base portion 103a of the drive ring 103 is surface-treated on one side or both sides. Examples of surface treatments include sliding coating, antistatic treatment, antireflection treatment, and the like. By sliding coating, friction between the drive ring 103, the holding substrate 102, which is a sliding component, and the partition member 105, which will be described later, can be reduced, and power-saving operation becomes possible. In addition, by applying anti-reflection treatment, it is possible to suppress the reflection of light that has entered the main light intensity adjusting device and prevent the occurrence of ghosts, flares, etc. when the light intensity adjusting device is incorporated in the lens barrel. it can.

Further, the drive ring 103 is provided with a light-shielding portion 103d. The light-shielding portion 103d moves in and out of the slit of the photo interrupter 108 to act as a sensor for detecting the rotational position of the drive ring 103. It is used to detect the initial position of the light intensity control device.

FIG. 4 is a perspective view of the partition member 105. The partition member 105 has an opening in the center. The partition member 105 is defined in the radial direction with respect to the holding substrate 102 by engaging the engaging hole 105a of the partition member 105 with the engaging portion 102a of the holding substrate 102, and a plurality of protrusions of the opening forming member 107 described later. It is defined in the optical axis direction by being sandwiched by the plurality of protrusions 102b of the 107a and the holding substrate 102. In FIG. 2, a part of the protrusion 102b is indicated by a reference numeral. Since the partition member 105 can press the position where the cam pin 106b of the blade 106 is provided from the opposite side of the cam pin 106b, the cam pin 106b inserted into the cam groove 107b of the opening forming member 107, which will be described later, falls off from the cam groove 107b. You can prevent that.

Further, since the drive ring 103 is sandwiched between the partition member 105 and the rail portion 102c of the holding substrate 102, the drive ring 103 may have a minimum outer shape that can be sandwiched. Therefore, since the drive ring 103 can be miniaturized, the inertia during rotation is reduced, which is effective for high-speed drive. The partition member 105 is made by resin molding, but may be made by pressing a resin film (PET sheet material or the like), for example.

FIG. 5 is a perspective view of the diaphragm blade 106. A drive pin 106a and a cam pin 106b are provided on the blade portion 106h. The diaphragm blade 106 is integrally made of a blade portion 106h, a drive pin 106a, and a cam pin 106b by resin molding. For example, a PET sheet material or the like is pressed to create a blade portion 106h, and the drive pin 106a, The cam pin 106b may be created and attached by resin molding or the like.

Further, in this embodiment, the diaphragm blades are composed of nine diaphragm blades, but the number of diaphragm blades may be any number as long as it is two or more. In this embodiment, the diaphragm blade 106 will be described as an example, but other shutter blades, blades having an optical filter, and other blade drive devices to which various types are applied may be used. The maximum opening of the portion through which light passes may be defined by the opening of the opening forming member 107 or the holding substrate 102, or may be defined by the ends of the plurality of diaphragm blades 106.

Further, the PET sheet material or the like is press-processed to prepare the blade portion 106h from the sheet member which has been surface-treated such as light-shielding treatment, and the drive pin 106a and the cam pin 106b are produced by resin molding and adhered to the blade portion 106h. It may be integrated by welding, outsert molding, or the like. Further, the drive pin 106a and the cam pin 106b may be formed of a metal pin and integrated with the blade portion 106h by adhesion, welding, caulking or the like.

FIG. 6 is an opening forming member 107. The opening forming member 107 has a protrusion 107a as a plurality of support portions for supporting the partition member 105, and a plurality of cam grooves 107b. In FIG. 6, only a part of them is indicated by reference numerals. In the optical axis direction, the drive ring 103 drives in the space formed between the holding substrate 102 and the partition member 105, and the space formed between the partition member 105 and the opening forming member 107. , The diaphragm blade 106 is driven.

The drive pin 106a of the diaphragm blade 106 engages with the drive hole 103b of the drive ring 103. When the pinion 104 rotates and the driving force is transmitted to the driven portion 103c of the drive ring 103, the drive ring 103 rotates. When the drive ring 103 rotates, a driving force is applied to the drive pin 106a of the diaphragm blade 106 from the drive hole 103b of the drive ring 103, and the diaphragm blade 106 is driven. The cam pin 106b of the diaphragm blade 106 is engaged with the cam groove 107b formed in the opening forming member 107. Guided by the cam groove 107b, the diaphragm blade 106 moves in and out of the opening of the holding substrate 102. The diaphragm shape is adjusted by the plurality of diaphragm blades 106, and the amount of light passing through can be adjusted.

Next, regarding the drive ring 103, the support of the diaphragm blade 106 will be described. As shown in part in FIG. 7, the plurality of diaphragm blades 106 are uniformly arranged in the circumferential direction. In this embodiment, as shown in FIG. 7, the plurality of diaphragm blades 106 are interlocked by the rotation of the drive ring 103, and the size of the light passing opening can be changed.

Next, the overlapping of blades, which is a feature of this embodiment, will be described. The diaphragm device 100 of this embodiment is composed of nine diaphragm blades 106 as shown in FIG. 1, but all the diaphragm blades 106 have a symmetrical structure with the center of the diaphragm opening symmetrical. In the following description, only some diaphragm blades 106 are described, but the same applies to the other diaphragm blades 106. FIG. 7 shows a state in which only four diaphragm blades 106 are arranged on the opening forming member 107 in the diaphragm device 100 of this embodiment. The outer peripheral portion 106c provided around the drive pin 106a, which is the rotation center axis of the diaphragm blade 106, hangs to a position substantially equivalent to the cam groove 107b of the opening forming member 107 in the optical axis direction. FIG. 8 shows a state in which the aperture is further rotated in the aperture direction (small aperture direction). At this time, it can be seen that the outer peripheral portion 106c around the drive pin 106a, which is the rotation center axis of the diaphragm blade 106, crosses (crosses) the cam groove 107b.

However, since the outer peripheral portion 106c of the diaphragm blade 106 rides on the adjacent blade (overlaps in the optical axis direction), the diaphragm blade 106 does not interfere with the cam groove 107b. This will be described in detail with reference to FIG. FIG. 9 shows an enlarged view of FIG. It shows a state in which the apex portion 106d1 of the outer peripheral portion 106c1 of the diaphragm blade 1061 shown on the left side in FIG. 9 crosses directly above the cam groove 107b1 (the position where it overlaps with the cam groove 107b in the optical axis direction). In this state, according to the diaphragm blade 1062 shown on the right side in FIG. 9, the diaphragm blade 1061 is inserted under the apex portion 106d2 of the outer peripheral portion 106c2. The apex portion is the wall 107c (inner wall) on the inner peripheral side of the cam groove 107b or the outer circumference of the cam groove 107b when the diaphragm blade 106 rotates in the small diaphragm direction to form a diaphragm opening. It is described as meaning a portion that reaches the side wall 107d (outer wall).

FIG. 9 shows a state in which the apex portion 106d of the outer peripheral portion 106c of the diaphragm blade 106 crosses the cam groove 107b, but in a state where a diaphragm opening larger than this state is formed, the apex is directly above the cam groove 107b. The portion 106d is located. In this embodiment, at least in a state where the apex portion 106d is located directly above the cam groove 107b (the region where the apex portion 106d overlaps the cam groove 107b), between the outer peripheral portion 106c of the drawing blade 106 and the cam groove 107b. The outer peripheral portion 106c and the apex portion 106d are formed so that the throttle blade 106 moves while the adjacent blade is located on the side. By doing so, it is possible to prevent the tip end portion (apex portion 106d) of the diaphragm blade from abutting (colliding) with the wall 107d on the outer peripheral side of the cam groove 107b, and moving the blade beyond (straddling) the cam groove 107b. It is possible to squeeze to a smaller aperture than before.

That is, in this embodiment, in the operation of narrowing the diaphragm opening toward the small diaphragm state, the diaphragm blades are at least in a state where the outer peripheral portion 106c of the diaphragm blade 106 is located directly above the wall 107d on the outer peripheral side of the cam groove 107b. It is sufficient that the adjacent blades are located between the outer peripheral portion 106c of the 106 and the cam groove 107b.

Further, in the present embodiment, the outer peripheral portion 106c of the diaphragm blade 106 is integrally connected to the blade portion 106h which is a light-shielding portion, but the light-shielding portion and the drive pin 106a and the cam pin 106b formed by a separate member are integrally provided. It may be provided, or it may be provided as a separate member from them.

Further, in the present embodiment, the partition member 105 is provided at a position sandwiched by the plurality of protrusions 107a of the opening forming member 107 and the plurality of protrusions 102b of the holding substrate 102, but the drive ring 103 is provided by spreading it toward the outer shape. If possible, the partition member 105 may be omitted.

Further, in the present embodiment, as described above, the maximum opening of the portion through which light passes may be defined by the opening of the opening forming member 107 or the holding substrate 102, or may be defined by the ends of the plurality of diaphragm blades 106. You may. Other than that, it may be formed by a drive ring 103 or a partition member 105, or other members may be used. That is, any member including the opening forming member 107 may form an opening through which light passes, and is not limited to the one that forms the maximum opening of the aperture opening.

101 Drive unit 102 Holding substrate 103 Drive ring 104 Pinion 105 Partition member 106 Aperture blade 107 Aperture forming member 108 Photo interrupter

Claims (4)

A blade drive device that adjusts the size of the opening through which light passes by a plurality of blade members.
An opening forming member that forms an opening through which light passes,
A rotating member that rotates around the opening on one side of the opening forming member in the optical axis direction.
It is provided with a plurality of blade members that are transmitted with the power of the rotating member and enter and exit the opening to form a diaphragm opening.
The blade member has a cam pin inserted into a cam groove provided in the opening forming member.
In the process of forming a small diaphragm at the throttle opening, a portion of the blade member that crosses the other cam groove in a region that overlaps with the other cam groove through which the cam pin is inserted in the optical axis direction. A blade driving device characterized in that the tip portion moves while overlapping with the other blade member in the optical axis direction. The blade member has an engaging shaft that engages with an engaging hole provided in the rotating member.
The first aspect of claim 1, wherein the tip portion is provided around the engaging shaft and is an apex portion that first reaches the inner wall of the cam groove in the process of forming the throttle opening. Blade drive device. It has a partition member arranged between the blade member and the rotating member, and has a partition member.
The blade driving device according to claim 1 or 2, wherein the blade member is sandwiched between the opening forming member and the partition member. The blade driving device according to claim 2 or 3, wherein the blade member is provided with a light-shielding portion that blocks light, and the engaging shaft and the cam pin are provided as separate members.

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