JP2022096265A - Blade driving device - Google Patents

Abstract

To provide a blade driving device that can reduce backlash, is highly accurate, and can reduce noise.SOLUTION: A blade driving device comprises: an opening forming member that has an opening for passing light therethrough; a plurality of diaphragm blades that enter and exit from the opening of the opening forming member; a first rotating member that applies a driving force to the plurality of diaphragm blades; and a second rotating member that is arranged adjacent to the first rotating member. The first rotating member and the second rotating member are manufactured of a plastic film (PET film and the like). The first rotating member and the second rotating member are urged relative to each other.SELECTED DRAWING: Figure 9

Description

本発明は、一眼レフカメラなどに搭載する光量調節装置などの羽根駆動装置に関する。 The present invention relates to a blade driving device such as a light amount adjusting device mounted on a single-lens reflex camera or the like.

羽根駆動装置は、光路用の開口部を有する開口形成部材と、開口形成部材によって支持された回動部材と、回動部材の回転に連動し開口部を開閉する様に動く絞り羽根と、開口形成部材と固定される押さえ板と、押さえ板に取り付けられる駆動部と、駆動部に取り付けられるピニオンギアで構成される。 The blade drive device includes an opening forming member having an opening for an optical path, a rotating member supported by the opening forming member, a diaphragm blade that moves to open and close the opening in conjunction with the rotation of the rotating member, and an opening. It is composed of a holding plate fixed to the forming member, a drive unit attached to the holding plate, and a pinion gear attached to the drive unit.

回動部材は外周部にギアを有し、駆動部に取りけられたピニオンギアと係合するが、ギア係合部にはバックラッシが必ず存在する。従来の光量調節装置では、このバックラッシが絞りの精度に悪影響を与えるほか、ギア同士の衝突音が異音として問題になることがあった。 The rotating member has a gear on the outer peripheral portion and engages with the pinion gear attached to the drive portion, but the backlash always exists in the gear engaging portion. In the conventional light amount adjusting device, this backlash adversely affects the accuracy of the aperture, and the collision sound between the gears may become a problem as an abnormal noise.

特開２００９－５３４３４号公報Japanese Unexamined Patent Publication No. 2009-53434

特許文献１に記載の光量調節装置は、駆動リングのバックラッシを低減するために、２つの駆動リングを有しており、それぞれに設けられた歯部の位相が僅かにずれるように配置されたものである。しかしながら、この構成においては、歯部の位相がずれているだけであり、歯部の幅を大きくしたものと大差なく、ギア詰まりを起こして作動力が大きくなってしまう可能性がある。 The light amount adjusting device described in Patent Document 1 has two drive rings in order to reduce the backlash of the drive rings, and the tooth portions provided in the two drive rings are arranged so as to be slightly out of phase with each other. Is. However, in this configuration, only the phase of the tooth portion is out of phase, and there is a possibility that the gear is clogged and the operating force is increased, which is not much different from the one in which the width of the tooth portion is increased.

本発明に係る羽根駆動装置においては、上記を鑑み、
光を通過させる開口部を有する開口形成部材と、
前記開口形成部材の開口部を出入りする複数の絞り羽根と、
前記複数の絞り羽根に駆動力を与える第１の回動部材と、
前記光の光軸方向において前記第１の回動部材に隣接して配置された第２の回動部材と
を備え、
前記第１の回動部材と前記第２の回動部材は、前記開口部の周方向に対し逆方向に付勢されていることを特徴とする。 In view of the above, the blade drive device according to the present invention has.
An opening forming member having an opening through which light passes,
A plurality of diaphragm blades entering and exiting the opening of the opening forming member, and
A first rotating member that applies a driving force to the plurality of diaphragm blades,
A second rotating member arranged adjacent to the first rotating member in the optical axis direction of the light is provided.
The first rotating member and the second rotating member are urged in a direction opposite to the circumferential direction of the opening.

本発明によれば、作動力が大きくなることを防ぎつつ、省スペースで高精度かつ静音化を実現した羽根駆動装置を提供することが可能となる。 According to the present invention, it is possible to provide a blade drive device that realizes high accuracy and noise reduction in a space-saving manner while preventing an increase in operating force.

実施形態１に係る羽根駆動装置の分解斜視図。An exploded perspective view of the blade driving device according to the first embodiment. 実施形態１における開口形成部材の斜視図。The perspective view of the opening forming member in Embodiment 1. FIG. 実施形態１における絞り羽根の斜視図。The perspective view of the diaphragm blade in Embodiment 1. FIG. 実施形態１における第１の回動部材の斜視図。The perspective view of the 1st rotating member in Embodiment 1. FIG. 実施形態１における第２の回動部材の斜視図。The perspective view of the 2nd rotating member in Embodiment 1. FIG. 実施形態１における押さえ板の斜視図。The perspective view of the holding plate in Embodiment 1. FIG. 実施形態１における第１の回動部材と第２の回動部と付勢バネの関係図。FIG. 3 is a relationship diagram of a first rotating member, a second rotating portion, and an urging spring in the first embodiment. 実施形態１における第１の回動部材と第２の回動部材と絞り羽根の関係図。FIG. 3 is a relationship diagram of a first rotating member, a second rotating member, and a diaphragm blade in the first embodiment. 実施形態１における第１の回動部材と第２の回動部材とピニオンギアの関係図。FIG. 3 is a relationship diagram of a first rotating member, a second rotating member, and a pinion gear in the first embodiment. 実施形態２に係る羽根駆動装置の分解斜視図。An exploded perspective view of the blade driving device according to the second embodiment. 実施形態２における第１の回動部材と第２の回動部材の関係図。The relationship diagram of the 1st rotating member and the 2nd rotating member in Embodiment 2. FIG. 実施形態３に係る光量調節装置の分解斜視図。An exploded perspective view of the light amount adjusting device according to the third embodiment. 実施形態３に係る光量調節装置の断面図。FIG. 3 is a cross-sectional view of the light amount adjusting device according to the third embodiment. 実施形態３に係る光量調節装置の正面図。The front view of the light amount adjustment apparatus which concerns on Embodiment 3.

以下、本発明の実施形態について図面を参照しながら詳細に説明する。
＜実施形態１＞
図１は、本発明の実施形態１に係る光量調節装置である羽根駆動装置１０の分解斜視図である。羽根駆動装置１０は、光が通過する開口部３ａを有する開口形成部材３を有する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<Embodiment 1>
FIG. 1 is an exploded perspective view of a blade driving device 10 which is a light amount adjusting device according to the first embodiment of the present invention. The blade drive device 10 has an opening forming member 3 having an opening 3a through which light passes.

また、開口形成部材３の開口部３ａを通過する光を遮るように開口部３ａ内に出入りする複数の絞り羽根４が、開口部３ａの周囲を回動する第１の回動部材５と、第１の回動部材５に対し光軸方向で重なるように配置される第２の回動部材６とのそれぞれに対して係合している。なお、この第１の回動部材５と第２の回動部材６とは、ＰＥＴなどのフィルム部材（シート部材）によって形成されているが、樹脂などによって形成されていても良い。また、それぞれ、摺動塗装、遮光塗装、反射防止塗装などの表面処理が施されていることが好ましい。 Further, a plurality of diaphragm blades 4 that enter and exit the opening 3a so as to block the light passing through the opening 3a of the opening forming member 3 rotate around the opening 3a with the first rotating member 5. It is engaged with each of the second rotating members 6 arranged so as to overlap the first rotating member 5 in the optical axis direction. The first rotating member 5 and the second rotating member 6 are formed of a film member (sheet member) such as PET, but may be formed of resin or the like. Further, it is preferable that surface treatments such as sliding coating, light-shielding coating, and antireflection coating are applied to each.

カバー部材７が、絞り羽根４と第１の回動部材５と第２の回動部材６とを開口形成部材３との間に収容するように配置されており、カバー部材７にも開口形成部材３の開口部３ａと対応する位置に、開口部７ａが設けられている。また、駆動部１が開口形成部材３に取り付けられており、ピニオンギア２を介して駆動力を第１の回動部材５に伝達する。駆動部１として、ステッピングモータが用いられている。 The cover member 7 is arranged so as to accommodate the diaphragm blade 4, the first rotating member 5, and the second rotating member 6 between the opening forming member 3, and the cover member 7 also forms an opening. An opening 7a is provided at a position corresponding to the opening 3a of the member 3. Further, the driving unit 1 is attached to the opening forming member 3, and the driving force is transmitted to the first rotating member 5 via the pinion gear 2. A stepping motor is used as the drive unit 1.

図２には、開口形成部材３の拡大図を示す。開口形成部材３は光が通過する開口部３ａと、絞り羽根４と同数のカム溝３ｂを有する。 FIG. 2 shows an enlarged view of the opening forming member 3. The opening forming member 3 has an opening 3a through which light passes and a cam groove 3b having the same number as the diaphragm blades 4.

図３には、絞り羽根４の拡大図を示す。絞り羽根４は複数配置されているが基本的にはすべて同形状である。絞り羽根４には、第１の回動部材５側に係合ピン４ａ、開口形成部材３側に係合ピン４ｂが植設されている。係合ピン４ａが後述する第１の回動部材５の孔５ａと係合し、係合ピン４ｂが開口形成部材３のカム溝３ｂに係合しており、第１の回動部材５が開口部３ａの周囲を回動することに伴って、係合ピン４ｂがカム溝３ｂにガイドされて移動し、絞り羽根４が開口部３ａ内に進退する。絞り羽根４は、合成樹脂を基材とした本体に樹脂製の係合ピンをアウトサートする方法や、本体と係合ピンをモールド一体成型する方法が用いられて形成されている。なお、図１では絞り羽根は９枚用いられているが、本発明においてはこの限りでは無い。 FIG. 3 shows an enlarged view of the diaphragm blade 4. Although a plurality of diaphragm blades 4 are arranged, they basically all have the same shape. The diaphragm blade 4 is provided with an engaging pin 4a on the side of the first rotating member 5 and an engaging pin 4b on the side of the opening forming member 3. The engaging pin 4a is engaged with the hole 5a of the first rotating member 5 described later, the engaging pin 4b is engaged with the cam groove 3b of the opening forming member 3, and the first rotating member 5 is engaged. As the engagement pin 4b rotates around the opening 3a, the engagement pin 4b is guided by the cam groove 3b and moves, and the diaphragm blade 4 moves back and forth in the opening 3a. The diaphragm blade 4 is formed by using a method of outserting a resin engaging pin to a main body made of a synthetic resin as a base material or a method of integrally molding the main body and the engaging pin with a mold. Although nine diaphragm blades are used in FIG. 1, this is not the case in the present invention.

図４には、第１の回動部材５の拡大図を示す。第１の回動部材５は、絞り羽根４の係合ピン４ａと嵌合するための孔５ａと、後述する第２の回動部材６に設けられた当接部６ｂに当接して付勢力を及ぼす付勢部５ｂと、ピニオンギア２と係合し、駆動部１からの駆動力を受けるギア部５ｃを有する。 FIG. 4 shows an enlarged view of the first rotating member 5. The first rotating member 5 abuts on the hole 5a for fitting with the engaging pin 4a of the diaphragm blade 4 and the abutting portion 6b provided on the second rotating member 6, which will be described later, and has an urging force. It has a gear portion 5b that engages with the pinion gear 2 and receives a driving force from the driving portion 1.

図５には、第２の回動部材６の拡大図を示す。第２の回動部材６は、絞り羽根４の係合ピン４ａの径より一回り大きい孔６ａと、第１の回動部材５に設けられた付勢部５ｂに当接して付勢力を受ける当接部６ｂと、ピニオンギア２と係合し、駆動部１からの駆動力を受けるギア部６ｃを有する。 FIG. 5 shows an enlarged view of the second rotating member 6. The second rotating member 6 abuts on the hole 6a, which is one size larger than the diameter of the engaging pin 4a of the diaphragm blade 4, and the urging portion 5b provided on the first rotating member 5, and receives the urging force. It has a gear portion 6c that engages with the contact portion 6b and the pinion gear 2 and receives a driving force from the driving portion 1.

図６には、カバー部材７の拡大図を示す。カバー部材７は、上述した通り、絞り羽根４と第１の回動部材５と第２の回動部材６を間に挟みこむ形で開口形成部材３に取り付けられる。なお、第１の回動部材５、第２の回動部材６を貫通した絞り羽根４の係合ピン４ａが、カバー部材７の開口部７ａの内周部（内縁部）に摺接しながら回動する。 FIG. 6 shows an enlarged view of the cover member 7. As described above, the cover member 7 is attached to the opening forming member 3 so as to sandwich the diaphragm blade 4, the first rotating member 5, and the second rotating member 6 between them. The engaging pin 4a of the diaphragm blade 4 penetrating the first rotating member 5 and the second rotating member 6 rotates while sliding against the inner peripheral portion (inner edge portion) of the opening portion 7a of the cover member 7. Move.

図７は、第１の回動部材５と第２の回動部材６が光軸方向に重なった状態で、第１の回動部材５と第２の回動部材６が周方向に付勢力を及ぼし合っている状態を示している。第１の回動部材５の付勢部５ｂが第２の回動部材６の当接部６ｂに当接して周方向に付勢力を及ぼすことにより、第１の回動部材５と第２の回動部材６が相対的に周方向に付勢し合っている。 FIG. 7 shows a state in which the first rotating member 5 and the second rotating member 6 are overlapped in the optical axis direction, and the first rotating member 5 and the second rotating member 6 are urged in the circumferential direction. It shows the state of exerting each other. The urging portion 5b of the first rotating member 5 abuts on the abutting portion 6b of the second rotating member 6 and exerts an urging force in the circumferential direction, whereby the first rotating member 5 and the second rotating member 5 and the second The rotating members 6 are relatively urged in the circumferential direction.

具体的には、図７に示すように、付勢部５ｂは第１の回動部材５において光軸と直交する面に設けられて、光軸方向で第２の回動部材６側に立設されつつ、その先端が１８０度曲がった突起部である。この付勢部５ｂが第２の回動部材６において光軸と直交する面に立設された当接面を有する当接部６ｂに対して当接している。付勢部５ｂは、曲がった先端の復元力によって当接部６ｂに対する付勢力を及ぼしている。 Specifically, as shown in FIG. 7, the urging portion 5b is provided on the surface of the first rotating member 5 orthogonal to the optical axis, and stands on the second rotating member 6 side in the optical axis direction. It is a protrusion whose tip is bent 180 degrees while being installed. The urging portion 5b is in contact with the contact portion 6b having a contact surface erected on a surface orthogonal to the optical axis in the second rotating member 6. The urging portion 5b exerts an urging force on the contact portion 6b by the restoring force of the bent tip.

なお、付勢部５ｂは、第１の回動部材５が単体で存在する場合には真っすぐ延びるように設けられていて、第２の回動部材６を第１の回動部材５に重ねる際に、その先端が折り曲げられながら図７の状態となることによって、その復元力が上述した付勢力として働くように構成されていても良い。 The urging portion 5b is provided so as to extend straight when the first rotating member 5 is present alone, and when the second rotating member 6 is overlapped with the first rotating member 5. In addition, the restoring force may be configured to act as the above-mentioned urging force by bringing the tip into the state shown in FIG. 7 while being bent.

図８は、絞り羽根４が有する係合ピン４ａと、第１の回動部材５が有する孔５ａと、第２の回動部材６が有する孔６ａの関係を説明する拡大図である。第２の回動部材６が有する孔６ａを係合ピン４ａより一回り大きくすることで、絞り羽根４が有する係合ピン４ａは、第１の回動部材５が有する孔５ａとのみ嵌合することを特徴とする。なお、第１の回動部材５が有する孔５ａの方を一回り大きくし、係合ピン４ａは第２の回動部材６が有する孔６ａと嵌合する関係でも差し支えは無い。 FIG. 8 is an enlarged view illustrating the relationship between the engagement pin 4a of the diaphragm blade 4, the hole 5a of the first rotating member 5, and the hole 6a of the second rotating member 6. By making the hole 6a of the second rotating member 6 one size larger than the engaging pin 4a, the engaging pin 4a of the diaphragm blade 4 fits only with the hole 5a of the first rotating member 5. It is characterized by doing. It should be noted that there is no problem even if the hole 5a of the first rotating member 5 is made one size larger and the engaging pin 4a is fitted with the hole 6a of the second rotating member 6.

図９はピニオンギア２と、第１の回動部材５が有するギア５ｃと、第２の回動部材６が有するギア６ｃの関係を示す。ギア６ｃは周方向に付勢された状態でピニオンギアと当接するため、ピニオンギア２はギア５ｃとギア６ｃに常に挟まれた状態となり、バックラッシが低減されることを特徴とする。 FIG. 9 shows the relationship between the pinion gear 2, the gear 5c of the first rotating member 5, and the gear 6c of the second rotating member 6. Since the gear 6c comes into contact with the pinion gear in a state of being urged in the circumferential direction, the pinion gear 2 is always sandwiched between the gear 5c and the gear 6c, and the backlash is reduced.

なお、本実施形態においては、第１の回動部材５の付勢部５ｂが第２の回動部材６の当接部６ｂに当接して周方向に付勢力を及ぼすと説明したが、これは正確には各回動部材の回動方向（周方向）の接線方向へ付勢することを含んでいる。いずれの場合であっても本発明の作用にはほとんど影響することはなく、本実施形態における付勢部５ｂもその構造上、接線方向に付勢している。これに対し、付勢部５ｂによる付勢力によって移動する回動部材の移動方向をガイドするガイド部を形成することなどによって、付勢力が周方向に働くように構成しても良い。 In the present embodiment, it has been described that the urging portion 5b of the first rotating member 5 abuts on the abutting portion 6b of the second rotating member 6 to exert an urging force in the circumferential direction. To be precise, includes urging each rotating member in the tangential direction of the rotation direction (circumferential direction). In any case, the operation of the present invention is hardly affected, and the urging portion 5b in the present embodiment is tangentially urged due to its structure. On the other hand, the urging force may be configured to work in the circumferential direction by forming a guide portion that guides the moving direction of the rotating member that is moved by the urging force by the urging portion 5b.

＜実施形態２＞
以下、本発明の実施形態２に係る羽根駆動装置について説明する。なお、本実施形態は実施形態１と同じ構成を多く有しており、以下ではその相違点についてのみ説明する。なお、実施形態１の構成と対応する構成については同じ符号を用いて説明する。 <Embodiment 2>
Hereinafter, the blade driving device according to the second embodiment of the present invention will be described. It should be noted that this embodiment has many of the same configurations as those of the first embodiment, and only the differences thereof will be described below. The configuration corresponding to the configuration of the first embodiment will be described with reference to the same reference numerals.

図１０は、本実施形態の羽根駆動装置における分解斜視図を示している。実施形態１とは異なり、本実施形態における第２の回動部材６は、駆動部１のピニオンギア２と噛合するギア６ｃと、当接部６ｂがその基部に設けられており、周方向においてギア６ｃが設けられた部分のみで構成されている。また、孔６ａは設けられていない。 FIG. 10 shows an exploded perspective view of the blade driving device of the present embodiment. Unlike the first embodiment, the second rotating member 6 in the present embodiment is provided with a gear 6c that meshes with the pinion gear 2 of the drive unit 1 and a contact portion 6b at the base thereof, and is provided in the circumferential direction. It is composed of only the portion provided with the gear 6c. Further, the hole 6a is not provided.

図１１は、本実施形態の羽根駆動装置において、第１の回動部材５が有する付勢部５ｂと第２の回動部材６が有する当接部６ｂの関係を示す拡大図である。本実施形態における第２の回動部材６は、上述した通りその機能としてピニオンギア２と噛合するギア６ｃと当接部６ｂのみを有しており、概ね第１の回動部材５と同形状をしつつ、周方向においてはギア６ｃ付近のみに設けられている。この部分に対して当接部６ｂが形成されている。ギア６ｃ、当接部６ｂの形状としては、実施形態１と同様である。 FIG. 11 is an enlarged view showing the relationship between the urging portion 5b of the first rotating member 5 and the contact portion 6b of the second rotating member 6 in the blade driving device of the present embodiment. As described above, the second rotating member 6 in the present embodiment has only the gear 6c and the contact portion 6b that mesh with the pinion gear 2 as its functions, and has substantially the same shape as the first rotating member 5. In the circumferential direction, it is provided only in the vicinity of the gear 6c. A contact portion 6b is formed with respect to this portion. The shapes of the gear 6c and the contact portion 6b are the same as those in the first embodiment.

また、径方向においては、第１の回動部材５の孔５ａの位置よりも外側のみに第２の回動部材６が設けられている。これによって係合ピン４ａと第２の回動部材６との干渉を防いでいる。ただし、第２の回動部材６の内縁を第１の回動部材５の内縁と同等の位置となるように構成し、一部の係合ピン４ａが挿通される孔６ａを設けても良い。 Further, in the radial direction, the second rotating member 6 is provided only outside the position of the hole 5a of the first rotating member 5. This prevents the engagement pin 4a from interfering with the second rotating member 6. However, the inner edge of the second rotating member 6 may be configured to be at the same position as the inner edge of the first rotating member 5, and a hole 6a through which a part of the engaging pins 4a may be inserted may be provided. ..

このように、本実施形態においては、第２の回動部材６を周方向においてギア６ｃが設けられた部分のみで構成することにより、実施形態１と同様の効果を発揮しつつ、その構成を簡易にすることができる。 As described above, in the present embodiment, by configuring the second rotating member 6 only with the portion provided with the gear 6c in the circumferential direction, the configuration is realized while exhibiting the same effect as that of the first embodiment. It can be simplified.

また、上記実施形態では第１の回動部材５に弾性を持たせた付勢部５ｂを設け、付勢部５ｂを第２の回動部材６が有する当接部６ｂに突き当てるように構成したが、付勢部５ｂに代わり、当接部５ｂ’を設け、回動部材とは別に設けたコイルバネなどの付勢バネによって第１の回動部材５と第２の回動部材６との間に相対的に周方向に回動する方向もしくは回動部材の回動方向の接線方向に向けて付勢するように構成しても良い。その場合、第１の回動部材５と第２の回動部材６にはそれぞれ付勢バネが掛けられる係合部を有する。付勢バネであるコイルバネの一端を第１の回動部材５に、他端を第２の回動部材６に係合しても良いし、第１の付勢バネを第１の回動部材５と開口形成部材３やカバー部材７との間に掛け、第２の付勢バネを第２の回動部材６と開口形成部材３やカバー部材７との間に掛けても良い。 Further, in the above embodiment, the first rotating member 5 is provided with an elastic urging portion 5b, and the urging portion 5b is configured to abut against the abutting portion 6b of the second rotating member 6. However, instead of the urging portion 5b, a contact portion 5b'is provided, and the first rotating member 5 and the second rotating member 6 are provided by an urging spring such as a coil spring provided separately from the rotating member. In between, the spring may be configured to be urged in a direction that rotates relatively in the circumferential direction or in a tangential direction in the rotation direction of the rotating member. In that case, the first rotating member 5 and the second rotating member 6 each have an engaging portion on which an urging spring is applied. One end of the coil spring, which is an urging spring, may be engaged with the first rotating member 5, the other end may be engaged with the second rotating member 6, or the first urging spring may be engaged with the first rotating member. 5 may be hung between the opening forming member 3 and the cover member 7, and the second urging spring may be hung between the second rotating member 6 and the opening forming member 3 or the cover member 7.

また、上記実施形態においては、付勢部５ｂと当接部６ｂを回動部材に対し１組設ける構成について説明したが、これに限られず、周方向や径方向に並んで複数組設けても良い。この構成によれば、付勢部５ｂと当接部６ｂとの間で発生する付勢力と、ピニオンギア２からギア５ｃや６ｃに及びされる駆動力とによって、各回動部材が周方向への回転以外の方向へ付勢されることによる、第１の回動部材５と第２の回動部材６との重なり合いのズレの発生を低減することができる。 Further, in the above embodiment, the configuration in which one set of the urging portion 5b and the contact portion 6b is provided for the rotating member has been described, but the present invention is not limited to this, and a plurality of sets may be provided side by side in the circumferential direction or the radial direction. good. According to this configuration, the urging force generated between the urging portion 5b and the abutting portion 6b and the driving force applied from the pinion gear 2 to the gears 5c and 6c cause each rotating member to move in the circumferential direction. It is possible to reduce the occurrence of misalignment between the first rotating member 5 and the second rotating member 6 due to being urged in a direction other than rotation.

＜実施形態３＞
以下では、本発明の実施形態３に係る羽根駆動装置について説明する。本実施形態は、上記実施形態１、２において用いられる絞り羽根４を、すべて同じ羽根ではなく一部に異なる羽根を用いて構成することにより羽根駆動装置の薄型化を図るものである。なお、以下の説明において、上記実施形態の構成と対応する構成については同じ符号を用いて説明する。 <Embodiment 3>
Hereinafter, the blade driving device according to the third embodiment of the present invention will be described. In this embodiment, the diaphragm blades 4 used in the first and second embodiments are not all the same blades but are partially different blades to reduce the thickness of the blade drive device. In the following description, the configuration corresponding to the configuration of the above embodiment will be described using the same reference numerals.

図１２には、本実施形態に係る羽根駆動装置としての光量調節装置の分解斜視図を示している。図１２において、本実施形態では、絞り羽根４として９枚の絞り羽根を用いる場合について説明するが、本実施形態は、３枚以上の複数の絞り羽根（光量調節羽根）を使用する光量調節装置に適用することができる。絞り羽根４は、回動部材５の軸孔部５ｃに挿通されて回動中心軸となる第１軸部４ａおよび回動動作が案内される被駆動軸である第２軸部４ｂが互いに反対側の面に形成された基部と、基部から先端に向かって先細り形状に形成された羽根部４ｃとを有する。 FIG. 12 shows an exploded perspective view of the light amount adjusting device as the blade driving device according to the present embodiment. In FIG. 12, in the present embodiment, a case where nine diaphragm blades are used as the diaphragm blades 4 will be described, but in the present embodiment, a light amount adjusting device using a plurality of three or more diaphragm blades (light amount adjusting blades). Can be applied to. In the diaphragm blade 4, the first shaft portion 4a, which is inserted through the shaft hole portion 5c of the rotating member 5 and serves as the rotation center axis, and the second shaft portion 4b, which is the driven shaft to which the rotation operation is guided, are opposite to each other. It has a base portion formed on the side surface and a blade portion 4c formed in a tapered shape from the base portion toward the tip end.

絞り羽根４に駆動力を伝達する回動部材５はリング状に形成されている。該回動部材５の中央には開口部５ｄが形成されている。回動部材５には、その周方向の９箇所に形成された軸穴部５ａと、周方向の端部に５つ等間隔に設けられた突条部５ｅと、周方向端部の一部に形成されたギア部５ｃとを有する。また、回動部材５の周方向の１箇所には、反射部５ｆが設けられており、後述する位置センサ９により回動部材５の回転位相の検出に用いられる。 The rotating member 5 that transmits the driving force to the diaphragm blade 4 is formed in a ring shape. An opening 5d is formed in the center of the rotating member 5. The rotating member 5 includes shaft hole portions 5a formed at nine locations in the circumferential direction, ridge portions 5e provided at five equidistant ends in the circumferential direction, and a part of the circumferential end portions. It has a gear portion 5c formed in. Further, a reflective portion 5f is provided at one position in the circumferential direction of the rotating member 5, and is used for detecting the rotational phase of the rotating member 5 by a position sensor 9 described later.

また、本実施形態においては、絞り羽根４が回動する際に回動部材５とカバー部材７との段差に引っかからないようにするためのシート部材８が設けられている。 Further, in the present embodiment, a seat member 8 is provided so that the diaphragm blade 4 does not get caught in the step between the rotating member 5 and the cover member 7 when the diaphragm blade 4 rotates.

また、本実施形態においては、駆動部をカバー部材７に対して取り付けている。 Further, in the present embodiment, the drive unit is attached to the cover member 7.

また、カバー部材７に取り付けられた位置センサ９は、フォトリフレクタにより構成されている。位置センサ９の投光を回動部材５に形成された反射部５ｆが反射して位置センサ９の受光部が受光することにより、回動部材５がその初期位置にあることを検知することができる。ここにいう初期位置は、絞り羽根４によって形成される絞り開口の径（サイズ）が所定の開放開口径となる位置である。位置センサ９により検出された初期位置を基準として、駆動部であるステッピングモータ１に与える駆動パルス信号の数をカウントすることで、絞り開口径を制御し、光量を調節することができる。 Further, the position sensor 9 attached to the cover member 7 is composed of a photoreflector. It is possible to detect that the rotating member 5 is in its initial position by reflecting the light projected by the position sensor 9 by the reflecting portion 5f formed on the rotating member 5 and receiving the light received by the light receiving portion of the position sensor 9. can. The initial position referred to here is a position where the diameter (size) of the diaphragm opening formed by the diaphragm blade 4 becomes a predetermined open opening diameter. By counting the number of drive pulse signals given to the stepping motor 1 which is the drive unit with reference to the initial position detected by the position sensor 9, the aperture aperture diameter can be controlled and the amount of light can be adjusted.

回動部材５に形成された突条部５ｅは、突条部５ｅの外周面がカバー部材７の内周面７ｃに対して摺動することで、周方向（光軸回り方向）にて回転可能に支持される。 The ridge portion 5e formed on the rotating member 5 rotates in the circumferential direction (optical axis rotation direction) by sliding the outer peripheral surface of the ridge portion 5e with respect to the inner peripheral surface 7c of the cover member 7. Supported as possible.

また、９枚の絞り羽根４の第１軸部４ａはそれぞれ、回動部材５に形成された軸穴部５ａに回動可能に挿入される。一方、絞り羽根４の第２軸部４ｂはそれぞれ、開口形成部材３に形成されたカム溝３ｂに挿入される。 Further, the first shaft portion 4a of the nine diaphragm blades 4 is rotatably inserted into the shaft hole portion 5a formed in the rotating member 5, respectively. On the other hand, the second shaft portion 4b of the diaphragm blade 4 is inserted into the cam groove 3b formed in the opening forming member 3, respectively.

カバー部材７に固定されたステッピングモータ１が駆動されてピニオンギア２が回転すると、該ピニオンギア２にギア部５ｃが噛み合っている回動部材５も回転する。これにより、絞り羽根４は、第２軸部４ｂが開口形成部材３のカム溝３ｂに沿って移動し（すなわち、第２軸部４ｂがカム溝３ｂから駆動力を受けて）、第１軸部４ａを中心に回動する。 When the stepping motor 1 fixed to the cover member 7 is driven and the pinion gear 2 rotates, the rotating member 5 in which the gear portion 5c meshes with the pinion gear 2 also rotates. As a result, in the diaphragm blade 4, the second shaft portion 4b moves along the cam groove 3b of the opening forming member 3 (that is, the second shaft portion 4b receives a driving force from the cam groove 3b), and the first shaft portion 4b has a first shaft portion. It rotates around the portion 4a.

絞り羽根４は、周方向に等間隔で配置されており、それぞれの羽根部４ｃが他の絞り羽根の羽根部と重なり合うことで、それらの内側に光通過開口である絞り開口を形成する。そして、絞り羽根４が回動することで羽根部４ｃの重なり量が変化するとともに、絞り開口径が連続的に変更される。 The diaphragm blades 4 are arranged at equal intervals in the circumferential direction, and the respective blade portions 4c overlap with the blade portions of the other diaphragm blades to form a diaphragm opening which is a light passing opening inside them. Then, as the diaphragm blade 4 rotates, the amount of overlap of the blade portions 4c changes, and the diaphragm opening diameter is continuously changed.

図１３には、上記のように構成された光量調節装置を小絞りにした時の断面図を示す。ここで、絞り羽根４として、基材を薄いシート材で形成した絞り羽根４１を用いて光量調節装置を構成したとき、絞り羽根４１を重ね合わせた総厚は薄くなるため、図１３に示すスペースＨ１を狭くすることができる。そのため、ユニット自体を薄くすることが可能となる。また、小絞りになった時の絞り羽根４１の重なり量を抑えることで、図１３のスペースＨ２で示している開口形成部材３の上面からの突出量（編み上がり量）を抑えることができる。それにより、レンズなど近傍のユニットとの距離を詰めることができるため、カメラなど撮像装置自体の薄型化にも貢献できる。 FIG. 13 shows a cross-sectional view of the light amount adjusting device configured as described above when the aperture is reduced. Here, when the light amount adjusting device is configured by using the diaphragm blade 41 whose base material is formed of a thin sheet material as the diaphragm blade 4, the total thickness of the diaphragm blades 41 superposed on the diaphragm blade 41 becomes thin, so that the space shown in FIG. 13 is formed. H1 can be narrowed. Therefore, the unit itself can be made thinner. Further, by suppressing the amount of overlap of the diaphragm blades 41 when the diaphragm is made small, the amount of protrusion (knitting amount) from the upper surface of the opening forming member 3 shown by the space H2 in FIG. 13 can be suppressed. As a result, the distance from a nearby unit such as a lens can be reduced, which contributes to making the image pickup device itself such as a camera thinner.

しかしながら、全ての絞り羽根４を薄い基材で形成してしまうと剛性の低さから、絞り羽根４で形成する開口径が安定せず、絞りの特性面で不利となる。そこで、例えば図１４に示すカバー部材７と絞り羽根４とシート部材８のみを示す正面図において斜線部で示した３枚のみを剛性の高い基材の絞り羽根４２を使用すると剛性の高い絞り羽根４２が薄い基材の絞り羽根４１を支えることで、形成する開口径を安定させ、特性面を補うことができる。また、一部のみを変更するため、スペースＨ１、Ｈ２にも大きな影響を与えることなく実現することが可能となる。 However, if all the diaphragm blades 4 are formed of a thin base material, the opening diameter formed by the diaphragm blades 4 is not stable due to the low rigidity, which is disadvantageous in terms of diaphragm characteristics. Therefore, for example, in the front view showing only the cover member 7, the diaphragm blade 4, and the seat member 8 shown in FIG. 14, only the three diaphragm blades shown in the shaded area are the diaphragm blades 42 having a highly rigid base material. By supporting the diaphragm blade 41 of the thin base material, the 42 can stabilize the formed opening diameter and supplement the characteristic surface. Further, since only a part of the space is changed, it can be realized without significantly affecting the spaces H1 and H2.

以下、測定結果について説明する。以下のＡ－Ｃの３パターンで絞り羽根４を構成した場合に絞り特性を測定した結果を表１に示す。Ａ：９枚全てを６８μｍのポリエチレンテフタレート樹脂製のシート材であるカーボンフェザー（登録商標）を基材とした絞り羽根を使用、Ｂ；図１４の斜線となっている箇所の３枚を６８μｍのカーボンフェザーを基材とした絞り羽根を使用し、残りの６枚を５６μｍのカーボンフェザーを基材とした絞り羽根を使用、Ｃ：９枚全てを５６μｍのカーボンフェザーを基材とした絞り羽根を使用。なお、表中の単位として用いているＥＶは、絞り羽根４が口径を成す絞り開口の開口面積を表しており、それに対しどの程度ズレがあるかの指標を括弧書きで示している。すなわちＥＶ値が０に近い程、表に記載の特性において精度が良好（ズレがない）となることを意味し、一般的な光量調節装置における要求仕様を満たす程度である場合には「○」もしくは「◎」を付している。

The measurement results will be described below. Table 1 shows the results of measuring the diaphragm characteristics when the diaphragm blade 4 is configured with the following three patterns AC. A: All 9 sheets are made of 68 μm polyethylene teflate resin sheet material, carbon feather (registered trademark) is used as the base material, and B; 3 sheets in the shaded area in FIG. 14 are 68 μm. Use the diaphragm blades based on the carbon feathers of the above, the remaining 6 diaphragm blades using the 56 μm carbon feathers as the base material, and C: all 9 diaphragm blades based on the 56 μm carbon feathers. use. The EV used as a unit in the table represents the opening area of the diaphragm opening in which the diaphragm blade 4 forms the aperture, and the index of how much the diaphragm blade 4 deviates from the aperture is shown in parentheses. That is, the closer the EV value is to 0, the better the accuracy (no deviation) in the characteristics described in the table, and "○" when the EV value is sufficient to meet the required specifications in a general light amount adjusting device. Or, "◎" is attached.

最低作動電圧とは駆動部であるステッピングモータ１に印加する電圧の中で光量調節装置が規定の動作をする最も低い電圧値のことである。最低作動電圧について、Ａ、Ｂ、Ｃはほぼ同等で変化はなかった。 The minimum operating voltage is the lowest voltage value at which the light amount adjusting device operates in a specified manner among the voltages applied to the stepping motor 1 which is the driving unit. Regarding the minimum operating voltage, A, B, and C were almost the same and did not change.

最高速度とは駆動部であるステッピングモータ１に印加する電圧の中で光量調節装置が規定の動作をする最も速い駆動速度のことである。最高速度について、Ａ、Ｂ、Ｃはほぼ同等で変化はなかった。 The maximum speed is the fastest driving speed at which the light amount adjusting device operates in a specified manner among the voltages applied to the stepping motor 1 which is the driving unit. Regarding the maximum speed, A, B, and C were almost the same and there was no change.

繰り返し精度（キリムラ）とは特定の口径に対して複数回（今回の実験では１０回）絞り羽根の開閉を繰り返した時の口径の大きさのバラつきのことである。繰り返し精度の要求仕様は通常０．１ＥＶ以下程度であるのに対し、全て厚く剛性の高い６８μｍの絞り羽根を使用したＡは最大０．０７ＥＶであり、要求仕様を満足する。しかしながら、全てを５６μｍの絞り羽根を使用したＣは最大０．１３ＥＶであり、要求仕様を満足出来ない結果となった。一方、３枚を厚く剛性の高い６８μｍの絞り羽根、残りの６枚を５６μｍの絞り羽根を使用したＢは最大０．０６ＥＶであり、要求仕様を満足している。 The repeatability (Kirimura) is the variation in the size of the aperture when the aperture blades are opened and closed multiple times (10 times in this experiment) for a specific aperture. The required specifications for repeatability are usually about 0.1 EV or less, whereas A using all thick and highly rigid 68 μm diaphragm blades has a maximum of 0.07 EV, which satisfies the required specifications. However, C using all the diaphragm blades of 56 μm had a maximum of 0.13 EV, which did not satisfy the required specifications. On the other hand, B, which uses three thick and highly rigid diaphragm blades of 68 μm and the remaining six diaphragm blades of 56 μm, has a maximum of 0.06 EV, which satisfies the required specifications.

姿勢差とは通常カメラを構える向きを水平姿勢としたとき、その他の向き（姿勢）にした時の絞り値の差の最大値のことである。姿勢差の要求仕様は通常０．２５ＥＶ～０．３５ＥＶ程度である。Ａの最大姿勢差は０．１８２ＥＶと要求仕様を満足している。Ｂの最大姿勢差は０．１９６ＥＶ、Ｃの最大姿勢差は０．２１４ＥＶと全て要求仕様の範囲内であるが、絞り羽根を薄くするにしたがって悪化する傾向にあった。 The posture difference is the maximum value of the difference in the aperture value when the direction in which the camera is normally held is the horizontal posture and the other directions (postures) are set. The required specifications for the posture difference are usually about 0.25EV to 0.35EV. The maximum attitude difference of A is 0.182EV, which satisfies the required specifications. The maximum attitude difference of B was 0.196EV and the maximum attitude difference of C was 0.214EV, all within the required specifications, but they tended to worsen as the diaphragm blades were made thinner.

ヒスとはヒステリシスの略であり、この場合には絞り開口を絞り値Ｆ５．６に開いた状態から絞り値Ｆ１１相当まで閉じ、絞り値Ｆ１１相当に閉じた状態から絞り値Ｆ５．６に開く動作の前後の口径の大きさの差のことである。ヒステリシスは小絞りになるほど悪化する傾向にあり、この範囲における要求仕様は０．５ＥＶ程度である。Ａの最小絞り（Ｆ１１）のヒステリシスは０．３６ＥＶであった。Ｂは０．２９ＥＶ、Ｃは０．２１ＥＶと全て要求仕様内であるが、絞り羽根を薄くするにしたがって良化する傾向にある。 Hysteresis is an abbreviation for hysteresis. In this case, the operation of closing the aperture opening from the state where the aperture opening is set to the aperture value F5.6 to the aperture value F11 and opening the aperture opening from the state where the aperture value is equivalent to the aperture value F11 to the aperture value F5.6. It is the difference in the size of the caliber before and after. Hysteresis tends to worsen as the aperture becomes smaller, and the required specifications in this range are about 0.5 EV. The hysteresis of the minimum aperture (F11) of A was 0.36EV. B is 0.29EV and C is 0.21EV, which are all within the required specifications, but tend to improve as the diaphragm blades become thinner.

編み上がり量とは、上述したように小絞りになった時の絞り羽根の重なりにより絞り羽根が開口形成部材３の上面から突出した量（図１３のスペースＨ２）のことである。編み上がり量は通常、要求仕様で規定されることはないが、スペースの都合などにより、少ない方が望ましい。Ａの編み上がり量を基準とするとＢの編み上がり量は－０．１９ｍｍ、Ｃは－０．２５ｍｍと羽根を薄くするにしたがって少なくなる傾向にあった。 The knitting amount is an amount (space H2 in FIG. 13) in which the diaphragm blades protrude from the upper surface of the opening forming member 3 due to the overlap of the diaphragm blades when the diaphragm blades are made small as described above. The amount of knitting is usually not specified in the required specifications, but it is desirable that the amount is small due to space constraints. Based on the amount of knitting of A, the amount of knitting of B was -0.19 mm, and that of C was -0.25 mm, which tended to decrease as the blades were made thinner.

以上の結果から、本実施形態においては、Ｂのように、６枚の絞り羽根４１と３枚の絞り羽根４２とによって構成された絞り羽根の組み合わせにすることで、絞り特性を満足しつつ、編み上がり量を抑止することができる。 From the above results, in the present embodiment, by using a combination of the diaphragm blades composed of the six diaphragm blades 41 and the three diaphragm blades 42 as in B, the diaphragm blades are satisfied while satisfying the diaphragm characteristics. The amount of knitting can be suppressed.

以上説明した各実施例は代表的な例にすぎず、本発明の実施に際しては、各実施例に対して種々の変形や変更が可能である。例えば、表１において実際に作成した絞り羽根の測定結果を示したが、絞り羽根の基材として、カーボンフェザーではなくポリイミドなどの材料を用いても良い。 Each of the above-described embodiments is only a representative example, and various modifications and changes can be made to each embodiment when the present invention is implemented. For example, although the measurement results of the diaphragm blades actually prepared are shown in Table 1, a material such as polyimide may be used as the base material of the diaphragm blades instead of carbon feathers.

１ 駆動部
２ ピニオンギア
３ 開口形成部材
４ 絞り羽根
５ 第１の回動部材
５ｂ 付勢部
６ 第２の回動部材
６ｂ 当接部
７ カバー部材 1 Drive unit 2 Pinion gear 3 Aperture forming member 4 Aperture blade 5 First rotating member 5b Biasing unit 6 Second rotating member 6b Contact part 7 Cover member

Claims (5)

光を通過させる開口部を有する開口形成部材と、
前記開口形成部材の開口部を出入りする複数の絞り羽根と、
前記複数の絞り羽根に駆動力を与える第１の回動部材と、
前記光の光軸方向において前記第１の回動部材に隣接して配置された第２の回動部材と、
前記第１の回動部材および前記第２の回動部材のそれぞれに設けられたギア部に係合して駆動伝達するピニオンギアを有する駆動部と
を備え、
前記第１の回動部材と前記第２の回動部材は、相対的に前記開口部の周方向に対し回動する方向に付勢されていることを特徴とする羽根駆動装置。 An opening forming member having an opening through which light passes,
A plurality of diaphragm blades entering and exiting the opening of the opening forming member, and
A first rotating member that applies a driving force to the plurality of diaphragm blades,
A second rotating member arranged adjacent to the first rotating member in the optical axis direction of the light, and a second rotating member.
A drive unit having a pinion gear that engages with and transmits a gear unit provided in each of the first rotating member and the second rotating member is provided.
A blade driving device, wherein the first rotating member and the second rotating member are urged in a direction of relative rotation with respect to the circumferential direction of the opening. 前記第１の回動部材は、前記第１の回動部材に設けられた当接部を相対的に前記周方向に回転する方向に付勢する付勢部を有することを特徴とする請求項１に記載の羽根駆動装置。 The first rotating member is characterized by having an urging portion that urges a contact portion provided on the first rotating member in a direction in which the contact portion is relatively rotated in the circumferential direction. The blade drive device according to 1. 前記第１の回動部材には摺動塗装、遮光塗装、反射防止塗装などの表面処理が施されている請求項１または２に記載の羽根駆動装置。 The blade drive device according to claim 1 or 2, wherein the first rotating member is subjected to surface treatment such as sliding coating, light-shielding coating, and antireflection coating. 前記第１の回動部材と前記第２の回動部材はコイルバネで相対的に付勢され、前記第１の回動部材と前記第２の回動部材は、前記コイルバネが掛けられる係合部を有することを特徴とする請求項１から３のいずれか一項に記載の羽根駆動装置。 The first rotating member and the second rotating member are relatively urged by a coil spring, and the first rotating member and the second rotating member are engaged portions on which the coil spring is hooked. The blade drive device according to any one of claims 1 to 3, wherein the vane drive device comprises the above. 前記第１の回動部材と前記第２の回動部材は、同じ形状である請求項１から４のいずれか一項に記載の羽根駆動装置。 The blade driving device according to any one of claims 1 to 4, wherein the first rotating member and the second rotating member have the same shape.

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