WO2023168637A1

WO2023168637A1 - Aperture mechanism

Info

Publication number: WO2023168637A1
Application number: PCT/CN2022/080025
Authority: WO
Inventors: 宇野勝
Original assignee: 北京小米移动软件有限公司
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2023-09-14
Also published as: CN117043657A; JP2024513270A

Abstract

The objective of the present invention is to provide an aperture mechanism which is miniaturised in terms of structure for use in focusing and has a simple structure. An aperture mechanism (1) is provided with: a rotation driving portion (2), which is combined on a round-plate-shaped stator (21) and a rotor (22), which are opposite in an optical axis direction and are provided with through holes in the centre, with the rotor (22) rotating around the optical axis; an aperture driving portion (3), which is of a round plate shape which circumferentially rotates around the optical axis by means of the rotor (22) of the rotary driving portion (2), and has a through hole in the centre; an aperture portion (4), which has a plurality of aperture plates (41)-(41) which are engaged with the aperture driving portion (3) so as to move in a radial direction, wherein the area of an opening through which photography light passes can be enlarged and reduced as the plurality of aperture plates (41)-(41) move; and a guide plate (5), which restricts the direction of movement such that the plurality of aperture plates (41)-(41) respectively move in the radial direction.

Description

Aperture mechanism

Technical field

The present invention relates to an aperture mechanism for a smartphone built-in camera or a compact camera.

Background technique

As a prior art, for example, there is an aperture mechanism disclosed in Japanese Patent Application Laid-Open No. 2011-90028. In this prior art, since the aperture is operated by a lever, the structure is complicated.

Contents of the invention

Invent the problem to be solved

In view of the above problems, an object of the present invention is to provide an aperture mechanism that can downsize the structure used for focusing and has a simple structure.

solutions to problems

In one aspect of the present invention, the aperture mechanism is provided with: a rotation drive unit that combines a disc-shaped stator and a rotor that face each other in the optical axis direction and have a through hole in the center, and the rotor rotates around the optical axis; and the aperture a driving part, which is a disc shape having a through hole in the center, which is rotated in the circumferential direction of the optical axis by the rotor of the rotational driving part; and an aperture part, which is engaged with the aperture driving part to switch the aperture. a plurality of aperture plates that move in the radial direction by transmitting the rotational force of the drive unit, and can expand and reduce the opening area through which the shooting light passes as the plurality of aperture plates move; and a guide plate that limits the direction of movement, The plurality of aperture plates are moved along the radial direction respectively.

In addition, the radially inner end portion of each of the plurality of aperture plates is recessed into a V-shape, and the aperture portion is composed of three of the aperture plates provided at intervals of 60 degrees in the circumferential direction. The plurality of aperture plates are The plates move in the radial direction so as to partially overlap each other, and the opening shape of the aperture portion is a regular hexagon.

In addition, the surface of the aperture drive portion opposite to the aperture portion in the optical axis direction has a curved groove corresponding to the plurality of aperture plates, and each of the plurality of aperture plates has a protrusion that enters the curved groove. As the aperture drive unit rotates, the protrusion is guided in the curved groove, thereby allowing each of the plurality of aperture plates to move in the radial direction.

In addition, the stator has a combination of a yoke and a coil made of a magnetic material, and the rotor is configured such that a plurality of permanent magnets are arranged so that different magnetic poles are alternately exposed in the circumferential direction.

In addition, among the components constituting the aperture mechanism, a plurality of rotating bodies are interposed between a fixed member that does not rotate in the circumferential direction and a rotating member that rotates in the circumferential direction, and each of the plurality of rotating bodies is held on the fixed member. The circumferential fixed position of one of the components or the rotating member moves in the circumferential direction while rotating with respect to the other of the fixed member or the rotating member.

In addition, the outer shape of each of the plurality of rotating bodies is any one of a disc shape, a cylindrical shape, and a spherical shape.

In addition, the width dimension of each of the plurality of aperture plates is fixed, the guide plate has a recess of a fixed width with a central axis facing the radial direction, and each of the plurality of aperture plates is guided by a step provided in the recess. .

Description of the drawings

FIG. 1 schematically shows the structure of an aperture mechanism according to an embodiment of the present invention, and is an exploded perspective view in which each structural component is exploded and arranged in the optical axis direction.

FIG. 2 is a bottom view showing the surface of the diaphragm drive unit in the diaphragm mechanism on the side opposite to the diaphragm plate.

3 is a perspective view illustrating a state in which components are removed to expose the diaphragm portion of the diaphragm mechanism.

4 is a bottom view showing a combination of the aperture drive unit and the aperture plate in the aperture mechanism.

Detailed ways

The diaphragm mechanism 1 according to one embodiment of the present invention will be described with reference to the drawings. In the following description, “optical axis direction”, “circumferential direction”, “radial direction”, “radial inner” and “radial outer” refer to the overall direction of the aperture mechanism 1 unless otherwise specified. That is, the direction of rotation around the optical axis direction of the diaphragm mechanism 1 is the circumferential direction. Furthermore, the direction orthogonal to the optical axis direction is the radial direction.

Figure 1 shows an exploded view of the whole. The upper part of the figure is the direction toward the subject in the camera, and the lower part is the direction of the camera's imaging element. The part shown on the right side in FIG. 1 constitutes the diaphragm mechanism 1 of this embodiment. In FIG. 1 , the portion shown on the left is a lens driving mechanism X that receives imaging light focused by the aperture mechanism 1 . In addition, the lens driving mechanism X is not directly related to the present invention, and therefore will not be described in detail below. The aperture mechanism 1 is configured such that a rotation drive unit 2 , an aperture drive unit 3 , an aperture unit 4 , and a guide plate 5 are arranged in this order from the subject side toward the lens drive mechanism X, and are provided in a housing 6 . The housing 6 also serves as the housing of the lens drive mechanism X. One group or one lens 7 among the plurality of lenses constituting the camera is provided inside the housing 6 and in front of the rotation drive unit 2 (on the subject side).

The rotation drive unit 2 combines a stator 21 and a rotor 22 that are opposed to each other in the direction of the optical axis set in the camera, and the rotor 22 rotates around the optical axis, that is, in the circumferential direction. The rotor 22 may be configured to continuously rotate by a predetermined angle corresponding to the opening and closing of the aperture, or may be configured to rotate in multiple stages like a stepping motor. The stator 21 and the rotor 22 are disk-shaped (annular-shaped) having a through hole in the center through which imaging light (light corresponding to a subject input to an imaging element included in the camera) passes. The stator 21 has a combination of a yoke 211 and a coil 212 . The yoke 211 is formed of a magnetic material. In coil 212, passing electricity creates a magnetic field. In this embodiment, the coil 212 is integrated with a flexible printed circuit board (FPC) on which a circuit for operating the rotation drive unit 2 is formed. On the other hand, the rotor 22 is configured such that a plurality of permanent magnets 221 to 221 are arranged so that different magnetic poles are alternately exposed in the circumferential direction. Each of the plurality of permanent magnets 221 to 221 is in the shape of a fan-shaped flat plate in plan view, with one surface being an N pole and the other surface being an S pole. In the rotor 22 of this embodiment, the plurality of permanent magnets 221 to 221 are embedded and fixed in the frame 222 made of a non-magnetic material so that the magnetic poles are exposed at least on the surface facing the stator 21 . In this embodiment, the frame 222 is a part of the diaphragm driving unit 3 . According to Fleming's left-hand rule, the permanent magnets 221 of the rotor 22 attract and repel the magnetic field generated in the energized coil 212 according to the magnetic poles, as a result of which the rotor 22 rotates about the optical axis. When the aperture is stopped down and when the aperture is opened, the rotation direction of the rotor 22 is opposite. With the rotation drive unit 2 having such a structure, a rotation structure using magnetic force can be formed by the combination of the disc-shaped stator 21 and the rotor 22 . In this embodiment, there is no need to provide a member that moves in the optical axis direction when the rotor 22 rotates, and since the stator 21 and the rotor 22 are disk-shaped (annular), compact rotation in the optical axis direction can be achieved. Drive part 2.

The diaphragm drive unit 3 is a disc-shaped (annular) member having a through hole in the center, which is rotated in the circumferential direction by the rotor 22 of the rotation drive unit 2 . The through hole of the diaphragm drive unit 3 is configured to rotate without displacement by being fitted into a cylindrical portion (not shown) provided in the radial center of the housing 6 . The aperture driving part 3 is made of a non-magnetic material and is integrated with the rotor 22 of the rotation driving part 2 . Therefore, the diaphragm driving section 3 also rotates as the rotor 22 rotates. That is, the rotation drive unit 2 directly rotates the diaphragm drive unit 3 . Since the driving force transmission mechanism is not interposed between the rotational driving section 2 and the aperture driving section 3, the mechanism for rotating the aperture driving section 3 in response to the energization of the rotational driving section 2 can be made smaller (more compact) in the optical axis direction. Thin). The components that rotate in the diaphragm mechanism 1 of this embodiment are the rotor 22 and the diaphragm drive unit 3 . The diaphragm driving section 3 has a curved groove 31 corresponding to each diaphragm plate 41 on a surface facing the diaphragm section 4 in the optical axis direction (the surface opposite to the rotor 22 ). The width of the curved groove 31 is slightly larger than the diameter of the protrusion 411 of the aperture plate 41 . In addition, the bending groove 31 is provided at a position where the radial position of one end and the radial position of the other end are different within the movement range of the protrusion 411 of the aperture plate 41 . That is, the curved groove 31 is provided to intersect the circumferential direction of the diaphragm driving section 3 . In this embodiment, in order to move each aperture plate 41, three bending grooves 31 to 31 are formed in different ranges in the circumferential direction of the aperture driving section 3 corresponding to the three aperture plates 41 to 41. The three bending grooves 31 to 31 are formed in different ranges in the circumferential direction of the aperture driving section 3. The grooves 31 to 31 are formed into a cubic symmetrical shape (a shape that matches every 60 degrees in the circumferential direction) in the diaphragm driving section 3 . In the present embodiment, the curved groove 31 penetrates in the thickness direction of the aperture driving portion 3 , but it may be a bottomed groove that does not penetrate.

Among the components constituting the diaphragm mechanism 1 , a plurality of rotating bodies 8 to 8 are interposed between a fixed member that does not rotate in the circumferential direction and a rotating member that rotates in the circumferential direction. The fixed components in this embodiment are the housing 6, the stator 21 in the rotation driving part 2, and the guide plate 5. The rotating components in this embodiment are the rotor 22 in the rotation driving unit 2 and the aperture driving unit 3 . The rotating body 8 in this embodiment is a sphere. Each rotary body 8 is held at a fixed position in the circumferential direction of the fixed member. Specifically, a substantially semicircular notch 213 that is concave in the radial direction is formed on the outer edge of the stator 21 (the yoke 211 and the coil 212 ). The rotating body 8 is inserted into the notch 213 so that the rotating body 8 can rotate. The ground is supported on the stator 21. The plurality of rotating bodies 8 to 8 are also in contact with the inner surface of the housing 6 . Furthermore, each rotating body 8 moves in the circumferential direction while rotating relative to the outer peripheral portion of the diaphragm drive unit 3 among the rotating members. The outer peripheral portion of the diaphragm drive unit 3 where the plurality of rotating bodies 8 to 8 come into contact is flat. A groove extending in the circumferential direction so that the rotary body 8 can move may be formed on the outer peripheral portion of the diaphragm drive unit 3 . The plurality of rotating bodies 8 to 8 come into contact with the inner surface of the outer peripheral portion of the diaphragm driving section 3 and rotate, so that the diaphragm driving section 3 rotates in the circumferential direction at a fixed position in the optical axis direction. With this structure, the diaphragm driving section 3 can be stably rotated.

The aperture unit 4 has a plurality of aperture plates 41 to 41 . The plurality of aperture plates 41 to 41 are engaged with the aperture drive unit 3 to convert and transmit the rotational force of the aperture drive unit 3 , thereby moving in the radial direction. The movement of the aperture plates 41 to 41 can expand and reduce the opening area through which the photographing light passes. Each diaphragm plate 41 has a flat plate shape, and its length along the radial direction of the diaphragm mechanism 1 is larger than its width along the circumferential direction of the diaphragm mechanism 1 . The width dimension of each aperture plate 41 is fixed. Therefore, each aperture plate 41 has a rectangular area. The radially inner end portion of each aperture plate 41 is symmetrical in the width direction and is formed into a V-shaped depression in the radially outer direction. The aperture unit 4 is composed of three aperture plates 41 to 41 arranged at intervals of 60 degrees in the circumferential direction. The plurality of aperture plates 41 to 41 move in the radial direction so as to partially overlap each other. Therefore, the opening shape of the aperture unit 4 is substantially a regular hexagonal shape. In addition, in each aperture plate 41, the plate thickness of the portion overlapping with other aperture plates 41 is formed to be small. For example, it can be half the thickness of the other parts. Accordingly, even if the plurality of aperture plates 41 to 41 partially overlap, each aperture plate 41 can move smoothly. In the diaphragm unit 4 configured in this way, the radially inner end portion of each diaphragm plate 41 is recessed into a V-shape, and the opening shape of the diaphragm unit 4 is substantially a regular hexagonal shape. Therefore, it can be adjusted according to the camera itself or the camera-mounted The aperture value set by the control unit of the device (smartphone, etc.) expands and contracts the opening area through which the shooting light passes in the three aperture plates 41 to 41 .

Each aperture plate 41 has a protrusion 411 that enters the curved groove 31 at an outer diameter portion. The protrusion 411 may be formed by, for example, a rod-shaped body (a round rod in this embodiment) penetrating the main body of each aperture plate 41 . The protrusion size of the protrusion 411 is smaller than the depth size of the curved groove 31 of the diaphragm driving part 3 . This protrusion 411 is fitted into the curved groove 31 of the diaphragm driving part 3 . Therefore, as the aperture driving section 3 rotates (arrow R in FIG. 4 ), the protrusion 411 is guided in the curved groove 31 , and each aperture plate 41 moves in the radial direction (arrow M in FIG. 4 ). According to this structure, there is no need to provide a member that moves along the optical axis direction, and the plurality of aperture plates 41 to 41 are moved in the radial direction by converting and transmitting the rotational force of the aperture driving unit 3 . Since each diaphragm plate 41 is directly moved by the rotation of the diaphragm drive unit 3, the time delay during focusing can be minimized.

The guide plate 5 restricts the movement direction so that each aperture plate 41 moves in the radial direction. The guide plate 5 has a recessed portion 51 with a fixed width whose central axis faces the radial direction. Both ends of the recess 51 in the width direction are steps 511 extending in the linear direction. The aperture plate 41 moves in the radial direction while being in contact with the step 511 . That is, the step 511 provided in the recessed portion 51 guides each aperture plate 41 . With the guide plate 5 having such a structure, each aperture plate 41 can be moved in the radial direction with a simple structure. In the guide portion of this embodiment, a groove 512 extending in the radial direction into which the protrusion 411 of each aperture plate 41 enters is formed in the recessed portion 51 .

As described above, in this embodiment, the diaphragm mechanism 1 is provided with a rotation drive unit 2 that combines a disk-shaped stator 21 and a rotor 22 that face each other in the optical axis direction and have a through hole in the center, and the above-mentioned The rotor 22 rotates around the optical axis; the aperture driving part 3 is a disc shape with a through hole in the center, which is rotated in the circumferential direction of the optical axis by the rotor 22 of the rotation driving part 2; the aperture part 4 has The plurality of aperture plates 41 to 41 are engaged with the aperture driving part 3 to convert and transmit the rotational force of the aperture driving part to move in the radial direction. As the aperture plates 41 to 41 move, they can The opening area through which the photographing light passes is enlarged and reduced; and the guide plate 5 restricts the movement direction so that the plurality of aperture plates 41 to 41 move along the radial direction respectively.

According to this structure, the diaphragm mechanism 1 is constructed by combining the rotational driving part 2 composed of the disc-shaped stator 21 and the rotor 22 , the disc-shaped aperture driving part 3 , the aperture plate 41 and the guide plate 5 . Therefore, with the structure for enlarging and reducing the opening area through which imaging light passes, the size in the optical axis direction can be minimized.

In addition, the radially inner end portion of each of the plurality of aperture plates 41 to 41 is recessed into a V-shape, and the aperture portion 4 is composed of three aperture plates 41 arranged at intervals of 60 degrees in the circumferential direction. The plurality of aperture plates 41 to 41 move in the radial direction so as to partially overlap each other, and the opening shape of the aperture portion 4 is a regular hexagon.

According to this structure, the radially inner end portion of each of the plurality of diaphragm plates 41 to 41 is recessed into a V-shape. By setting the opening shape of the diaphragm portion 4 to a regular hexagonal shape, it is possible to expand and contract in three areas. The opening area of the aperture plates 41 to 41 through which imaging light passes.

In addition, the surface of the aperture driving portion 3 facing the aperture portion 4 in the optical axis direction has a curved groove 31 corresponding to the plurality of aperture plates 41 to 41. Each of the plurality of aperture plates 41 to 41 There is a protrusion 411 that enters the bending groove 31. As the aperture driving part 3 rotates, the protrusion 411 is guided in the bending groove 31, so that each of the plurality of aperture plates 41 to 41 can be moved along the above-mentioned bending groove 31. Radial movement.

According to this structure, the plurality of aperture plates 41 to 41 can be moved in the radial direction without providing a member that moves in the optical axis direction.

The stator 21 has a combination of a yoke 211 made of a magnetic material and a coil 212. The rotor 22 is configured such that a plurality of permanent magnets 221 to 221 are arranged so that different magnetic poles are alternately exposed in the circumferential direction.

According to this structure, a rotation structure utilizing magnetic force can be formed by combining the disc-shaped stator 21 and the rotor 22 .

In addition, among the components constituting the aperture mechanism 1, a plurality of rotating bodies 8 to 8 are interposed between a fixed member that does not rotate in the circumferential direction and a rotating member that rotates in the circumferential direction. Among the plurality of rotating bodies 8 to 8 Each of them is held at a fixed position in the circumferential direction of one of the fixed member or the rotating member, and moves in the circumferential direction while rotating relative to the other of the fixed member or the rotating member.

According to this structure, the diaphragm driving section 3 can be stably rotated by the rotating body 8 interposed between the fixed member and the rotating member.

In addition, the outer shape of each of the plurality of rotating bodies 8 to 8 may be any one of a disc shape, a cylindrical shape, and a spherical shape.

According to this configuration, the diaphragm drive unit 3 can be rotated by the rotating body 8 having a simple shape.

In addition, the width dimension of each of the plurality of aperture plates 41 to 41 is fixed, and the guide plate 5 has a recess 51 of a fixed width with a central axis oriented in the radial direction. It is guided by the step 511 provided in the recessed portion 51 .

According to this structure, each of the plurality of diaphragm plates 41 to 41 can be moved in the radial direction with a simple structure.

The diaphragm mechanism 1 of this embodiment configured as above is configured by combining the rotational driving part 2 composed of the disk-shaped stator 21 and the rotor 22 , the disk-shaped diaphragm driving part 3 , the diaphragm plate 41 and the guide plate 5 Aperture mechanism 1. Therefore, with regard to the structure for enlarging and reducing the opening area through which imaging light passes, the size in the optical axis direction can be minimized. Therefore, it is possible to provide the diaphragm mechanism 1 which can downsize the structure used for focusing and has a simple structure.

The present embodiment has been described above. However, the present invention is not limited to the above-mentioned embodiment, and appropriate design changes can be made within the scope of the present invention. In addition, the functions and effects of the present invention are not limited to the above-described embodiment. That is, the embodiments disclosed this time are exemplary in every respect and do not limit the present invention. The scope of the present invention is defined by the scope of the claims rather than the above description. In addition, the scope of the present invention is intended to include all changes within the meanings equivalent to the claims and within the scope.

For example, the diaphragm unit 4 in the above embodiment is composed of three diaphragm plates 41 to 41 . However, the number of aperture plates 41 may be two, or four or more. In addition, in the diaphragm unit 4 of the above-described embodiment, the opening shape is substantially a regular hexagonal shape, but it may be formed into various shapes according to the number of the diaphragm plates 41 .

In addition, each outer shape of the rotating body 8 is spherical in the above-mentioned embodiment. However, the outer shape is not limited to this, as long as it is a shape that can be rotated so that the rotation center does not fluctuate in the optical axis direction, for example, it may be a disc shape or a cylindrical shape. By making the rotary body 8 have a spherical shape, a disc shape, or a cylindrical shape as in the above-mentioned embodiment, the diaphragm drive unit 3 can be rotated by the rotary body 8 having a simple shape. In addition, when the rotating body 8 is disk-shaped or cylindrical, the extending direction of the rotation center coincides with the radial direction of the diaphragm mechanism 1 . In addition, the rotating body 8 may be integrated into the aperture mechanism 1 with a bearing unit. In this case, the rotating body 8 is a component of the bearing unit (in the case of a ball bearing, it is a ball built into the bearing unit).

In addition, in the above-described embodiment, each rotary body 8 is held at a fixed position in the circumferential direction of the fixed member, and is configured to move in the circumferential direction while rotating relative to the rotary member. However, on the contrary, each rotary body 8 may be held at a fixed position in the circumferential direction of the rotating member, and may be configured to move in the circumferential direction while rotating relative to the fixed member.

Explanation of reference symbols:

1 aperture mechanism

2 Rotary drive unit

21 stator

211 yoke

212 coil

213 notch

22 rotors

221 permanent magnet

222 frame

3 aperture drive unit

31 curved slot

4 aperture section

41 aperture plate

411Protrusion

5 guide plate

51 recess

511 steps

512 slots

6 shells

7 lenses

8 rotating bodies

X lens drive mechanism

RRotation direction of aperture drive unit

M aperture plate movement direction

Claims

An aperture mechanism is characterized by having:

A rotary drive unit that combines a disk-shaped stator and a rotor that are opposed in the optical axis direction and have a through hole in the center, and the rotor rotates around the optical axis;

an aperture driving part, which is a disc shape with a through hole in the center and is rotated in the circumferential direction of the optical axis by the rotor of the rotation driving part;

The aperture unit has a plurality of aperture plates that are engaged with the aperture drive unit to convert and transmit the rotational force of the aperture drive unit to move in the radial direction. As the plurality of aperture plates move, Ability to expand and contract the opening area through which shooting light passes; and

a guide plate that limits the movement direction so that the plurality of aperture plates move along the radial direction respectively.
The aperture mechanism according to claim 1, wherein

A radially inner end portion of each of the plurality of aperture plates is recessed into a V-shape,

The aperture section is composed of three aperture plates arranged at intervals of 60 degrees in the circumferential direction, and the plurality of aperture plates move along the radial direction in a manner that partially overlaps each other,

The opening shape of the aperture portion is a regular hexagonal shape.
The aperture mechanism according to claim 1 or 2, wherein,

The surface of the diaphragm driving part opposite to the diaphragm part in the optical axis direction has curved grooves respectively corresponding to the plurality of diaphragm plates,

Each of the plurality of aperture plates has a protrusion entering the curved groove,

As the aperture driving part rotates, the protrusion is guided in the curved groove, thereby enabling each of the plurality of aperture plates to move in the radial direction.
The aperture mechanism according to any one of claims 1 to 3, wherein:

The stator has a combination of a yoke and a coil formed of a magnetic body,

The rotor is configured such that a plurality of permanent magnets are arranged in such a manner that different magnetic poles are alternately exposed in the circumferential direction.
The aperture mechanism according to any one of claims 1 to 4, wherein

Among the components constituting the aperture mechanism, a plurality of rotating bodies are interposed between a fixed member that does not rotate in the circumferential direction and a rotating member that rotates in the circumferential direction.

Each of the plurality of rotating bodies is maintained at a fixed position in the circumferential direction of one of the fixed component or the rotating component, and rotates with respect to the other one of the fixed component or the rotating component while rotating along the circumferential direction. Circumferential movement.
The aperture mechanism according to claim 5, wherein,

The outer shape of each of the plurality of rotating bodies is any one of a disc shape, a cylindrical shape, and a spherical shape.
The aperture mechanism according to any one of claims 1 to 6, wherein:

The width dimension of each of the plurality of aperture plates is fixed,

The guide plate has a recess of a fixed width with a central axis oriented in a radial direction, and each of the plurality of aperture plates is guided by a step provided in the recess.
A camera module characterized by:

It is equipped with the diaphragm mechanism as described in any one of Claims 1-7.
A terminal device characterized by:

It is equipped with the diaphragm mechanism as described in any one of Claims 1-7.