JP2023167696A - Blade driving device and imaging apparatus including the same - Google Patents

Abstract

To provide a blade driving device that can prevent rebound of blades when they are stopped, while avoiding an increase in the thickness of the device in a direction along a driving shaft.SOLUTION: A blade driving device 1 comprises: a bottom board 10 that is provided with an opening S; blades 21-24 that are movable between closed positions and open positions; a rotational driving member 50 that is connected to the blades 21-24 and can rotate around a driving shaft 18 to move the blades 21-24 between the closed positions and open positions; a brake member 90 configured to be rotatable near the rotational driving member 50; and a brake pad 100 that is in slide contact with an outer peripheral surface 94A of the brake member 90 to prevent the rotation of the brake member 90 with the friction. The rotational driving member 50 has pushers 54, 55 configured to be brought into contact with the brake member 90 to push the brake member 90 before the end of at least one operation of an opening operation and a closing operation.SELECTED DRAWING: Figure 2

Description

The present invention relates to a blade drive device and an imaging device equipped with the same, and particularly to a blade drive device used as a shutter in a digital camera or the like.

Digital cameras and the like are often provided with a blade drive mechanism that opens and closes an exposure aperture by rotating a drive lever to move one or more shutter blades connected to the drive lever. The shutter blade in such a blade drive mechanism comes into contact with a stopper and stops, but at that time, it bounces back and a portion of the shutter blade enters the exposure aperture, which may adversely affect photographing. In order to suppress such rebound of the shutter blade, it has been considered to arrange a brake member coaxially with the drive lever that can brake the drive lever by contacting the drive lever (for example, see Patent Document 1).

In such a conventional drive lever braking mechanism, a flat washer is disposed between the brake member and the base plate, and a spring washer is disposed between the brake member and the shaft portion of the drive lever. As a result, the brake member is pressed in the axial direction, and when the brake member is pressed by the shutter blade and rotates, a frictional force is generated between the brake member and the flat washer and spring washer, and this frictional force brakes the drive lever. Ru. However, in such a conventional braking mechanism, the spring washer, the brake member, and the flat washer must be arranged coaxially with the drive lever and lined up in the axial direction, so the thickness along the axial direction inevitably becomes large. This makes it difficult to effectively make the camera thinner.

Japanese Patent Application Publication No. 2005-99318

The present invention has been made in view of the problems of the prior art, and provides a blade drive device and a blade drive device capable of suppressing bounce of the blade when stopped while avoiding thickening in the direction along the drive shaft. An object of the present invention is to provide an imaging device equipped with the following.

According to a first aspect of the present invention, there is provided a blade drive device that can suppress bounce of the blades when they are stopped while avoiding thickening in the direction along the drive shaft. This blade drive device includes a base plate in which an opening is formed, at least one blade movable between a closed position for closing the opening and an open position for opening the opening, and at least one blade for moving between a closed position for closing the opening and an open position for opening the opening. Directly or indirectly coupled, the at least one blade is moved from the closed position to the open position by rotating from a first rotational position to a second rotational position about a drive shaft, a rotational drive member capable of moving the at least one blade from the open position to the closed position by rotating from the rotational position to the first rotational position; and a rotational drive member movable in the vicinity of the rotational drive member. and a sliding member that slides on the outer peripheral surface of the brake member and suppresses movement of the brake member by friction. The rotational drive member is configured to perform at least one of an opening operation of rotating from the first rotational position to the second rotational position and a closing operation of rotating from the second rotational position to the first rotational position. a contact portion configured to contact and push the brake member before termination.

According to a second aspect of the present invention, there is provided an imaging device including the blade driving device described above and an imaging element disposed on a surface on which light transmitted through the blade driving device forms an image.

FIG. 1 is a perspective view showing a blade driving device in an embodiment of the present invention. FIG. 2 is an exploded perspective view of the blade drive device shown in FIG. 1. FIG. 3 is a front view showing the base plate of the blade drive device shown in FIG. 1. FIG. 4A is a front view of the rotational drive member in the blade drive device shown in FIG. 2. FIG. FIG. 4B is a rear view of the rotational drive member shown in FIG. 4A. FIG. 4C is a right side view of the rotational drive member shown in FIG. 4A. 5A is a front view of the blade drive lever in the blade drive device shown in FIG. 2. FIG. FIG. 5B is a rear view of the vane drive lever shown in FIG. 5A. FIG. 5C is a right side view of the vane drive lever shown in FIG. 5A. FIG. 6 is a front view of the link member in the blade drive device shown in FIG. 2. FIG. 7 is a perspective view of a braking member in the blade drive device shown in FIG. 2. FIG. 8 is a perspective view of the brake pad in the blade drive device shown in FIG. 2. FIG. 9A is a plan view schematically showing a state in which the blades of the blade drive device shown in FIG. 1 are in a closed position. FIG. 9B is a plan view schematically showing a state in which the blades of the blade drive device shown in FIG. 1 are in an open position. FIG. 10A is a front view schematically showing a state immediately before the rotational drive member reaches the second rotational position from the first rotational position shown in FIG. 9A to the second rotational position shown in FIG. 9B. FIG. 10B is a front view schematically showing a state in which the rotational drive member has been rotated from the state shown in FIG. 10A to the second rotational position. FIG. 10C is a front view schematically showing a state immediately before the rotational drive member reaches the first rotational position from the second rotational position shown in FIG. 9B. FIG. 10D is a front view schematically showing a state in which the rotational drive member has been rotated from the state shown in FIG. 10C to the first rotation position. FIG. 11 is a front view schematically showing a braking mechanism of a blade drive device in another embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a blade driving device and an imaging device according to the present invention will be described in detail with reference to FIGS. 1 to 11. In FIGS. 1 to 11, the same or corresponding components are given the same reference numerals and redundant explanations will be omitted. Further, in FIGS. 1 to 11, the scale and dimensions of each component may be exaggerated or some components may be omitted. In the following description, unless otherwise specified, terms such as "first" and "second" are used only to distinguish components from each other, and to indicate a specific rank or order. It's not a thing.

FIG. 1 is a perspective view showing a blade driving device 1 according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view. The blade drive device 1 in this embodiment will be described as a shutter device incorporated in an optical device such as a camera, but this is merely an example, and the blade drive device according to the present invention is suitable for use in such a shutter device. It is not limited to.

As shown in FIGS. 1 and 2, the blade driving device 1 in this embodiment includes a base plate 10 in which a rectangular opening (exposed opening) S is formed, and a base plate 10 between the base plate 10 and a cover (not shown). It includes four blades 21 to 24 accommodated in the space formed, and blade arms 31 and 32 connected to the blades 21 to 24. This blade driving device 1 is incorporated into an imaging device equipped with an imaging device (not shown) such as a CCD or CMOS sensor, and the +Z direction is the subject side. Light from the subject passes through the aperture S of the base plate 10 and enters the image sensor disposed on the -Z direction side of the blade driving device 1. Note that depending on the configuration of the camera, the -Z direction may be on the subject side, and the +Z direction may be on the image sensor side.

Each of the blades 21 to 24 is a thin plate-like member that extends in the X direction as a whole, and the four blades 21 to 24 are stacked in order in the -Z direction. The blade 21 is connected to the blade arms 31, 32 by pins 41, 42, respectively, the blade 22 is connected to the blade arms 31, 32 by pins 43, 44, respectively, and the blade 23 is connected to the blade arms 31, 32 by pins 45, 46, respectively. The blade 24 is connected to the blade arms 31 and 32 by pins 47 and 48, respectively.

A circular hole 33 is formed at the end of the blade arm 31, and a substantially rectangular lever connecting hole 34 is formed at a position slightly away from the circular hole 33. This vane arm 31 is configured to be rotatable around the center of the circular hole 33. Further, a circular hole 36 into which a pin 35 is inserted is formed at the end of the blade arm 32, and the pin 35 inserted into this circular hole 36 is inserted into a pin hole (not shown) formed in the main plate 10. ). Thereby, the vane arm 32 is configured to be rotatable around the pin 35.

In this way, the vanes 21 to 24 and the vane arms 31 and 32 constitute a link mechanism. That is, when the vane arm 31 rotates around the center of the circular hole 33 and the vane arm 32 rotates around the pin 35, the vanes 21 to 24 mainly move in the Y direction while changing the area where they overlap each other due to the link mechanism. It looks like this.

FIG. 3 is a front view showing the base plate 10. As shown in FIG. As shown in FIG. 3, the base plate 10 has a substantially cylindrical shaft portion 17 with a circular hole 11 formed in the center. This shaft portion 17 has a claw portion 17A extending in the +Y direction. As shown in FIG. 2, a drive shaft 18 extending in the Z direction is inserted into the circular hole 11 of the shaft portion 17 and fixed therein. Further, a circular hole 12 is formed in the base plate 10 at a position away from the shaft portion 17, and an arcuate groove 13 is formed along an arc centered on the circular hole 12.

As shown in FIGS. 1 and 2, the blade drive device 1 includes an electromagnetic coil unit 80, a rotation drive member 50 that is rotationally driven by the electromagnetic coil unit 80, and a blade drive lever 60 that is rotated by the rotation drive member 50. , a link member 70 that connects the rotary drive member 50 and the blade drive lever 60.

4A is a front view of the rotational drive member 50, FIG. 4B is a rear view, and FIG. 4C is a right side view. As shown in FIGS. 4A to 4C, the rotational drive member 50 includes a shaft portion 51 formed with an insertion hole 51A through which the drive shaft 18 is inserted, and a rotation member fixed to the +Z direction end of the shaft portion 51. an arm portion 53 extending radially outward from the shaft portion 51, and two pushers 54, 55 extending radially outward from the shaft portion 51. The rotor 52 is composed of permanent magnets magnetized with magnetic poles 52A and 52B that are different in the diametrical direction. For example, the magnetic pole 52A is an S pole, and the magnetic pole 52B is an N pole. The rotational drive member 50 is rotatably attached to the drive shaft 18 attached to the circular hole 11 of the base plate 10.

Returning to FIG. 2, the electromagnetic coil unit 80 includes four metal yokes 81A, 81B, 82A, 82B, two bobbins 83A, 83B, and two coils 84 wound around the respective bobbins 83A, 83B. Contains. The coil 84 is connected to a control section (not shown), and energization of the coil 84 is controlled by this control section. This electromagnetic coil unit 80 and the rotor 52 of the rotational drive member 50 constitute a motor (drive unit) that rotates the rotational drive member 50 around the drive shaft 18 .

The yoke 81A and the yoke 81B are arranged in an overlapping manner in the Z direction, and the yoke 82A and the yoke 82B are arranged in an overlapping manner in the Z direction. The yokes 81A, 81B and the yokes 82A, 82B are arranged to face each other in the X direction, and surround the rotor 52 of the rotational drive member 50. Ends of the yokes 81A, 81B, 82A, and 82B are inserted into hollow portions of the bobbins 83A and 83B. In the hollow part of the bobbin 83A, the yoke 81B and the yoke 82A are arranged so as to overlap in the Z direction, and in the hollow part of the bobbin 83B, the yoke 81A and the yoke 82B are arranged so as to overlap in the Z direction.

5A is a front view of the blade drive lever 60, FIG. 5B is a rear view, and FIG. 5C is a right side view. As shown in FIGS. 5A to 5C, the blade drive lever 60 includes a shaft portion 61 extending in the Z direction, an arm portion 62 that curves from the shaft portion 61 and extends outward, and an arm portion 62 that curves from the shaft portion 61 and extends outward. It has an arm portion 63, an arm portion 64 extending linearly from the shaft portion 61, and a drive pin 65 extending from the end of the arm portion 64 in the −Z direction.

An end 61A of the shaft portion 61 of the blade drive lever 60 on the −Z direction side is rotatably inserted into the circular hole 12 of the base plate 10, and further projects from the base plate 10 in the −Z direction. An end portion 61A of the shaft portion 61 of the blade drive lever 60 protruding from the base plate 10 in the −Z direction is inserted into the circular hole 33 of the blade arm 31. Further, the drive pin 65 of the blade drive lever 60 is configured to protrude in the -Z direction through the circular arc groove 13 of the base plate 10, and the drive pin 65 that protrudes in the -Z direction is connected to the lever of the blade arm 31. It is fitted into the connecting hole 34 without any gap. As a result, when the blade drive lever 60 rotates around its shaft portion 61, the drive pin 65 moves within the arcuate groove 13 of the base plate 10, and the blade arm 31 moves into the circular hole 33 (shaft portion 61 of the blade drive lever 60). It rotates around the center. Note that the arm portion 64 of the blade drive lever 60 can come into contact with the end portions on both sides of the arcuate groove 13 of the base plate 10.

FIG. 6 is a front view of the link member 70. As shown in FIG. 6, a circular hole 71 is formed at one end of the link member 70, and a long hole 72 is formed at the other end. As shown in FIG. 2, a pin 75 is inserted into the circular hole 71 of the link member 70. ). As a result, the rotational drive member 50 and the link member 70 are rotatably connected to each other around the pin 75.

Further, a pin 76 is inserted into a circular hole 67 (see FIGS. 5A and 5B) formed in the arm portion 62 of the blade drive lever 60, and the pin 76 is inserted so as to protrude from the blade drive lever 60 in the -Z direction. It has become. A pin 76 protruding from the blade drive lever 60 in the -Z direction is inserted into an elongated hole 72 of the link member 70 and is movable inside the elongated hole 72. In this way, the blade drive lever 60 and the link member 70 are connected via the pin 76.

Returning to FIG. 2, a braking member 90 rotatable around the shaft portion 17 is arranged on the shaft portion 17 of the base plate 10. Further, a brake pad 100 (sliding member) is arranged adjacent to the braking member 90. The base plate 10 has a spring receiving part 14 on the +Y direction side of the brake pad 100, and a coil spring 19 (biasing member) is loaded in a compressed state between the spring receiving part 14 and the brake pad 100. has been done. The brake pad 100 is pressed toward the braking member 90 by the biasing force of the coil spring 19 .

FIG. 7 is a perspective view of the brake member 90. As shown in FIG. 7, the braking member 90 includes a ring portion 92 in which an oval hole 91 into which the shaft portion 17 of the main plate 10 is inserted, a stopper piece 93 extending outward from the ring portion 92, and a ring portion The brake piece 94 has a larger thickness in the Z direction than the brake piece 92. The outer peripheral surface 94A of the brake piece 94 is constituted by a part of a cylindrical surface. One side 95 of the brake piece 94 can come into contact with the pusher 54 (first pusher) of the rotational drive member 50, and the other side 96 can contact the pusher 55 (second pusher) of the rotational drive member 50. It is possible to contact.

FIG. 8 is a perspective view of the brake pad 100. As shown in FIG. 8, the brake pad 100 includes a pad body 101 having a sliding surface 101A that slides into contact with the outer circumferential surface 94A of the brake piece 94 of the braking member 90, and a spring receiving portion 102 that receives the coil spring 19. There is. The sliding surface 101A is constituted by a part of a cylindrical surface having the same diameter as the cylindrical surface constituting the outer circumferential surface 94A of the brake piece 94.

It is preferable that the braking member 90 and the brake pad 100 are formed from a combination of materials that easily generate frictional force when they slide into contact with each other. For example, one of the braking member 90 and the brake pad 100 can be made of acetal, and the other can be made of nylon.

The blades 21 to 24 are placed in a position where the opening S of the main plate 10 is closed (hereinafter referred to as the "closed position") as shown in FIG. 9A, and a position where the opening S of the main plate 10 is opened as shown in FIG. 9B (hereinafter referred to as the "closed position"). (referred to as the "open position"). In general, the operation of the blade drive device in a camera is normal, where the initial state is when the blade closes the exposure aperture, and when the release button is pressed to take a picture, the blade operates immediately from the initial state. There is a close operation and a normally open operation in which the blade opens the exposure aperture as an initial state and operates only in the final stage of photography after the release button is pressed. Although the blade drive device 1 in this embodiment is capable of responding to any operation, a case in which normally closed operation is performed will be described here.

In the normally closed operation, when a release button (not shown) is pressed, the blades 21-24 move from the closed position shown in FIG. 9A to the open position shown in FIG. 9B. In the state shown in FIG. 9A, the blade drive lever 60 is at the maximum counterclockwise rotation position, and the arm portion 64 of the blade drive lever 60 hits the terminal end of the arcuate groove 13 of the base plate 10 in the +Y direction. are in contact with each other. At this time, the coil 84 of the electromagnetic coil unit 80 is not energized, but the magnetic poles formed by the two magnetic poles 52A, 52B of the rotor 52 of the rotational drive member 50 and the four yokes 81A, 81B, 82A, 82B. A clockwise rotational force is applied to the rotor 52 of the rotary drive member 50 due to the magnetic attraction and repulsion generated between the two. Therefore, a counterclockwise rotational force is generated on the blade drive lever 60 via the link member 70, and the blade drive lever 60 is held at the position shown in FIG. 9A. The position of the rotational drive member 50 at this time will be referred to as a "first rotational position."

When the photographer presses the release button in the state shown in FIG. 9A, the coil 84 is energized, and, for example, the yokes 81A and 81B have N poles, and the yokes 82A and 82B have S poles. This change in magnetic poles generates a counterclockwise rotational force in the rotor 52 of the rotary drive member 50, causing the rotary drive member 50 to rotate counterclockwise about the drive shaft 18. Accordingly, the blade drive lever 60 rotates clockwise via the link member 70 connected to the arm portion 53 of the rotational drive member 50. When the blade drive lever 60 rotates clockwise, the blade arm 31 is rotated clockwise by the drive pin 65 of the blade drive lever 60, and the blades 21 to 24 are moved in the -Y direction by the above-mentioned link mechanism. Finally, the arm portion 64 of the blade drive lever 60 comes into contact with the terminal end of the arcuate groove 13 of the base plate 10 on the −Y direction side, so that the blade drive lever 60 stops, and the blades 21 to 24 move through the opening of the base plate 10. Move to the open position (FIG. 9B) where S is released.

Here, in the state shown in FIG. 9B, magnetic A counterclockwise rotational force is applied to the rotor 52 of the rotary drive member 50 due to the attractive force and the repulsive force. Therefore, after the blades 21 to 24 have moved to the open position shown in FIG. 9B, even if the coil 84 is de-energized, a clockwise rotational force is generated in the blade drive lever 60 via the link member 70, causing the blade to move. Drive lever 60 is held in the position shown in Figure 9B. The position of the rotational drive member 50 at this time will be referred to as a "second rotational position."

In this manner, when the blades 21 to 24 move from the closed position shown in FIG. 9A to the open position shown in FIG. 9B, the rotational drive member 50 rotates counterclockwise from the first rotational position to the second rotational position. (opening operation), but just before the rotary drive member 50 reaches the second rotation position, the pusher 54 of the rotary drive member 50 contacts the side portion 95 of the brake piece 94 of the brake member 90, as shown in FIG. 10A. It is supposed to be done. When the rotary drive member 50 further rotates counterclockwise from this state, the pusher 54 pushes the brake piece 94 of the braking member 90 counterclockwise. Since the brake pad 100 is pressed toward the brake piece 94 of the brake member 90 by the coil spring 19, sliding contact occurs between the outer peripheral surface 94A of the brake piece 94 of the brake member 90 and the sliding surface 101A of the brake pad 100. Frictional force is generated, and the rotation of the braking member 90 and, in turn, the rotation of the rotary drive member 50 is decelerated. This makes it possible to reduce the speed of the blades 21 to 24 immediately before they stop, and to suppress bouncing back when the blades 21 to 24 stop. The rotary drive member 50 rotates until the arm portion 64 of the blade drive lever 60 finally comes into contact with the terminal end of the arcuate groove 13 of the base plate 10 on the −Y direction side, as shown in FIG. 10B. reaches the rotational position. The position of the braking member 90 at this time will be referred to as a "first standby position."

After the blades 21 to 24 move to the open position shown in FIG. 9B as described above, the charges accumulated in the image sensor are released, and accumulation of charges for photographing begins. After a predetermined time has elapsed, a signal from the control circuit causes a current to flow through the coil 84 in the opposite direction to the current previously passed, and for example, S poles are generated in the yokes 81A and 81B, and N poles are generated in the yokes 82A and 82B. . This change in magnetic poles generates a clockwise rotational force in the rotor 52 of the rotary drive member 50, causing the rotary drive member 50 to rotate clockwise about the drive shaft 18. Accordingly, the blade drive lever 60 rotates counterclockwise via the link member 70 connected to the arm portion 53 of the rotational drive member 50. When the blade drive lever 60 rotates counterclockwise, the blade arm 31 is rotated counterclockwise by the drive pin 65 of the blade drive lever 60, and the blades 21 to 24 are moved in the +Y direction by the above-mentioned link mechanism. Finally, the arm portion 64 of the blade drive lever 60 comes into contact with the terminal end of the circular arc groove 13 of the base plate 10 on the +Y direction side, so that the blade drive lever 60 stops, and the blades 21 to 24 are moved to the opening S of the base plate 10. to the closed position (FIG. 9A).

In this way, when the blades 21 to 24 move from the open position shown in FIG. 9B to the closed position shown in FIG. 9A, the rotational drive member 50 rotates clockwise from the second rotational position to the first rotational position. (closing operation) is just before the rotary drive member 50 reaches the first rotation position, as shown in FIG. 10C, the pusher 55 of the rotary drive member 50 (located at the first standby position) The member 90 is adapted to contact the side 96 of the brake piece 94. When the rotary drive member 50 further rotates clockwise from this state, the pusher 55 pushes the brake piece 94 of the brake member 90 clockwise. Since the brake pad 100 is pressed toward the brake piece 94 of the brake member 90 by the coil spring 19, sliding contact occurs between the outer peripheral surface 94A of the brake piece 94 of the brake member 90 and the sliding surface 101A of the brake pad 100. Frictional force is generated, and the rotation of the braking member 90 and, in turn, the rotation of the rotary drive member 50 is decelerated. This makes it possible to reduce the speed of the blades 21 to 24 immediately before they stop, and to suppress bouncing back when the blades 21 to 24 stop. The rotational drive member 50 rotates until the arm portion 64 of the blade drive lever 60 finally comes into contact with the terminal end of the arcuate groove 13 of the base plate 10 on the +Y direction side, as shown in FIG. 10D. Reach rotational position. The position of the braking member 90 at this time will be referred to as a "second standby position." In the above-described opening operation of the rotary drive member 50, the pusher 54 of the rotary drive member 50 comes into contact with the side portion 95 of the brake piece 94 of the braking member 90 located at the second standby position. (See Figure 10A).

In this way, the pushers 54 and 55 of the rotary drive member 50 in this embodiment are configured to contact the brake piece 94 of the brake member 90 and push the brake member 90 before the opening operation and before the closing operation. functions as a contact part. In this way, the pushers 54 and 55 as the contact portions contact the brake piece 94 of the brake member 90 and press the brake member 90 before the opening operation and the closing operation of the rotary drive member 50 are completed. Frictional force is generated due to sliding contact between the outer circumferential surface 94A of the brake piece 94 and the sliding contact surface 101A of the brake pad 100, and the rotation of the braking member 90 and, by extension, the rotation of the rotary drive member 50 is decelerated. This makes it possible to reduce the speed of the blades 21 to 24 before they stop, and to suppress bouncing back when the blades 21 to 24 stop. Moreover, since the braking member 90 and the brake pad 100 are in sliding contact on the radially outer side of the rotary drive member 50, it is possible to prevent the blade drive device 1 from becoming thicker in the direction along the drive shaft 18.

In addition, the pusher 55 in this embodiment can move the braking member 90 to a position (first standby position) where the pusher 54 of the rotational drive member 50 can contact, and the pusher 54 can move the brake member 90 to a position where the pusher 54 of the rotational drive member 50 can contact The braking member 90 can be moved to a position (second standby position) where the brake member 55 can be contacted. Therefore, it is possible to reduce the speed of the blades 21 to 24 both before the opening operation ends and before the closing operation ends.

Here, as shown in FIG. 2, the base plate 10 has regulating protrusions 15 and 16 (limiting portions) that protrude in the +Z direction. These regulating protrusions 15 and 16 are disposed adjacent to the stopper piece 93 of the brake member 90 in the circumferential direction, and can engage with the stopper piece 93 of the brake member 90. As shown in FIG. 10D, the regulating protrusion 15 regulates the clockwise rotation of the braking member 90, and as shown in FIG. 10B, the regulating protrusion 16 is configured to regulate the counterclockwise rotation of the braking member 90. The regulating protrusions 15 and 16 define the rotation range of the braking member 90. In this way, the regulating protrusions 15 and 16 of the base plate 10 can define the rotatable range of the brake member 90, and malfunctions due to movement of the brake member 90 to an unintended position can be prevented.

In this embodiment, the elliptical hole 91 of the brake member 90 is larger than the outer diameter of the shaft 17 of the base plate 10 in order to allow the brake member 90 to be attached to the shaft 17 of the base plate 10. After the braking member 90 is attached to the shaft portion 17 of the main plate 10, the braking member 90 is pushed in the -Y direction by the coil spring 19, so that the claw portion 17A provided on the shaft portion 17 of the main plate 10 engages the ring portion 92 of the braking member 90. engage with. Therefore, the braking member 90 is difficult to come off from the shaft portion 17 of the base plate 10.

The braking member 90 in this embodiment is configured to rotate around the shaft portion 17 of the base plate 10 and rotate around the same axis as the rotational drive member 50; It does not necessarily have to be arranged around the axis, and as long as it is movable near the rotary drive member 50, it does not necessarily need to rotate around the axis.

Further, in the present embodiment, the blade drive lever 60 and the link member 70 are interposed between the rotation drive member 50 and the blade arm 31, but even if the rotation drive member 50 is directly connected to the blade arm 31, good.

In this embodiment, the rotational drive member 50 is driven by the electromagnetic coil unit 80, but the method of driving the rotational drive member 50 is not limited to electromagnetic one, and the rotation drive member 50 is rotated using a biasing means such as a spring. The driving member 50 may be configured to be driven.

In this embodiment, the brake pad 100 is pressed against the outer peripheral surface 94A of the brake piece 94 of the brake member 90 by the coil spring 19. For example, as shown in FIG. A leaf spring 220 is arranged in a bent state between the brake piece 94 and the sliding surface 220A of the leaf spring 220 is biased toward the outer peripheral surface 94A of the brake piece 94 of the braking member 90. It's okay. In this case, the spring receiving portion 14, coil spring 19, and brake pad 100 shown in FIG. 2 can be omitted. It is preferable that the leaf spring 220 is made of a material that easily generates a frictional force when the braking member 90 comes into sliding contact with the leaf spring 220 .

As described above, according to the first aspect of the present invention, there is provided a blade drive device that can suppress bounce of the blades when they are stopped while avoiding thickening in the direction along the drive shaft. Specifically, the blade drive device according to the present invention can employ the following configuration.

(Configuration 1)
The blade drive device includes a base plate in which an opening is formed, at least one blade that is movable between a closed position that closes the opening and an open position that opens the opening, and a blade that directly drives the at least one blade. or indirectly connected to move the at least one blade from the closed position to the open position by rotating from the first rotational position to the second rotational position about the drive shaft, and a rotational drive member capable of moving the at least one blade from the open position to the closed position by rotating from the rotational position to the first rotational position; and a rotational drive member movable in the vicinity of the rotational drive member. and a sliding member that slides on the outer peripheral surface of the brake member and suppresses movement of the brake member by friction. The rotational drive member is configured to perform at least one of an opening operation of rotating from the first rotational position to the second rotational position and a closing operation of rotating from the second rotational position to the first rotational position. a contact portion configured to contact and push the brake member before termination.

According to such a configuration, the contact portion of the rotary drive member contacts the brake member and pushes the brake member before the end of at least one of the opening operation and the closing operation of the rotary drive member, so that the outer periphery of the brake member Frictional force is generated due to the sliding contact between the surface and the sliding member, and the rotation of the braking member and, in turn, the rotation of the rotary drive member is decelerated. Thereby, the speed before the blade stops can be reduced, and it is possible to suppress bouncing back when the blade stops. Moreover, since the braking member and the sliding member come into sliding contact on the radially outer side of the rotary drive member, it is possible to avoid the blade drive device from becoming thicker in the direction along the drive shaft.

(Configuration 2)
In the above configuration 1, the contact portion of the rotary drive member includes a first pusher that pushes the brake member in a first direction before the end of the opening operation, and a first pusher that pushes the brake member in the first direction before the end of the closing operation. A second pusher for pushing in a second direction opposite to the first direction is preferably included. These pushers can decelerate the rotation of the rotary drive member both before the opening operation of the rotary drive member ends and before the end of the closing operation of the rotary drive member.

(Configuration 3)
In the above configuration 2, the first pusher of the rotary drive member is configured to move the braking member to a first standby position at the end of the opening operation, and the first pusher of the rotary drive member is configured to move the braking member to a first standby position. The pusher may be configured to contact the braking member located at the first standby position before the closing operation ends. According to such a configuration, the braking member can be moved by the first pusher of the rotary drive member to a position (first standby position) where the second pusher of the rotary drive member can contact.

(Configuration 4)
In the above configuration 2 or 3, the second pusher of the rotary drive member is configured to move the braking member to a second standby position at the end of the closing operation, and the second pusher of the rotary drive member is configured to move the braking member to a second standby position. The first pusher may be configured to contact the braking member located at the second standby position before the opening operation ends. According to such a configuration, the second pusher of the rotary drive member can move the braking member to a position (second standby position) where the first pusher of the rotary drive member can contact.

(Configuration 5)
In any one of configurations 1 to 4 above, the base plate has a regulating part that defines a movement range of the braking member, and the braking member has a stopper piece that can engage with the regulating part of the base plate. is preferred. According to such a configuration, the range in which the braking member can move can be defined by the regulating portion of the base plate, and malfunctions due to movement of the braking member to an unintended position can be prevented.

(Configuration 6)
In any one of configurations 1 to 5 above, the blade drive device may further include an urging member that presses the sliding member against the outer circumferential surface of the braking member.

(Configuration 7)
In any one of configurations 1 to 5 above, the sliding member may be constituted by a spring member biased toward the outer circumferential surface of the braking member.

According to a second aspect of the present invention, the blade driving device according to any one of configurations 1 to 7 above and an image sensor disposed on a surface on which light transmitted through the blade driving device is imaged are provided. An imaging device is provided.

Although preferred embodiments of the present invention have been described so far, it goes without saying that the present invention is not limited to the above-described embodiments and may be implemented in various different forms within the scope of its technical idea.

1 Blade drive device 10 Base plate 13 Arc groove 14 Spring receiving portion 15, 16 Regulating protrusion (regulating portion)
17 Shaft 18 Drive shaft 19 Coil spring (biasing member)
21-24 Blades 31, 32 Blade arm 50 Rotation drive member 51 Shaft 52 Rotor 53 Arm 54 (First) pusher 55 (Second) pusher 60 Blade drive lever 61 Shaft 62-64 Arm 65 Drive Pin 70 Link member 80 Electromagnetic coil unit 81A, 81B, 82A, 82B Yoke 83A, 83B Bobbin 84 Coil 90 Braking member 93 Stopper piece 94 Brake piece 94A Outer surface 100 Brake pad (sliding member)
220 Leaf spring S opening

Claims (8)

A base plate with an opening formed therein;
at least one blade movable between a closed position for closing the opening and an open position for opening the opening;
The at least one blade is connected directly or indirectly to the at least one blade and rotates about the drive shaft from the first rotational position to the second rotational position to move the at least one blade from the closed position to the open position. a rotary drive member capable of moving the at least one blade from the open position to the closed position by rotating from the second rotation position to the first rotation position;
a braking member configured to be movable near the rotational drive member;
a sliding contact member that slides on the outer peripheral surface of the braking member and suppresses movement of the braking member by friction;
The rotational drive member is configured to perform at least one of an opening operation of rotating from the first rotational position to the second rotational position and a closing operation of rotating from the second rotational position to the first rotational position. a contact portion configured to contact and push the braking member before termination;
Vane drive device. The contact portion of the rotational drive member is
a first pusher that pushes the braking member in a first direction before the opening operation ends;
The blade drive device according to claim 1, further comprising a second pusher that pushes the braking member in a second direction opposite to the first direction before the closing operation ends. The first pusher of the rotary drive member is configured to move the braking member to a first standby position at the end of the opening operation,
The second pusher of the rotational drive member is configured to contact the braking member located at the first standby position before the closing operation ends;
The blade drive device according to claim 2. The second pusher of the rotary drive member is configured to move the braking member to a second standby position at the end of the closing operation,
The first pusher of the rotary drive member is configured to contact the braking member located at the second standby position before the opening operation ends;
The blade drive device according to claim 2. The base plate has a regulating portion that defines a movement range of the braking member,
The braking member has a stopper piece that can engage with the regulating portion of the base plate.
The blade drive device according to any one of claims 1 to 4. The blade drive device according to any one of claims 1 to 4, further comprising a biasing member that presses the sliding member against the outer circumferential surface of the braking member. The blade drive device according to any one of claims 1 to 4, wherein the sliding member is constituted by a spring member biased toward the outer circumferential surface of the braking member. The blade drive device according to any one of claims 1 to 4,
An imaging device comprising: an imaging element disposed on a surface on which light transmitted through the blade driving device forms an image.

Images