JP2023132113A - Blade driving device, and imaging device including the same - Google Patents

Abstract

To provide a blade driving device that can effectively reduce an impact occurring upon stoppage of a blade.SOLUTION: A blade driving device 1 comprises: a front blade arm 31 that is rotatably configured centering around a support shaft 41; front blades 21 to 24 that are coupled to the front blade arm 31; a front blade driving lever 51 that has a front blade driving unit 513 to be coupled to the front blade arm 31; an elastic plate member 210 that is elastically deformable in a Z-direction; and a buffer member 250 that is disposed inside the elastic plate member 210, and is elastically deformable in the Z-direction. The front blade driving lever 51 is configured to rotate centering around a front driving shaft 11, and can move the front blade driving unit 513 from a driving start position to a driving end position. The elastic plate member 210 is disposed in a position where the front blade arm 31 is contactable when the front blade driving unit 513 of the front blade driving lever 51 stops in the driving end position.SELECTED DRAWING: Figure 2

Description

The present invention relates to a blade driving device and an imaging device equipped with the same.

2. Description of the Related Art In digital cameras and the like, a focal plane shutter is known that performs exposure and shielding by moving a front curtain blade and a rear curtain blade with a time difference (for example, see Patent Document 1). As such a focal plane shutter, one is known in which a blade drive lever connected to a leading blade and a trailing blade is moved by the force of a spring during photographing. This blade drive lever is configured to move inside a groove formed in the base plate, and a damper may be provided at the end of this groove to reduce shock and vibration when the blade drive lever hits the end of the groove. many.

However, as the speed of the shutter increases, the impact that occurs when the blades end their travel is also increasing, and it is no longer possible to sufficiently suppress the deflection and vibration of members caused by such impact using only the damper described above. Such deflection and vibration cause a decrease in the quality of captured images and also decrease the durability of the camera. Therefore, in addition to conventional dampers, there is a need for a mechanism that can effectively reduce the impact that occurs when the blade ends its travel.

Japanese Patent Application Publication No. 2011-113060

The present invention has been made in view of the problems of the prior art, and aims to provide a blade drive device that can effectively reduce the impact that occurs when the blades stop, and an imaging device equipped with the same. purpose.

According to a first aspect of the present invention, a blade driving device is provided that can effectively reduce the impact that occurs when the blade stops. This blade drive device includes a base plate provided with an opening, a drive shaft extending from the base plate, a support shaft extending from the base plate coaxially with the drive shaft, and a blade arm configured to be rotatable about the support shaft. a blade connected to the blade arm and movable to open and close the opening; a blade drive lever having a blade drive unit connected to the blade arm; and an elastic blade that is elastically deformable in a first direction. The device includes a plate member and a buffer member disposed inside the elastic plate member and elastically deformable in the first direction. The blade drive lever is configured to rotate around the drive shaft and move the blade drive unit from a drive start position to a drive end position. The elastic plate member is arranged at a position where the blade arm or the blade can come into contact with the blade arm or the blade when the blade drive portion of the blade drive lever stops at the drive end position.

According to a second aspect of the present invention, an imaging device comprising the above-mentioned blade driving device and an imaging element disposed on a surface on which light transmitted through an aperture provided in the base plate of the blade driving device forms an image. is provided.

FIG. 1 is a front view showing a blade driving device in an embodiment of the present invention. FIG. 2 is a rear view of the blade drive device of FIG. 1. FIG. 3 is an exploded perspective view of the blade drive device of FIG. 1. FIG. 4 is an exploded perspective view showing a leading blade and a leading blade arm in the blade driving device of FIG. 1. FIG. FIG. 5 is an exploded perspective view showing a rear blade and a rear blade arm in the blade drive device of FIG. 1. FIG. FIG. 6A is a schematic diagram illustrating the operation of the blade drive device of FIG. 1. FIG. 6B is a schematic diagram illustrating the operation of the blade drive device of FIG. 1. FIG. 6C is a schematic diagram illustrating the operation of the blade drive device of FIG. 1. FIG. 7 is a perspective view showing the impact reduction mechanism in the blade drive device of FIG. 1. 8A is a rear view showing the elastic plate member in the impact reduction mechanism shown in FIG. 7. FIG. FIG. 8B is a bottom view of the elastic plate member of FIG. 8. FIG. 9 is a rear view showing a modification of the elastic plate member shown in FIG. 8A.

Embodiments of a blade driving device and an imaging device according to the present invention will be described in detail below with reference to FIGS. 1 to 9. In FIGS. 1 to 9, the same or corresponding components are given the same reference numerals and redundant explanations will be omitted. Further, in FIGS. 1 to 9, 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 front view, FIG. 2 is a rear view, and FIG. 3 is an exploded perspective view of a blade driving device 1 according to an embodiment of the present invention. The blade drive device 1 in this embodiment will be described as a focal plane shutter 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 with such a shutter. It is not limited to. Note that FIGS. 1 to 3 show the state when the exposure operation by the camera is completed.

As shown in FIGS. 1 to 3, the blade drive 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 eight blades 21 to 28 accommodated in the space formed. 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 in FIG. 3, the −Y direction side is the object side. Light from the subject passes through the aperture S of the base plate 10 and enters the image sensor disposed on the +Y direction side of the blade drive device 1. Note that depending on the configuration of the camera, the +Y direction side may be the subject side, and the -Y direction side may be the imaging element side.

Each of the blades 21 to 28 is a thin plate-like member that extends in the X direction as a whole, and the eight blades 21 to 28 are stacked in order in the +Y direction. In this embodiment, among the eight blades 21 to 28, blades 21 to 24 are leading blades forming a front curtain of the focal plane shutter, and blades 25 to 28 are trailing blades forming a rear curtain. There is.

The blade drive device 1 includes leading blade arms 31, 32 connected to leading blades 21-24, and trailing blade arms 33, 34 connected to trailing blades 25-28. FIG. 4 is an exploded perspective view showing the leading blades 21-24 and leading blade arms 31, 32, and FIG. 5 is an exploded perspective view showing the trailing blades 25-28 and trailing blade arms 33, 34. In this embodiment, the leading blade 21 corresponds to a "blade" according to the present invention, and the leading blade arm 31 corresponds to a "blade arm" according to the present invention.

As shown in FIG. 4, the leading blade 21 is connected to leading blade arms 31, 32 by pins 101, 102, respectively, the leading blade 22 is connected to leading blade arms 31, 32, respectively by pins 103, 104, and the leading blade 23 is connected to leading blade arms 31, 32 by pins 103, 104, respectively. are connected to the leading blade arms 31, 32 by pins 105, 106, respectively, and the leading blade 24 is connected to the leading blade arms 31, 32 by pins 107, 108, respectively. In this way, each of the leading blades 21 to 24 and the leading blade arms 31 and 32 constitute a link mechanism.

Further, as shown in FIG. 5, the rear blade 25 is connected to the rear blade arms 33, 34 by pins 111, 112, respectively, and the rear blade 26 is connected to the rear blade arms 33, 34, respectively by pins 113, 114, The blade 27 is connected to the rear blade arms 33, 34 by pins 115, 116, respectively, and the rear blade 28 is connected to the rear blade arms 33, 34 by pins 117, 118, respectively. In this way, each of the rear blades 25 to 28 and the rear blade arms 33 and 34 constitute a link mechanism.

As shown in FIG. 3, the main plate 10 includes a leading blade drive shaft 11 (corresponding to the "drive shaft" according to the present invention in this embodiment), a trailing blade drive shaft 12, and a camshaft 13 extending in the +Y direction. It is formed. Furthermore, an arcuate groove 14 along an arc centered on the leading blade drive shaft 11 and an arcuate groove 15 along an arc centered on the trailing blade drive shaft 12 are formed in the base plate 10 . A cover plate (not shown) is attached to the +Y direction side of the base plate 10.

Further, as shown in FIG. 2, support shafts 41 to 44 extending in the -Y direction are formed on the base plate 10. Among these support shafts 41 to 44, support shaft 41 (corresponding to the "support shaft" according to the present invention in this embodiment) is located coaxially with the aforementioned leading blade drive shaft 11, and support shaft 42 is located coaxially with the leading blade drive shaft 11 described above. It is located coaxially with the rear blade drive shaft 12.

As shown in FIG. 4, a cylindrical sleeve 312 into which the support shaft 41 of the main plate 10 is inserted is provided near the end of the leading blade arm 31. By being inserted, the leading blade arm 31 can rotate around the support shaft 41 of the main plate 10. A substantially rectangular lever connection hole 314 is formed at a position slightly away from the cylindrical sleeve 312 of the leading blade arm 31. Further, a shaft hole 322 into which the support shaft 43 of the main plate 10 is inserted is formed near the end of the leading blade arm 32. , the leading blade arm 32 can rotate around a support shaft 43 of the main plate 10.

As shown in FIG. 4, the leading blades 21 to 24 are connected to leading blade arms 31 and 32 in an overlapping state in order in the Y direction. Therefore, when the leading blade arm 31 rotates around the support shaft 41 and the leading blade arm 32 rotates around the support shaft 43, the above-mentioned link mechanism changes the area where the leading blades 21 to 24 overlap each other, and It mainly moves in the Z direction.

As shown in FIG. 5, a cylindrical sleeve 342 through which the support shaft 42 of the main plate 10 is inserted is provided near the end of the rear blade arm 34. is inserted, so that the rear blade arm 34 can rotate around the support shaft 42 of the main plate 10. A substantially rectangular lever connection hole 344 is formed at a position slightly away from the cylindrical sleeve 342 of the rear blade arm 34. Further, near the end of the rear blade arm 33, a shaft hole 332 is formed into which the support shaft 44 of the main plate 10 is inserted. By inserting the support shaft 44 into the shaft hole 332 of the rear blade arm 33, the rear blade arm 33 can rotate around the support shaft 44 of the base plate 10.

As shown in FIG. 5, the rear blades 25 to 28 are connected to rear blade arms 33 and 34 in a sequentially overlapping manner in the Y direction. Therefore, when the rear blade arm 33 rotates around the support shaft 44 and the rear blade arm 34 rotates around the support shaft 42, the above-mentioned link mechanism changes the area where the rear blades 25 to 28 overlap each other. It mainly moves in the Z direction.

Returning to FIG. 3, the blade drive device 1 includes a leading blade drive lever 51 (corresponding to the "blade drive lever" according to the present invention in this embodiment) attached to the leading blade drive shaft 11 of the main plate 10, A trailing blade drive lever 52 attached to the trailing blade drive shaft 12 , a leading blade driving spring 53 attached to the leading blade driving lever 51 , a trailing blade driving spring 54 attached to the trailing blade driving lever 52 , and the base plate 10 A cam member 61 attached to the camshaft 13 of It has a rear blade electromagnet 92.

In this embodiment, the leading blade drive spring 53 is constituted by a torsion coil spring, and is in a twisted state so as to bias the leading blade drive lever 51 clockwise around the leading blade drive shaft 11 in FIG. It is located in Similarly, the rear blade drive spring 54 is composed of a torsion coil spring, and is arranged in a twisted state so as to bias the rear blade drive lever 52 clockwise around the rear blade drive shaft 12 in FIG. There is.

The cam member 61 includes a shaft portion 611 through which the camshaft 13 of the main plate 10 is inserted, an operating portion 612 extending radially outward from the shaft portion 611, and an operating portion 612 extending radially outward from the shaft portion 611 in a direction different from the operating portion 612. It has a leading blade cam piece 613 that extends, and a trailing blade cam piece 622 that extends radially outward from the shaft portion 611 in a direction different from that of the operating portion 612 and the leading blade cam piece 613. The cam shaft 13 of the base plate 10 is inserted through the shaft portion 611 of the cam member 61, so that the cam member 61 can rotate around the cam shaft 13 of the base plate 10. In this embodiment, the cam spring 63 is a torsion coil spring, and is configured to bias the cam member 61 counterclockwise around the cam shaft 13 in FIG.

As shown in FIGS. 1 and 3, the leading blade drive lever 51 includes a shaft portion 511 through which the leading blade driving shaft 11 of the base plate 10 is inserted, a metal piece 516, and a holder 517 that holds the metal piece 516. are doing. The leading blade driving shaft 11 of the main plate 10 is inserted into the shaft portion 511 of the leading blade driving lever 51, so that the leading blade driving lever 51 can rotate around the leading blade driving shaft 11 of the main plate 10.

The leading blade driving lever 51 includes a leading blade driving part 513 (see FIG. 2, which corresponds to the "blade driving part" according to the present invention in this embodiment) that protrudes in the -Y direction of the main plate 10 through the arcuate groove 14 of the main plate 10. ), and when the leading blade drive lever 51 rotates around the leading blade drive shaft 11, the leading blade drive portion 513 of the leading blade drive lever 51 moves within the arcuate groove 14. Note that a shock absorbing damper 17 is provided at the end of the arcuate groove 14 of the base plate 10 on the +Z direction side.

The leading blade driving portion 513 passes through the arcuate groove 14 of the base plate 10 and fits into the lever connection hole 314 of the leading blade arm 31 without a gap, as shown in FIG. As described above, since the support shaft 41 of the main plate 10 is located coaxially with the leading blade drive shaft 11, when the leading blade driving section 513 of the leading blade driving lever 51 rotates around the leading blade driving shaft 11, The leading blade arm 31 rotates around a support shaft 41. As a result, the leading blade arm 32 rotates around the support shaft 43 via the link mechanism described above, and the leading blades 21 to 24 move primarily in the Z direction while changing the overlapping area.

As shown in FIGS. 1 and 3, the rear blade drive lever 52 includes a shaft portion 521 through which the rear blade drive shaft 12 of the base plate 10 is inserted, a metal piece 526, and a holder 527 that holds the metal piece 526. are doing. By inserting the rear blade drive shaft 12 of the main plate 10 into the shaft portion 521 of the rear blade drive lever 52, the rear blade drive lever 52 can rotate around the rear blade drive shaft 12 of the main plate 10. .

The rear blade drive lever 52 has a rear blade drive portion 523 (see FIG. 2) that protrudes in the −Y direction of the base plate 10 through the arc groove 15 of the base plate 10, and the rear blade drive lever 52 is configured to drive the rear blade. When rotated about the shaft 12, the rear blade drive portion 523 of the rear blade drive lever 52 moves within the arcuate groove 15. Note that a shock absorbing damper 18 is provided at the end of the arcuate groove 15 of the base plate 10 on the +Z direction side.

The rear blade drive portion 523 passes through the arcuate groove 15 of the base plate 10 and fits into the lever connection hole 344 of the rear blade arm 34 without a gap, as shown in FIG. As described above, since the support shaft 42 of the base plate 10 is located coaxially with the rear blade drive shaft 12, when the rear blade drive portion 523 of the rear blade drive lever 52 rotates around the rear blade drive shaft 12, The rear blade arm 34 rotates around a support shaft 42 . As a result, the rear blade arm 33 rotates around the support shaft 44 via the link mechanism described above, and the rear blades 25 to 28 move primarily in the Z direction while changing the area where they overlap.

As described above, FIG. 1 shows a state in which the exposure operation has been completed, and in this state, the leading blades 21 to 24 have retreated from the opening S of the main plate 10 in the +Z direction, and the trailing blades 25 to 28 is blocking the opening S of the main plate 10. From this state, the leading blade drive lever 51 is charged by rotating counterclockwise against the biasing force of the leading blade drive spring 53 by the following operation, and the trailing blade drive lever 52 is rotated by the biasing force of the trailing blade drive spring 54. It can be charged by rotating counterclockwise against the

That is, by pushing the operating portion 612 of the cam member 61 with a drive member (not shown), the cam member 61 is rotated clockwise in FIG. 1 about the cam shaft 13 against the biasing force of the cam spring 63. When the cam member 61 rotates clockwise, the leading blade cam piece 613 contacts the leading blade driving lever 51, and the leading blade driving lever 51 rotates counterclockwise in FIG. 1. Further, when the cam member 61 rotates clockwise, the rear blade cam piece 622 contacts the rear blade drive lever 52, and the rear blade drive lever 52 rotates counterclockwise in FIG. 1. In this way, the leading blade drive lever 51 and the trailing blade drive lever 52 are each charged. FIG. 6A schematically shows the state at this time.

At this time, the leading blade drive lever 51 is held in the charged position by the metal piece 516 being electromagnetically attracted by the leading blade electromagnet 91. Further, the rear blade drive lever 52 is held in the charged position by the metal piece 526 being electromagnetically attracted by the rear blade electromagnet 92.

Then, the electromagnetic attraction by the leading blade electromagnet 91 is released at a predetermined timing, and thereby the leading blade drive lever 51 is rotated clockwise by the biasing force of the leading blade driving spring 53. Along with this, the leading blades 21 to 24 mainly move in the +Z direction while changing the mutually overlapping area via the leading blade arm 31 connected to the leading blade driving part 513 of the leading blade driving lever 51 and the above-mentioned link mechanism. do.

After the electromagnetic attraction by the leading blade electromagnet 91 is released, the electromagnetic attraction by the trailing blade electromagnet 92 is released at a predetermined timing, and as a result, the trailing blade drive lever 52 is rotated clockwise by the biasing force of the trailing blade drive spring 54. Rotate. Along with this, the trailing blades 25 to 28 mainly move in the +Z direction while changing the mutually overlapping area via the trailing blade arm 34 connected to the trailing blade drive section 523 of the trailing blade drive lever 52 and the link mechanism described above. do.

FIG. 6B schematically shows a state in which the leading blades 21 to 24 and the trailing blades 25 to 28 are moving in the +Z direction. As shown in FIG. 6B, an exposure gap E is formed between the leading blade 21 and the following trailing blade 28, and this gap E moves in the opening S of the main plate 10 in the +Z direction, Exposure to the image sensor is performed.

The leading blade drive lever 51 hits the damper 17 and stops, and then the trailing blade drive lever 52 hits the damper 18 and stops, completing the exposure operation. FIG. 6C schematically shows the state at this time.

As described above, the leading blade drive lever 51 is charged by the cam member 61 to hold the leading blade driving section 513 at the position shown in FIG. 6A (referred to as the drive start position). Thereafter, when the electromagnetic attraction by the leading blade electromagnet 91 is released, the leading blade drive lever 51 rotates clockwise in FIG. 6A around the leading blade drive shaft 11, and the leading blade driving section 513 is moved to the position shown in FIG. 6C. (referred to as the drive end position). The leading blade drive unit 513 that has moved to the drive end position hits the damper 17, and the impact at the time of collision is reduced to some extent by the damper 17. However, the impact when the leading blade drive unit 513 hits the damper 17 is transmitted to the leading blade arms 31, 32, the leading blades 21 to 24, or members adjacent thereto, causing these members to bend or vibrate. It is conceivable that this may cause a decrease in the durability of the member and a decrease in the quality of the captured image.

From this point of view, in this embodiment, the impact reduction mechanism 200 for reducing the impact that cannot be completely reduced by the damper 17 is arranged on the +Z direction side of the leading blade arm 31. That is, the impact reducing mechanism 200 is disposed at a position where the leading blade arm 31 that moves due to impact can come into contact when the leading blade driving portion 513 of the leading blade driving lever 51 stops at the drive end position shown in FIG. 6C.

FIG. 7 is a perspective view showing this impact reduction mechanism 200. As shown in FIG. 7, the impact reduction mechanism 200 includes an elastic plate member 210 formed by bending an elongated plate member, and a rectangular parallelepiped-shaped buffer member 250 housed inside the elastic plate member 210. . The elastic plate member 210 of this embodiment is formed of a thermoplastic resin such as polyetheretherketone (PEEK) or polyacetal (POM), and is directed in the Z direction (first direction) in which the leading blades 21 to 24 move as a whole. It is configured so that it can be elastically deformed in the direction of Further, the buffer member 250 is made of, for example, elastic rubber.

FIG. 8A is a rear view showing the elastic plate member 210, and FIG. 8B is a bottom view. As shown in FIGS. 8A and 8B, the elastic plate member 210 includes a first elastic portion 211 having a larger width along the Z direction, and a second elastic portion 211 having a smaller width along the Z direction than the first elastic portion 211. It includes an elastic part 212. The first elastic part 211 includes a plate piece 220 extending along the X direction, a plate piece 221 extending from the +X direction side end of the plate piece 220 in the +Z direction, and a plate piece 221 extending from the +Z direction side end of the plate piece 221. It is composed of a plate piece 220 and a plate piece 222 extending in parallel. The second elastic part 212 includes a plate piece 230 that extends along the X direction, a plate piece 231 that curves in an arc shape from the -X direction side end of the plate piece 230, and a +Z direction side end of the plate piece 231. It is composed of a plate piece 230 and a plate piece 232 extending in parallel from the section.

An opening 240 opened in the +Z direction is formed between the plate piece 222 of the first elastic part 211 and the plate piece 232 of the second elastic part 212. The plate piece 220 of the first elastic part 211 is located closer to the -Z direction than the plate piece 230 of the second elastic part 212, and the plate piece 220 of the first elastic part 211 and the second elastic part It is connected to the plate piece 230 of 212 by a plate piece 241 extending diagonally.

By arranging such an elastic plate member 210 at a position where it can be contacted by the leading blade arm 31 that moves due to the impact when the leading blade driving portion 513 of the leading blade driving lever 51 stops, the leading blade arm 31 By contacting the elastic plate member 210 and elastically deforming the elastic plate member 210, the impact can be absorbed by the elastic plate member 210 and the impact applied to the leading blade arm 31 can be reduced.

Here, in this embodiment, the width in the Z direction of the first elastic part 211 located far from the support shaft 41 is increased, and the width in the Z direction of the second elastic part 212 located close to the support shaft 41 is increased. I'm keeping it small. When the leading blade arm 31 bends or vibrates due to the impact when the leading blade drive unit 513 stops, the portion of the leading blade arm 31 closer to the spindle 41 changes in the rotation direction earlier than the portion farther from the spindle 41. move to. Therefore, as described above, the width in the Z direction of the second elastic part 212 that is in contact with the portion of the elastic plate member 210 that is close to the support shaft 41 of the leading blade arm 31 is adjusted from the support shaft 41 of the leading blade arm 31. By making the width in the Z direction of the first elastic part 211 smaller than the width of the first elastic part 211 with which the far part contacts, it is possible to bring the leading blade arm 31 from a part close to the support shaft 41 to a part far from the support shaft 41 into contact with the elastic plate member 210 almost simultaneously. Therefore, the impact when the leading blade arm 31 hits the elastic plate member 210 can be more effectively reduced.

Further, in this embodiment, since the buffer member 250 made of rubber or the like is arranged inside the first elastic part 211 of the elastic plate member 210, the first elastic part 211 is elastically deformed as described above. At this time, the shock can be further absorbed by the buffer member 250 by bringing the first elastic portion 211 into contact with the inner buffer member 250 to elastically deform the buffer member 250. Therefore, the impact generated when the leading blade driving portion 513 of the leading blade driving lever 51 stops at the drive end position can be further reduced by the buffer member 250, and the durability of the blade driving device 1 can be further improved. In this case, the elastic plate member 210 is preferably made of a harder material than the buffer member 250 in order to disperse and absorb the impact by both the elastic plate member 210 and the buffer member 250.

In the example described above, the opening 240 is formed between the plate piece 222 of the first elastic part 211 and the plate piece 232 of the second elastic part 212 of the elastic plate member 210. As shown, the plate piece 222 of the first elastic part 211 and the plate piece 232 of the second elastic part 212 are connected, and the plate piece 221 of the first elastic part 211 is opened in the X direction. An opening 340 may be formed. By forming such an opening, the elasticity of the elastic plate member 210 in the Z direction can be increased, so that the impact absorption effect of the elastic plate member 210 is enhanced.

In the embodiment described above, the elastic plate member 210 is made of thermoplastic resin, but the material of the elastic plate member 210 is not limited to this. For example, the elastic plate member 210 may be made of a metal such as phosphor bronze. You may. In this case, if the elastic plate member 210 is made of the above-mentioned thermoplastic resin such as PEEK or POM, the elasticity of the elastic plate member can be increased while reducing the thickness of the elastic plate member, and the impact absorption effect can be enhanced.

Furthermore, although the impact reduction mechanism 200 in the above-described embodiment is arranged at a position where the leading blade arm 31 can come into contact with it, the impact reducing mechanism 200 can be connected to the leading blade 21, the leading blade arm 32, and the leading blades 22 to 24. The impact on these members may be reduced by placing them in a position where they can be contacted. Furthermore, such a shock reduction mechanism 200 may be applied to the rear blade arms 33, 34 and the rear blades 25-28.

As described above, according to the first aspect of the present invention, a blade driving device is provided that can effectively reduce the impact that occurs when the blade stops. This blade drive device includes a base plate provided with an opening, a drive shaft extending from the base plate, a support shaft extending from the base plate coaxially with the drive shaft, and a blade arm configured to be rotatable about the support shaft. a blade connected to the blade arm and movable to open and close the opening; a blade drive lever having a blade drive unit connected to the blade arm; and an elastic blade that is elastically deformable in a first direction. The device includes a plate member and a buffer member disposed inside the elastic plate member and elastically deformable in the first direction. The blade drive lever is configured to rotate around the drive shaft and move the blade drive unit from a drive start position to a drive end position. The elastic plate member is arranged at a position where the blade arm or the blade can come into contact with the blade arm or the blade when the blade drive portion of the blade drive lever stops at the drive end position.

According to such a configuration, the blade arm or the blade that moves due to the impact generated when the blade drive portion of the blade drive lever stops at the drive end position is brought into contact with the elastic plate member, and the elastic plate member is elastically deformed to reduce the impact. can be absorbed by the elastic plate member, and the impact applied to the blade arm or blade can be reduced. Further, when the elastic plate member is elastically deformed, the shock can be absorbed by the buffer member by bringing the elastic plate member into contact with a buffer member disposed inside and causing the buffer member to elastically deform. Therefore, the shock generated when the blade drive portion of the blade drive lever stops at the drive end position can be reduced by the buffer member, and the durability of the blade drive device can be improved.

The elastic plate member includes a first elastic portion and a first elastic portion that is located closer to the spindle than the first elastic portion and has a width along the first direction that is smaller than the first elastic portion. It may have two elastic parts. In this case, it is preferable that the buffer member is disposed inside the first elastic portion of the elastic plate member. In this way, the width of the second elastic part of the elastic plate member that is in contact with the part close to the blade arm or the support shaft of the blade is determined by the width of the first elastic part that is in contact with the part of the elastic plate member that is far from the blade arm or the support axis of the blade. By making it smaller than the width, it is possible to contact the elastic plate member almost simultaneously from the part close to the support shaft of the blade arm or the blade to the part far away from the support shaft, making the impact more effective when the blade arm or blade hits the elastic plate member. can be reduced.

An opening opened in the first direction may be provided between the first elastic part and the second elastic part of the elastic plate member. Further, the first elastic portion of the elastic plate member may be provided with an opening that is open in a second direction perpendicular to the first direction. By providing such an opening in the elastic plate member, the elasticity of the elastic plate member in the first direction can be increased, thereby increasing the impact absorption effect of the elastic plate member.

The elastic plate member may be made of thermoplastic resin or metal. In particular, when the elastic plate member is made of thermoplastic resin, the elasticity of the elastic plate member can be increased while reducing the thickness of the elastic plate member, and the impact absorption effect can be enhanced. Examples of such thermoplastic resins include polyetheretherketone and polyacetal.

In addition, in order to disperse and absorb the impact generated when the blade drive portion of the blade drive lever stops at the drive end position by both the elastic plate member and the buffer member, the elastic plate member should be larger than the buffer member. Preferably, it is made of a hard material.

According to a second aspect of the present invention, the blade driving device includes the blade driving device described above, and an imaging device disposed on a surface on which light transmitted through the opening provided in the base plate of the blade driving device forms an image. 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 11 Leading blade drive shaft 12 Trailing blade driving shaft 13 Camshaft 14, 15 Arc groove 17, 18 Damper 21-24 Leading blade 25-28 Trailing blade 31, 32 Leading blade arm 33, 34 Trailing blade arm 41 to 44 Support shaft 51 Leading blade drive lever 52 Trailing blade driving lever 53 Leading blade driving spring 54 Trailing blade driving spring 61 Cam member 91 Leading blade electromagnet 92 Trailing blade electromagnet 200 Impact reduction mechanism 210 Elastic plate member 211 First elastic part 212 Second elastic portion 220 to 222, 230 to 232, 241 Plate piece 240 Opening 250 Buffer member 513 Leading blade drive unit S Opening

Claims (9)

A base plate with an opening,
a drive shaft extending from the base plate;
a support shaft extending coaxially with the drive shaft from the base plate;
a blade arm configured to be rotatable about the support shaft;
a blade connected to the blade arm and movable to open and close the opening;
A blade drive lever having a blade drive unit connected to the blade arm, the blade drive being configured to rotate around the drive shaft and move the blade drive unit from a drive start position to a drive end position. lever and
an elastic plate member capable of elastic deformation in a first direction, the elastic plate member being disposed at a position where the blade arm or the blade can come into contact with the blade arm or the blade when the blade drive portion of the blade drive lever stops at the drive end position; an elastic plate member,
a buffer member disposed inside the elastic plate member and elastically deformable in the first direction;
Vane drive device. The elastic plate member is
a first elastic part;
a second elastic part that is located closer to the support shaft than the first elastic part and has a width along the first direction that is smaller than the first elastic part;
The blade drive device according to claim 1. The blade drive device according to claim 2, wherein the buffer member is arranged inside the first elastic portion of the elastic plate member. The blade drive device according to claim 2 or 3, wherein an opening opened in the first direction is provided between the first elastic part and the second elastic part of the elastic plate member. . The blade drive device according to claim 2 or 3, wherein the first elastic portion of the elastic plate member is provided with an opening opened in a second direction perpendicular to the first direction. The blade drive device according to any one of claims 1 to 5, wherein the elastic plate member is made of thermoplastic resin or metal. The blade drive device according to claim 6, wherein the elastic plate member is made of polyetheretherketone or polyacetal. The blade drive device according to any one of claims 1 to 7, wherein the elastic plate member is made of a harder material than the buffer member. The blade drive device according to any one of claims 1 to 8,
An imaging device, comprising: an imaging element disposed on a surface on which light transmitted through the aperture provided in the base plate of the blade driving device forms an image.

Images