Shutter device and imaging device

Abstract

To provide a shutter device that can change the curtain speed without using a dedicated actuator.SOLUTION: A shutter device (202) has: two blade groups (4, 5) that open and close an opening for exposure; two driving members (7, 8) that individually drive the two blade groups between an open position and a closed position of the opening; two cam gears (22, 23) that individually move the two driving members; and two locking members (9, 10) that can individually lock the two driving members. A first photographic phase in a first mode and a second photographic phase in a second mode are made different from each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a shutter device and an imaging device. [Background technology]

[0002] Typically, the curtain speed of a focal plane shutter used in an imaging device such as a digital single-lens reflex camera or a mirrorless camera cannot be changed after being adjusted to a predetermined value during assembly.

[0003] Patent Document 1 discloses an imaging device that can adjust the curtain speed by combining electromagnetic force and spring force. Patent Document 2 discloses an imaging device that can adjust the curtain speed by combining power from a motor and spring force. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2018 / 230170 [Patent Document 2] International Publication No. 2018 / 230172 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the imaging devices disclosed in Patent Documents 1 and 2 use dedicated actuators such as electromagnetic drivers and motors to adjust the curtain speed, which increases costs.

[0006] SUMMARY OF THE INVENTION The present invention provides a shutter device and an image pickup device that are capable of changing the curtain speed without using a dedicated actuator. [Means for solving the problem]

[0007] A shutter device according to one aspect of the present invention includes two blade sets that open and close an exposure opening, two drive members that drive the two blade sets between an open position and a closed position of the opening, two cam gears that move the two drive members, respectively, and two locking members that can lock the two drive members, respectively. a driving auxiliary member capable of pushing one of the two driving members; In the first mode, This is the phase of one of the two cam gears in the rotation direction during shooting. In the first imaging phase and the second mode This is the phase of one of the two cam gears in the rotation direction during shooting. The second imaging phase is different. The auxiliary driving member does not push one of the two driving members in the first photographing phase, and pushes one of the two driving members in the second photographing phase. do.

[0008] Other objects and features of the present invention will be described in the following embodiments. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a shutter device and an imaging device that are capable of changing the curtain speed without using a dedicated actuator. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of an imaging device according to an embodiment of the present invention. [Figure 2] FIG. 1 is a block diagram of an imaging apparatus according to an embodiment of the present invention. [Figure 3] FIG. 2 is an exploded perspective view of the shutter device according to the embodiment. [Figure 4] FIG. 2 is a plan view of the shutter device in the present embodiment in a standby state for photographing. [Figure 5] FIG. 2 is a perspective view of a main part of the shutter device according to the embodiment. [Figure 6] 10 is a timing chart in the electronic front-curtain shooting mode in this embodiment. [Figure 7] FIG. 2 is a plan view of the shutter device in a running standby state in the electronic front-curtain shooting mode in the present embodiment. [Figure 8] FIG. 10 is a plan view of the shutter device at the start of a set operation in electronic front-curtain shooting mode in this embodiment. [Figure 9]FIG. 10 is a plan view of the shutter device when the rear curtain setting operation is completed in electronic front-curtain photography mode in the present embodiment. [Figure 10] 10 is a timing chart in the mechanical first-curtain shooting mode in this embodiment. [Figure 11] FIG. 2 is a plan view of the shutter device in a running standby state in mechanical front-curtain photography mode in the present embodiment. [Figure 12] FIG. 10 is a plan view of the shutter device at the start of a set operation in mechanical front-curtain photography mode in this embodiment. [Figure 13] FIG. 10 is a plan view of the shutter device during a setting operation in mechanical first-curtain photography mode in the present embodiment. [Figure 14] 5A and 5B are diagrams illustrating a cam shape of a rear cam gear in the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0012] First, with reference to FIG. 1, the external configuration of an image capture device 100 equipped with a shutter device (focal plane shutter) according to this embodiment will be described. FIG. 1 is a perspective view of the image capture device 100. On the top surface of the image capture device 100, a power button 110, a release button 130, and an accessory shoe 140 for attaching a photographic accessory such as a flash device are provided. A lens mount 150 is an attachment portion for a lens device (interchangeable lens) (not shown). Because the image capture device 100 is a mirrorless type image capture device that does not use a reflex mirror, the shutter curtain is open in the shooting standby state to display a live view. Therefore, as shown in FIG. 1, when the lens device is removed, the imaging surface of the image sensor 203 is exposed.

[0013] Next, the internal configuration of the imaging device 100 will be described with reference to FIG. 2. FIG. 2 is a block diagram of the imaging device 100. A shutter device (focal plane shutter) 202 is provided between an imaging lens 201, which forms an image of light from a subject on a photographing optical path, and an imaging element 203, such as a CMOS image sensor, and adjusts the exposure time of the imaging element 203 in conjunction with the operation of an electronic front curtain of the imaging element 203. The imaging element 203 photoelectrically converts the subject image (optical image) formed by the imaging lens (imaging optical system) 201 provided in a lens device. An analog image signal output from the imaging element 203 is converted into a digital signal by an AFE (Analog Front End) 204. A DSP (Digital Signal Processor) 205 performs various image processing, compression / decompression processing, and the like on the digital image signal output from the AFE 204. A recording medium 206 records the image data processed by the DSP 205. The display unit 207 uses a liquid crystal display (LCD) or the like and displays captured images, various menu screens, etc. A TG (Timing Generator) 208 supplies a drive signal to the image sensor 203. A RAM 210 is connected to the DSP 205 and temporarily stores image data, etc. A shutter drive circuit 211 drives the shutter device 202. A CPU 209 controls the AFE 204, DSP 205, TG 208, and shutter drive circuit 211. A lens control means 212 outputs lens information such as the focal length of the imaging lens 201, the aperture diameter, the pupil diameter, and the distance between the pupil and the image sensor 203 to the CPU 209, and drives the aperture, lens, etc. according to the control of the CPU 209.

[0014] Next, the shutter device 202 will be described with reference to Figures 3(a) and (b), Figures 4(a) and (b), and Figures 5(a) and (b). Figures 3(a) and (b) are exploded perspective views of the shutter device 202. Figure 3(a) is an exploded perspective view of the shutter device 202 as seen from the side where the image sensor 203 is attached (the image sensor side). Figure 3(b) is an exploded perspective view as seen from the side where the lens device is attached (the subject side). Figures 4(a) and (b) are plan views of the shutter device 202 in a shooting standby state, with Figure 4(a) showing a plan view of the shooting standby state as seen from the image sensor side and Figure 4(b) showing a plan view of the shooting standby state as seen from the subject side. 5(a) and (b) are perspective views of the main parts of the shutter device 202, with Fig. 5(a) showing the configuration of the leading driving member 7 and leading cam gear 22, and Fig. 5(b) showing the configuration of the rear driving member 8, rear driving auxiliary member 91, and rear cam gear 23. The leading cam gear 22 and the rear cam gear 23 are two cam gears that move (rotate) the leading driving member 7 and the rear driving member 8, respectively.

[0015] A partition plate 2 and a cover plate 3 are attached in this order at a specified interval to the object side of the shutter base plate 1. Similar shaped apertures 1a, 2a, and 3a are formed in the three plate members of the shutter base plate 1, partition plate 2, and cover plate 3, and a rectangular opening (exposure aperture) formed by overlapping these three apertures defines the light beam passing through the shutter. Two blade chambers are formed between these three plate members, and within these blade chambers, shutter blades consisting of light-shielding blades and blade arms are individually arranged as a leading blade group 4 and a trailing blade group 5. The leading blade group 4 and the trailing blade group are the two blade groups that open and close the exposure aperture.

[0016] To increase the strength of the shutter base plate 1 and to tighten the various metal shafts, a metal auxiliary base plate 6 is fastened to the shutter base plate 1 with screws. Shafts 6a, 6b, 6c, 6d, 6e, 6f, and 6m are erected on the auxiliary base plate 6 on the imaging element side. A leading drive member 7, a trailing drive member 8, a trailing drive auxiliary member 91, a leading locking member 9, and a trailing locking member 10 are rotatably attached to the shafts 6a, 6b, 6c, and 6d, respectively. The trailing drive member 8 and the trailing drive auxiliary member 91 are both attached to the shaft 6b and have the same center of rotation. A leading drive source 24 and a trailing drive source 25 (both DC motors) are fastened to the object side of the auxiliary base plate 6 with screws, respectively.

[0017] A gear base plate 26 is fastened with screws to the subject side of the auxiliary base plate 6. The leading cam gear 22 and the rear cam gear 23 are rotatably attached to shafts 26a and 26b, respectively, which are erected on the imaging element side of the gear base plate 26. A leading reduction gear group 27 is rotatably supported on shafts 26c and 26e on the imaging element side of the gear base plate 26, and a rear reduction gear group 28 is rotatably supported on shafts 26d and 26f. The leading reduction gear group 27 and the leading cam gear 22 are connected to the output shaft 24a of the leading drive source 24. The rear reduction gear group 28 and the rear cam gear 23 are similarly connected to the output shaft 25a of the rear drive source 25. In this way, the torque of the leading drive source 24 and the rear drive source 25 is transmitted to the leading cam gear 22 and the rear cam gear 23, respectively. The front drive source 24 and the rear drive source 25 can be used in either forward or reverse rotation, and here, the direction in which the front cam gear 22 and the rear cam gear 23 rotate counterclockwise in FIG. 4(a) is defined as forward rotation.

[0018] Hereinafter, the rotation directions will be defined with reference to Figure 4(a). The leading driving member 7 is biased counterclockwise by the biasing force of a leading driving spring 12. The rear driving member 8 is biased counterclockwise by the biasing force of a rear driving spring 13. The leading driving member 7 and the rear driving member 8 are two driving members that drive the leading blade group 4 and the rear blade group 5, respectively, between the opening position and the closing position of the aperture.

[0019] The rear drive auxiliary member (drive auxiliary member) 91 is biased counterclockwise by the biasing force of the rear drive auxiliary spring 92, and is a boost lever configured to be able to push (push) the rear drive member 8, one of the two drive members. The rear drive member 8 is configured to be able to operate by receiving a counterclockwise push from the rear drive auxiliary member 91, and whether or not it is pushed varies depending on the shooting mode. During the setting operation, the front drive member 7 is rotated clockwise by the front cam gear 22 against the biasing force of the front drive spring 12. The rear drive member 8 and the rear drive auxiliary member 91 are rotated clockwise by the rear cam gear 23 against the biasing forces of the rear drive spring 13 and the rear drive auxiliary spring 92. 11, the leading driving member 7 and the rear driving member 8 are locked by the locked portions 7a and 8a provided on the leading driving member 7 and the rear driving member 8 engaging with the leading locking member 9 and the rear locking member 10, respectively. In other words, the leading locking member 9 and the rear locking member 10 are two locking members that can lock the leading driving member 7 and the rear driving member 8, respectively. The locking release members 51 and 52, together with the electromagnetic actuator base 50, form an electromagnetic actuator, and the leading locking member 9 and the rear locking member 10 can be actuated by the rotation of the locking release members 51 and 52, respectively.

[0020] The leading driving member 7 and the rear driving member 8 are provided with a leading driving pin 7b and a rear driving pin 8b, respectively. These pins pass through three pairs of elongated holes 1b and 1c, 6g and 6h, and 3b and 3c in the shutter base plate 1, auxiliary base plate 6, and cover plate 3, and engage with the elongated holes 4c and 5c in the blade arms 4a and 5a. Rollers 14 and 15 are rotatably attached to the leading driving member 7. Rollers 16 and 17 are rotatably attached to the rear driving member 8. A roller 93 is rotatably attached to the rear driving auxiliary member 91. The leading cam gear 22 appropriately sets the leading driving member 7 via the rollers 14 and 15. The rear driving member 8 is appropriately set via the rollers 16 and 17, and the rear driving auxiliary member 91 is appropriately set via the rollers 93, both of which are performed by the rear cam gear 23.

[0021] In this embodiment, the leading cam gear 22 is formed with cam surfaces 22a and 22b, and the rear cam gear 23 is formed with cam surfaces 23a, 23b, and 23c. The leading cam gear 22 sequentially contacts rollers 14 and 15 attached to the leading driving member 7, roller 93 attached to the rear driving auxiliary member 91, and rollers 16 and 17 attached to the rear driving member 8, performing the setting operation. This averages out the amount of rotation of the leading driving member 7, rear driving member 8, rear driving auxiliary member 91, and the leading cam gear 22 and rear cam gear 23 during the setting operation, thereby reducing the maximum load during the setting operation. Depending on the tolerances of the related components, the leading driving member 7, rear driving member 8, and rear driving auxiliary member 91 may not be able to be set within the allowable set position. In such cases, the set positions of the leading driving member 7, rear driving member 8, and rear driving auxiliary member 91 can be adjusted by replacing rollers 15, 17, and 93.

[0022] The blade phase detection means 29, blade phase detection means 30, and cam phase detection means 31 are non-contact optical phase detection means and are attached to the holding base plate 11 arranged on the imaging element side of the auxiliary base plate 6. In this embodiment, photointerrupters are used as the blade phase detection means 29, blade phase detection means 30, and cam phase detection means 31. On the other hand, the cam phase detection means 32 is a contact-type phase detection means. The blade phase is detected by determining the light-blocking state of the blade phase detection means 29 and blade phase detection means 30 by the detection target portions 7f and 8f of the leading driving member 7 and the rear driving member 8. The cam phase of the leading cam gear 22 is detected by determining the light-blocking state of the cam phase detection means 31 by the detection target portion 22c. The cam phase of the rear cam gear 23 is detected by determining the position where a phase detection contact (not shown) attached to the rear cam gear 23 contacts the cam phase detection means 32.

[0023] In this embodiment, the leading blade group 4 and the trailing blade group 5 each include two sets of blade arms 4a, 4b and 5a, 5b, and four sets of blades 4d, 4e, 4f, 4g and 5d, 5e, 5f, 5g. The leading blade group 4 has two blade arms 4a, 4b pivotally mounted on shafts 6i, 6j on the subject side of the auxiliary base plate 6. The four blades 4d, 4e, 4f, 4g are pivotally supported on the blade arms 4a, 4b via a connecting shaft 33. An elongated hole 4c is formed in the blade arm 4a, and a leading drive pin 7b of the leading drive member 7 is engaged therein. The trailing blade group 5 has two blade arms 5a, 5b pivotally mounted on shafts 6k, 6l on the subject side of the auxiliary base plate 6. The four blades 5d, 5e, 5f, and 5g are pivotally supported on the blade arms 5a and 5b via a connecting shaft 33. An elongated hole 5c is formed in the blade arm 5a, and a rear drive pin 8b of the rear drive member 8 is engaged with the elongated hole 5c.

[0024] Next, the shooting operation during continuous shooting in this embodiment will be described with reference to Figures 4 to 14. The shooting sequence in this embodiment is divided into two modes: an electronic first-curtain shooting mode (second mode) and a mechanical first-curtain shooting mode (first mode). Here, the mechanical first-curtain shooting mode is a mode in which exposure is performed using two slit forming portions of each of the two blade groups, and the electronic first-curtain shooting mode is a mode in which exposure is performed using an electronic shutter of the imaging device and one slit forming portion of the two blade groups.

[0025] Fig. 6 is a timing chart showing the operation timing of each component of the shutter device 202 and the image sensor 203 in the electronic front-curtain shooting mode. Fig. 10 is a timing chart showing the operation timing of each component of the shutter device 202 and the image sensor 203 in the mechanical front-curtain shooting mode. States (1) to (11) in Fig. 6 and states (1) to (12) in Fig. 10 correspond to the respective operation states described below.

[0026] First, the electronic front-curtain shooting mode will be described. Figures 4(a) and 4(b) are plan views of the shutter device 202 in a shooting standby state. Figure 7 is a plan view of the shutter device 202 in a run standby state after the rear curtain has been released from setting. Figure 8 is a plan view of the shutter device 202 in a state immediately before the setting operation after the rear curtain has completed running. Figure 9 is a plan view of the shutter device 202 in a state where the rear curtain setting operation has been completed.

[0027] In the shooting standby state (state (1) in FIG. 6), the shutter device 202 is in a state in which the travel of the front driving member 7 has been completed, as shown in FIGS. 4(a) and (b). Meanwhile, the rear driving member 8 is held by the cam top (cam top position) of the rear cam gear 23, and is in an overcharged state in which there is a gap 8e between the locked portion 8a of the rear driving member 8 and the locking portion 10a of the rear locking member 10. Because the front blade group 4 and the rear blade group 5 are retracted from the exposure opening, the subject light beam passes through the exposure opening. In the imaging device 100, a live view imaging operation is performed, and the subject image incident on the image sensor 203 is displayed on the display unit 207.

[0028] When the release button 130 of the imaging device 100 is pressed, a release operation is initiated (state (2) in FIG. 6 ), and the rear driving member 8 is released from the set position. Power is supplied to the rear driving source 25 in the forward direction, causing the rear cam gear 23 to rotate counterclockwise via the rear reduction gear group 28. The roller 17 moves away from the cam surface 23b of the rear cam gear 23, and the roller 93 moves away from the cam surface 23c of the rear cam gear 23. The rear driving member 8, the rear drive auxiliary member 91, and the rear blade group 5 rotate slightly counterclockwise together, and the overcharged state is released. At this time, the gap 8e between the locked portion 8a of the rear driving member 8 and the locking portion 10a of the rear locking member 10 disappears, and the locked portion 8a of the rear driving member 8 engages with the locking portion 10a of the rear locking member 10, causing the rear driving member 8 to stop at the travel start position. Further, under the bias of the rear drive auxiliary spring 92, the locked portion 91a of the rear drive auxiliary member 91 is stopped in a state where it is pushing against the locked portion 8a of the rear drive member 8. After the rear cam gear 23 retreats (cam bottoms) from the travel range of the rear drive member 8 and the rear drive auxiliary member 91, the cam phase detection means 32 detects the second photographing phase shown in Fig. 6 and stops the rear drive source 25, resulting in a travel standby state as shown in Fig. 7 (state (3) in Fig. 6).

[0029] After all pixels of the image sensor 203 are reset (state (4) in FIG. 6), electronic front-curtain scanning begins (state (5) in FIG. 6). The electronic front-curtain scanning has a scanning pattern that matches the traveling characteristics of the rear blade group 5 when the rear drive member 8 is pushed by the rear drive auxiliary member 91. After a time corresponding to the set shutter speed has elapsed, the lock release member 52 shown in FIG. 3(a) hits the pushing portion 10b of the rear locking member 10. This causes the rear locking member 10 to rotate counterclockwise around the shaft 6d, releasing the engagement of the locked portion 8a of the rear drive member 8 (state (6) in FIG. 6). Then, from the traveling standby state shown in FIG. 7, the rear drive member 8 and the rear drive auxiliary member 91 are rapidly rotated counterclockwise around the shaft 6b by the biasing forces of the rear drive spring 13 and the rear drive auxiliary spring 92. The rotation speed at this time is faster than when the rear drive member 8 is not pushed by the rear drive auxiliary member 91. As the rear driving member 8 rotates, the rear driving pin 8b rotates the blade arm 5a counterclockwise, causing the rear blade group 5 to cover the exposure opening. The rear driving auxiliary member 91 comes into contact with the shaft 6m midway and stops.

[0030] Thereafter, the rear driving member 8 continues to rotate without being pushed by the rear driving auxiliary member 91. The rear driving auxiliary member 91 pushes the rear driving member 8 only in a portion of its rotation because a predetermined curtain speed can be achieved with less energy than if it were pushed over the entire rotation range. As the exposure operation continues, the rear driving pin 8b abuts against a stopping member (not shown) when the slit-forming edge (slit-forming portion) 5h of the rear blade 5d of the rear blade group 5 retreats below the exposure opening, and the rear driving member 8 is stopped. Figure 8 shows the blade travel completion state achieved in this way. When the travel of the rear blade group 5 ends and the image sensor 203 is completely shaded, charge readout scanning begins (state (7) in Figure 6).

[0031] A predetermined time after the completion of the travel of the rear blade group 5, current is applied to the front drive source 24 in the forward direction (state (8) in FIG. 6), causing the front cam gear 22 to rotate counterclockwise around the shaft 26a. Accordingly, the front drive member 7 comes into contact with the front cam gear 22 and is rotated clockwise around the shaft 6a against the biasing force of the front drive spring 12. A predetermined time after the start of current application to the front drive source 24, current is applied to the rear drive source 25 in the forward direction (state (9) in FIG. 6) before the front drive member 7 reaches the cam top of the front cam gear 22, causing the rear cam gear 23 to rotate counterclockwise around the shaft 26b. Accordingly, the rear drive auxiliary member 91 comes into contact with the rear cam gear 23 and is rotated clockwise around the shaft 6b against the biasing force of the rear drive auxiliary spring 92. Subsequently, the rear driving member 8 comes into contact with the rear cam gear 23 and is rotated clockwise around the shaft 6b against the biasing force of the rear driving spring 13.

[0032] Meanwhile, the movements of the leading blade group 4 and the trailing blade group 5 at this time are as follows. The leading drive pin 7b of the leading driving member 7 rotates the blade arm 4a clockwise, and blades 4d, 4e, 4f, and 4g move upward while reducing their mutual overlap. The rear drive pin 8b of the rear driving member 8 rotates the blade arm 5a clockwise, and blades 5d, 5e, 5f, and 5g move upward while increasing their mutual overlap. When the leading driving member 7 passes the cam top of the leading cam gear 22 and continues to rotate, the locked portion 7a of the leading driving member 7 engages with the locking portion 9a of the leading locking member 9, causing the leading driving member 7 to stop at the travel start position. The leading cam gear 22 continues to rotate, but after the leading driving member 7 retreats from the travel range (cam bottom) (i.e., reaches the cam bottom), the cam phase detection means 31 detects the stop phase and stops the supply of electricity to the leading drive source 24.

[0033] Similarly, the rear driving member 8 continues to rotate as it passes through the cam top of the rear cam gear 23, and the locked portion 8a of the rear driving member 8 engages with the locking portion 10a of the rear locking member 10, causing the rear driving member 8 to stop at the travel start position. The rear cam gear 23 continues to rotate further, but after it retreats from the travel range of the rear driving member 8 (cam bottom), when the cam phase detection means 32 detects the stop phase, it stops supplying electricity to the rear driving source 25 (state (10) in FIG. 6).

[0034] FIG. 9 shows the state after the rear curtain setting operation is completed. From this point, the leading driving member 7 and the leading blade group 4 begin to travel in order to transition to the live view state. The lock-release member 51 shown in FIG. 3(a) strikes the pushing portion 9b of the leading locking member 9, causing the leading locking member 9 to rotate counterclockwise around the shaft 6c and disengage the locked portion 7a of the leading driving member 7. The biasing force of the leading driving spring 12 then causes the leading driving member 7 to rapidly rotate counterclockwise around the shaft 6a. This causes the leading driving pin 7b to rotate the blade arm 4a counterclockwise, causing the leading blade group 4 to open the exposure opening. When the slit-forming edge (slit-forming portion) 4h of blade 4d of the leading blade group 4 retreats below the exposure opening, the leading driving pin 7b abuts against a stopping member (not shown), stopping the leading driving member 7. The leading blade group 4 then completes its travel and enters the travel standby state shown in FIG. 4.

[0035] After the leading blade group 4 has completed its travel, the leading drive source 24 is stopped, and the image sensor 203 starts a live view imaging operation, and preparations for photographing the next frame are made (state (10) in FIG. 6). When preparations for photographing the next frame are complete, the state returns to state (1) in FIG. 6, and thereafter, the series of photographing operations from state (1) to state (10) in FIG. 6 are repeated.

[0036] Next, the mechanical front-curtain photography mode will be described. Fig. 4 shows the shutter device 202 in a photography standby state. Fig. 11 is a plan view of the shutter device 202 in a travel standby state after the rear curtain has been released. Fig. 12 is a plan view of the shutter device 202 in a state immediately before the setting operation after the rear blade travel has completed. Fig. 13 is a plan view of the shutter device 202 in a state when the rear cam gear 23 is in the cam bottom position of the cam surface 23c during the setting operation. Figs. 14(a) and (b) are diagrams showing the cam shape of the rear cam gear 23, and Fig. 14(a) shows the shape of the cam surface 23c of the rear cam gear 23, corresponding to the cross section AA of the rear cam gear 23 shown in Fig. 14(b).

[0037] In the shooting standby state (state (1) in FIG. 10), the shutter device 202 is in a state in which the travel of the front driving member 7 has been completed, as shown in FIGS. 4(a) and (b). Meanwhile, the rear driving member 8 is held by the cam top of the rear cam gear 23, and is in an overcharged state in which there is a gap 8e between the locked portion 8a of the rear driving member 8 and the locking portion 10a of the rear locking member 10. Because the front blade group 4 and the rear blade group 5 are retracted from the exposure opening, the subject light beam passes through the exposure opening. In the imaging device 100, a live view imaging operation is performed, and the subject image incident on the image sensor 203 is displayed on the display unit 207.

[0038] When release button 130 of imaging device 100 is pressed, the setting and releasing operations of the front curtain and the setting and releasing operation of the rear curtain start (state (2) in FIG. 10 ), and current is supplied to front drive source 24 in the forward direction, causing front cam gear 22 to rotate counterclockwise around shaft 26a. Accordingly, front drive member 7 comes into contact with front cam gear 22 and is rotated clockwise around shaft 6a against the biasing force of front drive spring 12. At the same time, the setting and releasing operation of rear drive member 8 is performed. Current is supplied to rear drive source 25 in the forward direction, causing rear cam gear 23 to rotate counterclockwise via rear reduction gear group 28. Roller 17 separates from cam surface 23b of rear cam gear 23, and rear drive member 8 rotates slightly counterclockwise together with rear blade group 5, thereby releasing the overcharged state. The gap 8e between the locked portion 8a of the rear driving member 8 and the locking portion 10a of the rear locking member 10 disappears, and the locked portion 8a of the rear driving member 8 engages with the locking portion 10a of the rear locking member 10, causing the rear driving member 8 to stop at the travel start position. After the rear cam gear 23 retreats from the travel range of the rear driving member 8 (cam bottom), the cam phase detection means 32 detects the first photographing phase shown in Figure 10 and stops the rear driving source 25, resulting in a travel standby state as shown in Figure 11 (state (3) in Figure 10).

[0039] Meanwhile, the rear drive auxiliary member 91 is held by the cam surface 23c of the rear cam gear 23. When the leading driving member 7 passes the cam top of the leading cam gear 22 and continues to rotate, the locked portion 7a of the leading driving member 7 engages with the locking portion 9a of the leading locking member 9, causing the leading driving member 7 to stop at the travel start position. After that, after the leading cam gear 22 retreats from the travel range of the leading driving member 7 (cam bottom), the cam phase detection means 31 detects the stop phase and stops the leading driving source 24.

[0040] When a predetermined time has elapsed after the first driving source 24 has stopped, the lock release member 51 strikes the pushing portion 9b of the first locking member 9, causing the first locking member 9 to rotate counterclockwise around the shaft 6c and disengage the locked portion 7a of the first driving member 7 (state (5) in FIG. 10). Then, from the travel standby state shown in FIG. 11, the first driving member 7 is rapidly rotated counterclockwise around the shaft 6a by the biasing force of the first driving spring 12. This causes the first driving pin 7b to rotate the blade arm 4a counterclockwise, causing the first blade group 4 to open the exposure opening. As the exposure operation continues, when the slit-forming edge 4h of the blade 4d of the first blade group 4 retreats below the exposure opening, the first driving pin 7b comes into contact with a stopping member (not shown), and the first driving member 7 is stopped. After the time corresponding to the set shutter speed has elapsed, the locking release member 52 hits the pushing portion 10b of the rear locking member 10, causing the rear locking member 10 to rotate counterclockwise around the shaft 6d, thereby releasing the engagement of the locked portion 8a of the rear driving member 8 (state (6) in FIG. 10).

[0041] Then, from the standby state shown in FIG. 11, the rear driving member 8 is rapidly rotated counterclockwise around the shaft 6b by the biasing force of the rear driving spring 13. The rotational speed at this time is slower than when the rear driving member 8 is pushed by the auxiliary rear driving member 91. To prevent uneven exposure, the time-series speed changes of the slit-forming edge 4h and the slit-forming edge 5h are made similar. The operation of the rear driving member 8 causes the rear driving pin 8b to rotate the blade arm 5a counterclockwise. As a result, the rear blade group 5 covers the exposure opening. As the exposure operation continues, when the slit-forming edge 5h of the blade 5d of the rear blade group 5 retreats below the exposure opening, the rear driving pin 8b abuts against a stop member (not shown), stopping the rear driving member 8 (FIG. 12). When the rear blade group 5 stops traveling and the image sensor 203 is completely shielded from light, charge readout scanning begins (state (7) in FIG. 10).

[0042] A predetermined time after the rear blade group 5 has completed its travel, current is applied to the front drive source 24 in the forward direction (FIG. 10(8)), causing the front cam gear 22 to rotate counterclockwise around the shaft 26a. A predetermined time after the start of current application to the front drive source 24, current is applied to the rear drive source 25 in the forward direction (state (9) in FIG. 10), causing the rear cam gear 23 to rotate counterclockwise around the shaft 26b. Accordingly, the roller 93 of the rear drive auxiliary member 91, which had been held by the cam surface 23c, leaves the rear cam gear 23 and starts to rotate counterclockwise (state (10) in FIG. 10). However, immediately after the start of rotation, the locked portion 91a of the rear drive auxiliary member 91 is locked by the locking portion 10a of the rear locking member 10 (FIG. 13). That is, the locked portion 91a can be locked by the rear locking member 10, which is one of the two locking members. Therefore, compared to when the rear drive auxiliary member 91 is rotated until it collides with the shaft 6f, the charge load in the subsequent setting operation can be reduced.

[0043] 10 and 14(a), the cam surface 23c of the rear cam gear 23 has a cam top (a first region corresponding to the cam top position) and a region slightly lower than the cam top (a second region lower than the first region). Just before reaching the state of FIG. 13, the rear drive assist member 91 does not drop directly from the cam top to the locking position, but drops to the locking position from a position slightly lower than the cam top. Therefore, compared to when there is no region slightly lower than the cam top, the amount of rotation required for the rear drive assist member 91 to be locked is smaller, making it easier for the rear drive assist member 91 to be locked by the rear locking member 10.

[0044] As current continues to be applied to the front drive source 24 and the rear drive source 25, the front drive member 7 comes into contact with the front cam gear 22 and is rotated clockwise around the shaft 6a against the biasing force of the front drive spring 12. The rear drive auxiliary member 91 comes into contact with the rear cam gear 23 and is rotated clockwise around the shaft 6b against the biasing force of the rear drive auxiliary spring 92. Subsequently, the rear drive member 8 comes into contact with the rear cam gear 23 and is rotated clockwise around the shaft 6b against the biasing force of the rear drive spring 13.

[0045] Meanwhile, the movements of the leading blade group 4 and the trailing blade group 5 at this time are as follows. The leading driving pin 7b of the leading driving member 7 rotates the blade arm 4a clockwise, and blades 4d, 4e, 4f, and 4g move upward while reducing the overlap between them. Also, the rear driving pin 8b of the rear driving member 8 rotates the blade arm 5a clockwise, and blades 5d, 5e, 5f, and 5g move upward while increasing the overlap between them. When the leading driving member 7 passes the cam top of the leading cam gear 22 and continues to rotate, the locked portion 7a of the leading driving member 7 engages with the locking portion 9a of the leading locking member 9, and the leading driving member 7 stops at the travel start position. The leading cam gear 22 continues to rotate, but after retreating from the travel range of the leading driving member 7 (cam bottom), when the cam phase detection means 31 detects the stop phase, the supply of electricity to the leading driving source 24 is stopped.

[0046] Similarly, the rear driving member 8 continues to rotate as it passes through the cam top of the rear cam gear 23, and the locked portion 8a of the rear driving member 8 engages with the locking portion 10a of the rear locking member 10, causing the rear driving member 8 to stop at the travel start position. The rear cam gear 23 continues to rotate further, but after it retreats from the travel range of the rear driving member 8 (cam bottom), when the cam phase detection means 32 detects the stop phase, it stops supplying electricity to the rear driving source 25 (state (11) in FIG. 10).

[0047] FIG. 9 shows the state after the rear curtain setting operation is completed. From this point, the leading driving member 7 and the leading blade group 4 begin to travel in order to transition to the live view state. The lock-releasing member 51 shown in FIG. 3A strikes the pushing portion 9b of the leading locking member 9, causing the leading locking member 9 to rotate counterclockwise around the shaft 6c and disengage the locked portion 7a of the leading driving member 7. The biasing force of the leading driving spring 12 then causes the leading driving member 7 to rapidly rotate counterclockwise around the shaft 6a. This causes the leading driving pin 7b to rotate the blade arm 4a counterclockwise, causing the leading blade group 4 to open the exposure opening. When the slit-forming edge 4h of blade 4d of the leading blade group 4 retreats below the exposure opening, the leading driving pin 7b abuts against a stopping member (not shown), stopping the leading driving member 7. The leading blade group 4 then completes its travel and enters the travel standby state shown in FIGS. 4A and 4B.

[0048] After the leading blade group 4 has completed its travel, the leading drive source 24 is stopped, and the image sensor 203 starts a live view imaging operation, and preparations for photographing the next frame are made (state (12) in FIG. 10). When preparations for photographing the next frame are complete, the state returns to state (1) in FIG. 10, and thereafter, the series of photographing operations from state (1) to state (12) in FIG. 10 are repeated.

[0049] According to the shutter device 202 of this embodiment, by providing a first shooting phase and a second shooting phase (differentiating the first shooting phase from the second shooting phase), two curtain speeds (fast and slow curtain speeds) can be used without using a dedicated actuator. Preferably, the curtain speed is increased in the electronic front-curtain shooting mode (second mode), and the curtain speeds are adjusted so that the curtain speeds of the front and rear curtains are the same in the mechanical front-curtain shooting mode (first mode) (the curtain speed in the second mode is faster than the curtain speed in the first mode). This makes it possible to increase the X-synchronization speed by increasing the curtain speed in electronic front-curtain shooting while taking advantage of the variable travel curve of the electronic front curtain. Therefore, this embodiment can provide a shutter device and an image capture device that can change the curtain speed without using a dedicated actuator.

[0050] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0051] For example, the electronic front curtain shooting phase, which is the second shooting phase using the rear drive auxiliary member 91, is a phase later than the mechanical front curtain shooting phase, which is the first shooting phase not using the rear drive auxiliary member 91, but this is to eliminate waste in the cam shape and is not limited to this. [Explanation of symbols]

[0052] 4. Fore-wing group (wing group) 5. Rear feather group (feather group) 7. Leading drive member (driving member) 8 rear drive member (drive member) 9 End locking member (locking member) 10 Rear locking member (locking member) 22 Cam gear (cam gear) 23 Rear cam gear (cam gear) 91 Rear drive auxiliary member (drive auxiliary member) 202 Shutter device

Claims

1. two sets of blades for opening and closing an exposure aperture; two drive members for driving the two sets of blades between an open position and a closed position of the opening, respectively; Two cam gears that move the two drive members, respectively; two locking members capable of locking the two drive members, respectively; a drive auxiliary member capable of pushing one of the two drive members, a first photographing phase, which is a phase of one of the two cam gears in a rotation direction during photographing in a first mode, and a second photographing phase, which is a phase of one of the two cam gears in a rotation direction during photographing in a second mode, are made different from each other; The driving auxiliary member is In the first photographing phase, one of the two driving members is not pushed, A shutter device characterized in that, in the second photographing phase, one of the two drive members is pushed.

2. 2. The shutter device according to claim 1, wherein one of the two cam gears has a cam-shaped cam surface that prevents the drive auxiliary member from pushing one of the two drive members in the first shooting phase.

3. 3. The shutter device according to claim 2, wherein the cam surface has a first region corresponding to a cam top position and a second region lower than the first region.

4. 4. The shutter device according to claim 1, wherein the auxiliary drive member has a locked portion that can be locked by one of the two locking members.

5. 5. The shutter device according to claim 1, wherein at least one of the two cam gears has phases in the order of a phase corresponding to a shooting standby state, the first shooting phase, and the second shooting phase in the rotation direction during shooting.

6. 6. The shutter device according to claim 1, wherein the two cam gears set the two drive members from a cam bottom position to a cam top position.

7. A shutter device according to any one of claims 1 to 6; an imaging element that photoelectrically converts an optical image formed through an imaging optical system;

8. the first mode is a mode in which exposure is performed using two slit forming portions of each of the two blade sets, 8. The imaging device according to claim 7, wherein the second mode is a mode in which exposure is performed using an electronic shutter of the imaging device and one of the slit forming portions of the two sets of blades.

9. 8. The image pickup apparatus according to claim 7, wherein the curtain speed in the second mode is faster than the curtain speed in the first mode.

Images