JP6031904B2 - Mount adapter and camera system - Google Patents

Description

  The present invention relates to a mount adapter for mounting a lens having a different mount system to a camera body, and a camera system including the mount adapter.

  An interchangeable lens camera is provided with a mount adapter for mounting a lens with a different mounting method to the camera body. For example, Patent Document 1 proposes a technique in which a wide conversion optical system is arranged on a mount adapter in order to allow an interchangeable lens having a different image circle to be mounted on a camera body and perform appropriate photographing. By using such a mount adapter, even a mirrorless digital camera whose lens mount has been reduced in size in recent years is photographed using an interchangeable lens having a conventional large lens mount. It becomes possible.

  By the way, as a mirrorless type digital camera, shooting is performed using a mechanical shutter provided on the interchangeable lens side. However, when an interchangeable lens not equipped with a shutter is attached or the shutter provided on the interchangeable lens is used as a camera. There has been proposed a system in which photographing is performed using an electronic shutter in an imaging element of a camera body when it cannot be driven in conjunction with the body side. Therefore, a so-called konjac phenomenon that a subject moving at high speed at the time of photographing with an electronic shutter is captured in a distorted state is a problem. Therefore, the applicant has proposed that the mount adapter has a built-in shutter as a light-shielding means, and that shooting using the shutter provided on the mount adapter is performed when shooting using the shutter of the interchangeable lens is not possible.

JP 2010-28328 A

  As this shutter, it is conceivable to apply a lens shutter provided in a conventional lens as it is, but this type of shutter is normally in a fully closed state or a fully open state due to the mechanism. Therefore, the shutter is fully closed or fully opened even when the mount adapter is attached to the camera body or when the mount adapter is detached from the camera body. Therefore, if the shutter is fully closed when the mount adapter is removed from the camera body, this stress is applied when the shutter blades of the exposed shutter are touched or when stress is applied to the shutter blades by wind pressure, etc. As a result, the shutter blade is deformed or the shutter blade is moved from the normal position, and the normal operation of the shutter thereafter may be hindered.

  An object of the present invention is to provide a mount adapter that can prevent damage to the shutter as the light shielding means. The present invention also provides a camera system having such a mount adapter.

The mount adapter of the present invention includes a first lens mount portion that can be attached to a first type lens mount provided on a camera body, and a second lens mount that can be attached to an interchangeable lens having a second type lens mount. a mounting adapter and a part, the interior opening of the mounting adapter comprises a closing operable shutter mechanism, the shutter mechanism is opened the part of the inner opening when the mount adapter is detached from the camera body This configuration can be maintained in a state. The shutter mechanism includes a shutter blade portion for opening and closing an internal opening and a shutter drive portion for driving the shutter blade portion. The shutter drive portion is configured to open the shutter blade portion between a fully closed state and a fully open state. While being driven to an arbitrary opening state, the opening state can be maintained. The shutter driving unit includes a charging unit that drives the shutter blade unit from the fully closed state to the fully opened state, and a charge release unit that releases the charging state of the charging unit and returns the shutter blade unit to the fully closed state. The charging means is configured to be able to stop the charging operation during charging.

  In the present invention, the charging means includes, for example, a blade drive ring that opens and closes the shutter blades, a drive spring that urges the blade drive ring in the shutter fully closed direction, a charge motor that is rotationally driven by energization, A charge ring that drives the blade drive ring in the fully open direction of the shutter by a rotational force, a charge ring return spring having a biasing force for moving the charge ring back in the fully closed direction, and the blade drive ring in the fully open position of the shutter. The charge release means includes a plunger means for releasing the drive in the shutter fully closed direction by releasing the lock of the blade drive ring by the lock means.

  Further, the charging means includes, for example, a cam gear that is rotationally driven by a charge motor and has a cam in part, a driven piece that is provided on the charge ring and engages with the cam to drive the charge ring itself in the shutter full opening direction, and a blade A locking shaft provided on the drive ring and abutting against the driven piece to drive the blade driving ring in the fully open direction of the shutter, and a locking shaft when the locking shaft is locked at the fully open position of the shutter and driven by the plunger means. And a locking claw plate for releasing the locking.

  In addition, the shutter driving unit includes, for example, at least one position detecting unit that detects the driving position of the charge ring, and a control unit that controls the driving stop position of the charging unit based on the detection output of the position detecting unit. This control means controls a stop position during charging of the charge ring. For example, the control unit is configured to perform control to stop the rotation of the charge motor after a predetermined time has elapsed since the position detection unit detected the predetermined position of the charge ring.

The camera system of the present invention includes the mount adapter of the present invention described above, and when the mount adapter is mounted on the camera body, the shutter mechanism is one of the internal openings of the mount adapter when the camera body main switch is turned off. It is the structure which can be hold | maintained in the state which opened the part. In addition, when the mount adapter of the present invention is attached to the camera body, the shutter mechanism is driven from the fully open state to the fully closed state when the shutter button of the camera body is operated, and the shutter mechanism is The configuration is such that a part of the internal opening is driven open.

According to the present invention, when the mount adapter is mounted on the camera body, a part of the light that has passed through the interchangeable lens is shielded by keeping the internal opening of the mount adapter partially opened by the shutter mechanism. However, since the subject can be displayed on the camera body by the transmitted light, there is no hindrance to normal shooting. On the other hand, when the mount adapter is removed from the camera body, an opening by the shutter mechanism Ri by the be left partially open state, the shutter blade as compared to the fully closed state is reduced, the area which is exposed within the interior opening, the overlapping area of the member for holding the shutter blades Because it becomes larger, even when external force or wind pressure is applied to the shutter blades, the deformation and normal position of the shutter blades Variation from less damage shutter blade is reduced, the normal operation of the shutter is secured.
Yes.

Further, according to the camera system of the present invention, it is possible to set the sheet Yatta mechanism mount adapter half-open state by the operation of the camera body, also holds the inner opening to the half-open state when removing the mount adapter from the camera body It is possible to prevent damage to the shutter blades.

1 is an external perspective view of a camera system provided with a mount adapter of the present invention. The block block diagram of the camera system of FIG. The perspective view which looked at the mount adapter of FIG. 1 from each of the back side and the front side. FIG. 4 is a partially exploded perspective view of FIG. FIG. 4 is a partially exploded perspective view of FIG. Sectional view in the direction perpendicular to the optical axis of the shutter mechanism (shutter fully closed) Sectional view in the direction perpendicular to the optical axis of the shutter mechanism (shutter half-open) Sectional view in the direction perpendicular to the optical axis of the shutter mechanism (shutter fully open) FIG. 6 is a schematic perspective view for explaining the operation of the main part of the shutter mechanism. Timing chart of shutter fully open (during charging). Timing diagram of shutter fully closed (when shuttered) The shutter half-open timing diagram. Sectional drawing of the direction orthogonal to the optical axis explaining the overlapping state of a shutter blade | wing. Sectional drawing of the direction orthogonal to the optical axis of the manual mechanism for half-opening a shutter.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of the camera system of the present invention, and FIG. 2 is a block diagram thereof. This camera system includes a camera body 2 capable of exchanging lenses, a mount adapter 1 attached to a lens mount of the camera body 2, and an interchangeable lens 3 attached to the mount adapter 1. . The camera body 2 is configured as a mirrorless type camera, and includes a control circuit unit 20 including an imaging device 21 and a CPU. Further, a power button (main switch) 22, a shutter button 23, and other operation units are disposed on the outer surface of the camera body 2, and a monitor display device 24 is disposed on the back side of the outer surface. Further, a bayonet type lens mount having a small diameter size, here, an LQ mount 25 which is an LQ type lens mount is disposed on the front surface of the camera body. The LQ mount 25 is provided with a plurality of electrical contact portions 26 that are electrically connected to the mount adapter 1. On the other hand, the interchangeable lens 3 is a lens having an LK mount 35 which is a bayonet type LK lens mount having a larger diameter than the LQ mount 25 of the camera body 2, and includes a lens group 31 constituting an imaging optical system, A diaphragm mechanism 33 that drives and controls the diaphragm 32 and a focus mechanism 34 that drives and controls the lens group 31 are provided. Since the configuration of the camera body 2 and the interchangeable lens 3 has little relation to the present invention, detailed description thereof will be omitted.

  The mount adapter 1 includes an LQ mount portion 13 attached to the LQ mount 25 of the camera body 2 and an LK mount portion 14 to which the LK mount 35 of the interchangeable lens 3 is attached. Thus, the interchangeable lens 3 can be attached to and detached from the camera body 2. The mount adapter 1 includes a shutter mechanism 11, which will be described later in detail, capable of opening and closing the internal opening of the mount adapter, and a shutter circuit unit 12 as a control means for controlling the shutter mechanism 11. Yes.

  FIG. 3 is an external perspective view of the mount adapter. FIG. 3A is a view seen from the side of the LQ mount portion 13 attached to the camera body, and FIG. 3B is a view seen from the opposite LK mount portion 14 side. FIG. The mount adapter 1 includes a cylindrical body 10 having a short cylindrical shape. The LQ mount portion 13 is provided at an end of the cylindrical body 10 on the rear side (camera body side, hereinafter the same), and the front side (interchangeable lens). The LK mount 14 is provided at the end of the side, the same shall apply hereinafter. The LQ mount portion 13 is provided with a plurality of electrical pad portions 15 that are electrically connected to the electrical contact portions 26 of the camera body 2. Further, on the outer periphery of the cylindrical body 10, an operation unit 16 and an operation button 17 each including a knurling ring used when operating the diaphragm 32 of the interchangeable lens 3 are disposed. Further, as shown in FIG. 3B, a shutter mechanism 11 is housed inside the cylinder body 10, and an internal opening 10 a directed in the cylinder axis direction of the cylinder body 10 is formed by the shutter mechanism 11. It can be opened or closed.

  4A and 4B are partially exploded perspective views of the shutter mechanism 11. FIG. 4A is a view as seen from the rear end, that is, the LQ mount portion, as in FIG. 3A, and FIG. It is the figure seen from the front end part, ie, the LK mount part side similarly to b). 4A and 4B, the shutter mechanism 11 includes a shutter blade portion 4 that opens and closes the internal opening 10a of the cylindrical body 10 and a shutter drive portion 5 that drives the shutter blade portion 4 to open and close. Then, the shutter blade of the shutter blade portion 4 is driven to open and close by the control of the shutter circuit portion 12 as a control means provided in the shutter drive portion 5, and the light beam passing through the internal opening 10a of the mount adapter 1 is passed. -It functions as a shutter that blocks light.

  The shutter mechanism 11 will be described in detail mainly with reference to FIG. 4B and FIG. 5A which is a cross-sectional view perpendicular to the cylinder axis. The shutter drive unit 5 is integrated with the cylinder 10 of the mount adapter 1. A fixed main plate 6 is provided, and the main plate 6 is mainly constructed. The parent plate 6 is configured as an annular plate member having an opening 6a connected to the internal opening 10a at the center, and is fixed to the inner peripheral surface of the cylindrical body 10 at the periphery. An annular charge ring 61 is fitted to the main plate 6 along the inner edge of the opening 6 a so that the main plate 6 can rotate about the axis. The charge ring 61 is integrally formed with a fan-shaped follower piece 61a protruding in the outer peripheral direction at a part of the circumference, and a charge ring return spring 62 made of a coil spring is hooked between the charge ring 61 and the parent plate 6. The charge ring 61 is given a habit of rotating counterclockwise in FIG. 4B by the urging force of the charge ring return spring 62.

  In addition, a charge motor 63 is supported on a part of the circumference of the front surface of the master plate 6. When the charge motor 63 is driven, it rotates a worm 63a attached to a rotary output shaft, and the worm The cam gear 65 is decelerated and rotated counterclockwise in FIG. 4B via the relay gear 64 that meshes with 63a. A cam 65a protrudes rearward from a part of the rear surface of the cam gear 65, and the cam 65a becomes an edge of the follower piece 61a of the charge ring 61 on the counterclockwise side as the cam gear 65 rotates. It comes to contact | abut. Further, a locking claw plate 66 and a solenoid plunger 67 are respectively supported on a part of the other circumference of the front surface of the parent plate 6. The locking claw plate 66 has a hook portion 66a at the tip, and is supported so as to be rotatable at a small angle around a support shaft 66b erected on the front surface of the parent plate 6. The locking claw plate 66 is urged counterclockwise in FIG. 4B by a torsion spring 66 c and the base end is connected to the solenoid plunger 67. When the solenoid plunger 67 is not energized, the plunger 67a is buried, and the locking claw plate 66 is rotated clockwise in FIG. 4B against the biasing force of the torsion spring 66c. keeping. When the solenoid plunger 67 is energized, the plunger 67a is protruded, and the locking claw plate 66 is rotated counterclockwise in FIG. 4B based on the urging force of the torsion spring 66c.

  Furthermore, first and second detection switches 68 and 69 are disposed at two different locations in the circumferential direction of the parent plate 61, respectively. The first detection switch 68 disposed at the right position in FIG. 5A is configured as a composite switch having two switches that are turned on and off when the filler 68a tilts to the left and right, that is, the a switch and the b switch. Is engaged with a pair of detection protrusions 61b provided on a part of the circumference of the charge ring 61, and the a switch and the b switch are independently turned ON and OFF according to the rotational position of the detection protrusion 61b. It has become. The second detection switch 69 disposed at the upper position in FIG. 5A is configured as a single switch that is engaged with a locking shaft 71 provided on the blade drive ring 7 to be described later and is switched. As the ring 7 rotates, it is turned ON / OFF. The shutter circuit unit 12 is connected to the charge motor 63, the solenoid plunger 67, the first and second detection switches 68 and 69, and is electrically connected to the electric pad unit 15 of the LQ mount unit 13 to be predetermined. The various electronic components constituting the circuit are constructed on a generally fan-shaped circuit board 12a, and the circuit board 12a is supported by a part of the master plate 6. Yes.

  An annular plate-like blade drive ring 7 is disposed coaxially with the parent plate 6 on the rear surface side of the parent plate 6 and is supported so as to be rotatable about the cylinder axis with respect to the parent plate 6. Yes. A blade drive ring spring 72 comprising a coil spring is mounted between the blade drive ring 7 and the master plate 6, and the blade drive ring 7 is rotated counterclockwise in FIG. 4B by the urging force of the blade drive ring spring 72. The habit of moving is given. A thin columnar locking shaft 71 is erected in the cylinder axis direction at a part of the circumference of the front surface of the blade drive ring 7, and this locking shaft 71 penetrates the parent plate 6 in the cylinder axis direction. The base plate 6 is advanced to the front surface side, and is arranged so as to contact the edge of the follower piece 61a provided on the charge ring 61 on the clockwise side.

  In the shutter drive unit 5 described above, the charge ring 61, the charge motor 63, the cam gear 65, and the blade drive ring 7 constitute charge means in the present invention. Further, the latching claw plate 66, the solenoid plunger 67, and the blade drive ring 7 constitute a charge release means in the present invention.

  The shutter blade portion 4 is disposed on the rear surface side of the blade drive ring 7 and is fixed inside the cylinder body 10. The shutter blade part 4 has a circular base 8 having a circular opening 8a in the center and formed in a circular plate shape, and an annular plate shape having an opening 9a disposed opposite to the rear surface side of the blade base 8. The blade base 8 and the blade retainer 9 are integrated with a minute gap in the cylinder axis direction therebetween. A short cylindrical sleeve 81 is provided in the opening 8 a of the blade base 8, and the sleeve 81 is connected to the parent plate 6. Further, the above-described LQ mount portion 13 is integrally provided on the rear surface of the blade retainer 9. A plurality of shutter blades 91 are housed in a minute gap between the blade base 8 and the blade retainer 9. Here, the plurality of shutter blades 91 are constituted by six thin blade plates, and a small hole 91a formed in a part of each shutter blade 91 is inserted into the support pin 83 of the blade base 8, and each shutter blade 91 is provided. A drive pin 93 erected on 91 is inserted through an arc hole 82 formed in the blade base 8 and engaged with the blade drive ring 7. With this configuration, the six shutter blades 91 are rotated about the support pin 92 by rotating the blade drive ring 7 about the cylinder axis and moving the drive pin 93 in the circumferential direction. The position of each shutter blade with respect to the opening 10a is changed. Thereby, when the blade drive ring 7 is rotated counterclockwise in FIG. 4B, each shutter blade 91 advances into the internal opening 10a and closes the internal opening 10a. When the blade drive ring 7 is rotated in the clockwise direction in FIG. 4B, each shutter blade 91 moves backward from the internal opening 10a to open the internal opening 10a.

  As shown in FIGS. 1 and 2, the mount adapter 1 having the above configuration has the interchangeable lens 3 having the LK mount 35 attached to the LK mount 14, and the mount adapter 1 has the LQ mount 13 attached to the camera body 2. Attached to the LQ mount 25. In particular, when the mount adapter 1 is attached to the camera body 2, the electrical pad portion 15 of the LQ mount portion 13 is electrically connected to the electrical contact portion 26 of the camera body 2, and the mount adapter is connected via the electrical pad portion 15. 1 is electrically connected to the control circuit 20 in the camera body 2, and the charge motor 63, solenoid plunger 67, and first and second detection switches 68 and 69 are connected to the control circuit 20. The shutter mechanism 11 of the mount adapter 1 is electrically connected, and the shutter opening / closing drive is controlled by an operation on the camera body 2 side.

  This shutter operation will be described. As shown in FIG. 5A, in the initial state where the shutter charge is performed, the charge motor 63 is in a predetermined initial rotation position, whereby the cam 65a of the cam gear 65 is located on the counterclockwise side of the driven piece 61a of the charge ring 61. In the edge position. Therefore, the charge ring 61 is in a position rotated counterclockwise by the biasing force of the charge ring return spring 62, and the blade drive ring 7 is also in a position rotated counterclockwise by the biasing force of the blade drive ring spring 72. . Accordingly, each shutter blade 91 of the shutter blade portion 4 is moved into the internal opening 10a corresponding to the initial position of the blade drive ring 72, closes the internal opening 10a, and is in a fully closed state of the shutter.

  When the charge motor 63 is energized and driven, the cam gear 65 is rotated counterclockwise as shown in the schematic diagram of FIG. 6A, so that the cam 65a rotates counterclockwise from the initial position indicated by the chain line. Since it moves and abuts against the counterclockwise edge of the driven piece 61a and further presses the edge of the driven piece 61a, the charge ring 61 resists the biasing force of the charge ring return spring 62 by the driven piece 61a. It is rotated clockwise. As the charge ring 61 rotates, the locking shaft 71 of the blade drive ring 7 that is in contact with the edge of the driven piece 61a in the clockwise direction is rotated together with the driven piece 61a, that is, together with the charge ring 61, in the clockwise direction. Is rotated. As the blade drive ring 7 rotates, the shutter blade 91 gradually opens the internal opening 10a. On the way, the shutter is half-opened as shown in FIG. 5B.

Then, as shown in FIG. 5C, when the locking shaft 71 is rotated clockwise to the maximum position, the shutter blades fully open the internal opening, and at the same time, the locking shaft 71 as shown in FIG. 6B. Is locked to the hook portion 66 a of the locking claw plate 66. At this time, the locking shaft 71 gets over the hook portion 66a by being twisted counterclockwise by the spring force of the spring 66c by twisting the locking claw plate 66 and becomes locked. When the cam gear 65 is further rotated so that the cam 65a is disengaged from the contact with the counterclockwise edge of the driven piece 61a as indicated by a chain line, the charge ring 61 is broken by the urging force of the charge ring return spring 62. It is rotated counterclockwise as indicated by the arrow and returned to the initial position. However, the vane drive ring 7 is held at the locking position because the locking shaft 71 is locked in the counterclockwise direction by the locking at the hook 66a of the locking claw plate 66. That is, the fully opened state of the internal opening 10a by the shutter blade 91 is maintained. This completes charging.

  When the timing at this time is shown in FIG. 7A, the second detection switch 69 is OFF, and the first detection switch 68 has the a switch ON. For example, when the main switch 22 of the camera body 2 is turned on, the charge motor 63 starts to be driven, and when the charge ring 61 starts to rotate clockwise, the a switch of the first detection switch 68 is turned off. When the charge ring 61 is further rotated, the b switch of the first detection switch 68 is turned on. Then, the rotation of the charge motor 63 causes the locking shaft 71 to be locked to the locking claw plate 66 as described above, and the shutter is fully opened. This state is detected when the second detection switch 69 is turned on. Since the rotation of the charge ring 61 is further continued, the b switch of the first detection switch 68 is turned off again. In response to the OFF of the b switch, power supply to the charge motor 63 is stopped, and the charge motor 63 is stopped at the initial position. In addition, as described above, the charge ring 61 is returned to the initial position, and at that time, the a switch and the b switch of the first detection switch 68 are operated in reverse to the above. Is omitted.

  When the solenoid plunger 67 is energized in this state, as shown in FIG. 5A, the plunger 67a protrudes and the latching claw plate 66 rotates counterclockwise by a small angle by the spring force of the torsion spring 66c. Is done. Accordingly, the locking of the locking shaft 71 by the hook portion 66a is released, and the blade driving ring 7 is rotated counterclockwise by the spring force of the blade driving ring spring 72 and returned to the initial position. As a result, the shutter blade 91 fully closes the internal opening 10a. At this time, as shown in FIG. 7B, when the shutter button 23 of the camera body 2 is pressed, the solenoid plunger 67 is energized, and as described above, the locking of the locking shaft 71 is released and the blade driving ring is released. When 7 is rotated counterclockwise, the second detection switch 69 is turned off. Since the charge ring 61 is returned to the initial position, the a switch and the b switch of the first detection switch 68 are not operated, and are in the initial state ON state and the OFF state, respectively.

  The above shutter operation is completed when the power switch (main switch) 22 of the camera body 2 is first turned on when the mount adapter 1 is attached to the camera body 2 or at the time of the previous shooting. When this occurs, the charging operation described above is performed. That is, the shutter blades are fully open, and the subject image formed by the interchangeable lens 3 is transmitted through the internal opening 10a of the mount adapter 1 and captured by the imaging device 21 in the camera body 2. When the release button 23 of the camera body 2 is operated, imaging is started by the imaging device 21, and when a predetermined time has elapsed, a signal is sent to the shutter mechanism 11 of the mount adapter 1 to operate the solenoid plunger 67. Fully close the shutter. This completes photographing with appropriate exposure.

  By the way, when the shutter is fully opened in such an initial state where shooting is not performed as described above, as described above, the external light that is incident on the camera body 2 through the interchangeable lens 3 is a large amount of light in the camera body 2. There is a possibility that the light is condensed on the imaging device 21 and its vicinity, and burnout such as burning or scorching is caused on the imaging device 21 or its vicinity. Further, when the mount adapter 1 is detached from the camera body 2, no electric signal for operation is input to the shutter mechanism 11, and the charge motor 63 is in the initial position and the shutter is fully closed. Therefore, as described above, when the shutter blade 91 is in the fully closed state and comes into contact with the shutter blade 91 exposed from the internal opening 10a of the mount adapter 1 or when stress is applied to the shutter blade 91 by wind pressure or the like, the shutter is caused by this stress. The blade 91 may be deformed, or the shutter blade 91 may be moved from the normal position, and the subsequent normal operation of the shutter may be hindered.

  In the present invention, the shutter can be partially opened, that is, half-opened, when the mount adapter 1 is attached to the camera body 2 and when the mount adapter 1 is detached from the camera body 2. Here, when the main switch 22 is turned off with the mount adapter 1 mounted on the camera body 2, the camera body 1 sends a signal to the charge motor 63 of the shutter mechanism 11 for a predetermined time. The charge motor 63 is rotationally driven for the predetermined time. At this time, the rotation amount of the cam gear 65 is a rotation amount at which the charge ring 61 is not fully charged. In other words, the amount of rotation is such that the cam 65 a presses and moves the driven piece 61 a of the charge ring 61, but the locking shaft 71 is not locked to the hook portion 66 a of the locking claw plate 66. Thereby, in the shutter mechanism 11, the shutter blade 91 is partially opened by partially opening only a part of the entire area of the internal opening 10a.

  As shown in FIG. 7C, when the mount adapter 1 is attached to the camera body 2 and the main switch 22 of the camera body 2 is turned off, the solenoid plunger 67 is forcibly energized. Is done. Thereby, the locking of the locking shaft 71 by the locking claw plate 66 is released, the blade drive ring 7 is returned to the initial position, and the shutter is fully closed. Next, energization of the charge motor 63 is forcibly started, and the charge ring 61 starts to rotate clockwise. That is, as described with reference to FIGS. 5A and 6, the operation of opening the shutter blades is started. When the a switch of the first detection switch 68 is turned off by the rotation of the charge ring 61, the time is measured from this point, and the energization to the charge motor 63 is stopped when a predetermined time has passed. Therefore, the rotation is stopped at a time before the charge ring 61 completes charging, that is, before the locking shaft 71 is locked by the locking claw plate 66 and the shutter is fully opened, and the shutter blade 91 is half opened. It will be stopped in the state of. This state is maintained by the balance between the contact between the cam 65a of the cam gear 65 and the driven piece 61a and the spring force of the charge ring return spring 62, so that it is maintained even when the energization of the charge motor 63 is stopped. become.

  In this way, when the shutter is half open and a part of the internal opening 10a is narrowed, a part of the light transmitted through the interchangeable lens 3 is blocked, but the transmitted light is received by the imaging device 21. The subject can be visually recognized on the monitor 24, and there is little trouble in normal shooting in the camera body 2. On the other hand, even if the light that has passed through the interchangeable lens 3 is condensed on the imaging device 21 in the camera body 2 or in the vicinity thereof, the amount of transmitted light is suppressed as compared with the case where the internal opening 10a is fully opened. Therefore, burn-in and scorch due to the light collection can be suppressed, and burning of the imaging device 21 and the like can be prevented. In addition, since the shutter blade 91 has a larger overlap area with the blade base 8 and the blade retainer 9 when the shutter is half open than when the shutter is fully closed, external force is applied when the mount adapter 1 is removed from the camera body 2. Even when a wind pressure is applied to the shutter blade 91, the shutter blade 91 is not deformed or changed from the normal position, and the shutter blade 91 is less damaged. That is, when the shutter is fully closed, the area where the shutter blade 91 overlaps the blade base 8 and the blade retainer 9 in the cylinder axis direction is small as shown by the diagonal lines in FIG. The tip of the shutter blade 91 may be deformed so as to protrude outside the blade base 8 or the blade retainer 9, but when the shutter is half open, the overlapping area as shown by the diagonal lines in FIG. Therefore, the tip of the shutter blade 91 is prevented from protruding outside the blade base 8 or the blade retainer 9 due to external force or wind pressure, preventing the shutter blade 91 from being damaged and ensuring the normal operation of the shutter. Is done.

  Here, when determining the opening size when the shutter is in the half-open state, the characteristics of the illuminance and the shutter blade overlap when the shutter is fully opened from fully closed are measured. Illuminance is the brightness of the light that passes through the mount adapter 1 and enters the camera body 2, and the shutter blade overlap is the area of the area shown by the oblique lines in FIG. The former is a characteristic that is approximately proportional to the square of the opening dimension of the shutter opening, and the latter is a characteristic that is also approximately proportional to the opening dimension. From these characteristics, it is considered preferable that the shutter is open approximately half (1/2) of the fully open state. Thus, by setting the aperture size to be half open, the above-described burnout prevention effect can be obtained. It is possible to obtain both the damage prevention effect.

  In the above-described embodiment, the shutter is half open by controlling the energization of the charge motor 63. However, the shutter may be set half open by a manual operation. FIG. 9A is a cross-sectional view orthogonal to the optical axis showing an example thereof. The blade base of the above embodiment is composed of two members, a fixed base 8A and a movable base 8B, and the movable base 8B is used as the fixed base 8A. On the other hand, it is configured to be rotatable relative to the optical axis within a minute angle range. In addition, guide pins 95 are erected at a plurality of circumferential positions of the blade retainer 9, and the movable base 8B can be rotated by engaging notches 85 provided on the inner edge of the movable base 8B with the guide pins 95. I have to. An operation portion 86 protruding from the outer peripheral surface of the mount adapter 1 is provided at two locations on the outer periphery of the movable base 8A. The operation portion 86 can be rotated to an arbitrary angular position by manually operating the operation portion 86. ing. Further, the movable base 8B is engaged with the drive pin 93 of the shutter blade 91, and the plurality of shutter blades 91 can be opened and closed by the rotation of the movable base 8B.

  According to this configuration, as shown in FIG. 9B, the movable base 8B is appropriately manually operated as shown in FIG. 9B regardless of whether the mount adapter 1 is attached to the camera body 2 or removed from the camera body 2. , The shutter blade 91 can be arbitrarily opened and closed, and the shutter can be set to a desired open state. Therefore, by setting the shutter half open, it is possible to prevent burning of the imaging device or the like when mounted on the camera body 2 as described above, and it is possible to prevent damage to the shutter blades 91 when removed from the camera body 2. . Also, with this configuration, the shutter can be set to an arbitrary aperture diameter by operating the movable base 8B, so that the minimum necessary shutter aperture state when using an interchangeable lens with a narrow luminous flux can be configured. The moving distance of the shutter blades until fully closed can be reduced, and a high-speed shutter can be realized. In addition, the shutter can be used as a manual diaphragm, for example, for pinhole photography.

  Therefore, when the mount adapter 1 of the present invention is used, a camera system is constructed by mounting the interchangeable lens 3 of the LK mount on the camera body 2 of the LQ mount, and then shooting is performed using the interchangeable lens 3 and the camera body 2. Of course, even in the case of a camera body that can only shoot with a so-called electronic shutter when shooting with the imaging device 21, shooting using the shutter mechanism 11 provided in the mount adapter 1 becomes possible. It is possible to prevent problems such as distortion of the photographed subject image. Also, when the interchangeable lens 3 is not attached, the mount adapter 1 is attached to the camera body 2, and the main switch 22 is turned off to set the shutter mechanism 11 in a half-open state. Can be prevented. Furthermore, even when the mount adapter 1 is subsequently removed from the camera body 2, the shutter mechanism 11 can be kept in the half-open state, so that the shutter blade portion can be prevented from being damaged. Thereby, an accident in the mount adapter 1 or the camera body 2 can be prevented, and a highly reliable camera system can be constructed.

  Further, the camera system of the present invention may be configured such that the shutter can be controlled when the camera body is turned on, and the shutter may be controlled to be half open when a through image is displayed, for example, other than taking a still image. . Furthermore, the camera system of the present invention may be configured so that the interchangeable lens and the camera body can be electrically communicated with each other via a mount adapter, and the shutter may be controlled to be half open by detecting the attachment / detachment of the interchangeable lens.

  The present invention can be used in an interchangeable lens digital camera equipped with an imaging device, and is particularly employed in a mount adapter and a camera system for taking a picture using an interchangeable lens having a lens mount different from a lens mount provided in a camera body. It is valid.

DESCRIPTION OF SYMBOLS 1 Mount adapter 2 Camera body 3 Interchangeable lens 4 Shutter blade part 5 Shutter drive part 6 Master plate 7 Blade drive ring 8 Blade base 9 Blade presser 10 Cylindrical body 10a Internal opening 11 Shutter mechanism 61 Charge ring 63 Charge motor 65 Cam gear 66 Locking Claw plate 67 Solenoid plunger 68 First detection switch 69 Second detection switch 71 Locking shaft 91 Shutter blade

Claims (10)

A mount adapter comprising a first lens mount portion that can be attached to a first type lens mount provided on a camera body, and a second lens mount portion that can be attached to an interchangeable lens having a second type lens mount. there, with a closing operable shutter mechanism inside the opening of the mount adapter, the shutter mechanism is held in the mounting adapter has opened part of the inner opening when removed from the camera body It is possible to mount adapter. The shutter mechanism includes a shutter blade portion for opening and closing the internal opening and a shutter drive portion for driving the shutter blade portion, and the shutter drive portion opens the shutter blade portion from a fully closed state to a fully open state. 2. The mount adapter according to claim 1, wherein the mount adapter is configured to be driven to an arbitrary opening state between the two, and to maintain the opening state.   The shutter drive unit includes a charge unit that drives the shutter blade unit from a fully closed state to a fully open state, and a charge release unit that releases the charge state of the charge unit and returns the shutter blade unit to a fully closed state. The mounting adapter according to claim 2, wherein the charging means is configured to be able to stop the charging operation during charging.   The charging means includes a blade driving ring that opens and closes the shutter blade, a driving spring that urges the blade driving ring in the shutter fully closing direction, a charge motor that is rotationally driven by energization, and a rotational force of the charge motor A charge ring for driving the blade drive ring in the fully open direction of the shutter, a charge ring return spring having a biasing force for moving the charge ring back in the fully closed direction, and locking the blade drive ring in the fully open position of the shutter. The charge release means includes a plunger means for releasing the drive in the shutter fully closed direction by releasing the lock of the blade drive ring by the lock means. Item 4. The mount adapter according to item 3.   The charging means includes a cam gear that is rotationally driven by the charge motor and has a cam in a part thereof, a driven piece that is provided on the charge ring and engages with the cam to drive the charge ring itself in the fully open direction of the shutter, A locking shaft provided on a blade driving ring and contacting the driven piece to drive the blade driving ring in the fully open direction of the shutter; and when the locking shaft is locked in the fully open position and driven by the plunger means The mount adapter according to claim 4, further comprising a locking claw plate that releases locking of the locking shaft.   The shutter drive unit includes at least one position detection unit that detects a drive position of the charge ring, and a control unit that controls a drive stop position of the charge unit based on a detection output of the position detection unit. The mount adapter according to claim 4 or 5.   The mount adapter according to claim 6, wherein the control unit controls a stop position in the middle of charging of the charge ring.   8. The mount according to claim 7, wherein the control unit performs control to stop the rotation of the charge motor after a predetermined time has elapsed since the predetermined position of the charge ring was detected by the position detection unit. adapter. The mount adapter according to any one of claims 1 to 8 , wherein the shutter mechanism is attached to the camera body when the main switch of the camera body is turned off with the mount adapter attached to the camera body . camera system characterized in that it is possible to hold a part of the internal opening in the state of being opened. 9. The mount adapter according to claim 1, wherein the mount adapter is attached to the camera body, and the shutter mechanism is opened inside the mount adapter when the shutter button of the camera body is operated. Is driven from the fully open state to the fully closed state , and when the main switch of the camera body is turned off, the shutter mechanism is driven to a state in which a part of the internal opening of the mount adapter is opened.

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