JP5825901B2 - Adapter and camera system - Google Patents

Description

  The present invention relates to an adapter and a camera system.

  The camera system has a camera body and an interchangeable lens. The camera body has a pin that regulates the relative position of the interchangeable lens with respect to the camera body in the circumferential direction around the optical axis of the interchangeable lens. The camera system adjusts the exposure amount and the depth of field by changing the aperture of the interchangeable lens to capture an image (see, for example, Patent Document 1 and Patent Document 2).

  The interchangeable lens has a diaphragm drive member that changes the aperture ratio of the diaphragm of the interchangeable lens. The aperture ratio of the diaphragm of the interchangeable lens changes due to the displacement of the diaphragm driving member. For example, the camera body rotates an annular movable member connected to the aperture driving member, a support member that supports the movable member in a circumferential direction around the optical axis of the interchangeable lens, and the movable member. And a driving device. The movable member is disposed so as to surround the optical axis of the interchangeable lens with the interchangeable lens attached to the camera body, and is connected to the aperture driving member. The driving device rotates the movable member connected to the diaphragm driving member in the rotation direction defined by the support member. Thus, the camera body changes the aperture ratio of the diaphragm by displacing the diaphragm driving member.

Japanese Patent Laid-Open No. 4-116663 Japanese Patent Laid-Open No. 4-121720

By the way, the interchangeable lens may be attached to the camera body via an adapter. At this time, the movable member, the support member, and the driving device provided in the camera body may be provided in the adapter.
The drive device is generally controlled by a control unit that controls the drive device, and transmits the torque generated by the electric motor or the like to the movable member via the reduction gear train to rotate the movable member.
When controlling the aperture of the interchangeable lens, first, after moving the movable member by controlling the driving device so that the aperture drive member of the interchangeable lens is positioned at the open aperture, the aperture drive member is positioned at the open aperture, The drive device may be controlled to move the movable member until the aperture driving member reaches a position corresponding to a desired aperture value.

Therefore, in order to accurately control the aperture of the interchangeable lens, it is very important to accurately grasp the position of the movable member when the aperture driving member is located at the open aperture position. On the other hand, the full aperture position of the interchangeable lens diaphragm drive member varies depending on the specifications of the interchangeable lens.
Therefore, there is a need for a technique that can accurately detect the position of the movable member when the aperture driving member of the interchangeable lens is positioned at the open aperture position even when the interchangeable lens has a different aperture position. ing.

  The present invention has been made in view of the above circumstances, and provides an adapter and a camera system that can accurately detect the position of the movable member when the aperture driving member is located at the open aperture position. For the purpose.

    An adapter according to a first aspect of the present invention is an adapter that connects an interchangeable lens having a diaphragm driving member and a camera body, and is movable within a predetermined range in contact with at least a part of the diaphragm driving member. A movable member; a drive unit connected to the movable member via a gear train including a plurality of gears; and a power transmission path from the drive unit to the movable member in the gear train. An excessive power transmission preventing unit for preventing excessive power from being transmitted from the drive unit side to the motor, and a detecting unit for detecting a movable or stopped state of the movable member.

  A camera system according to a second aspect of the present invention includes the adapter according to the first aspect, a camera body connected to the adapter, and an aperture drive member, and the aperture drive member contacts a movable member of the adapter. And an interchangeable lens.

  ADVANTAGE OF THE INVENTION According to this invention, even if it replaces | exchanges an interchangeable lens, the adapter and camera system which can grasp | ascertain the open aperture position of an interchangeable lens correctly can be provided.

It is a perspective view which shows the camera system of this embodiment. It is a figure which shows the function structure of the camera system of this embodiment. It is a perspective view which shows the adapter of this embodiment. It is a top view which shows the adapter of this embodiment. It is a top view which shows the 2nd mount of this embodiment, a movable member, and a drive device. It is a perspective view which shows the movable member and drive device of this embodiment. It is a perspective view which shows the drive device of this embodiment. It is a top view which shows the movable member and drive device of this embodiment. It is sectional drawing which shows the support roller and movable member of this embodiment. It is a top view which shows the movable member, drive device, and pressing plate of this embodiment. It is a top view which shows the modification of the adapter of this embodiment. It is a mechanism figure showing typically the drive system of the movable member of this embodiment. It is a disassembled perspective view of the friction connection part of this embodiment. It is a top view which shows when the movable member of this embodiment is located in the maximum opening position and the minimum opening position.

This embodiment will be described. FIG. 1 is a perspective view showing the camera system of the present embodiment.
A camera system 1 shown in FIG. 1 includes a camera body 100, an interchangeable lens 200, and an adapter 300. The adapter 300 is attached to the camera body 100. The interchangeable lens 200 is attached to the adapter 300 on the side opposite to the camera body 100 with respect to the adapter 300.

  The camera body 100 of the present embodiment includes a first mount 11. The first mount 11 can be attached with an interchangeable lens or the like having a mount whose size matches that of the first mount 11. The mount of the interchangeable lens 200 of the present embodiment is different in size from the first mount 11. Therefore, the interchangeable lens 200 cannot be directly attached to the camera body 100. The interchangeable lens 200 can be indirectly attached to the first mount 11 via the adapter 300. That is, the adapter 300 has a mount that matches the size of the first mount 11 so that it can be directly attached to the camera body 100. Furthermore, the adapter 300 has a second mount 362 on the opposite side to which the camera body 100 is attached so that the interchangeable lens 200 can be directly attached.

  The camera body 100 of the present embodiment includes a top surface 13 located at the upper part of the side surface facing the front surface 12 on which the first mount 11 is disposed, and a back surface 14 facing the opposite side to the front surface 12. Have The camera body 100 of the present embodiment can be attached to the top surface 13 with accessories such as a flash device.

  In the present embodiment, the XYZ orthogonal coordinate system shown in FIG. 1 or the like is set, and the positional relationship of each part may be described. In this XYZ orthogonal coordinate system, the Y-axis direction is a direction substantially parallel to the optical axis AX of the interchangeable lens 200. In this XYZ orthogonal coordinate system, the X-axis direction and the Z-axis direction are directions orthogonal to the Y-axis direction and orthogonal to each other. The front surface 12 and the back surface 14 are each substantially orthogonal to the Y-axis direction. The top surface 13 is substantially orthogonal to the Z-axis direction.

  FIG. 2 is a diagram illustrating a functional configuration of the camera system according to the present embodiment. As shown in FIG. 2, in the camera system 1, the light incident on the interchangeable lens 200 enters the image sensor 110 of the camera body 100 through the interchangeable lens 200 and the adapter 300. The camera system 1 can capture an image formed on the image sensor 110 of the camera body 100 by the interchangeable lens 200 with the camera body 100.

  The interchangeable lens 200 according to the present embodiment includes a plurality of lenses 201, a diaphragm unit 202 (aperture diaphragm), a diaphragm driving member 203, a lens control unit 204, a first terminal unit 205, and a lens barrel 206. The plurality of lenses 201 refract the light incident on the interchangeable lens 200 and form an image on the light receiving surface of the image sensor 110 of the camera body 100. The aperture unit 202 changes the amount of light incident on the image sensor 110 through the plurality of lenses 201 according to the aperture ratio. The aperture driving member 203 is, for example, an aperture lever that works in conjunction with the aperture unit 202. The aperture ratio of the aperture unit 202 varies depending on the displacement of the aperture drive member 203. The camera system 1 can control the exposure amount and the depth of field for the image sensor 110 by controlling the aperture ratio of the aperture unit 202. The lens barrel 206 houses and protects a plurality of lenses 201, a diaphragm unit 202, and a lens control unit 204. The first terminal portion 205 is attached to the lens barrel 206. The first terminal unit 205 is connected to the lens control unit 204. The first terminal portion 205 is connected to the second terminal portion 330 of the adapter 300 in a state where the interchangeable lens 200 is attached to the adapter 300 (hereinafter referred to as a wearing state of the interchangeable lens 200). The lens control unit 204 of the present embodiment controls the positions of the plurality of lenses 201 in a direction substantially parallel to the optical axis AX, focusing control for controlling the focal positions of the plurality of lenses 201, and zoom control for controlling the zoom magnification. Etc.

  The adapter 300 according to the present embodiment includes a movable member 310, a driving device 320, a second terminal unit 330, a third terminal unit 340, and an adapter control unit 350. The movable member 310 is driven by the driving device 320 to displace the diaphragm driving member 203 of the interchangeable lens 200. The second terminal unit 330 and the third terminal unit 340 are each connected to the adapter control unit 350. The second terminal portion 330 is connected to the first terminal portion 205 of the interchangeable lens 200 when the interchangeable lens 200 is attached. The third terminal portion 340 is connected to the fourth terminal portion 120 of the camera body 100 in a state where the adapter 300 is attached to the camera body 100 (hereinafter referred to as a wearing state of the adapter 300). The adapter 300 will be described in detail later.

  As shown in FIG. 1, the camera body 100 of the present embodiment includes a release button 15, a first attachment / detachment switch 16, and a housing 17 (warship part). The camera body 100 includes an image sensor 110, a fourth terminal unit 120, and a camera control unit 130, as shown in FIG.

  The release button 15 of the present embodiment is disposed on the top surface 13. The camera body 100 detects that the release button 15 has been operated (half-pressed or fully pressed), and performs various processes such as an imaging process.

  The first attachment / detachment switch 16 of this embodiment is disposed on the front surface 12. The interchangeable lens 200 or the adapter 300 attached to the first mount 11 can be detached from the first mount 11 by operating the first attachment / detachment switch 16. The first attachment / detachment switch 16 is interlocked with a pin disposed on the first mount 11. This pin regulates the relative position between the camera body 100 and the adapter 300 in the circumferential direction around the optical axis AX when the adapter 300 is worn. That is, this pin regulates the relative position so that the adapter 300 does not rotate with respect to the camera body 100 in the circumferential direction around the optical axis AX when the adapter 300 is attached.

  The housing 17 of this embodiment houses and protects the image sensor 110 and the camera control unit 130. The fourth terminal portion 120 is provided on the housing 17. The fourth terminal unit 120 is connected to the third terminal unit 340 of the adapter 300 when the adapter 300 is attached. The camera body 100 of the present embodiment includes a battery that supplies power to each part in the camera body 100.

  The image sensor 110 according to the present embodiment includes a plurality of pixels arranged two-dimensionally. Each pixel of the image sensor 110 includes a light receiving element such as a CCD (Charge Coupled device) or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The light receiving element of the image sensor 110 generates a charge corresponding to the amount of light incident on each pixel from the interchangeable lens 200. The image sensor 110 converts the charge generated in the light receiving element by the light incident on each pixel into a signal. The image sensor 110 generates an image signal indicating an image of a subject formed on the light receiving surface of the image sensor 110 via the interchangeable lens 200.

  The camera control unit 130 of the present embodiment detects an operation indicating that the release button 15 has been operated (half-pressed or fully pressed). The camera control unit 130 controls the image sensor 110 based on the detected operation and executes an imaging process. In addition, the camera control unit 130 causes the interchangeable lens 200 to execute processing required for performing the imaging processing via the adapter 300.

  In the present embodiment, the camera control unit 130 transmits a control signal for controlling the adapter control unit 350 and a signal indicating information required for imaging via the fourth terminal unit 120 and the third terminal unit 340. Output to the controller 350. The adapter control unit 350 outputs a control signal for controlling the lens control unit 204 and a signal indicating information necessary for imaging to the lens control unit 204 via the second terminal unit 330 and the first terminal unit 205. To do. The lens control unit 204 outputs a signal indicating information required for imaging to the adapter control unit 350 via the first terminal unit 205 and the second terminal unit 330. The camera body 100 of this embodiment has a battery that supplies power to each part of the camera system 1. The camera body 100 supplies power to each part in the adapter 300 via the fourth terminal part 120 and the third terminal part 340. Further, the adapter 300 supplies the power supplied from the camera body 100 to each part in the interchangeable lens 200 via the second terminal unit 330 and the first terminal unit 205. The first terminal unit 205, the second terminal unit 330, the third terminal unit 340, and the fourth terminal unit 120 are respectively paired with a signal terminal for inputting / outputting a signal, a power supply terminal for supplying power, and a power supply terminal. And a ground terminal.

  Next, the adapter 300 will be described in detail. FIG. 3 is a perspective view showing the adapter of the present embodiment. FIG. 4 is a plan view showing the adapter of the present embodiment.

  The adapter 300 of this embodiment includes a first housing member 360, a second housing member 361, a second mount 362, a pin 363, and a second attach / detach switch 364.

  The second housing member 361 of the present embodiment houses at least a part of the drive device 320 shown in FIG. The second accommodation member 361 of the present embodiment is generally box-shaped. The second housing member 361 has a surface (hereinafter referred to as a bottom surface 365) that faces in a direction (−Z direction) intersecting the optical axis AX of the interchangeable lens 200 when the interchangeable lens 200 is attached. The bottom surface 365 has a screw hole or the like that can fix the adapter 300 to a tripod or the like. The second housing member 361 is joined to the first housing member 360 on the surface facing the bottom surface 365 (+ Z direction). The bottom portion 366 including the bottom surface 365 protrudes toward the outside of the adapter 300 with respect to the ceiling portion 367 including the surface joined to the first housing member 360. The bottom portion 366 is disposed so as to protrude toward the interchangeable lens 200 from the ceiling portion 367 when the interchangeable lens 200 is attached.

  The first housing member 360 of the present embodiment houses the movable member 310, the second terminal portion 330, the third terminal portion 340, and the adapter control portion 350. The first housing member 360 is supported by the second housing member 361 in a state where the bottom surface 365 of the second housing member 361 is supported by a tripod, a desk, or the like.

  The 1st accommodating member 360 of this embodiment is cylindrical. The axial direction of the first housing member 360 is substantially parallel to the optical axis AX of the interchangeable lens 200 when the interchangeable lens 200 is attached. The first housing member 360 has a first opening 368 and a second opening 369. The first opening 368 is arranged in a direction (−Y direction) facing the camera body 100 when the adapter 300 is worn. The second opening 369 is disposed in a direction (+ Y direction) facing the interchangeable lens 200 when the interchangeable lens 200 is worn. The light incident on the adapter 300 from the interchangeable lens 200 passes through the second opening 369 and then passes through the first opening 368 and enters the camera body 100.

  The second mount 362 of this embodiment is attached to the first housing member 360. The second mount 362 is disposed on the surface facing the opposite side (+ Y direction) from the camera body 100 when the adapter 300 is attached. The second mount 362 of the present embodiment is annular. The second mount 362 has a mount surface 370 that contacts the interchangeable lens 200. The second mount surface 370 is at least partially flat. The second mount 362 is disposed so that the optical axis AX of the interchangeable lens 200 passes through the center of the second mount 362 when the interchangeable lens 200 is attached.

  The second terminal portion 330 of this embodiment is disposed in the vicinity of the inner periphery of the second opening 369. A part of the second terminal portion 330 protrudes to the inside of the inner periphery of the second opening 369. The second terminal portion 330 is arranged so that the second opening 369 is sandwiched between the second terminal portion 330 and the second housing member 361. In the present embodiment, the circumferential position (rotational position) about the optical axis AX may be indicated by an angle with the position of the second terminal portion 330 as a reference (0 °). This angle is positive when viewed from one side in the optical axis direction (as viewed in the −Y direction) and negative when counterclockwise.

  The pin 363 and the second attachment / detachment switch 364 of the present embodiment are disposed at a rotation position of approximately 90 ° from the second terminal portion 330 in the circumferential direction around the optical axis AX. The pin 363 can advance and retreat in the normal direction (Y-axis direction) of the mount surface 370. For example, the pin 363 can move back and forth between a first position protruding from the mount surface 370 and a second position not protruding from the mount surface 370. The pin 363 moves forward and backward when the second attachment / detachment switch 364 is operated.

  The pin 363 of the present embodiment is inserted into a hole (not shown) provided in the interchangeable lens 200 when the pin 363 is disposed at the first position in the attached state of the interchangeable lens 200. The pin 363 restricts the relative position of the interchangeable lens 200 with respect to the adapter 300 in the circumferential direction around the optical axis of the interchangeable lens 200 in a state where the pin 363 is inserted into a hole provided in the interchangeable lens 200. That is, the pin 363 prevents the interchangeable lens 200 from rotating with respect to the adapter 300 in the circumferential direction around the optical axis of the interchangeable lens 200. The pin 363 is not inserted into the hole provided in the interchangeable lens 200 when the pin 363 is disposed at the second position in the wearing state of the interchangeable lens 200. Therefore, the interchangeable lens 200 can be detached from the second mount 362 when the pin 363 is disposed at the second position by the operation of the second attachment / detachment switch 364.

  FIG. 5 is a plan view showing the second mount, the movable member 310, and the driving device 320 of the present embodiment. The movable member 310 and the driving device 320 according to the present embodiment are disposed in a range overlapping the second mount 362 when viewed from the optical axis direction (Y-axis direction). The movable member 310 and the driving device 320 are disposed on the opposite side (−Y direction) from the interchangeable lens 200 with respect to the second mount 362. In FIG. 5, the movable member 310 and the driving device 320 are schematically illustrated through the second mount 362 and the like.

  The movable member 310 of the present embodiment has substantially the same shape (a crescent shape, a circular arc) as a portion occupying a predetermined angular range α [°] in the circumferential direction around the optical axis AX in the ring around the optical axis AX. Shape). In the present embodiment, the angle range α [°] is about 150 °. The angle range α [°] may be, for example, 180 ° or less, 120 ° or less, or 90 ° or less. The movable member 310 is provided to be rotatable by an angle (θ1 + θ2) [°] counterclockwise in the circumferential direction around the optical axis AX from the state shown in FIG.

The driving device 320 according to the present embodiment is provided in a range that spans a region inside the inner circumference of the second mount 362 and a region outside the outer circumference of the second mount 362 when viewed from the optical axis direction (Y-axis direction). It has been. The drive device 320 of this embodiment is disposed at an angular position of approximately −150 °. The driving device 320 rotates the movable member 310 within a predetermined angular range in the circumferential direction around the optical axis AX. A first state where the movable member 310 is rotated to a position where it can be moved most counterclockwise, and a second state where the movable member 310 is rotated to a position where it can be moved most clockwise (maximum opening position described later). Thus, the rotational position of one end of the movable member 310 in the circumferential direction around the optical axis AX changes by an angle (θ1 + θ2) [°]. That is, the first range A1 in which the movable member 310 is rotatable is a section corresponding to the circumferential angular range (α + θ1 + θ2) [°] around the optical axis AX in the ring centered on the optical axis AX. is there.
The second state in which the movable member 310 is rotated to the position where it can move most clockwise is when the diaphragm driving member 203 of the interchangeable lens 200 is located at a position corresponding to the maximum aperture ratio (open diaphragm state). The state of the movable member 310 illustrated in FIG. 5 indicates the second state. The position of the movable member 310 in the second state is referred to as the maximum opening position.
The movable member 310 can rotate an angle (θ1 + θ2) [°] counterclockwise in the circumferential direction around the optical axis AX from the maximum opening position.

  In the present embodiment, the distance L1 between the movable member 310 and the optical axis AX is the distance L2 between the second terminal portion 330 and the optical axis AX with respect to the radial direction centered on the optical axis AX (the radial direction of the second mount 362). Is almost the same. That is, with respect to the radiation direction centered on the optical axis AX, the distance between a part of the movable member 310 and the optical axis AX is the same as the distance between a part of the second terminal portion 330 and the optical axis AX. When the movable member 310 is closest to the second terminal portion 330 (second state), the second terminal portion 330 is a terminal of the second terminal portion 330 when viewed from the optical axis direction (Y-axis direction). It is set not to overlap. In other words, the second terminal portion 330 is arranged in the second range A2 excluding the first range A1 in which the movable member 310 can rotate in the circumferential direction around the optical axis AX.

  In the present embodiment, the distance L1 between the movable member 310 and the optical axis AX is substantially the same as the distance L3 between the pin 363 and the optical axis AX with respect to the radiation direction centered on the optical axis AX. That is, with respect to the radiation direction centered on the optical axis AX, the distance between a part of the movable member 310 and the optical axis AX is the same as the distance between a part of the pin 363 and the optical axis AX. The pin 363 is disposed in the second range A2 excluding the first range A1 in which the movable member 310 can rotate in the circumferential direction around the optical axis AX.

FIG. 6 is a perspective view showing the movable member 310 and the driving device 320 of the present embodiment. FIG. 7 is a perspective view showing the driving device 320 of the present embodiment. FIG. 8 is a plan view showing the movable member 310 and the drive device 320 of the present embodiment. FIG. 9 is a cross-sectional view showing the support roller 387 and the movable member 310 of the present embodiment. FIG. 10 is a plan view showing the movable member 310, the driving device 320, and the presser plate 393 of the present embodiment.
FIG. 11 is a plan view showing a modification of the adapter of the present embodiment.

  As shown in FIG. 6, the movable member 310 of the present embodiment includes a main body portion 371, a first contact portion 372, a first gear portion 373, and a flange portion 374. The movable member 310 rotates by the force (transmitted torque) received by the first gear unit 373 (input unit) from the driving device 320. The movable member 310 according to the present embodiment drives the diaphragm by causing the first contact portion 372 (output unit) to act (transmit) to the diaphragm driving member 203 of the interchangeable lens 200 by the rotation of the movable member 310. The member 203 is displaced.

  In the present embodiment, the outer shape of the main body 371 viewed from the optical axis direction (Y-axis direction) is substantially the same as the outer shape of the movable member 310 viewed from the optical axis direction. The main body 371 has substantially the same shape as a portion that occupies a predetermined angular range α [°] in the circumferential direction around the optical axis AX in the ring around the optical axis AX. As shown in FIG. 9, the main body 371 of this embodiment includes a first surface 375 that faces the + Y direction in the optical axis direction, a second surface 376 that faces the −Y direction, an outer edge of the first surface 375, and a second edge. A third surface 377A and a fourth surface 377B are connected to the outer edge of the surface 376. The movable member 310 of the present embodiment includes a first member 378 including a first surface 375 and a second member 379 including a second surface 376. In the present embodiment, the first member 378 and the second member 379 are each formed by molding a resin material or the like. The main body 371 is not formed of the first member 378 and the second member 379, but may be integrally formed of a resin material.

  The first contact portion 372 of the present embodiment is attached to the first member 375 of the main body 371 on the same side (+ Y side) as the second mount 362 with respect to the main body 371. The first contact portion 372 protrudes to the inside of the inner periphery of the second mount 362 when viewed from the + Y direction in the optical axis direction (as viewed in the −Y direction). The first contact portion 372 contacts the aperture driving member 203 of the interchangeable lens 200 when the interchangeable lens 200 is attached. The diaphragm driving member 203 of the interchangeable lens 200 is biased in a predetermined direction (counterclockwise direction when viewed from the + Y side). When the interchangeable lens 200 is in the worn state, the first contact portion 372 is biased by the biasing force. Pressed against. The first contact portion 372 rotates integrally with the main body portion 371 while being in contact with the aperture driving member 203, thereby moving the aperture driving member 203 in a predetermined direction in which the aperture driving member 203 is biased. Displace.

  The first gear portion 373 of the present embodiment is disposed in the vicinity of the drive device 320. The first gear portion 373 of the present embodiment is arranged in an angular range of −180 ° or more and less than −90 ° with respect to a circumferential position (angular position) about the optical axis AX. The first gear portion 373 of the present embodiment is attached to the fourth surface 377B of the main body portion 371 that faces outward in the radial direction about the optical axis AX. The first gear portion 373 includes a plurality of gear teeth facing outward in the radial direction about the optical axis AX. The center of the pitch circle 380 of the first gear portion 373 substantially coincides with the optical axis AX of the interchangeable lens 200. The plurality of gear teeth of the first gear portion 373 are arranged in a range corresponding to a part of the pitch circle 380 in the circumferential direction.

  The flange portion 374 of the present embodiment is provided in substantially the same angular range as the first gear portion 373 in the circumferential direction centered on the optical axis AX. The flange portion 374 is attached to the second member 376 of the main body 371 on the same side as the second mount 362 (+ Y direction) with respect to the main body 371. The flange portion 374 of the present embodiment protrudes from the tooth portion of the first gear portion 373 toward the outside in the radial direction centering on the optical axis AX from the main body portion 371.

  As shown in FIG. 7, the drive device 320 of this embodiment includes a second gear part (power transmission part) 381, a second contact part 382, an actuator 383, and an encoder 384.

  The second gear unit 381 of this embodiment outputs the power input from the actuator 383 to the first gear unit 373. Second gear portion 381 includes a plurality of gears. In the second gear portion 381, the gear teeth of the first gear 385 among the plurality of gears are meshed with the gear teeth of the first gear portion 373. The first gear 385 is disposed outside the first gear portion 373 in the radial direction with the optical axis AX as the center. The power transmission unit may transmit the power output from the actuator 383 to the first gear unit 373 using friction or the like.

  The 2nd contact part 382 of this embodiment is cyclic | annular. The shaft of the second contact portion 382 is connected so as to be coaxial with the rotation shaft of the first gear 385 of the second gear portion 381. The second contact portion 382 is in contact with the flange portion 374 of the first gear portion 373 to form a gap between the first gear portion 373 and the first gear 385 of the second gear portion 381. That is, the dimensions and positions of the second contact portion 382 and the flange portion 374 in the radial direction about the optical axis AX are the first in a state where the tooth tip of the first gear portion 373 does not reach the tooth base of the first gear 385. The gear portion 373 and the first gear 385 of the second gear portion 381 are set to contact each other.

  The actuator 383 of this embodiment includes an electric motor (stepping motor). The actuator 383 is connected to the second gear portion 381. The actuator 383 supplies torque to the second gear portion 381 and rotates the first gear 385 of the second gear portion 381. The second gear portion 381 will be described in detail later.

  The encoder 384 of this embodiment detects rotation information indicating the rotation state of at least one gear among the plurality of gears of the second gear unit 381. The rotation state of the gear includes at least one of the rotation speed and the rotation position of the gear. The encoder 384 outputs the detected rotation information to the adapter control unit 350.

  As shown in FIGS. 7 and 8, the adapter 300 of this embodiment includes a sensor 386 that detects position information regarding the position of the movable member 310. The sensor 386 optically detects information related to the position of the movable member 310. The sensor 386 can detect whether or not the movable member 310 is rotated most counterclockwise in the circumferential direction around the optical axis AX. The sensor 386 outputs the detected position information to the adapter control unit 350.

  The adapter control unit 350 controls the actuator 383 based on at least one of the rotation information output from the encoder 384 and the position information output from the sensor 386, thereby rotating the first gear 385 of the second gear unit 381. You can control the state. The adapter control unit 350 controls the rotational position of the movable member 310 by controlling the rotational state of the first gear 385, and as a result, can control the displacement of the aperture driving member 203.

  As shown in FIGS. 6 and 7, the adapter 300 according to this embodiment includes a support roller 387 that supports the movable member 310 so that the movable member 310 can smoothly rotate in the circumferential direction around the optical axis AX. Have In the present embodiment, the support roller 387 includes a first support roller 387A, a second support roller 387B, and a third support roller 387C.

  The first support roller 387A is disposed on the inner side with respect to the movable member 310 in the radial direction centered on the optical axis AX. The first support roller 387A is arranged at a position closer to the first contact portion 372 than the second gear portion 381 with respect to the rotational position in the circumferential direction around the optical axis AX. The first support roller 387A is arranged so that the imaginary line connecting the optical axis AX and the center of the first support roller 387A intersects the movable range of the first contact portion 372 when viewed from the optical axis direction (Y-axis direction). It is disposed in the vicinity of the one contact portion 372. The third support roller 387C is disposed on the outer side with respect to the movable member 310 in the radial direction centered on the optical axis AX. The third support roller 387C is disposed so as to sandwich the movable member 310 with the first support roller 387A.

  The second support roller 387B is disposed on the inner side with respect to the movable member 310 in the radial direction centered on the optical axis AX. The second support roller 387B is disposed at a position closer to the first gear portion 373 than the first support roller 387A. The second support roller 387B has a first gear portion such that an imaginary line connecting the optical axis AX and the center of the second support roller 387B intersects the first gear portion 373 when viewed from the optical axis direction (Y-axis direction). It is arranged in the vicinity of 373. The second support roller 387B is disposed so as to sandwich the first gear portion 373 of the movable member 310 between the second gear portion 381 and the second support roller 387B.

  As shown in FIG. 9, the movable member 310 of the present embodiment is configured such that the third surface 377 </ b> A has a fourth convex surface facing the first support roller 387 </ b> A in the portion of the main body 371 that contacts the support roller 387. The surface 377B has a convex surface toward the third support roller 387C. In the first support roller 387A of the present embodiment, the surface facing the third surface 377A of the movable member 310 has a concave surface toward the third surface 377. Similarly, the surface of the third support roller 387C that faces the fourth surface 377B of the movable member 310 has a concave surface toward the fourth surface 377B.

  The first member 378 of the movable member 310 includes a fifth surface 388 facing the direction opposite to the first surface 375 (the fifth surface 388 is assumed to be a virtual surface when the main body 371 is integrally formed), and the first surface 375. A sixth surface 389A and a seventh surface 389B connecting the outer edge of the fifth surface 388 and the outer edge of the fifth surface 388. The sixth surface 389A is a part of the third surface 377A, and the seventh surface 389B is a part of the fourth surface 377B. The sixth surface 389A located inward in the radial direction around the optical axis AX approaches the optical axis AX from the outer edge of the first surface 375 toward the outer edge of the fifth surface 388 (on the first support roller 387A). Inclined (to approach). The seventh surface 389B that is on the outer side in the radial direction centered on the optical axis AX is away from the optical axis AX from the outer edge of the first surface 375 toward the outer edge of the fifth surface 388 (on the third support roller 387C). Inclined (to approach).

  The second member 379 of the movable member 310 includes an eighth surface 390 facing the opposite direction of the second surface 376 (the sixth surface 390 is assumed to be a virtual surface when the main body 371 is integrally formed), and a second surface 376. A ninth surface 391A and a tenth surface 391B connecting the outer edge of the first surface 390 and the outer edge of the eighth surface 390. The eighth surface 390 of the second member 379 is joined to the fifth surface 388 of the first member 378 by adhesion, welding, or the like. The ninth surface 391A is a part of the third surface 377A, and the tenth surface 391B is a part of the fourth surface 377B. The ninth surface 391A located inside in the radial direction around the optical axis AX approaches the optical axis AX from the outer edge of the second surface 376 toward the outer edge of the eighth surface 390 (on the first support roller 387A). Inclined (to approach). The ninth surface 391B that is outside in the radial direction centered on the optical axis AX moves away from the optical axis AX from the outer edge of the second surface 376 toward the outer edge of the eighth surface 390 (on the third support roller 387C). Inclined (to approach).

  The adapter 300 of this embodiment includes a holding member 392 shown in FIG. 8 and a presser plate 393 shown in FIG. The holding member 392 is fixed to the first housing member 360. The holding member 392 is opposed to the presser plate 393 in the optical axis direction (Y-axis direction). The first support roller 387A, the second support roller 387B, the third support roller 387C, and the movable member 310 are disposed between the holding member 392 and the pressing plate 393 in the optical axis direction. In the first support roller 387A, the second support roller 387B, and the third support roller 387C, one end of each rotation shaft is rotatably supported by the holding member 392, and the other end of each rotation shaft is the presser plate 393. Is rotatably supported.

  The movable member 310 has a gap between the holding member 392 and the presser plate 393 between the holding member 392 and the presser plate 393 so as not to prevent the rotation in the circumferential direction about the optical axis AX. It is. Movement of the movable member 310 in the optical axis direction (Y-axis direction) is restricted by being sandwiched between the holding member 392 and the pressing plate 393.

  By the way, when the movable member is provided on the entire circumference in the circumferential direction centering on the optical axis of the interchangeable lens 200, the power of the drive device required for rotating the adapter increases. There is a possibility of becoming large. In addition, when the movable member is provided on the entire circumference in the circumferential direction centering on the optical axis of the interchangeable lens 200, the adapter may have a complicated mechanism for supporting the movable member, and the adapter may be large. is there.

  In the adapter 300 of this embodiment, since the movable member 310 is provided in a part of the circumferential direction centering on the optical axis AX of the interchangeable lens 200, the movable member 310 can be reduced in weight. Therefore, the adapter 300 can reduce the power required for the driving device 320 to rotate the movable member 310, and can reduce the device size. Further, since the adapter 300 is provided with a part of the movable member 310 in the circumferential direction centering on the optical axis AX of the interchangeable lens 200, the mechanism for supporting the movable member 310 can be simplified and the size of the apparatus can be reduced. Can be reduced in size.

  In the present embodiment, the pin 363 has a distance L3 from the optical axis AX in the radial direction centered on the optical axis AX in the second range A2 outside the first range A1 in the circumferential direction centered on the optical axis AX. Is arranged at a position substantially equal to the distance L1 between the optical axis AX and the movable member 310. Therefore, the adapter 300 can reduce the size of the adapter 300 in the radial direction around the optical axis AX while suppressing the movable member 310 from interfering (collision) with the pin 363, and the apparatus size can be reduced. can do.

  In the present embodiment, the second terminal portion 330 has the optical axis AX in the radial direction centered on the optical axis AX in the second range A2 excluding the first range A1 in the circumferential direction centered on the optical axis AX. The distance L2 is disposed at a position substantially equal to the distance L1 between the optical axis AX and the movable member 310. Therefore, the adapter 300 can reduce the dimension of the adapter 300 in the radial direction around the optical axis AX while suppressing the movable member 310 from interfering with (collising with) the second terminal portion 330, thereby reducing the device size. It can be made small.

  By the way, the movable member may cause a dimensional error in the direction of the optical axis to the extent that the movable member interferes with the holding member or the pressing plate with the rotation. Further, when the movable member is annular, the adapter may be prevented from rotating by the distortion of the shape of the movable member due to manufacturing error or the like.

  In the adapter 300 according to the present embodiment, the movable member 310 is provided in a part of the circumferential direction of the optical axis AX of the interchangeable lens 200, so that the rotation of the movable member 310 is hindered by a manufacturing error of the movable member 310. Can be prevented.

  FIG. 11 is a plan view showing a modification of the adapter of the present embodiment. The support roller 387 illustrated in FIG. 11 includes a fourth support roller 387D and a fifth support roller 387E. The fourth support roller 387D is disposed on the outer side with respect to the movable member 310 in the radial direction centered on the optical axis AX. The fourth support roller 387D is disposed in the tangential direction of the pitch circle 380 at a position where the first gear portion 373 of the movable member 310 and the second gear portion 381 of the driving device 320 are in contact with each other. The fifth support roller 387E is disposed on the inner side with respect to the movable member 310 in the radial direction centered on the optical axis AX. The fifth support roller 387E is disposed so that the movable member 310 is sandwiched between the fifth support roller 387E and the fourth support roller 387D.

  In the adapter of the modification, the fourth support roller 387D is disposed in the tangential direction of the pitch circle 380 at a position where the first gear portion 373 of the movable member 310 and the second gear portion 381 of the driving device 320 are in contact with each other. Therefore, the adapter can prevent the rotation of the movable member 310 by the fourth support roller 387D.

Here, the drive system of the movable member 310 (having the drive device 320 and the first gear portion 373 of the movable member 310) will be described in more detail with reference to the drawings of FIGS.
FIG. 12 is a mechanism diagram schematically showing a drive system of the movable member 310.
The actuator 383 is composed of a stepping motor, and is arranged so that the axis of the output shaft 400 of the actuator 383 is substantially parallel to the optical axis AX of the interchangeable lens 200. A drive gear 401 fixed to the end of the output shaft 400 of the actuator 383 is engaged with a first reduction gear 403 fixed to one end of a rotating shaft 402 whose axis is disposed substantially parallel to the optical axis AX. A second reduction gear 404 is fixed to the other end of the rotating shaft 402, and a third reduction gear 405 is engaged with the second reduction gear 404. The third reduction gear 405 is connected to the fourth reduction gear 407 disposed on the same extension as the third reduction gear 405 via the friction coupling portion 406.

  The friction coupling portion 406 will be described in detail with reference to FIG. The fourth reduction gear 407 has a disk-like flange portion 407 a having a diameter larger than the gear teeth of the fourth reduction gear 407 at the end portion (−Y side) close to the third reduction gear 405. . The friction coupling portion 406 has one end fixed to the third reduction gear 405 and a drive side rotation shaft 408 whose axis is disposed substantially parallel to the optical axis AX, and one end fixed to the flange portion 407a of the fourth reduction gear 407. A driven-side rotating shaft 409 having a core arranged substantially parallel to the optical axis AX, and a spring 410 having one end fixed to the flange portion 407a of the fourth reduction gear 407 and the other end wound around the driving-side rotating shaft 408. Yes. The axis of the driven side rotating shaft 409 is on an extension line of the axis of the driving side rotating shaft 408, that is, the driving side rotating shaft 408 and the driven side rotating shaft 409 are arranged on the same axis. The driving side rotation shaft 408 has a hollow cylindrical portion 411 at the end opposite to the third reduction gear 405 (+ Y side), and the driven rotation shaft 409 is rotatably inserted into the cylindrical portion 411. . (The inner diameter of the cylindrical portion 411 is larger than the diameter of the driven-side rotating shaft 409, so that the spring 410 can rotate.) The spring 410 has a coil portion 412 wound around the outer periphery of the cylindrical portion 411 of the driving-side rotating shaft 408, A connecting portion 413 extending linearly from one end of the portion 412 in a direction approaching the fourth reduction gear 407 (+ Y direction) and connected to the flange portion 407a of the fourth reduction gear 407. Note that the other end of the coil portion 412 is a free end and is slidable with respect to the outer peripheral surface of the cylindrical portion 411. The inner diameter of the coil portion 412 before being attached to the cylindrical portion 411 is smaller than the outer diameter of the cylindrical portion 411. Therefore, in a state where the coil part 412 is mounted on the outer periphery of the cylindrical part 411, a frictional force acts on the outer peripheral surface of the cylindrical part 411 from the coil part 412.

  Usually, the driving side rotating shaft 408 and the driven side rotating shaft 409 are integrally rotated synchronously by the frictional force. However, for example, when the fourth reduction gear 407 cannot rotate due to an external force and the third reduction gear 405 is subjected to a torque larger than the frictional force, the coil portion 412 has the cylindrical portion 411 of the drive side rotation shaft 408. By slipping the outer peripheral surface, the drive side rotation shaft 408 and the driven side rotation shaft 409 rotate relative to each other (the drive side rotation shaft 408 rotates idly with respect to the driven side rotation shaft 409). In other words, the third reduction gear 405 and the fourth reduction gear 407 rotate relative to each other (the third reduction gear 405 rotates idly with respect to the fourth reduction gear 407). That is, the friction coupling portion 406 prevents excessive power from the third reduction gear 405 from being transmitted to the fourth reduction gear 407.

As shown in FIG. 12, the fourth reduction gear 407 is engaged with a fifth reduction gear 415 fixed to one end of a rotation shaft 414 having an axial center disposed substantially parallel to the optical axis AX. A sixth reduction gear 416 is fixed to the other end of the rotation shaft 414. The sixth reduction gear 416 has a seventh reduction gear fixed to one end of a rotation shaft 417 whose axis is arranged substantially parallel to the optical axis AX. The reduction gear 418 is engaged. The first gear 385 described above is fixed to the other end of the rotating shaft 417, and the first gear 385 meshes with the first gear portion 373 of the movable member 310.
In the present embodiment, the drive gear 401, the first reduction gear 403, the second reduction gear 404, the third reduction gear 405, the fourth reduction gear 407, the fifth reduction gear 415, the sixth reduction gear 416, and the seventh reduction gear 418. The movable member 310 and the actuator 383 are connected by a gear train including the first gear 385 and the first gear portion 373, and the gear train constitutes a torque transmission path (power transmission path). The friction coupling portion 406 is provided on the front side.
The friction coupling portion 406 constitutes an excessive power transmission preventing portion that prevents excessive power from the actuator 383 side from being transmitted to the movable member 310 side in the gear train.

  Further, the fifth reduction gear 415 is engaged with a second gear 420 fixed to one end of a rotation shaft 419 having an axial center disposed substantially parallel to the optical axis AX. A slit disk 421 is fixed to the other end of the rotating shaft 419, and the encoder 384 described above is disposed facing the slit disk 421. In the present embodiment, the encoder 384 detects rotation information (rotation speed and rotation position) of the second gear 420. Instead of the encoder 384 formed of a photo interrupter, a contact sensor using a brush or a non-contact sensor that detects using magnetism may be used.

Further, the second gear 420 is engaged with a gear 423 that is fixed to one end of a rotating shaft 422 having an axial center disposed substantially parallel to the optical axis AX. The rotating shaft 422 is urged by the spring 424 in the clockwise direction as viewed from the + Y direction (in the −Y direction) as indicated by an arrow a in FIG. Due to the first biasing force from the spring 424, the movable member 310 is always biased in the clockwise direction as viewed from the + Y direction (in the −Y direction) as indicated by the arrow b. Then, the entire gear train is brought close to one direction and held by the detent torque of the stepping motor that is the actuator 383.
In the present embodiment, the second gear portion 381 includes the drive gear 401, the first reduction gear 403, the second reduction gear 404, the third reduction gear 405, the fourth reduction gear 407, the fifth reduction gear 415, and the sixth reduction gear. A gear 416, a seventh reduction gear 418, a first gear 385, a second gear 420, and a gear 423 are provided.

As shown in FIGS. 6 and 8, the first member 378 of the movable member 310 is provided with a light shielding portion 430.
The aperture driving member 203 of the interchangeable lens 200 is movable in a range where the aperture ratio of the aperture unit 202 changes from the maximum aperture ratio (open state) to the minimum aperture ratio. The aperture driving member 203 is urged in a direction (counterclockwise direction when viewed from the + Y direction) to reduce the aperture ratio of the aperture unit 202 by a second urging force from an urging member (not shown).

As shown in FIG. 14, the first contact portion 372 of the movable member 310 is in contact with the aperture driving member 203 of the interchangeable lens 200 from below (clockwise as viewed from the + Y direction). Therefore, the first contact portion 372 moves against the second urging force acting on the aperture driving member 203 when the aperture driving member 203 is moved so that the aperture ratio of the aperture of the interchangeable lens 200 is increased. . When the aperture driving member 203 is positioned at a position corresponding to the maximum aperture ratio (the position of the movable member 310 in FIG. 5), the movable member 310 cannot move any further. The position of the movable member 310 at this time (second state of the movable member 310) is the maximum opening position described above.
In FIG. 14, a solid line indicates a state where the movable member 310 is positioned at the maximum opening position, and a two-dot chain line indicates a state where the movable member 310 is positioned at the minimum opening position.

  Here, it is assumed that the movable member 310 is moved in the direction of increasing the aperture ratio by driving the actuator 383. Since the actuator 383 is controlled by the adapter control unit 350, the actuator 383 continues to be driven until a stop command is issued from the adapter control unit 350. When the movable member 310 reaches the maximum opening position, the movable member 310 cannot move beyond the maximum opening position as described above.

When the movable member 310 stops, the rotation of the first gear 385 that meshes with the first gear portion 373 of the movable member 310 stops. Of the above-described gear train of the driving device 320, the seventh reduction gear 418, the sixth reduction gear 416, the fifth reduction gear 415, and the fourth reduction gear 407 also stop rotating and mesh with the fifth reduction gear 415. Since the rotation of the second gear 520 is also stopped, the slit disk 421 also stops rotating. When the rotation of the slit disk 421 stops, the pulse of the encoder 384 is not detected. Accordingly, when the pulse of the encoder 384 is not detected when the actuator 383 is driven to move the movable member 310 toward the maximum opening position, it is determined that the movable member 310 has reached the maximum opening position. And the maximum opening position can be accurately detected.
On the other hand, even if the movable member 31 reaches the maximum opening position and stops, as long as the actuator 383 is driven, the drive gear 401, the first reduction gear 403, the second reduction gear 404, and the third reduction gear are included in the gear train. The gear 405 does not stop rotating. This is because the driven-side rotary shaft 409 connected to the fourth reduction gear 407 and the drive-side rotary shaft 408 connected to the third reduction gear 405 are connected so as to be relatively rotatable as described above. . That is, the third reduction gear 405 and the fourth reduction gear 407 are configured to be relatively rotatable. That is, when the coil portion 412 slips, torque transmission from the actuator 383 to the movable member 310 is suppressed, so that the actuator 383 is not overloaded.

  Then, the adapter control unit 350 uses the maximum opening position of the first contact unit 372 as a reference position for the aperture control of the interchangeable lens 200, and moves the first contact unit 372 from there to a position corresponding to the aperture command value F. . In order to move the first contact portion 372 to a position corresponding to the aperture command value F, the adapter control unit 350 rotates the movable member 310 by pulse-controlling the actuator 383 (stepping motor).

For example, if the drive amount of 1 Av is 12 pulses, when the aperture is reduced by 2 Av from the full aperture, the actuator 383 is driven in the narrowing direction by (m + 24) pulses, and the throttled state is maintained by the detent torque of the stepping motor that is the actuator 383. To do. Note that m is a correction term for correcting the driving amount from the wide open aperture, and corrects the interlocking error between the gear train of the driving device 320 and the friction coupling unit 406.
Further, in order to narrow down 3 Av from this state, the actuator 383 is driven by 36 pulses in the narrowing direction.
Subsequently, when opening 1 Av, the actuator 383 is driven by (12 + n) pulses toward the open side of the diaphragm. Note that n is a correction term for correcting a difference in driving direction, and corrects an interlocking error in the driving device 320.

The operation of the movable member 310 when the adapter 300 is turned on and off will be described.
When the adapter 300 is turned off, the first contact portion 372 is assumed to be in the retracted position.
When a power switch (not shown) of the camera body 100 is turned on, the power of the adapter 300 is turned on.
The adapter control unit 350 of the adapter 300 to which power is supplied acquires lens data (including information on the aperture stop of the interchangeable lens 200) from the interchangeable lens 200, and further executes initialization processing for the first contact unit 372. This initialization process is a process in which the first contact portion 372 (movable member 310) is once driven to the maximum opening position and this position is set as a reference position for aperture control.

The encoder 384 detects whether or not the first contact portion 372 has reached the maximum opening position. That is, when the actuator 383 is started and the movable member 310 is rotated, the pulse of the encoder 384 is detected until the first contact portion 372 reaches the maximum opening position. When the first contact portion 372 reaches the maximum opening position and the movable member 310 stops, as described above, in the drive device 320, the driven gears (the fourth reduction gear 407, the fifth reduction gear 415, The sixth reduction gear 416, the seventh reduction gear 418, and the first gear 385) stop rotating. Therefore, the slit disk 421 also stops rotating, and the pulse of the encoder 384 is not detected. The adapter controller 350 determines that the first contact portion 372 (movable member 310) is positioned at the maximum opening position when the encoder 384 pulse is no longer detected. In the present embodiment, the encoder 384 constitutes a detection unit that detects switching of the movable member 310 from the movable state to the stopped state.
Thus, when the pulse of the encoder 384 is no longer detected, it is determined that the movable member 310 is positioned at the maximum aperture position, and the maximum aperture position is detected, so that the interchangeable lens 200 is replaced with another interchangeable lens 200 having a different open aperture position. Even when they are replaced with each other, the maximum opening position of the movable member 310 can be accurately detected.

  Then, after the pulse of the encoder 384 is no longer detected, the adapter controller 350 drives the actuator 383 by a predetermined pulse (for example, 10 pulses) with the drive pulse, and then stops the drive pulse of the actuator 383. That is, after detecting the stop of the first contact portion 372 (movable member 310) (stop by reaching the maximum opening position of the movable member 310), it is delayed by a predetermined time (a time corresponding to the predetermined pulse), The drive of the actuator 383 is stopped.

  Since the actuator 383 continues to be driven during this delay time, the gears on the drive side of the friction coupling portion 406 (the drive gear 401, the first reduction gear 402, the second reduction gear 404, and the third reduction gear 405) It continues to rotate. Here, as described above, since the friction coupling portion 406 is provided between the third reduction gear 405 and the fourth reduction gear 407, the torque of the actuator 383 causes the friction force between the coil portion 412 and the cylindrical portion 411. Is larger than that, the coil portion 412 slips on the outer peripheral surface of the cylindrical portion 411 of the driving side rotating shaft 408, whereby the driving side rotating shaft 408 rotates relative to the driven side rotating shaft 409. That is, the third reduction gear 405 rotates relative to the stopped fourth reduction gear 407. Thereby, an overload is not added to the stepping motor which is the actuator 383.

  Thereafter, as described above, the adapter control unit 350 controls the actuator 383 according to the aperture command value F with the maximum opening position of the first contact portion 372 as a reference position, and moves the first contact portion 372 in the narrowing direction. The aperture control to be moved is executed.

  On the other hand, when a power switch (not shown) of the camera body 100 is turned off, the adapter control unit 350 controls the actuator 383 to drive the actuator 383 and move the first contact unit 372 (movable member 310) to the retracted position. To do. Thereafter, the power supply of the adapter 300 is turned off.

In the adapter 300 of this embodiment, the encoder 384 detects that the movable member 310 has reached the maximum opening position and stopped, and then the actuator 383 is stopped after a predetermined time, so that the maximum opening position of the movable member 310 is reached. Can be accurately and reliably detected.
Moreover, even when the interchangeable lens 200 is replaced with another interchangeable lens 200 having a different open aperture position, the maximum opening position of the movable member 310 can be accurately detected.

  In addition, since the friction coupling portion 406 is provided on the torque transmission path from the actuator 383 to the movable member 310, the coil portion 412 rotates relative to the cylindrical portion 411 of the drive side rotating shaft 408 in the friction coupling portion 406. Thus, torque transmission from the actuator 383 to the movable member 310 is suppressed, and an overload can be prevented from being applied to the actuator 383.

  In the adapter 300 of the present embodiment, the friction coupling portion 406 is configured by the drive side rotation shaft 408, the driven side rotation shaft 409, and the spring 410, so that the structure is simple, and the size and weight can be reduced. .

The present invention is not limited to the above-described embodiment as long as the characteristics of the present invention are not impaired, and other forms can be adopted within the scope of the technical idea of the present invention.
For example, the excessive power transmission preventing unit that prevents transmission of excessive power from the drive unit side to the movable member side is not limited to the configuration of the above embodiment, and a gear that connects the movable member and the drive unit. A ratchet mechanism may be provided between the movable member side and the drive portion side in the row, or a spring or an elastic body may be sandwiched between the movable member side and the drive portion side in the gear row.

DESCRIPTION OF SYMBOLS 1 ... Camera system, 100 ... Camera body, 200 ... Interchangeable lens, 203 ... Diaphragm drive member, 300 ... Adapter, 310 ... Movable member, 372 ... 1st contact part , 373 ... 1st gear part, 381 ... 2nd gear part, 383 ... Actuator, 384 ... Encoder, 401 ... Drive gear, 403 ... 1st reduction gear, 404 ... Second reduction gear, 405, third reduction gear, 406, friction connecting portion, 407, fourth reduction gear, 408, drive side rotating shaft, 409, driven side rotating shaft, 410 ... Spring, 415 ... 5th reduction gear, 416 ... 6th reduction gear, 418 ... 7th reduction gear, AX ... Optical axis

Claims (5)

An adapter that connects an interchangeable lens having a diaphragm whose aperture ratio changes by moving a diaphragm driving member, and a camera body,
A movable part for moving the aperture driving member;
A drive unit for moving the movable unit;
A connecting portion capable of transmitting a driving force of the driving portion to the movable portion and changing a force transmitted to the movable portion;
A detection unit for detecting that the movable unit is moving; and
Have
In a state where the force transmitted by the connecting part to the movable part is changed and reduced, the detection unit no longer detects the movement of the movable part, so that the diaphragm driving member is in the open aperture position. Adapter to judge . The connecting portion has a member that transmits a force by friction, and when the driving force of the driving portion becomes larger than the frictional force of the member, the force that the connecting portion transmits to the movable portion changes as the member slips. The adapter of claim 1, wherein the adapter decreases . The adapter according to claim 1 or 2, wherein the aperture ratio of the aperture becomes maximum when the aperture drive member is at the open aperture position . A drive control unit for controlling the drive unit;
The drive control unit stops the drive unit when the detection unit stops detecting the movement of the movable unit in a state where the force transmitted from the connecting unit to the movable unit is changed and decreased. The adapter as described in any one of. The adapter according to any one of claims 1 to 4 ,
A camera body connected to the adapter;
An interchangeable lens having an aperture drive member, the aperture drive member being in contact with the movable member of the adapter;
A camera system comprising:

Images