JP2019128455A - Light-amount adjustment device - Google Patents

Abstract

To provide a light-amount adjustment device that can excellently drive aperture blades.SOLUTION: A light-amount adjustment device comprises: an aperture blade that gets in and out of a route through which light from a subject goes; a stationary member that has a first opening part where an opening diameter is controlled by the aperture blade formed; a drive ring that is located on a side opposite the stationary member across the aperture blade, has a second opening part where the opening diameter is controlled by the aperture blade formed, and drives the aperture blade; and a slide part that is provided in at least one of the stationary member or the drive ring, and abuts with the aperture blade when controlling the opening diameter of the aperture blade. The slide part includes a toric protrusion part that includes at least one opening end of the first and second opening parts, protrudes in an optical axis direction, and is formed into a circular shape. The toric protrusion part is configured to support one end part of the aperture blade when the aperture blade is fully opened.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a light amount adjusting device such as an aperture device or a shutter of an interchangeable lens of a camera.

  For example, the stop device of the interchangeable lens has a fixed stop through which light from an object passes and a variable stop having a plurality of stop blades for changing the aperture diameter of the fixed stop. Since the plurality of diaphragm blades are attached in a state of being partially overlapped with each other, the diaphragm blades are in sliding contact with each other when adjusting the aperture diameter. Further, the plurality of diaphragm blades also contact peripheral members such as a fixed diaphragm and a drive ring. For this reason, in a diaphragm device including a plurality of diaphragm blades, static electricity due to friction is likely to occur.

JP 2016-122057 A

  When static electricity is generated in the diaphragm device, the diaphragm blades and peripheral members may be charged, and the diaphragm blades may be attracted to each other by static electricity, or the diaphragm blades may be adsorbed to the peripheral members. In this case, the load on the motor that drives the diaphragm blades increases, making it difficult to control the variable diaphragm. For this reason, it is common to provide a rail for sliding the diaphragm blade on the side of the peripheral member facing the diaphragm blade so as to reduce the contact area of the peripheral member that contacts the diaphragm blade.

  However, if a rail protruding toward the diaphragm blade is provided, the portion of the diaphragm blade not in contact with the rail may be biased in a direction approaching the peripheral member by static electricity, and the diaphragm blade may be warped at this region. . If the diaphragm blades are warped, the load on the motor becomes large and it becomes difficult to drive the diaphragm blades.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a light amount adjusting device capable of driving the diaphragm blade well.

  One aspect of the light amount adjusting device of the present invention is a diaphragm blade that enters and exits a path through which light from a subject passes, a fixed member having a first opening whose opening diameter is controlled by the diaphragm blade, and a diaphragm blade A drive ring that is positioned on the opposite side of the fixed member with the aperture interposed therebetween, the opening diameter of which is controlled by the aperture blade, and driving the aperture blade, and at least one of the fixed member or the drive ring And a sliding portion that contacts the diaphragm blade when controlling the aperture diameter of the diaphragm blade. The sliding portion includes an annular projecting portion formed in an annular shape projecting in the optical axis direction including at least one open end of the first and second openings. The annular projecting portion supports one end of the diaphragm blade when the diaphragm blade is fully opened.

  ADVANTAGE OF THE INVENTION According to this invention, the light quantity adjustment apparatus which can drive a diaphragm blade favorably can be provided.

FIG. 1 is a cross-sectional view illustrating an interchangeable lens including an aperture device according to the embodiment. 2 is an exploded perspective view of the diaphragm device of FIG. FIG. 3 is a front view showing a blade driving plate of the diaphragm device of FIG. 4 is a rear view showing the blade driving plate of FIG. FIG. 5 is a side view showing the blade driving plate of FIG. FIG. 6 is a front view of the diaphragm device of FIG. 1 as viewed from the front. FIG. 7 is a rear view of the structure of the throttling device of FIG. 1 from which the blade pressing plate is removed, as viewed from the rear. FIG. 8 is a front view of the blade pressing plate of the diaphragm device of FIG. 1 as viewed from the front. FIG. 9 is a partially enlarged cross-sectional view showing a main part of the diaphragm device of FIG. FIG. 10 is a cross-sectional view showing a conventional example of a diaphragm device as compared with FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of an interchangeable lens 100 including an aperture device 10 according to an embodiment of a light amount adjusting device of the present invention. The interchangeable lens 100 has a lens barrel 101 accommodating a plurality of lenses. The plurality of lenses are provided coaxially along the optical axis O of the interchangeable lens 100. The aperture device 10 controls the amount of light incident on an image sensor (not shown) of a camera body (not shown) by adjusting the aperture diameter of a path through which light from a subject (not shown) passes.

  In the following description, the direction from the camera body (not shown) toward the subject (not shown) will be referred to as the front, and the opposite will be referred to as the back. In each figure, the direction in which the light from the subject is directed to the image sensor of the camera body is shown as an arrow L.

  As shown in FIG. 2, the diaphragm device 10 includes a base member 20, a blade drive plate 30 (drive ring), a blade assembly 40, and a blade presser plate 50 (fixing member) from the front to the rear along the arrow L. ) Overlapping. The base member 20 has a circular opening 21 that is a part of a path through which light passes. An annular housing recess 22 is provided on the rear surface of the base member 20. The housing recess 22 is coaxially provided outside the opening 21.

  The accommodation recess 22 rotatably accommodates the blade drive plate 30 and movably accommodates the plurality of diaphragm blades 41 of the blade assembly 40. A blade pressing plate 50 is fixed to the rear surface of the housing recess 22 by a plurality of screws 52. The vane pressure plate 50 has a circular opening 51 (first opening) that is a part of the light passage path. The blade pressing plate 50 presses the rear side of the blade assembly 40 disposed in the accommodation recess 22 of the base member 20.

  3 is a front view of the blade driving plate 30 as viewed from the front, FIG. 4 is a rear view of the blade driving plate 30 as viewed from the rear, and FIG. 5 is a side view of the blade driving plate 30. The blade drive plate 30 has a circular opening 31 (second opening) that is a part of a path through which light passes. The opening 31 is coaxial with the opening 21 of the base member 20 and the opening 51 of the blade pressing plate 50 in a state where the base device 20, the blade driving plate 30, and the blade pressing plate 50 are stacked to assemble the diaphragm device 10. Overlap. That is, the three openings 21 31 and 51 are circular openings having substantially the same diameter, and the opening 31 with the smallest opening diameter (see FIG. 9) functions as a fixed diaphragm of the diaphragm device 10.

  The blade driving plate 30 includes an arc-shaped rack 32 near the outer periphery in front of it. The rack 32 is curved with the same curvature as the blade drive plate 30, and has gear teeth 32a on the outer peripheral side. On the other hand, a motor 60 (FIG. 2) for rotating the blade driving plate 30 is fixed to the base member 20. A pinion may be attached to a rotating shaft (not shown) of the motor 60 via a pulley, a toothed belt, or the like.

  The motor 60 is, for example, a stepping motor, and its rotation amount is controlled with high accuracy. Further, the motor 60 can rotate in both forward and reverse directions. When the blade drive plate 30 is rotated in one direction (counterclockwise direction as viewed from the front), the plurality of diaphragm blades 41 of the blade assembly 40 move in the direction in which the aperture diameter decreases, and the blade drive plate 30 When it is rotated in the other direction (clockwise direction as viewed from the front), the plurality of diaphragm blades 41 move in the direction in which the opening diameter is increased. Therefore, the opening diameter of the expansion device 10 can be controlled by controlling the rotation direction and the rotation amount of the motor 60.

  FIG. 6 is a front view of the diaphragm device 10 as viewed from the subject side. FIG. 6 shows a state in which the plurality of diaphragm blades 41 are opened to the maximum, that is, a state in which the aperture diameter of the diaphragm device 10 is maximized. In this state, the innermost edge 41 a of the plurality of diaphragm blades 41 of the blade assembly 40 is outside the openings 21, 31, 51.

  As shown in FIG. 4, a plurality of cam grooves 33 are provided on the rear surface of the blade driving plate 30. In this embodiment, since nine diaphragm blades 41 of the blade assembly 40 are provided, nine cam grooves 33 of the blade driving plate 30 are also provided. The nine cam grooves 33 are provided at an equal pitch along the circumferential direction of the blade driving plate 30. The cam groove 33 has a shape inclined from the inner peripheral side toward the outer peripheral side along the clockwise direction in FIG.

  Further, as shown in FIGS. 2 and 7, near the outer peripheral edge of the rear surface of the base member 20, a plurality of rotation shafts 23 serving as the rotation centers of the plurality of diaphragm blades 41 are provided. There is. Each rotating shaft 23 extends in parallel with the optical axis O toward the rear. These nine rotation shafts 23 are provided at equal intervals outside the accommodation recess 22 and along the circumferential direction. FIG. 7 illustrates a state in which one diaphragm blade 41 is attached to the rotation shaft 23.

  The diaphragm blades 41 are slidably inserted into the corresponding cam grooves 33 of the blade driving plate 30 (not shown) (behind the cam pins denoted by 43 in FIG. 7), and the corresponding rotation shafts 23 of the base member 20. And a pin hole 42 for rotatably receiving. The aperture blade 41 has a cam pin 43 that protrudes rearward toward the blade pressing plate 50. That is, the diaphragm blade 41 has two cam pins 43 (only a rear one is shown) protruding in the opposite direction from the same position on both surfaces thereof, and has one pin hole 42. In the following description, the same reference numeral 43 is also given to the cam pin provided in front of each diaphragm blade 41.

  As shown in FIG. 2, the blade assembly 40 is obtained by arranging a plurality of (in this embodiment, nine) diaphragm blades 41 having the same shape, partially overlapping each other in an annular shape. The pivot shaft 23 of the base member 20 is inserted into the pin hole 42 of each diaphragm blade 41, and the cam pin 43 of each diaphragm blade 41 is inserted into the cam groove 33 of the blade drive plate 30 as described above. The nine diaphragm blades 41 are attached at the same pitch and in the same posture along the rotation direction of the blade drive plate 30. Each diaphragm blade 41 pivots about the pivot shaft 23 to move in and out of the path through which light from the subject passes.

  As shown in FIG. 8, on the front surface of the blade holding plate 50, a plurality of cam grooves 53 through which the cam pins 43 on the rear of the corresponding diaphragm blades 41 are slidably inserted are provided. In this embodiment, since nine diaphragm blades 41 of the blade assembly 40 are provided, nine cam grooves 53 of the blade pressing plate 50 are also provided. The nine cam grooves 53 are provided at an equal pitch along the circumferential direction of the blade pressing plate 50.

  Further, near the outer peripheral edge of the front surface of the blade pressing plate 50, pin receiving holes 54 through which the corresponding rotation shafts 23 of the base member 20 are inserted are provided. These nine pin receiving holes 54 are provided at equal intervals along the circumferential direction of the blade pressing plate 50. Each cam groove 53 is provided in an arc shape centering on the corresponding pin receiving hole 54.

  When driving the expansion device 10 having the above-described structure, the motor 60 is biased to rotate the blade drive plate 30 in a desired direction. When the blade drive plate 30 rotates, the cam pins 43 of the diaphragm blades 41 slide along the plurality of cam grooves 33 of the blade drive plate 30, and the cam pins 43 move toward the center of the blade drive plate 30 or the outer periphery. Move to The moving direction of the cam pin 43 varies depending on the rotation direction of the motor 60.

  When the cam pin 43 of each diaphragm blade 41 moves in the radial direction of the blade driving plate 30, each diaphragm blade 41 rotates about the rotation shaft 23. For example, when the blade drive plate 30 is rotated clockwise when the diaphragm device 10 is viewed from the front, the cam pins 43 of the diaphragm blades 41 move radially outward, and the diaphragm blades 41 center on the pivot shaft 23. It turns in the direction of closing the opening. Conversely, when the blade drive plate 30 is turned counterclockwise when the diaphragm device 10 is viewed from the front, the cam pins 43 of the diaphragm blades 41 move radially inward, and the diaphragm blades 41 rotate the pivot shaft 23. Rotate in the direction of opening the opening to the center.

  Since the plurality of diaphragm blades 41 of the blade assembly 40 move (rotate) in a state where they overlap each other, they are slid in contact with each other. The plurality of diaphragm blades 41 contact the peripheral members, that is, the blade driving plate 30 and the blade pressing plate 50 in the middle of the rotation. For this reason, in the diaphragm device 10 having the plurality of diaphragm blades 41, static electricity is easily generated due to the friction caused by the sliding contact between the members.

  When static electricity is generated in the diaphragm device 10, the diaphragm blades 41 are charged, and the diaphragm blades 41 may be adsorbed by static electricity, or the diaphragm blades and peripheral members may be adsorbed by static electricity. In this case, the movement of the diaphragm blade 41 becomes difficult, the load on the motor 60 becomes large, and there is a possibility that normal diaphragm control can not be performed. For example, in such a case, the stop position accuracy of the diaphragm blade 41 becomes low, and it becomes difficult to control the aperture value to a normal value.

  For this reason, in the present embodiment, the rear surface (FIG. 4) of the blade drive plate 30 which may come into contact with the plurality of diaphragm blades 41 of the blade assembly 40, and the front surface (FIG. In 8), a sliding portion 70 for reducing the contact area between the diaphragm blades 41 is provided. The sliding portion 70 is a rib-like projection that protrudes toward the blade assembly 40 from the rear surface of the blade drive plate 30, and protrudes toward the blade assembly 40 from the front surface of the blade pressing plate 50. Rib-shaped projections. In order to reduce the contact area with the diaphragm blade 41, the cross-sectional shape of the projecting end of the sliding portion 70 is desirably convex. The plurality of diaphragm blades 41 move with both surfaces in contact (abutment) with the projecting end of the sliding portion 70.

  As shown in FIG. 4, the sliding portion 70 provided on the rear surface of the blade drive plate 30 includes an annular projecting portion 71, an outer peripheral side projecting portion 72, and an intermediate projecting portion 73. The annular projecting portion 71, the outer peripheral projecting portion 72, and the intermediate projecting portion 73 are connected (connected) along the rear surface of the blade driving plate 30. It projects at the same height from the surface. Alternatively, the annular protruding portion 71 may have a portion slightly higher in projecting height than the outer peripheral side protruding portion 72 and the middle protruding portion 73.

  The annular projecting portion 71 is provided at the edge of the opening 31 of the blade drive plate 30, and is formed in an annular shape that protrudes in the direction of the optical axis O including the opening end. The annular projecting portion 71 is a state in which the plurality of aperture blades 41 are rotated to a position where the aperture diameter of the aperture device 10 is maximized (the state shown in FIGS. 6 and 7). It is disposed at a position where it can contact the edge 41a on the 31 side, that is, one end 41a (FIG. 7) close to the optical axis O of each aperture blade 41.

  The annular protrusion 71 does not necessarily have an annular shape, and a part of the circumferential direction may be divided or divided into a plurality of parts. In this case, for example, the interval may be made smaller than the thickness of the diaphragm blades 41 so that the edge of the diaphragm blades 41 does not get caught in this divided part when moving. Alternatively, the annular projecting portion 71 may be a regular polygon having a relatively large number of corners. In any case, the annular projecting portion 71 may be any as long as it can contact and support the edge 41 a on the inner peripheral side of the diaphragm blade 41 rotated to the fully open position.

  Further, the annular projecting portion 71 is not necessarily required at the edge of the opening 31. In terms of design, even if the annular projecting portion 71 is provided at the edge of the opening 31, for example, the annular projecting portion 71 may be provided just at the edge of the opening 31 due to an error in manufacturing the blade drive plate 30. It is conceivable that you can not In the present specification and claims, it is assumed that the annular projecting portion 71 is provided at the edge of the opening 31 even in the case of having a deviation based on such an error.

  In general, the maximum aperture diameter of the variable aperture when the aperture blades 41 of the blade assembly 40 are fully opened is slightly smaller than the aperture size of the fixed aperture defined by the aperture 31 of the blade drive plate 30. Designed to be large. Therefore, even if the annular protrusion 71 is provided slightly outside the edge of the opening 31, the edge 41a of the fully opened diaphragm blade 41 can be supported by the annular protrusion 71.

  FIG. 9 is a partially enlarged cross-sectional view of a main part of the diaphragm device 10 of the present embodiment. FIG. 9 also shows the diaphragm blade 41 in a state where the opening diameter is maximized. According to this, it can be seen that the edge 41 a on the inner peripheral side of the fully opened diaphragm blade 41 is opposed to the annular projection 71 provided at the edge of the opening 31 of the blade drive plate 30. Ideally, as shown in FIG. 9, it is desirable that the diaphragm blade 41 moves in a non-contact state with respect to the blade driving plate 30 and the blade pressing plate 50. However, the diaphragm blade 41 may contact the blade driving plate 30 or the blade pressing plate 50 during movement.

  Returning to FIG. 4, the outer peripheral protrusion 72 of the sliding portion 70 is provided in an annular shape that protrudes in the direction of the optical axis O along the outer peripheral edge of the blade driving plate 30. Similarly to the annular projecting portion 71 described above, the outer circumferential projecting portion 72 does not necessarily have to be provided on the outer peripheral edge, and need not be annular. The outer peripheral side protruding portion 72 slidably contacts each rotating diaphragm blade 41 to guide the movement of the diaphragm blade 41, and each diaphragm blade 41 is rotated to a position where the opening is fully opened. It arrange | positions in the position which supports the other end part of the blade | wing 41. FIG.

  The intermediate projecting portion 73 contacts each of the rotating diaphragm blades 41 between the annular projection 71 and the outer peripheral projection 72 described above to guide the movement of the diaphragm blades 41. A plurality of (intermediately in this embodiment) intermediate protrusion portions 73 are provided corresponding to the plurality of cam grooves 33 of the blade drive plate 30. More specifically, each intermediate protrusion 73 is provided so as to surround the outer peripheral edge of the corresponding cam groove. As a result, the edge of the diaphragm blade 41 can be made less likely to be caught by the intermediate projecting portion 73, and the movement of the diaphragm blade 41 can be made smooth.

  Since the intermediate projecting portion 73 is provided along the moving direction of the diaphragm blade 41 (the direction in which the cam groove 33 extends), the contact area between the intermediate projecting portion 73 and the diaphragm blade 41 should be reduced. The frictional resistance between the two can be reduced, and the movement of the aperture blade 41 can be improved. Normally, the sliding portion 70 is provided along the moving direction of the aperture blade 41 as described above.

  On the other hand, the annular projecting portion 71 provided at the edge of the opening 31 extends in the direction intersecting the moving direction of each aperture blade 41, and the aperture blade 41 in motion and the annular projecting portion 71 The contact area between the two becomes relatively large, which prevents the frictional resistance between them from being sufficiently reduced. However, since the annular projecting portion 71 can contact and support the edge 41 a of each aperture blade 41 located at the edge of the opening 31 in a state where the aperture blade 41 is fully opened, Warpage at this portion can be prevented.

  That is, as in the present embodiment, when the sliding portion 70 in contact with the diaphragm blade 41 is provided, movement of the diaphragm blade 41 can be made smooth, but at a position where the sliding portion 70 does not 41 are drawn to the blade drive plate 30. As described above, when the suction force directed to the blade drive plate 30 acts on the diaphragm blade 41 at a portion where the sliding portion 70 is not present, the diaphragm blade 41 partially supported by the sliding portion 70 may be warped. There is.

  Temporarily, as shown in FIG. 10, instead of providing the annular protrusion 71 at the edge of the opening 31 of the blade drive plate 30, an annular protrusion 77 is provided at a position spaced outward from the opening 31. In this case, the edge 41 a of the diaphragm blade 41 supported by the protrusion 77 is curved in a direction approaching the blade drive plate 30 by static electricity on the opening 31 side of the protrusion 77. That is, when the annular protrusion 71 is not provided at the edge of the opening 31, there is a possibility that the edge 41a of the diaphragm blade 41 is warped in a state where the diaphragm blade 41 is disposed at a position where the diaphragm is fully opened. is there.

  Therefore, in the present embodiment, the annular projecting portion 71 opposed to the diaphragm blade 41 is provided at a portion where the warping may occur. Thereby, the warp of the diaphragm blade 41 can be prevented, and the movement of the diaphragm blade 41 can be made smooth. On the other hand, for example, as shown in FIG. 10, when the diaphragm blade 41 is warped, the diaphragm blade 41 easily contacts the blade drive plate 30 and the blade pressing plate 50, and the movement of the diaphragm blade 41 It will be disturbed.

  On the other hand, as shown in FIG. 8, the sliding part 70 provided on the blade pressing plate 50 includes an annular projecting part 74, an intermediate projecting part 75, and an intermediate projecting part 76. The relatively long intermediate projecting portion 75 and the annular projecting portion 74 are connected (connected) along the front surface of the vane pressure plate 50. The annular projecting portion 74, the intermediate projecting portion 75, and the intermediate projecting portion 76 project at the same height from the front surface of the vane pressure plate 50. Alternatively, the annular projecting portion 74 may have a portion whose projecting height is slightly higher than the intermediate projecting portions 75 and 76.

  The annular protrusion 74 is provided at the edge of the opening 51 of the blade pressing plate 50 and is formed in an annular shape including the opening end and protruding in the optical axis O direction. The annular projecting portion 74 is a state where the plurality of aperture blades 41 are rotated to a position where the aperture diameter of the aperture device 10 is maximized (the state shown in FIGS. 6 and 7). It is disposed at a position contacting the edge 41 a on the 51 side, that is, one end 41 a (FIG. 7) close to the optical axis O of each aperture blade 41.

  The annular protrusion 74 does not necessarily have an annular shape, and a part of the circumferential direction may be divided or divided into a plurality of parts. In this case, for example, the interval may be made smaller than the thickness of the diaphragm blades 41 so that the edge of the diaphragm blades 41 does not get caught in this divided part when moving. Alternatively, the annular projecting portion 74 may be a regular polygon having a relatively large number of corners. In any case, the annular projecting portion 74 may be any one as long as it can contact and support the edge 41 a on the inner peripheral side of the diaphragm blade 41 rotated to the fully open position.

  Further, the annular projecting portion 74 is not necessarily required at the edge of the opening 51. In terms of design, even if the annular projecting portion 74 is provided at the edge of the opening 51, the annular projecting portion 74 may be provided just at the edge of the opening 51 due to an error in manufacturing the blade pressing plate 50, for example. It is conceivable that you can not In the present specification and claims, it is assumed that the annular projecting portion 74 is provided at the edge of the opening 51 even in the case of having a deviation based on such an error.

  In addition, the maximum aperture diameter of the variable aperture when the plurality of aperture blades 41 of the blade assembly 40 is fully opened is slightly smaller than the aperture diameter of the fixed aperture normally defined by the aperture 51 of the vane pressure plate 50 Designed to be large. Therefore, even if the annular protruding portion 74 is provided slightly outside the edge of the opening 51, the edge 41 a of the fully open diaphragm blade 41 can be supported by the annular protruding portion 74. As shown in FIG. 9, it can be seen that the edge 41 a on the inner peripheral side of the fully open aperture blade 41 faces the annular projecting portion 74 provided at the edge of the opening 51 of the blade pressing plate 50.

  The intermediate protrusions 75 and 76 are provided in an arc shape with the corresponding pin receiving hole 54 as the center. That is, nine sets of intermediate protrusions 75 and 76 are provided in accordance with the number of diaphragm blades 41. The intermediate projecting portions 75 and 76 are in contact with the rotating diaphragm blades 41 to guide the movement of the diaphragm blades 41.

  More specifically, the shorter intermediate protrusion 76 is disposed adjacent to the pin receiving hole 54 and between the cam groove 53. Further, the longer intermediate protruding portion 75 is provided on the opposite side of the cam groove 53 with the shorter intermediate protruding portion 76. Since the intermediate protrusions 75 and 76 are provided along the moving direction of the diaphragm blade 41, the contact area with the diaphragm blade 41 can be reduced.

  Since the annular projecting portion 74 can support the edge 41a on the inner peripheral side of the fully opened aperture blade 41, like the annular projecting portion 71 of the blade drive plate 30 described above, the diaphragm blade 41 is supported. It is possible to prevent the problem of warping due to the adsorption force due to static electricity acting on the inner peripheral edge 41a.

  As described above, according to the present embodiment, the movement of each diaphragm blade 41 can be made smooth by the sliding portion 70, and static electricity can be less likely to be charged on the diaphragm blade 41. Moreover, according to the present embodiment, the annular protrusions 71 of the blade drive plate 30 and the annular protrusions 74 of the blade retainer plate 50 can support the inner peripheral edge 41a of each diaphragm blade 41. Even if static electricity is charged on the diaphragm blade 41, it is possible to prevent the edge 41a of the diaphragm blade 41 from being warped. Also, according to the present embodiment, static electricity is less likely to be charged in the diaphragm blade 41, so that the stop position accuracy when the diaphragm blade 41 is stopped can be improved, and the aperture value is less likely to change. That is, according to the present embodiment, the diaphragm blade 41 can be driven satisfactorily.

  In addition, this invention is not limited to embodiment mentioned above, It can change arbitrarily, without exceeding the scope of invention. For example, in the above-described embodiment, the cam groove 33 is provided in the blade driving plate 30 and the cam groove 53 is provided in the blade pressing plate 50. However, the cam groove 53 is provided in the blade driving plate 30 and the cam groove is formed in the blade pressing plate 50. 33 may be provided. In this case, it is necessary to make the sliding portion 70 reverse to the one provided on the blade drive plate 30 and the one provided on the blade pressing plate 50.

  In the embodiment described above, although the present invention is applied to the diaphragm device 10 incorporated in the interchangeable lens 100 of the camera, the present invention is not limited to this, and the present invention may be applied to a shutter device incorporated in the interchangeable lens 100. Can be applied.

  DESCRIPTION OF SYMBOLS 10 ... Diaphragm | restriction apparatus, 20 ... Base member, 21 ... Opening part, 30 ... Blade drive plate, 31 ... Opening part, 40 ... Blade assembly, 41 ... Diaphragm blade, 41a ... Edge, 50 ... Blade pressing plate, 51 ... Opening Parts 60 Motor 60 Sliding part 71 Annular projecting part 74 Annular projecting part 100 Interchangeable lens O Optical axis.

Claims (8)

An aperture blade that enters and leaves a path through which light from an object passes;
A fixing member formed with a first opening whose opening diameter is controlled by the diaphragm blade;
A drive ring that is located on the opposite side of the fixed member with the aperture blade interposed therebetween, and that forms a second opening whose aperture diameter is controlled by the aperture blade and drives the aperture blade;
A sliding portion that is provided on at least one of the fixing member or the drive ring and contacts the diaphragm blade when controlling the aperture diameter of the diaphragm blade;
The sliding portion includes an annular projecting portion formed in an annular shape that protrudes in the optical axis direction including at least one opening end of the first and second opening portions, and the annular projecting portion Is a light amount adjusting device that supports one end of the diaphragm blade when the diaphragm blade is fully opened. The sliding part is further
At least one of the first and second openings is formed on the outer peripheral side of at least one of the fixing member or the drive ring, and has the same height as the annular protrusion in the optical axis direction. When the diaphragm blades are fully opened, the outer peripheral side protruding portion that supports the other end of the diaphragm blades,
An intermediate for supporting the diaphragm blade between the annular protrusion and the outer peripheral protrusion when the diaphragm blade is fully opened at the same height as the annular protrusion in the optical axis direction. A protrusion,
The light quantity adjusting device according to claim 1, further comprising:   3. The light amount adjusting device according to claim 2, wherein the intermediate projecting portion is connected to the annular projecting portion and the outer peripheral side projecting portion. The intermediate projecting portion, the annular projecting portion, and the outer peripheral projecting portion are formed on the fixing member,
The fixing member is further formed with a cam for driving the diaphragm blades,
4. The light quantity adjusting device according to claim 3, wherein the intermediate protrusion is formed so as to surround an outer periphery of the cam. The intermediate projecting portion, the annular projecting portion, and the outer peripheral projecting portion are formed on the drive ring,
The drive ring is further formed with a cam for driving the diaphragm blades,
4. The light quantity adjusting device according to claim 3, wherein the intermediate protrusion is formed so as to surround an outer periphery of the cam. A plurality of holes are further formed in the fixing member or the drive ring on which the cam is formed,
6. The light quantity adjusting device according to claim 4, wherein the intermediate protrusions are arranged on both sides of each hole in a circumferential direction with respect to the optical axis center of the fixing member.   7. The light quantity adjusting device according to claim 1, wherein the annular projecting portion is divided into a plurality of pieces, and the distance between them is smaller than the thickness of the diaphragm blade. A variable stop having a plurality of stop blades that enter and leave a path through which light passes;
A fixed diaphragm having an opening that is disposed adjacent to the variable diaphragm along the path and whose opening diameter is controlled by the diaphragm blade;
The plurality of diaphragm blades extend in a direction intersecting the moving direction of the plurality of diaphragm blades, protrude toward the plurality of diaphragm blades, are provided at the edges of the opening of the fixed diaphragm, and the plurality of diaphragms are fully opened. A projecting portion which contacts the edge of the aperture side of the sheet of aperture blades;
A light amount adjusting device.