JP2017120312A - Lens barrel and imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for bearing a load in a well-balanced state from a subject side with a barrier blade open without entailing large-sizing of a lens barrel.SOLUTION: A lens barrel has a barrier cylinder 110 which rotatably retains a barrier drive ring 108 driving barrier blades 102-105 in closing and opening directions and also supports the barrier blades 102-105 rotatably in the opening and closing directions. On an outer peripheral side in the opening and closing directions of the barrier blade 105 most on the subject side among the barrier blades 102-105, there are provided projection parts 105d, 105e projecting to the opposite side from the subject side, and a projection part 105g arranged closer to a tip side of the barrier blade 105 than the projection parts 105d, 105e. When a load is placed on the barrier blade 105 from an optical-axis direction with the barrier blade 105 closed, the projection parts 105d, 105e are arranged overlapping in the optical-axis direction to abut on a subject-side end face of the barrier drive ring 108, and the projection part 105g is arranged overlapping in the optical-axis direction to abut on a subject-side end face of the barrier cylinder 110.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a lens barrel mounted on an imaging device such as a digital camera or a digital video camera, and an imaging device including the lens barrel.

  Some imaging devices such as digital cameras and digital video cameras have a barrier mechanism for covering the lens when the lens barrel is retracted. In general, the barrier mechanism is provided with a load receiver that receives a load from the object side when the barrier blade is closed, but the lens barrel has been downsized in response to the recent enlargement of the lens opening. It is difficult to secure a space for providing a mechanism for receiving the load.

  Therefore, by providing a barrier cover having a diameter larger than that of the barrier cylinder at the end of the barrier cylinder on the subject side, a space for storing the barrier blade provided with a load receiver that receives a load from the subject side when the barrier blade is closed is secured. Technology has been proposed (Patent Document 1).

JP-A-2015-135374

  However, in Patent Document 1, since the barrier cover having a larger diameter than that of the barrier cylinder is provided, the outer diameter of the lens barrel is increased, which causes an increase in the size of the lens barrel and an increase in the size of the camera. In addition, when the barrier cylinder cannot be fully retracted by providing a barrier cover having a diameter larger than that of the barrier cylinder, there is a concern that the retractable length becomes longer, and this also increases the size of the camera.

  Accordingly, an object of the present invention is to provide a technique capable of receiving a load received from the subject side in a balanced manner in a closed state of the barrier blade without causing an increase in the size of the lens barrel.

  In order to achieve the above object, a lens barrel according to the present invention includes a plurality of barrier blades rotatably provided in a direction to open and close a lens exposed to an object side through an opening, and the plurality of barrier blades A barrier driving ring that drives the barrier driving ring rotatably, and a barrier cylinder that rotatably supports the plurality of barrier blades in the opening and closing direction. Among the plurality of barrier blades, on the outer peripheral side in the opening and closing direction of the subject side barrier blade closest to the subject side, a first protruding portion that protrudes opposite to the subject side, and the first protruding portion A second protrusion is disposed on the tip side of the subject-side barrier blade, and the first protrusion is loaded on the subject-side barrier blade in the optical axis direction when the subject-side barrier blade is closed. Is added, The second projecting portion is disposed so as to be in contact with the end surface on the subject side of the barrier drive ring in the optical axis direction, and the second projecting portion is placed on the subject side barrier blade with the optical axis in the closed state. When a load from the direction is applied, the barrier cylinder is arranged so as to overlap with the subject-side end surface of the barrier cylinder in the optical axis direction.

  According to the present invention, it is possible to receive the load received from the subject side in a well-balanced state with the barrier blades closed, without increasing the size of the lens barrel.

It is a perspective view of a digital camera which is an example of an embodiment of an imaging device provided with a lens barrel of the present invention. It is a disassembled perspective view of a lens barrel. It is sectional drawing in the retracted position of a lens-barrel. It is sectional drawing in the imaging position of a lens-barrel. It is a disassembled perspective view of a 1st lens unit. It is a disassembled perspective view of a 5th lens unit. It is the figure which looked at the barrier mechanism in which a pair of barrier blades are closed from the subject side. It is the figure which looked at the barrier mechanism with a pair of barrier blades open from the subject side. It is the figure which looked at the barrier mechanism in which a pair of barrier blades are closed from the image plane side. It is the figure which looked at the barrier mechanism with a pair of barrier blades open from the image plane side. In the barrier mechanism in which a pair of barrier blades are in a closed state, FIG. 5 is a view of a state in which some of the barrier blades of a pair of barrier blades are removed from the subject side. It is the figure which looked at the state which removed the 1st group cap from the subject side in the barrier mechanism with a pair of barrier blades in an open state. It is a perspective view which shows the closed state of one barrier blade of a pair of barrier blades. It is a perspective view which shows the relationship in the open state of a barrier blade | wing and another barrier blade | wing. It is a side view of a barrier mechanism with a pair of barrier blades in a closed state. It is principal part sectional drawing explaining the relationship between the rail part of a barrier drive ring, and the rail part of a 1st group lens barrel. It is sectional drawing which shows the relationship between an inner cam cylinder and a barrier drive ring.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a digital camera which is an example of an embodiment of an imaging apparatus including a lens barrel of the present invention.

  As shown in FIG. 1, the digital camera of this embodiment is provided with a zoom lens barrel 20 on the front side of the camera body 10. In the lens barrel 20, the zoom optical unit 910 (see FIG. 2) changes the shooting magnification by the shooting optical system moving between the shooting position and the retracted position in the optical axis direction.

  Hereinafter, the lens barrel 20 will be described in detail with reference to FIGS. FIG. 2 is an exploded perspective view of the lens barrel 20. FIG. 3 is a cross-sectional view of the lens barrel 20 at the retracted position. FIG. 4 is a cross-sectional view of the lens barrel 20 at the photographing position. FIG. 5 is an exploded perspective view of the first lens unit 100. FIG. 6 is an exploded perspective view of the fifth lens unit 500.

  2 to 4, the lens barrel 20 includes first to fifth lens units 100 to 500 constituting an imaging optical system, an inner cam barrel 601, a first rectilinear barrel 602, an outer cam barrel 701, and a rotation. A cylinder 801, a fixed cylinder 802, and a sensor holder 901 are provided.

  As shown in FIGS. 2 to 5, the first lens unit 100 includes a first group lens frame 120 that holds the first group lens 101, a first group barrel 110, a plurality of barrier blades 102 to 105, a first group cap 106, and a coil. A spring 107 and a barrier drive ring 108 are provided. As shown in FIG. 5, in the inner periphery of the first group barrel 110, a straight groove 110 b that engages with the straight key 602 a of the first straight cylinder 602 and a follower that engages with the cam groove 601 c of the inner cam cylinder 601. 110a is provided.

  The second lens unit 200 includes a second group lens frame 202 that holds the second group lens 201 and the like. As shown in FIG. 2, a follower 202a that engages with the cam groove 601d of the inner cam cylinder 601 and a rectilinear key 202b that engages with the rectilinear groove 602b of the first rectilinear cylinder 602 are disposed on the outer periphery of the second group lens frame 202. Are provided.

  The third lens unit 300 includes third group lens frames 310 and 311 that hold the third group lenses 301a and 301b, a third group base 302, a camera shake correction mechanism, and a shutter / aperture unit 320. The third group base 302 is provided with a rectilinear key 302b that engages with the rectilinear groove 602c of the first rectilinear cylinder 602 and a follower 302a that engages with the cam groove 701e of the outer cam cylinder 701. The third group lens frames 310 and 311 are arranged so as to sandwich the shutter / aperture unit 320 in the optical axis direction, and the third group lens frame 310 holds a pair of IS magnets.

  A pair of IS coils is fixed to the third group base 302 at a position facing the IS magnet. The third group base 302 holds the third group lens frame 310 movably in a plane orthogonal to the optical axis via a plurality of balls 340 in a state where the third group lens frame 310 is biased in the optical axis direction by a spring. On the subject side of the IS magnet, a pair of Hall elements held by the FPC 330 is arranged to face the IS magnet, and the FPC 330 is held by the sensor holder 350. The third group lens frames 310 and 311 are moved in a plane perpendicular to the optical axis by the Lorentz force acting between the IS magnet through the FPC 330 and the IS coil is energized. Camera shake correction is performed by position control based on this.

  The fourth lens unit 400 includes a fourth group lens frame 402 that holds the fourth group lens 401 and the like. A follower 402 a that engages with the cam groove 701 d of the outer cam cylinder 701 and a rectilinear key 402 b that engages with the rectilinear groove 702 d of the second rectilinear cylinder 702 are provided on the outer periphery of the fourth group lens frame 402.

  As shown in FIG. 6, the fifth lens unit 500 includes a fifth group lens frame 502 that holds the fifth group lens 501, an AF base 504, a main guide shaft 511, a focus motor 512, an FPC 513, and a fifth group base 510. The AF base 504 holds a rack 507 and a rack spring 508, and holds the fifth group lens frame 502 so as to be rotatable in a plane direction orthogonal to the optical axis. The AF cover 505 is assembled to the AF base 504 in a state where the fifth group lens frame 502 is urged in the optical axis direction by the AF spring 506. The AF base 504 is restricted in rotation by the main guide shaft 511 and the sub guide shaft 510 c provided on the fifth group base 510.

  A main guide shaft 511 is press-fitted into the fifth group base 510, and a focus motor 512 to which an FPC 513 is connected is fixed by a screw 514 and a nut 515. A screw shaft 512 a is fixed to the output shaft of the focus motor 512. The fifth group base 510 is provided with a follower 510a that engages with a cam groove 801c (see FIG. 2) of the rotating cylinder 801 and a rectilinear key 510b that engages with a rectilinear groove 802d (see FIG. 2) of the fixed cylinder 802. It has been. When the focus motor 512 is driven, the AF base 504 advances and retreats to an arbitrary position in the optical axis direction by the feeding action of the screw shaft 512a and the rack 507, thereby enabling focus adjustment.

  2 to 4, the first rectilinear cylinder 602 is rotatably held by the bayonet coupling on the inner peripheral portion of the inner cam cylinder 601. Further, a cam groove 601 d that engages with the follower 202 a of the second group lens frame 202 is provided in the inner peripheral portion of the inner cam cylinder 601. On the outer peripheral portion of the inner cam cylinder 601, a follower 601 a that engages with a cam groove 702 c of the second rectilinear cylinder 702, an engagement convex part 601 b that engages with an engagement part 603 a of the inner cam cover 603, and an outer cam cylinder 701. A rectilinear key 601e that engages with the rectilinear groove 701e is provided. A cam groove 601 c that engages with the follower 110 a of the first group barrel 110 is provided on the outer peripheral portion of the inner cam barrel 601. The inner cam cover 603 is assembled to the inner cam cylinder 601 in a state where the engaging protrusion 601b of the inner cam cylinder 601 is engaged with the engaging portion 603a.

  A rectilinear key 602 a that engages with a rectilinear groove (not shown) provided on the inner peripheral side of the first group barrel 110 is provided on the outer peripheral portion of the first rectilinear barrel 602. The first rectilinear cylinder 602 is provided with a rectilinear groove 602b that engages with the rectilinear key 202b of the second group lens frame 202 and a rectilinear groove 602c that engages with the rectilinear key 302b of the third group base 302.

  In the inner peripheral portion of the outer cam cylinder 701, a cam groove 701f with which the follower 702a of the second rectilinear cylinder 702 is engaged, a cam groove 701c with which the follower 302a of the third group base 302 is engaged, and a follower of the fourth group lens frame 402 are provided. A cam groove 701d with which 402a is engaged is provided. In addition, a rectilinear groove 701e that engages with the rectilinear key 601e of the inner cam cylinder 601 is provided in the inner peripheral portion of the outer cam cylinder 701. A follower 701 a that engages with the cam groove 802 b of the fixed cylinder 802 and a rectilinear key 701 b that engages with the rectilinear groove 801 a of the rotating cylinder 801 are provided on the outer peripheral portion of the outer cam cylinder 701.

  On the outer periphery of the second rectilinear cylinder 702, a rectilinear key 702b that engages with the rectilinear groove 802c of the fixed cylinder 802 and a follower 702a that engages with the cam groove 701f of the outer cam cylinder 701 are provided. A rectilinear groove 702d in which the rectilinear key 402b of the fourth group lens frame 402 engages and a cam groove 702c in which the follower 601a of the inner cam cylinder 601 engages are provided in the inner peripheral portion of the second rectilinear cylinder 702.

  A follower 802 a that engages with the cam groove 801 b of the rotating cylinder 801 is provided on the outer peripheral portion of the fixed cylinder 802. In the inner peripheral portion of the fixed cylinder 802, a rectilinear groove 802d in which the rectilinear key 501b of the fifth group base 510 is engaged, a rectilinear groove 802c in which the rectilinear key 702b of the second rectilinear cylinder 702 is engaged, and an outer cam cylinder 701 A cam groove 802b with which the follower 701a is engaged is provided.

  A gear portion 801 d to which the zoom driving unit 910 is coupled is provided on the outer peripheral portion of the rotating cylinder 801. A cam groove 801b with which the follower 802a of the fixed cylinder 802 engages, a rectilinear groove 801a with which the rectilinear key 701b of the outer cam cylinder 701 engages, and a follower 510a of the fifth group base 510 are engaged with the inner peripheral portion of the rotating cylinder 801. A mating cam groove 801c is provided. A cover cylinder 803 is disposed on the outer peripheral side of the rotary cylinder 801, and the cover cylinder 803 is fixed to the sensor holder 901. The sensor holder 901 holds the zoom drive unit 910, the optical element 902, the sensor rubber 903, and the image sensor 900.

  Next, the zoom operation of the lens barrel 20 will be briefly described. When the rotary cylinder 801 is rotationally driven by the zoom drive unit 910, the outer cam cylinder 701 moves in the optical axis direction while rotating by the cam action of the rotary cylinder 801 and the fixed cylinder 802. The inner cam cylinder 601 is rotatably held by the first rectilinear cylinder 602, and the outer cam cylinder 701 is rotatably held by the second rectilinear cylinder 702.

  When the outer cam cylinder 701 is rotationally driven, the inner cam cylinder 601 is rotationally driven by the outer cam cylinder 701, and the first rectilinear cylinder 602 and the second rectilinear cylinder 702 are fixed cylinder 802 via the third group base 302. Is restricted by the rotation. Thereby, the outer cam cylinder 701 and the inner cam cylinder 601 move in the optical axis direction while rotating.

  The first lens unit 100 and the second lens unit 200 are restricted in rotation by the first rectilinear cylinder 602, and move straight in the optical axis direction when the inner cam cylinder 601 rotates. The third lens unit 300 and the fourth lens unit 400 are restricted in rotation by the second rectilinear cylinder 702, and move linearly in the optical axis direction when the outer cam cylinder 701 rotates. The fifth lens unit 500 is linearly moved in the optical axis direction when the fifth group base 510 is restricted in rotation by the fixed cylinder 802 and the rotary cylinder 801 rotates.

  The AF base 504 is restricted in rotation by the main guide shaft 511 and the sub-guide shaft 510 c, and is optically held in the fifth group base 502 by the action of the screw shaft 512 a provided on the output shaft of the focus motor 512 and the rack 507. Move straight in the axial direction.

  As described above, the lens barrel 20 is driven by the zoom driving unit 910 to rotate the rotary cylinder 801, so that each lens group is extended, and the focus motor 512 is driven to thereby change the fifth group lens 501. It is extended to an arbitrary position and moved from the retracted position to the shooting position.

  Next, the barrier mechanism provided in the first lens unit 100 will be described in detail with reference to FIGS. 5 and 7 to 17.

  As shown in FIG. 5, the barrier mechanism includes a first group cap 106, a plurality of barrier blades 102 to 105, a barrier drive ring 108, a coil spring 107, and a first group barrel 110. The plurality of barrier blades 102 to 105 each form a pair. The pair of barrier blades 102 to 105 are rotatable in opposite directions to cover the opening 106a of the first group cap 106 from which the first group lens 101 is exposed. Here, the barrier blade 105 corresponds to an example of the subject-side barrier blade of the present invention that is closest to the subject among the plurality of barrier blades, and the first group barrel 110 corresponds to an example of the barrier tube of the present invention.

  The barrier blades 102 are formed of a resin material, and the barrier blades 103 to 105 are formed of a metal material. The barrier blades 102 to 105 are arranged in the open state so as to overlap each other in the optical axis direction. The barrier drive ring 108 and the first group barrel 110 are each formed of a resin material, and the first group cap 106 is fixed to the first group barrel 110 by a double-sided tape 109.

  FIG. 7 is a view of the barrier mechanism in which the pair of barrier blades 102 to 105 are closed as viewed from the subject side. FIG. 8 is a view of the barrier mechanism in which the pair of barrier blades 102 to 105 are open as viewed from the subject side. FIG. 9 is a view of the barrier mechanism with the pair of barrier blades 102 to 105 closed, as viewed from the image plane side. FIG. 10 is a view of the barrier mechanism in which the pair of barrier blades 102 to 105 are open as viewed from the image plane side.

  FIG. 11 shows a state in which some of the barrier blades 103 to 105 are removed from one of the barrier blades 102 to 105 of the pair of barrier blades 102 to 105 in the barrier mechanism in which the pair of barrier blades 102 to 105 are closed. FIG. FIG. 12 is a view of the barrier mechanism in which the pair of barrier blades 102 to 105 are open as viewed from the subject side with the first group cap 106 removed.

  FIG. 13 is a perspective view showing a closed state of one barrier blade 102 to 105 of the pair of barrier blades 102 to 105. FIG. 14 is a perspective view showing the relationship between the barrier blade 102 and the barrier blade 103 in the open state. FIG. 15 is a side view of the barrier mechanism in which the pair of barrier blades 102 to 105 are closed. FIG. 16 is a cross-sectional view of a main part for explaining the relationship between the rail portion 108 h of the barrier drive ring 108 and the rail portion 110 g of the first group barrel 110. FIG. 17 is a cross-sectional view showing the relationship between the inner cam cylinder 601 and the barrier drive ring 108.

  As shown in FIG. 11, the barrier drive ring 108 is provided with two flange portions 108 c protruding outward in the radial direction and spaced apart by 180 ° in the circumferential direction. Further, the barrier drive ring 108 is provided with two flange portions 108d protruding outward in the radial direction with a phase difference of 90 ° with respect to the flange portion 108c and spaced 180 ° in the circumferential direction. Further, the barrier drive ring 108 is provided with two flange portions 108e protruding outward in the radial direction, located between the flange portions 108c and 108d and spaced apart by 180 ° in the circumferential direction.

  The first group barrel 110 is provided with bayonet claw portions 110c, 110d, and 110e at positions corresponding to the flange portions 108c, 108d, and 108e of the barrier drive ring 108, respectively. By subjecting the flange portions 108c, 108d, and 108e of the barrier drive ring 108 to the bayonet claw portions 110c, 110d, and 110e of the first group barrel 110, the subject with respect to the first group barrel 110 in the optical axis direction of the barrier drive ring 108 is obtained. The position of the side is determined.

  As shown in FIG. 16, the rail portion 110g of the first lens barrel 110 is connected to the optical axis on the rail portion 108h of the barrier drive ring 108 with respect to the image side surface (lower surface in the drawing) of the barrier drive ring 108. Abut in the direction. Thereby, the position of the barrier drive ring 108 on the image plane side with respect to the first group barrel 110 in the optical axis direction is determined.

  As shown in FIGS. 16 and 17, the barrier drive ring 108 is formed with three protrusions 108j protruding toward the image plane side at substantially equal intervals in the circumferential direction. The protrusion 108j is inserted in a radial direction into an arc groove 110h formed in the first group barrel 110 corresponding to the protrusion 108j, and comes into contact with the inner peripheral surface of the arc groove 110h. Accordingly, the barrier drive ring 108 is rotatably held with respect to the first group barrel 110.

  As shown in FIGS. 7 and 8, the first group cap 106 has an opening 106 a corresponding to an effective aperture area (area where a light beam effective for imaging is incident) on the subject side of the first group lens 101. As described above, the opening 106a is closed when the barrier blades 102 to 105 are closed, and is opened when the barrier blades 102 to 105 are open. By closing the opening 106a with the barrier blades 102 to 105 in the closed state, the subject side of the first group lens 101 is covered and the first group lens 101 is protected. The first group cap 106 is bonded and fixed by a double-sided tape 109 attached to the top surface of the first group barrel 110.

  As shown in FIGS. 8, 10, and 12, when the barrier blades 102 to 105 are in the open state, the barrier blades 102 to 105 are housed in positions that overlap each other in the optical axis direction. A shaft 102a (see FIG. 10) is provided on the image plane side of the base of the barrier blade 102 made of a resin material, and a shaft 102b (see FIG. 12) is provided on the subject side. As shown in FIG. 12, the shaft 102a and the shaft 102b are arranged not in the same axis but in parallel. The shaft 102 a on the image plane side of the barrier blade 102 is inserted into a hole (not shown) formed in the first group barrel 110, and the shaft 102 b on the subject side is inserted into a hole 103 a (see FIG. 5).

  Similarly, the subject-side shaft 102b of the barrier blade 102 is sequentially inserted into the hole 104a formed in the barrier blade 104 and the hole 105a formed in the barrier blade 105. Thereby, the barrier blades 102 are supported so as to be rotatable in the opening / closing direction (the direction of arrow B or E in FIG. 11) about the shaft 102a, and the barrier blades 103 to 105 are opened / closed about the shaft 102b ( It is supported rotatably in the direction of arrow C or F in FIG.

  Here, as described above, since the image plane side shaft 102a and the subject side shaft 102b of the barrier blade 102 are arranged in parallel, the barrier blade 102 is rotated around the shaft 102a. The shaft 102b that is the rotation center of the barrier blades 103 to 105 moves.

  As shown in FIGS. 9, 11, and 13, a distal end side stepped recess 102 k and a proximal end stepped recess 102 j are formed at the distal end and the proximal end of the pair of barrier blades 102, respectively. The front end side step concave portion 102k of the barrier blade 102 is formed so as to face the subject side, and the base end side step concave portion 102j is formed so as to face the image surface side.

  In the closed state of the pair of barrier blades 102, the tip side stepped recess 102k of one (other) barrier blade 102 is inserted into the base end stepped recess 102j of the other (one) barrier blade 102 in the rotational direction. . At this time, the front end side step concave portion 102k and the base end side step concave portion 102j are arranged to face each other in the optical axis direction, and the surfaces of the pair of barrier blades 102 are arranged on the same plane.

  As shown in FIG. 11, a guiding portion 102 m is formed by chamfering or the like on the inner peripheral side in the opening / closing direction of the base end portion of the barrier blade 102. Further, at the tip of the barrier blade 103 facing the opening / closing direction of the barrier blade 102, a riding-up portion 103e that rides on the barrier blade 102 via the guide portion 102m in the closed state of the barrier blades 102, 103 is formed.

  The ride-up unit 103e rides on the surface of the barrier blade 102 on the subject side so as to overlap in the optical axis direction. As a result, even when the height between the pair of barrier blades 102 is shifted in the optical axis direction due to rattling or the like, the climbing portion 103e of the barrier blade 103 rides on the subject side surface of the barrier blade 102, thereby The heights of the blades 102 in the optical axis direction can be made uniform.

  As shown in FIG. 13, a bent portion 104c bent toward the image plane side is formed on the outer peripheral side of the barrier blade 104 in the opening and closing direction. Further, on the outer peripheral side in the opening and closing direction of the barrier blade 105, a bent portion 105c and two bent portions 105f bent to the image surface side opposite to the subject side are formed. Protrusions 105d and 105e projecting toward the opening direction of the barrier blade 105 are formed at the ends of the bent parts 105c and 105f, respectively. The protrusions 105d and 105e correspond to an example of the first protrusion of the present invention.

  As shown in FIG. 15, a lateral hole portion 110 f is formed in the inner peripheral portion of the first group barrel 110. The protrusion 105e of the barrier blade 105 is inserted into the horizontal hole portion 110f so as to overlap in the optical axis direction when the barrier blade is open.

  As shown in FIGS. 9 and 11, in the closed state of the pair of barrier blades 102, the tip portion of the tip side stepped recess 102 k of one (other) barrier blade 102 is the base of the other (one) barrier blade 102. It is arranged to project from the end side stepped recess 102j to the opposite side. At this time, the tip end portion of the tip side stepped recess 102 k of the barrier blade 102 reaches the end surface on the subject side of the barrier drive ring 108.

  During the rotation from the closed state shown in FIG. 11 to the open state shown in FIG. 12, the front end portion of the front end side step concave portion 102 k moves the end face on the subject side of the barrier drive ring 108. In the closed state of the barrier blade 102, the proximal-side step recess 102j is provided on the image plane side of the barrier blade 102, so that the distal-end step recess 102k is not visible in appearance. In addition, when the tip portion of the tip side stepped recess 102k is subjected to static pressure, it is pressed against the end surface on the subject side of the barrier drive ring 108, so that the tip portion is loaded from the subject side when the barrier blades 102 to 105 are closed. It will be a static pressure receiver.

  In the closed state of the barrier blades 102 to 105, the protrusions 105 d and 105 e of the barrier blade 105 ride on the subject-side end surface of the barrier drive ring 108 and overlap in the optical axis direction. The static pressure is received even if it receives a static pressure from. Further, the tip protrusion 105g provided on the tip side of the protrusions 105d and 105e of the barrier blade 105 is in the optical axis direction with the subject side flat portion 110m of the first lens barrel 110 when the barrier blades 102 to 105 are closed. overlapping. For this reason, a static pressure is received similarly to the protrusions 105d and 105e of the barrier blade 105.

  At this time, the tip protrusion 105g is bent and formed at an angle that is not perpendicular to the barrier blade 105, so that unlike the other protrusions 105d and 105e, a static pressure is not received on a flat surface. . That is, the area where the tip protrusion 105 g contacts the subject side flat part 110 m of the first group barrel 110 is smaller than the area where the protrusions 105 d and 105 e contact the subject side end face of the barrier drive ring 108.

  Thus, when the barrier blades 102 to 105 are opened and closed, even if the tip protruding portion 105g contacts the subject side flat portion 110m of the first lens barrel 110, a large sliding load does not occur, and a contact surface 110n described later due to friction. The barrier blades 102 to 105 are prevented from stopping before coming into contact with each other. The tip protrusion 105g corresponds to an example of a second protrusion of the present invention.

  In addition, the subject-side plane portion 110m of the first group barrel 110 is formed so as to overlap with the tip protrusion portion 105g in the optical axis direction only when the barrier blades 102 to 105 are closed. For this reason, when the barrier blades 102 to 105 are rotated from the closed position toward the open position, the gap between the tip protruding portion 105g and the first group lens barrel 110 in the optical axis direction gradually increases. A dynamic load can be prevented.

  Further, when the front end protruding portion 105g of the barrier blade 105 moves to a position where the front end protruding portion 105g of the barrier blade 105 overlaps with the subject side flat portion 110m of the first group barrel 110 close to the optical axis direction, the front end protruding portion An inclined surface 110r that avoids 105g of interference is formed. The inclined surface 110r is formed to be inclined toward the subject flat surface portion 110m. Thereby, it can prevent that the front-end | tip protrusion part 105g of the barrier blade | wing 105 is caught by the side surface of the to-be-photographed object plane part 110m of the 1st group lens barrel 110. FIG.

  The front end protruding portion 105g of the barrier blade 105 is disposed close to the contact surface 110n of the first lens barrel 110 in the rotation direction at the closed position of the barrier blades 102 to 105, and contacts the contact surface 110n as a stopper portion. By contact, rotation of the barrier blade 105 in the closing direction is restricted. Here, as shown in FIG. 15, the distance G in the optical axis direction between the tip protruding portion 105 g of the barrier blade 105 and the subject-side flat surface portion 110 m of the first group barrel 110 is the protruding portions 105 d and 105 e and the barrier driving ring 108. Is set wider than the distance H in the optical axis direction from the subject-side end surface.

  For this reason, if the subject-side end surface of the barrier drive ring 108 with which the projecting portions 105d and 105e abut is the main static pressure receiver, the subject-side flat surface portion 110m of the first group barrel 110 with which the tip projecting portion 105g abuts is positive. In effect, it functions as a sub static pressure receiver where no static pressure is applied. Accordingly, it is possible to disperse a load that cannot be received only by the main static pressure receiver, and to prevent deformation due to an excessive load applied to the tip protrusion 105g, and to ensure a stable closed state of the barrier blade 105. It becomes possible.

  As shown in FIGS. 13 and 14, the claw portion of the link portion 103 b formed on the barrier blade 103 made of a metal material is detachably hooked on the image plane side of the barrier blade 102 made of a resin material. A latching protrusion 102e is provided. An inclined portion is formed on the surface of the hooking convex portion 102e opposite to the portion where the claw portion of the link portion 103b is hooked, and the inclined portion is re-attached to the claw portion during assembly or when the claw portion is removed. It has a guiding shape for hanging.

  The barrier blade 102 is formed with a groove for allowing the link portion 103b to move between the latching convex portion 102e and the stepped portion 102k, and a through hole 102f is formed in the stepped portion 102k. The barrier blade 102 is formed with a convex portion 102p that comes into contact with the first lens group 101 in the optical axis direction when pressed from outside such as static pressure. Around the convex portion 102p, a concave curved surface portion 102q is formed as a relief shape so as not to hit the first group lens 101 when the barrier blade 102 is closed or in the middle of opening and closing.

  The link portion 103b includes a bent portion 103c1 that is bent 90 ° from the outer peripheral portion of the barrier blade 103 toward the image plane side, and an arm portion 103c2 that is bent 90 ° from the tip of the bent portion 103c1 and extends parallel to the barrier blade 103. . At the tip of the arm portion 103c2 of the barrier blade 103, a claw portion that is hooked on the hooking convex portion 102e of the barrier blade 102 is formed. An outer peripheral portion 102g of the barrier blade 102 is sandwiched between the barrier blade 103 and the arm portion 103c2 of the link portion 103b in the optical axis direction.

  As shown in FIG. 14, the link portion 103b of the barrier blade 103 is disposed in a groove portion from the through hole 102f formed in the barrier blade 102 to the latching convex portion 102e from the open state to the closed state of the barrier blade 103. For this reason, the link portion 103b of the barrier blade 103 does not come out of the concave curved surface portion 102q formed around the convex portion 102p of the barrier blade 102, and is disposed within the width of the barrier blade 102 in the rotation direction. The For this reason, the link part 103b of the barrier blade 103 does not protrude from the barrier blade 102 toward the barrier drive ring 108. The through hole 102f is formed at a position that cannot be seen from the subject side when the barrier blade 102 is closed.

  As shown in FIGS. 9 and 11, the coil spring 107 is formed of a tension spring and has hook portions that are oriented at 90 ° to each other at both ends thereof. One hook portion of the coil spring 107 is hooked on the hook portion 102d of the barrier blade 102, and the other hook portion is hooked on the hook portion 108g of the barrier drive ring 108.

  When the coil spring 107 is charged, the coil spring 107 generates an urging force so as to draw the barrier blade 102 and the barrier drive ring 108 toward each other. That is, the charged coil spring 107 urges the barrier blade 102 in the direction of arrow B in FIG. 11 (the direction of rotation from the open position to the closed position), and the barrier drive ring 108 in the direction of arrow D (from the closed position). Energize in the direction of rotation to the open position).

  As shown in FIG. 16, the barrier drive ring 108 is provided with an interlocking lever 108f extending to the image plane side, and the interlocking lever 108f passes through the hole 110k of the first group barrel 110 as shown in FIG. . When the lens barrel 20 is retracted (when the barrier blades 102 to 105 are closed), the interlocking lever 108f is engaged with a lever drive groove 601f formed in the inner cam barrel 601 as shown in FIG. .

  As shown in FIG. 14, when the barrier blade 102 rotates in the direction of arrow E (from the closed position to the open position), the outer peripheral portion 102 g of the barrier blade 102 is in contact with the bent portion 103 c 1 of the link portion 103 b of the barrier blade 103. Abut. When the barrier blade 102 rotates in the direction of arrow B (from the open position to the closed position), as shown in FIG. 13, the arm of the link portion 103b of the barrier blade 103 is engaged with the latching convex portion 102e of the barrier blade 102. The claw portion at the tip of the portion 103c2 is hooked. As a result, the barrier blade 102 and the barrier blade 103 are connected, and the barrier blade 103 rotates in conjunction with the rotation operation of the barrier blade 102.

  Similarly, the front end portion 103 d of the barrier blade 103 is hooked on the claw portion 104 b at the front end portion of the barrier blade 104. As a result, the barrier blade 104 rotates in conjunction with the rotation operation of the barrier blade 103.

  Further, the front end portion 104 e of the barrier blade 104 is hooked on the claw portion 105 b at the front end portion of the barrier blade 105. As a result, the barrier blade 105 rotates in conjunction with the rotation operation of the barrier blade 104. The link portion 103b, the claw portion 104b, and the claw portion 105b are disposed at positions that do not interfere with each other when the barrier blades 102 to 105 are rotated in the opening / closing direction.

  Next, the operation from the open state to the closed state of the barrier blades 102 to 105 in the barrier mechanism will be described. In addition, since the opening / closing operation | movement of a pair of barrier blades 102-105 is the same, only the operation | movement from the open state of one barrier blade 102-105 to a closed state is demonstrated here.

  As shown in FIG. 17, the inner cam cylinder 601 has a lever drive groove 601f at a position corresponding to the interlocking lever 108f of the barrier drive ring 108. The lever driving groove 601f pushes the interlocking lever 108f to rotate the barrier driving ring 108 as the inner cam cylinder 601 rotates due to the retracting operation of the lens barrel 20.

  The barrier drive ring 108 rotates in the direction of arrow A in FIG. 11 when the interlocking lever 108f is pushed by the lever drive groove 601f of the inner cam cylinder 601 from the opened state of the barrier blades 102 to 105 shown in FIG. When the barrier drive ring 108 rotates in the direction of arrow A, the coil spring 107 is charged, and the barrier blade 102 is pulled by the urging force of the coil spring 107 and rotates in the direction of arrow B about the shaft 102a. As described above, the barrier drive ring 108 rotates the barrier blade 102 toward the closed position via the coil spring 107.

  The barrier blade 103 overlaps the barrier blade 102, and when the friction force between the barrier blades 102, 103 is high, the barrier blade 103 starts to rotate in the direction of arrow B integrally with the barrier blade 102 by the friction force. When the frictional force between the barrier blades 102 and 103 is low, the barrier blade 103 does not follow the rotation of the barrier blade 102, so the relative rotation direction of the barrier blade 103 with respect to the barrier blade 102 is opposite to the arrow B. Direction arrow C direction. In addition to the frictional force, depending on the posture difference, the direction of gravity applied to each barrier blade changes, which rotation direction changes.

  Therefore, when the rotation angle in the arrow B direction around the axis 102a of the barrier blade 102 is B1, and the relative rotation angle in the arrow C direction around the shaft 102b of the barrier blade 103 is C2, the barrier The shaft 102b of the blade 102 rotates about the shaft 102a by an angle C2. That is, the angle of rotation of the barrier blade 103 in a trajectory that revolves around the axis 102a of the barrier blade 102 in the direction of arrow B is reduced to B1-C2, and as a result, the angle indicated by B1-C2 in FIG. Move.

  Similarly, the barrier blade 104 overlapping the barrier blade 103 is also rotated at an angle indicated by B1-C3, where C3 is a relative rotation angle in the arrow C direction with respect to the barrier blade 102. Similarly, the barrier blade 105 overlapping the barrier blade 104 is also rotated at an angle indicated by B1-C4, where C4 is a relative rotation angle in the direction of arrow C with respect to the barrier blade 102.

  As shown in FIG. 13, when the latching convex portion 102e of the barrier blade 102 is hooked on the claw portion of the link portion 103b of the barrier blade 103, the rotation of the barrier blade 103 around the shaft 102b in the direction of arrow C in FIG. Disappear. Then, the barrier blade 103 starts to rotate in the arrow B direction in conjunction with the rotation operation of the barrier blade 102. Thereafter, the front end portion 103 d of the barrier blade 103 is hooked on the claw portion 104 b of the barrier blade 104, so that the barrier blade 104 rotates in conjunction with the barrier blades 102 and 103. Further, when the tip 104 e of the barrier blade 104 is caught by the claw portion 105 b of the barrier blade 105, the barrier blade 105 rotates in conjunction with the barrier blades 102 to 104.

  Further, the barrier blade 102 comes into contact with the other barrier blade 102 and stops. At this time, the barrier blades 103 to 105 are integrally rotated in the direction of the arrow B in FIG. 11, and as described above, the barrier blade 105 is such that the tip of the protruding portion 105 g contacts the first group barrel 110. Stops against the surface 110n. Thereby, the barrier blades 102 to 105 are closed, the opening 106a of the first group cap 106 is closed, the subject side of the first group lens 101 is covered, and the first group lens 101 is protected.

  Next, the operation from the closed state to the open state of the barrier blades 102 to 105 in the barrier mechanism will be described. In addition, since the opening / closing operation | movement of a pair of barrier blades 102-105 is the same, only the operation | movement from the closed state of one barrier blade 102-105 to an open state is demonstrated here.

  In the closed state of the barrier blades 102 to 105 shown in FIG. 11, when the inner cam cylinder 601 is rotated in response to the extending operation of the lens barrel 20 from the retracted state, the interlock lever 108f is pushed by the lever driving groove 601f. Canceled. As a result, the barrier drive ring 108 rotates in the direction of arrow D in FIG. 11 by the biasing force of the coil spring 107 that has been charged.

  When the barrier drive ring 108 rotates in the direction of arrow D, the wall portion 108b formed on the barrier drive ring 108 pushes the protrusion 102c of the barrier blade 102. Thereby, the barrier blade 102 receives the driving force in the direction of arrow E around the shaft 102a and starts to rotate in the opening direction.

  At this time, the barrier blades 103, 104, and 105 are fitted to the shaft 102b. For this reason, the shaft 102b moves by rotating about the shaft 102a. However, before it comes into contact with the abutting portion of the barrier blade 102 corresponding to the barrier blades 103, 104, 105, the shaft 102b is relatively centered on the shaft 102b by inertial force. To the arrow F direction opposite to the arrow E direction.

  Then, as shown in FIG. 14, the barrier blade 102 continues to rotate in the direction of arrow E, and the outer peripheral portion 102 g of the barrier blade 102 contacts the bent portion 103 c 1 of the barrier blade 103. After the contact, the barrier blade 103 starts to rotate together with the barrier blade 102 in the direction of arrow E around the shaft 102a.

  Thereafter, when the barrier blade 103 rotates together with the barrier blade 102 in the direction of arrow E, the outer peripheral portion 102h of the barrier blade 102 abuts against the bent portion 104c of the barrier blade 104 as shown in FIG. When the barrier blade 104 further rotates together with the barrier blades 102 and 103 in the direction of arrow E, the outer peripheral portion 102 i of the barrier blade 102 abuts against the bent portion 105 c of the barrier blade 105.

  Thereafter, as shown in FIG. 12, the tip 102n of the barrier blade 102 abuts against the stopper 110j of the first group barrel 110 and stops. Thereby, the barrier blades 102 to 105 are accommodated in the open position, the opening 106a of the first group cap 106 is opened, and the open state shown in FIG. 8 is maintained. At this time, the barrier blades 102 to 105 are arranged at positions overlapping each other in the optical axis direction.

  As described above, in this embodiment, when a load is applied from the subject side with the barrier blades 102 to 105 closed, the protrusions 105d and 105e of the barrier blade 105 closest to the subject are on the subject side of the barrier drive ring 108. Abuts against the end face and functions as a main static pressure receiver. Further, when a larger load is applied from the subject side in the closed state of the barrier blades 102 to 105, the tip protruding portion 105 g of the barrier blade 105 abuts on the subject-side flat portion 110 m of the first group barrel 110 and the sub static Functions as a pressure bearing. Thereby, the load received from the subject side in the closed state of the barrier blades 102 to 105 can be received in a balanced manner without causing an increase in the size of the barrier drive ring 108 and the lens barrel.

  The configuration of the present invention is not limited to that exemplified in the above embodiment, and the material, shape, dimensions, form, number, arrangement location, and the like can be changed as appropriate without departing from the scope of the present invention. It is.

  For example, in the above-described embodiment, the barrier mechanism used for the digital still camera is exemplified, but the present invention is not limited to this, and a silver salt camera, a digital video camera, a portable terminal with a camera function, other imaging devices, devices including the imaging devices, etc. The present invention may be applied to a barrier mechanism used in the above.

20 Lens barrel 101 First lens group 102-105 Barrier blades 105d, 105e Projection 105g Tip projection 106a Opening 108 Barrier drive ring 110 First lens barrel

Claims (7)

A plurality of barrier blades rotatably provided in a direction to open and close the lens exposed to the subject side through the opening;
A barrier driving ring for driving the plurality of barrier blades in the opening and closing direction;
A barrier cylinder that rotatably holds the barrier driving ring and supports the plurality of barrier blades so as to be rotatable in the opening and closing direction;
Among the plurality of barrier blades, on the outer peripheral side in the opening and closing direction of the subject side barrier blade closest to the subject side, a first protruding portion that protrudes opposite to the subject side, and the first protruding portion A second protrusion disposed on the tip side of the subject-side barrier blade is provided;
The first protrusion comes into contact with an end surface on the subject side of the barrier driving ring when a load from the optical axis direction is applied to the subject side barrier blade in the closed state of the subject side barrier blade. Are arranged in the direction of the optical axis,
The second projecting portion comes into contact with the subject-side end surface of the barrier cylinder when a load from the optical axis direction is applied to the subject-side barrier blade in the closed state of the subject-side barrier blade. A lens barrel characterized by being arranged so as to overlap in the optical axis direction. The barrier cylinder is provided with a stopper portion that restricts rotation of the subject side barrier blade in the closing direction when the subject side barrier blade is closed,
2. The lens mirror according to claim 1, wherein the second projecting portion is disposed close to the stopper portion in the rotation direction of the barrier cylinder in a closed state of the subject-side barrier blade. Tube.   The distance in the optical axis direction between the second projecting portion and the subject-side end surface of the barrier cylinder when the subject-side barrier blade is in the closed state is the subject side of the first projecting portion and the barrier driving ring. 3. The lens barrel according to claim 1, wherein the lens barrel is set wider than an interval in the optical axis direction with respect to the end surface of the lens barrel.   The said 2nd protrusion part is formed in the shape which does not make a flat contact in the optical axis direction with respect to the to-be-photographed object side end surface of the said barrier cylinder, The Claim 1 thru | or 3 characterized by the above-mentioned. Lens barrel.   The distance between the second protrusion and the barrier tube in the optical axis direction is wider in the open state of the subject-side barrier blade than in the closed state of the subject-side barrier blade. The lens barrel according to any one of the above.   When the second protrusion of the subject-side barrier blade moves to a position overlapping the subject-side end surface of the barrier cylinder in the optical axis direction, the barrier cylinder interferes with the second protrusion. The lens barrel according to any one of claims 1 to 5, wherein an inclined surface that avoids the above is formed.   An imaging apparatus comprising the lens barrel according to any one of claims 1 to 6.