JP5215235B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel having a configuration in which different members are fixed in an optical axis direction.

  Some lens barrels that hold optical members such as lenses are provided with a fixed diaphragm having an opening with a predetermined diameter, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2008-46501.

  Since the fixed diaphragm requires a predetermined accuracy for the shape and positioning of the opening, the fixed diaphragm is formed separately from the frame member constituting the lens barrel and then fixed to the frame member with an adhesive. In addition, an adhesive is also used when the frame members formed separately are fixed to each other.

JP 2008-46501 A

  However, when another member such as a fixed diaphragm or a frame member is positioned and fixed to the frame member with an adhesive, a waiting time is required until the adhesive is cured. Such a waiting time causes an increase in the cost of manufacturing the product, and also causes a defect that the position of the member is shifted before the curing, and it cannot be fixed with a desired positioning accuracy.

  The present invention has been made in view of the above problems, and in the case of fixing members constituting a lens barrel, the members can be quickly positioned with a predetermined accuracy and fixed without failure. The purpose is to provide a configuration.

  A lens barrel according to the present invention includes a holding frame portion that holds a lens, and an opening portion that is disposed in one of the holding frame portions in the optical axis direction of the lens and through which the optical axis of the lens passes. 1. A lens barrel comprising: a first member; and a second member that holds the holding frame portion and positions and holds the first member with respect to the holding frame portion. Around the opening of the member, a plurality of engagement claw portions arranged in the circumferential direction of the optical axis and extending toward the second member, and around the holding frame portion of the second member, A plurality of first engagement holes disposed at positions corresponding to the plurality of engagement claws, and engaged with the plurality of engagement claws inserted, and the first engagement holes The first member is connected to one side in the circumferential direction of the optical axis, is narrower in the radial direction than the first engagement hole, and the first member is the second member. On the other hand, when it is rotated to one side in the circumferential direction of the optical axis, it engages with the plurality of engaging claws inserted, and the engaging claw is predetermined in the radial direction of the optical axis. A plurality of second engagement holes sandwiched by fitting, a first cylindrical portion projecting from the first member around the optical axis toward the second member, and the second member Projecting from the first member to the first member side and fitting to the first cylindrical portion, and the second member from the first member around the optical axis. A rotation stop boss projecting to the member side, and the rotation stop boss provided in the second member, wherein the plurality of engagement claw portions engage with the plurality of second engagement holes. And a boss insertion hole for restricting rotation of the first member around the optical axis with respect to the second member. The features.

  ADVANTAGE OF THE INVENTION According to this invention, when adhering the members which comprise a lens-barrel, the structure which can position members with a predetermined precision quickly and can adhere without failure can be provided.

It is a longitudinal cross-sectional view including the lens optical axis in the retracted state of the lens barrel. It is a longitudinal cross-sectional view containing the lens optical axis in the wide state which can image | photograph a lens barrel. It is a longitudinal sectional view including the lens optical axis in the tele state where the lens barrel can be photographed. It is a disassembled perspective view which shows a part of lens barrel. FIG. 5 is an exploded perspective view showing another part of the lens barrel in FIG. 4. FIG. 3 is an exploded perspective view of a third group frame and a shutter / aperture unit in a lens barrel. It is a front view of an imaging unit. It is a front view of a 3 group frame. It is a rear view of a fixed aperture. It is XX sectional drawing of FIG. It is sectional drawing of the state which fixed the fixed aperture_diaphragm | restriction to the 3 group frame. It is a figure for demonstrating the relationship between a 1st engagement hole part and an engagement nail | claw part. It is a figure for demonstrating the relationship between a 2nd engagement hole part and an engagement nail | claw part.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In each drawing used for the following description, the scale is different for each component in order to make each component large enough to be recognized on the drawing. It is not limited only to the quantity of the component described in the figure, the shape of the component, the ratio of the size of the component, and the relative positional relationship of each component.

  As shown in FIGS. 1 to 3, the lens barrel 1 of the present embodiment includes a first group lens 21 having positive refractive power, a second group lens 22 having negative refractive power, a third group lens 23 having positive refractive power, and A lens barrel capable of collapsible holding a photographic optical system having a four-group configuration composed of a four-group lens 24 having a positive refractive power, in which a frame member holding the photographic optical system is retracted in a non-photographing state. . The lens barrel 1 incorporates a shutter / aperture unit 8.

  In the present embodiment, as an example, the lens barrel 1 is configured integrally with an imaging unit 90 that holds the imaging element 96 on the imaging surface of the imaging optical system. The imaging unit 90 has a so-called image blur correction mechanism that supports the imaging element 96 so as to be movable on a plane orthogonal to the optical axis of the imaging optical system.

  In the following description, the photographing lens optical axis of the photographing optical system is indicated by “O”. Of the directions along the optical axis O (hereinafter referred to as the optical axis O direction), the subject side direction is defined as the front, and the imaging side direction is defined as the rear. Further, it is a direction orthogonal to the optical axis O, and when viewed from the front side, the left-right direction is the X direction, and particularly the right direction is the + X side. It is a direction orthogonal to the optical axis O, and the vertical direction is the Y direction, and the upward direction is the + Y side. A plane orthogonal to the optical axis O is defined as an XY plane.

  Although described in detail later, the lens barrel 1 is a frame member that holds and moves the first group lens 21, the second group lens 22, the third group lens 23, and the fourth group lens 24, respectively. A frame 6, a third group frame 7, and a fourth group frame 12 are provided. The first group frame 4, the second group frame 6, the third group frame 7, and the fourth group frame 12 are movable relative to the fixed frame 13 in the optical axis O direction.

  When the lens barrel 1 is in the retracted state, as shown in FIG. 1, the frame member is retracted to the fixed frame 13 side, which will be described later, and the first group lens 21, the second group lens 22, the third group lens 23, and the fourth group lens. 24 approaches each other, and the total length in the optical axis O direction is shortened. On the other hand, when the lens barrel 1 is in a zoom wide state and a zoom telephoto state where photographing is possible, the frame member is extended forward from the fixed frame 13 in the optical axis O direction as shown in FIGS.

  Hereinafter, the configuration of the lens barrel 1 will be described. 4 and 5, the lens barrel 1 includes a barrier device 3, a first group frame 4, a second group frame 6, a cam frame 5, a third group frame 7, a shutter / aperture unit 8, a float key 9, and a movement The frame 10, the rotation frame 11, the fourth group frame 12, the fixed frame 13, the zoom drive unit 50, the focus drive unit 60, and the imaging unit 90 are mainly configured.

  The barrier device 3 is disposed on the front side of the photographing optical system, and protects the photographing optical system by opening and closing an opening provided on the optical path of the photographing optical system with a movable shielding member. The cam frame 5 is used to drive the first group frame 4 and the second group frame 6 forward and backward in the direction of the optical axis O by rotating around the optical axis O. The float key 9 is for restricting the rotation of the first group frame 4 and the second group frame 6 around the optical axis O. The moving frame 10 is used to drive the cam frame 5 back and forth in the direction of the optical axis O and to restrict the rotation of the third group frame 7 and the float key 9 around the optical axis O. The rotating frame 11 is for rotating the cam frame 5 by rotating around the optical axis O and moving the third group frame 7 forward and backward in the optical axis O direction.

  The fixed frame 13 is a member whose position is fixed with respect to the optical axis O, supports the rotary frame 11 so as to be capable of rotating and moving back and forth around the optical axis O, and further around the optical axis O of the movable frame 10. It is for restricting rotation. The zoom drive unit 50 is for rotating the rotary frame 11 around the optical axis O. The focus drive unit 60 is for driving the fourth group frame 12 forward and backward in the optical axis O direction. The image pickup unit 90 is for holding the image pickup device 96 and driving the image pickup device 96 to be displaced on a plane orthogonal to the optical axis O.

  Below, the detailed structure of each member which comprises the lens-barrel 1 is demonstrated.

  The fixed frame 13 is a frame member having a cylindrical portion, and each member is accommodated in the inner peripheral portion, and the base portion 14 of the imaging unit 90 is fixed to the back surface portion. On the inner peripheral portion of the cylindrical portion of the fixed frame 13, a rotating frame cam groove 13 a that is inclined with respect to the optical axis O direction, a moving frame straight guide groove 13 c along the optical axis O direction, and a fourth group frame. The straight rectilinear guide groove 13b and a gear housing recess 13d in which a long gear 54 described later is housed are provided.

  A zoom drive unit 50 is disposed on the right side of the outer periphery of the cylindrical portion of the fixed frame 13, and a focus drive unit 60 is disposed on the upper left of the outer periphery of the cylindrical portion. A light shielding ring 35 is fixed to the front surface of the fixed frame 13.

  The rotating frame 11 is a substantially cylindrical frame member, and the rear end outer periphery is fitted into the inner peripheral portion of the fixed frame 13 in a state in which the rotating frame 11 can be rotated and retreated. A cam follower 11 b is disposed on the outer periphery of the rear end of the rotary frame 11. The cam follower 11 b is slidably fitted into the cam groove 13 a of the fixed frame 13.

  A gear portion 11 a that meshes with the long gear 54 is provided in a predetermined range on the outer periphery of the rear end portion of the rotary frame 11. The inner periphery of the rotating frame 11 is provided with a third group frame cam groove 11c and a cam frame rectilinear groove 11d which are inclined with respect to the optical axis O direction.

  The rotary frame 11 is driven to rotate around the optical axis O by the rotation of the long gear 54 driven by the zoom drive unit 50. The rotating frame 11 moves forward and backward in the optical axis O direction with the rotation around the optical axis O by the engagement of the cam follower 11 b and the cam groove 13 a of the fixed frame 13. A light shielding ring 34 and a decorative ring 33 are mounted on the outer periphery of the front surface of the rotary frame 11.

  The moving frame 10 is a frame member having a cylindrical portion, and the cylindrical portion is fitted into the inner peripheral portion of the rotating frame 11. A flange portion 10 a that bayonet-couples to the rotating frame 11 is provided at the rear end portion of the cylindrical portion of the moving frame 10. Further, a guide pin 10 b that protrudes radially outward from the rotating frame 11 and engages with the rectilinear guide groove 13 c of the fixed frame 13 is provided on the outer periphery of the rear end portion of the moving frame 10.

  The moving frame 10 is supported by the rotating frame 11 so as to advance and retreat in the optical axis O direction with respect to the rotating frame 11 and to be relatively rotatable around the optical axis O. The moving frame 10 moves in the direction of the optical axis O together with the rotating frame 11 in a state where the rotation around the optical axis O is restricted by the engagement between the guide pin 10b and the rectilinear guide groove 13c of the fixed frame 13. Move forward and backward.

  Further, the cylindrical portion of the moving frame 10 includes a cam frame cam groove 10c that passes through the cylindrical portion and is inclined with respect to the optical axis O, and a third group frame straight guide groove 10e that passes through the cylindrical portion. And a straight guide groove 10f for a float key carved on the inner peripheral portion of the cylindrical portion.

  The cam frame 5 is a cylindrical frame member, and is fitted into the inner peripheral portion of the moving frame 10 in a state where the cam frame 5 can rotate and retreat. A cam follower 5 d that protrudes radially outward is provided on the outer periphery of the rear of the cam frame 5. The straight guide pin 38 is fitted and fixed to the central portion of the cam follower 5d in a state of protruding outward.

  The cam follower 5d is slidably fitted into the cam groove 10c of the moving frame 10, and the rectilinear guide pin 38 is slidably fitted into the rectilinear groove 11d of the rotary frame 11 after passing through the cam groove 10c. Accordingly, the cam frame 5 is supported so as to be movable back and forth in the optical axis O direction along the cam groove 10 c of the moving frame 10 while rotating together with the rotating frame 11.

  Further, a cam groove 5a for the first group frame and a cam groove 5c for the second group frame are provided on the inner peripheral portion of the cam frame 5.

  The float key 9 is a frame member having a cylindrical portion, and a flange portion that is bayonet-coupled to the cam frame 5 is provided at a rear end portion. The float key 9 is supported so as to advance and retreat in the direction of the optical axis O with respect to the cam frame 5 and be relatively rotatable about the optical axis O.

  The float key 9 is provided with a guide protrusion 9a that protrudes radially outward from the flange portion. The guide protrusion 9 a of the float key 9 is slidably fitted into the straight guide groove 10 f of the moving frame 10. Therefore, the float key 9 is supported so as to be movable back and forth in the direction of the optical axis O together with the cam frame 5 in a state where the rotation around the optical axis O is restricted by the moving frame 10.

  The float key 9 is provided with a first-group frame rectilinear guide groove 9c carved on the outer peripheral portion of the cylindrical portion and a second-group frame rectilinear guide groove 9b penetrating the cylindrical portion.

  The first group frame 4 is a cylindrical frame member, and is fitted in the inner peripheral portion of the cam frame 5 so as to be able to advance and retreat in the direction of the optical axis O in a state where the rotation around the optical axis O is restricted. The first group frame 4 holds the first group lens 21, and a cam follower 36 is fixed to the outer peripheral portion. A guide protrusion (not shown) is slidably fitted into the straight guide groove 9 c of the float key 9 on the inner periphery of the first group frame 4.

  The cam follower 36 of the first group frame 4 is slidably fitted into the cam groove 5 a of the cam frame 5, and the rotation of the first group frame 4 around the optical axis O is restricted by the rectilinear guide groove 9 c of the float key 9. In this state, the cam frame 5 moves forward and backward in the direction of the optical axis O as the cam frame 5 rotates and advances and retracts.

  In front of the first group frame 4, a barrier device 3, which will be described in detail later, is disposed in a state of being covered with a decorative ring 2. The barrier device 3 includes a blade-shaped shielding member including a pair of inner shielding members 130 and a pair of outer shielding members 140. In the barrier device 3, the shielding member is retracted with the extension operation of the first group frame 4 from the retracted position, and the front surface of the first group lens 21 is opened. Further, the barrier device 3 moves the shielding member into the closed position as the first group frame 4 is retracted from the photographing position, thereby bringing the front surface of the first group lens 21 into a closed state.

  The second group frame 6 is a cylindrical frame member, and is fitted in the inner peripheral portion of the float key 9 so as to be able to advance and retreat in the direction of the optical axis O in a state where rotation around the optical axis O is restricted. The second group frame 6 is incorporated on the rear side of the first group frame 4. The second group frame 6 holds the second group lens 22, and is provided with three guide projections 6a and a cam follower 39 projecting radially outward from the center of the guide projection 6a on the outer periphery.

  The guide protrusion 6 a is slidably fitted into the straight guide groove 9 b of the float key 9, and the cam follower 39 is slidably fitted into the cam groove 5 c of the cam frame 5. Therefore, the second group frame 6 moves back and forth in the direction of the optical axis O in a state where the rotation around the optical axis O is restricted by the rotation and forward / backward movement of the cam frame 5.

  The third group frame 7 is a cylindrical frame member and is fitted into the inner peripheral portion of the float key 9. The third group frame 7 is incorporated behind the second group frame 6 so as to be movable back and forth in the direction of the optical axis O in a state where the rotation around the optical axis O is restricted. The third group frame 7 holds the third group lens 23, and further supports the shutter / aperture unit 8 on the inner peripheral portion on the back side so as to be relatively movable in the optical axis O direction.

  As will be described in detail later, a fixed aperture 7a, which is a first member, is fixed to the front side of the third group frame 7. Further, as shown in FIG. 6, the third group frame 7 is provided with arm portions that protrude radially outward in the circumferential direction. A guide projection 7b is provided at the tip of the arm, and a cam follower 41 that projects radially outward from the guide projection 7b is provided in the guide projection 7b.

  The guide protrusion 7 b is slidably fitted into the rectilinear guide groove 10 e of the moving frame 10, and the cam follower 41 is fitted into the cam groove 11 c of the rotating frame 11. Accordingly, the third group frame 7 moves back and forth in the direction of the optical axis O under a state in which the rotation around the optical axis O is restricted as the rotary frame 11 rotates.

  The shutter / diaphragm unit 8 is configured to have a shutter function for opening and closing the photographing optical path and an aperture function for adjusting the photographing light quantity. A compression spring 42 is inserted between the shutter / diaphragm unit 8 and the third group frame 7, and is urged away from each other.

  Since the shutter / aperture unit 8 is supported so as to be relatively movable in the direction of the optical axis O with respect to the third group frame 7 as described above, the lens barrel 1 shown in FIGS. The shutter / aperture unit 8 and the third group lens 23 are separated from each other by a predetermined distance in the direction of the optical axis O. On the other hand, as shown in FIG. 1, when the lens barrel 1 is retracted, the compression spring 42 is compressed by the close proximity of the third group frame 7 and the fourth group frame 12, and the shutter / diaphragm unit 8 and the third group lens 23 are compressed. Are in close contact with each other.

  In the present embodiment, the outer diameter of the rear portion of the third group lens 23 is smaller than the inner diameter when the shutter / aperture unit 8 is in the open state. Accordingly, the rear portion of the third lens group 23 can be allowed to enter the shutter / diaphragm unit 8 by opening the shutter / diaphragm unit 8 in the retracted state. Accordingly, in the present embodiment, the distance between the third group lens 23 and the fourth group lens 24 can be reduced, and the optical axis O direction can be reduced when the lens barrel 1 is retracted. .

  A conical coil spring 18 is disposed between the second group frame 6 and the third group frame 7 described above. The conical coil spring 18 biases the second group frame 6 and the third group frame 7 away from each other in the direction of the optical axis O. Due to the urging force of the conical coil spring 18, the backlash of the cam follower 39 of the second group frame 6 and the cam groove 5c of the cam frame 5 and the cam follower of the third group frame 7 when the lens barrel 1 is ready for photographing. The looseness of engagement between 41 and the cam groove 11c of the rotating frame 11 is eliminated. In addition, even in the retracted state, the backlash between the cam follower 39 of the second group frame 6 and the cam groove 5c of the cam frame 5 is eliminated.

  The fourth group frame 12 holds the fourth group lens 12 behind the shutter / diaphragm unit 8 and is disposed so as to be able to advance and retreat in the direction of the optical axis O in a state where rotation around the optical axis O is restricted. The fourth group frame 12 has two arms extending outward. One arm portion is provided with a guide protrusion 12c, and the other arm portion is provided with a guide shaft hole 12a and a feed screw insertion hole 12b.

  A guide shaft 65 supported by the fixed frame 13 is slidably fitted into the guide shaft hole 12a. The guide protrusion 12c is slidably fitted into the rectilinear guide groove 13b of the fixed frame 13. Accordingly, the fourth group frame 12 is supported so as to advance and retreat in the direction of the optical axis O along the guide shaft 65 and the straight guide groove 13b.

  The focus drive unit 60 includes a focus motor 61, a feed screw 66 that is rotationally driven by the focus motor 61, and a nut (not shown) that is screwed to the feed screw. The feed screw 66 is inserted into the feed screw insertion hole 12b of the fourth group frame 12 described above.

  In the fourth group frame 12, the arm provided with the feed screw insertion hole 12b engages with the nut, so that the driving force of the focus motor 61 causes the guide shaft 65 and the rectilinear guide groove 13b provided in the fixed frame 13 to move. Along the direction of the optical axis O.

  The zoom drive unit 50 includes a zoom motor 51, a gear train 53, and a long gear 54. The zoom motor 51 is fixed to the fixed frame 13 so that the output shaft is along the Y direction. A worm gear is fixed to the output shaft of the zoom motor 51.

  The gear train 53 includes a worm wheel that meshes with the worm gear of the zoom motor 51 and a reduction gear train that meshes with the worm wheel and meshes with the long gear 54.

  The long gear 54 is disposed in the gear housing recess 13 d of the fixed frame 13 so as to be rotatable around an axis parallel to the optical axis O. The long gear 54 meshes with the gear portion 11 a of the rotating frame 11.

  In the zoom drive unit 50, when the zoom motor 51 is rotationally driven during the retracting drive and zoom driving of the lens barrel 1, the rotary frame 11 is rotationally driven via the long gear 54, and the lens barrel 1 is extended or retracted. Is done.

  The imaging unit 90 is fixed to the back surface of the fixed frame 13. As shown in FIGS. 5 and 7, the imaging unit 90 includes a base portion 14, a Y frame 15 that is supported so as to be movable in the Y direction with respect to the base portion 14, and an X direction with respect to the Y frame 15. The X frame 16 is movably supported on the X frame, the image sensor 96 is fixedly supported on the X frame 16, the X drive unit 70, and the Y drive unit 80.

  The base portion 14 has a central opening portion 14a, and a rough projection shape seen from the front is centered on the optical axis O, and a lower right first corner portion 14b, an upper right second corner portion 14c, and an upper left portion. The frame member has a substantially rectangular shape having a third corner portion 14d and a lower left fourth corner portion 14e.

  The base portion 14 is fixed to the back surface portion of the fixed frame 13. Further, guide shafts 91 and 92, which are shaft members extending in the Y direction, are fixed to the left and right sides of the central opening 14a of the base unit 14, respectively.

  The third corner portion 14d has a notch, and the rear end portion of the focus drive unit 60 described above enters the notch. The fourth corner portion 14 e is a member arrangement relief portion in a state along the outer periphery of the fixed frame 13. The member arrangement relief portion serves as an escape portion for arranging the tripod female screw portion of the digital camera to which the lens barrel 1 is attached.

  The Y frame 15 is a frame member having an opening 15 a and is disposed in the central opening 14 a of the base portion 14. The Y frame 15 is supported by a pair of guide shafts 91 and 92 fixed to the base part 14 so as to be movable only in the Y direction with respect to the base part 14. Guide shafts 93 and 94, which are shaft members extending in the X direction, are fixed to the upper and lower sides of the opening 15a of the Y frame 15, respectively.

  The X frame 16 is a frame member having an opening 16 a and is disposed in the opening 15 a of the Y frame 15. The X frame 16 is supported by a pair of guide shafts 93 and 94 fixed to the Y frame 15 so as to be movable only in the X direction with respect to the Y frame 15. An image sensor 96 made of CCD, CMOS, or the like is fixed to the X frame 95 via an image sensor support plate 98.

  The X drive unit 70 is assembled to the front side of the upper right first corner portion 14 b of the base portion 14, and is arranged in a state of overlapping the rear position of the gear train 53 of the zoom drive unit 50 on the outer peripheral portion of the fixed frame 13. .

  The X drive unit 70 includes an X drive motor 71, an intermediate gear 73 meshing with a pinion of the output shaft of the X drive motor 71, a feed screw 74 to which the intermediate gear 73 is fixed and extending in the X direction, A nut 75 that is screwed onto the screw 74 is provided.

  The feed screw 74 is rotated by the driving force of the X drive motor 71. The nut 75 is screwed into the feed screw 74 in a state where the rotation is restricted, and engages with the U-shaped notch 16 b of the X frame 16. Therefore. When the X drive motor 71 is rotationally driven, the nut 75 and the X frame 16 are displaced in the X direction by the feed screw 74.

  The Y drive unit 80 is assembled on the front surface side of the second corner portion 14 c of the base portion 14, and is disposed above the zoom motor 51 on the outer peripheral portion of the fixed frame 13. The Y drive unit 80 includes a Y drive motor 81, an intermediate gear 83 meshing with a pinion of the output shaft of the Y drive motor 81, a feed screw 84 to which the intermediate gear 83 is fixed and extending in the Y direction, A nut 85 that is screwed onto the screw 84 is provided.

  The feed screw 84 is rotated by the driving force of the Y drive motor 81. The nut 85 is screwed into the feed screw 84 in a state where its rotation is restricted, and engages with the U-shaped notch 15 b of the Y frame 15. Therefore. When the Y drive motor 81 is driven to rotate, the nut 85 and the Y frame 15 are driven to move in the Y direction by the feed screw 84.

  In the present embodiment, in the lens barrel 1 described above, the exterior color of the zoom motor 51, the focus motor 61, the Y drive motor 81, and the X drive motor 71 is black or other than black, for example, silver. The exterior color of the fixed frame 13 and the base unit 14 is a color other than black, for example, silver or black. Thus, for example, each motor of the zoom motor 51, the focus motor 61, the Y drive motor 81, and the X drive motor 71 in a state in which the assembly state during the assembly process is confirmed by making the exterior color of the component member and the motor different. Can be fixed to the fixed frame 13 by confirming that the fixed frame 13 and the base portion 14 are mounted at the predetermined positions described above.

  Next, in the lens barrel 1 of the present embodiment, a configuration in which the fixed diaphragm 7a is fixed to the front surface portion of the third group frame 7 will be described in detail.

  As shown in FIGS. 6, 9 and 10, the fixed diaphragm 7 a which is the first member is a substantially disk-shaped member, and a diaphragm opening which is a circular through hole centered on the optical axis O. 7d is provided. A plurality of engaging claw portions 130, a plurality of positioning projections 140, and a rotation stop boss portion 151 are provided on the back side of the fixed aperture 7a so as to protrude rearward.

  In the present embodiment, the plurality of engaging claws 130 are equally distributed around the diaphragm opening 7d of the fixed diaphragm 7a at three locations in the circumferential direction with the optical axis O as the center. The rear end portions of the plurality of engaging claws 130 extend radially outward from the optical axis O to a predetermined radius R4.

  The plurality of positioning protrusions 140 are equally distributed at three positions around the optical aperture O at a position around the aperture opening 7d of the fixed aperture 7a and not overlapping the engaging claw 130 described above in the circumferential direction. Has been. The inner peripheral surfaces of the plurality of positioning protrusions 140 facing the optical axis O constitute a first cylindrical portion having a predetermined radius R2 with the optical axis O as the center. Further, the rear side surfaces (tip surfaces) of the plurality of positioning projections 140 are formed as a part of the same plane that is orthogonal to the optical axis O and spaced rearward from the fixed diaphragm 7a by a predetermined distance.

  The rotation stop boss 151 is provided at the tip of the arm 150 that extends radially outward from the fixed aperture 7a at a position that does not overlap the engagement claw 130 and the positioning protrusion 140 in the circumferential direction. ing. The rotation stop boss 151 has a cylindrical shape with a predetermined diameter in the present embodiment, and has a height that protrudes rearward from the positioning protrusion 140 described above.

  The front portion of the third group frame 7 as the second member is substantially circular as shown in FIGS. 8 and 10 and is provided with a recess 121 that is recessed toward the rear at the center. The concave portion 121 has a substantially circular inner peripheral shape that can accommodate the fixed diaphragm 7a described above when viewed from the optical axis O direction. A holding frame portion 7 c for holding the third group lens 23 is provided on the bottom surface of the recess 121. A plurality of engagement hole portions 110, a plurality of positioning projections 122, and a boss insertion hole 120 are provided around the holding frame portion 7 c on the bottom surface portion of the recess 121.

  The plurality of positioning protrusions 122 protrude forward from the bottom surface of the recess 121. The plurality of positioning protrusions 122 are equally arranged at three locations in the circumferential direction around the optical axis O. The outer peripheral surfaces of the plurality of positioning protrusions 122 facing outward in the radial direction constitute a second cylindrical portion having a predetermined radius R1 with the optical axis O as the center.

  Here, the outer peripheral surface of the second cylindrical portion having the radius R1 formed by the plurality of positioning projections 122 of the third group frame 7 is the first of the radius R2 formed by the plurality of positioning projections 140 of the fixed aperture 7a. Into the inner peripheral surface of the cylindrical portion 2 is fitted with a predetermined fit tolerance. As a result, the radial position of the optical axis O of the fixed diaphragm 7a is determined with respect to the third group frame 7.

  The height of the plurality of positioning protrusions 122 is lower than the height of the plurality of positioning protrusions 140 of the fixed aperture 7a. Accordingly, the plurality of positioning protrusions 140 of the fixed aperture 7a abut on the bottom surface of the recess 121, whereby the fixed aperture 7a is positioned rearward in the optical axis O direction with respect to the third group frame 7.

  The plurality of engagement hole portions 110 are through holes that engage with each other in a state where the plurality of engagement claw portions 130 of the fixed aperture 7a are inserted therein. The plurality of engagement hole portions 110 are respectively disposed at positions corresponding to the plurality of engagement claw portions 130 of the fixed aperture 7a. In other words, the plurality of engagement hole portions 110 are equally arranged at three locations in the circumferential direction with the optical axis O being substantially the center.

  Further, when viewed from the direction of the optical axis O, the plurality of engagement holes 110 are formed such that the radially outer peripheral surface is a part of a cylindrical surface having a predetermined radius R3 with the optical axis O as the center. Has been. The value of radius R3 is smaller than the value of radius R4.

  Further, when viewed from the optical axis O direction, the plurality of engagement hole portions 110 are formed such that the radial width changes in two steps as it goes in one circumferential direction. Specifically, as shown in FIG. 8, when viewed from the front in the optical axis O direction, the plurality of engagement holes 110 are two holes having different widths in the radial direction. The hole portion 110a and the second engagement hole portion 110b are configured to be connected in the circumferential direction.

  The first engagement hole 110a is disposed on the counterclockwise side of the engagement hole 110 when viewed from the front in the optical axis O direction, and has a predetermined radial width W1. The second engagement hole 110b is disposed on the clockwise side of the engagement hole 110 when viewed from the front in the optical axis O direction, and has a radial width W2 that is narrower than the width W1.

  As described above, since the inner peripheral surface on the radially outer side of the plurality of engagement hole portions 110 has a substantially constant radius R3 from the optical axis O, the first engagement hole portion 110a has the second It enters inward in the radial direction from the engagement hole 110b.

  Further, the value of the radial width W1 of the first engagement hole portion 110a is larger than the radial thickness T2 including the portion extending outward in the radial direction of the engagement claw portion 130 of the fixed aperture 7a. Further, the value of the radial width W2 of the second engagement hole portion 110b is larger than the radial thickness T1 excluding the portion extending outward in the radial direction of the engagement claw portion 130 of the fixed aperture 7a, and It is smaller than the radial thickness T2 including the portion extending radially outward of the engaging claw 130.

  That is, as shown in FIG. 12, the engaging claw 130 provided on the fixed aperture 7a can be inserted into the engaging hole 110 on the first engaging hole 110a side having a radial width W1. It is. In the state in which the plurality of engagement claw portions 130 of the fixed aperture 7a are inserted into the first engagement hole portions 110a of the plurality of engagement hole portions 110, the plurality of engagement claw portions 130 have a plurality of engagement holes. The part 110 is engaged in a form called a so-called snap fit.

  In this engaged state, the bottom surface of the recess 121 is sandwiched in the direction of the optical axis O by the plurality of positioning protrusions 140 and the plurality of engaging claws 130 of the fixed aperture 7a. The fixed diaphragm 7a is positioned in the optical axis O direction.

  Then, after inserting the plurality of engaging claws 130 of the fixed aperture 7a into the plurality of engaging holes 110, respectively, the fixed aperture 7a is clockwise when viewed from the front in the optical axis O direction with respect to the third group frame 7. As shown in FIG. 13, the plurality of engaging claws 130 move into the second engaging hole 110b having a radial width W2.

  In the state shown in FIGS. 13 and 11, the plurality of engaging claw portions 130 of the fixed aperture 7 a are engaged with each other while being inserted into the plurality of engaging hole portions 110. In this state, the radial width W2 of the second engagement hole 110b is smaller than the radial thickness T2 of the plurality of engagement claws 130 of the fixed aperture 7a. Is sandwiched by the inner peripheral surface of the second engagement hole portion 110b with a predetermined fit in the radial direction of the optical axis O. As a result, the plurality of engaging claws 130 are prevented from falling off from the engaging hole 110.

  As shown in FIG. 11, the boss insertion hole 120 is in a state where the plurality of engagement claw portions 130 of the fixed aperture 7 a are inserted and engaged with the second engagement hole portions 110 b of the plurality of engagement hole portions 110. The through-hole into which the rotation-stop boss 151 of the fixed aperture 7a is fitted with a predetermined fit.

  The rotation stop boss portion 151 of the fixed diaphragm 7a is fitted into the boss insertion hole 120 of the third group frame 7, whereby the circumferential positioning around the optical axis O of the fixed diaphragm 7a is performed with respect to the third group frame 7. . Further, by this positioning, the plurality of engaging claw portions 130 of the fixed throttle 7a are held in a state of being inserted into the second engaging hole portions 110b of the plurality of engaging hole portions 110. 7a can be prevented from falling off from the third group frame 7.

  According to the present embodiment described above, it is possible to quickly position the fixed aperture 7a on the third group frame 7 with a predetermined accuracy without using an adhesive, and fix it without failure.

  In the present embodiment, the present invention is applied to the case where the fixed diaphragm 7a is fixed to the third group frame 7. However, the present invention is also applicable to the case where the lens holding member that holds the lens is fixed to another frame member. Applicable.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Is also included in the technical scope of the present invention.

  The lens barrel according to the present invention is not limited to the digital camera described in the above embodiment, but is an electronic device having a photographing function, such as a recording device, a mobile phone, a PDA, a personal computer, a game machine, a digital media player, and a television. It can also be applied to lens barrels provided in GPS, watches, etc.

  Further, the lens barrel according to the present invention is applicable not only to an electronic device having a photographing function but also to a lens barrel for an interchangeable lens camera, and is provided in a projection display device such as a projector. It can also be applied to a lens barrel. The lens barrel according to the present invention can also be applied to other forms of optical equipment such as telescopes and binoculars.

1 lens barrel,
3 barrier device,
4 1 group frame,
5 Cam frame,
6 Group 2 frame,
7 Group 3 frame (second member),
7a Fixed throttle (first member),
7c holding frame,
7d Aperture opening (opening),
8 Shutter / aperture unit,
9 Float key,
10 Movement frame,
11 Rotating frame,
12 4 group frame,
13 Fixed frame,
50 zoom drive unit,
60 focus drive unit,
90 imaging unit,
110 engagement hole,
110a first engagement hole,
110b second engagement hole,
120 boss insertion hole,
121 recess,
122 positioning protrusion (second cylindrical portion),
130 engaging claw,
140 Positioning protrusion (first cylindrical portion)
150 arms,
151 Anti-rotation boss.

Claims (3)

A holding frame for holding the lens;
A first member disposed in any one of the optical axis directions of the lens of the holding frame and having an opening through which the optical axis of the lens passes;
A lens barrel that includes the second member that holds the holding frame and holds the first member relative to the holding frame;
A plurality of engagement claws disposed around the opening of the first member in the circumferential direction of the optical axis and extending toward the second member;
A plurality of first members disposed around the holding frame portion of the second member at positions corresponding to the plurality of engagement claw portions and engaged with the plurality of engagement claw portions inserted. Engagement holes,
The first engagement hole is connected to one side in the circumferential direction of the optical axis, is narrower in the radial direction than the first engagement hole, and the first member is made to be smaller than the second member. When the plurality of engaging claws are inserted, the engaging claws are engaged with each other in the radial direction of the optical axis. A plurality of second engagement holes sandwiched by fitting;
A first cylindrical portion protruding from the first member toward the second member with the optical axis as a center;
A second cylindrical portion projecting from the second member toward the first member around the optical axis, and fitting with the first cylindrical portion;
A rotation stop boss projecting from the first member toward the second member around the optical axis;
The second member is provided on the second member and is engaged with the rotation-stop boss portion in a state where the plurality of engaging claws are engaged with the plurality of second engaging holes. And a boss insertion hole for restricting rotation of the first member about the optical axis relative to the lens barrel.   The lens barrel according to claim 1, wherein the opening of the first member is a fixed diaphragm.   The lens barrel according to claim 1, wherein the first member is a lens holding member that holds a lens.

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