JP2007334245A - Lens barrier mechanism and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem, wherein regarding conventional lens barrier mechanisms, it is necessary to make two blades retreat outward by a large amount, then the area of the principal surface in the retreating direction is increased, and the mechanism as a whole is made large in size. <P>SOLUTION: The lens barrier mechanism is arranged ahead of an objective lens, and includes two pairs of blade connectors 41 and 42 configured to open/close an aperture part 51 for transmitting light from an object, and constituted of first blades 46 and 47 and second blades 48 and 49 connected turnably. Two first blades 46 and 47 are supported freely turnably by a pair of pivot shafts 54a and 54b provided on a barrier support plate 43 and are arranged adjacent to each other. Two second blades 48 and 49 are supported freely turnably by the two first blades through a pair of connection shafts 53 and 53. A pair of operation arms 59 and 59 for moving the two pairs of blade connectors 41 and 42 between a closed position, where the two pairs of blade connectors 41 and 42 are closed and an open position where the connectors 41 and 42 are opened are arranged near the pair of pivot shafts for the two first blades. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens barrier mechanism that is disposed in front of an objective lens to protect a lens and that opens and closes the optical path of the lens, and an imaging apparatus that includes the lens barrier mechanism.

  In general, an imaging apparatus is provided with a lens barrier mechanism that is disposed in front of an objective lens facing a subject and covers the objective lens in order to protect the lens. In this lens barrier mechanism, in order to reduce the size of an imaging device such as a camera and improve the degree of freedom in designing to improve the lens performance, the opening portion facing the objective lens is enlarged while reducing the overall size. It is demanded. In order to achieve this object, it is preferable to have a structure in which the blade portion covering the larger opening can be retracted to as small an area as possible. In addition, it is desired to have a simpler structure in order to improve the reliability and productivity of the lens barrier mechanism.

  However, in this type of conventional lens barrier mechanism, two or four blades that open and close the opening and a ring member that rotates around the opening are provided, and the ring member is rotated to provide two sheets. Alternatively, there are many mechanisms that rotate four blades. For this reason, in the lens barrier mechanism having such a structure, not only the parts become large, but also the rotating ring exists over a wide range, and therefore it is necessary to make the structure capable of avoiding the influence of dust and the like over the wide range. As a result, there are problems such as strict accuracy control of components and the need to adopt a complicated structure for dust prevention, which is not an advantageous structure in terms of mechanism reliability and productivity. It was.

  As a specific example of a conventional lens barrier mechanism of this type, for example, there is a patent application previously filed by this applicant and described in Patent Document 1. Patent Document 1 describes a lens cover of a camera built-in type that opens and closes the front surface of a lens such as a video camera. The lens cover described in Patent Document 1 is “two semi-circular lens cover bodies are rotatably supported by a support shaft portion, and the two lens cover bodies are developed in a substantially circular shape. The front surface of the lens is closed in the closed state, and the front surface of the lens is opened in the overlapped state ”.

  According to the lens cover having such a configuration, “when the lens front surface is opened, two semi-circular lens cover bodies are superposed, so that the lens cover storage space when the lens is opened is reduced. As a result, the volume of the camera body is small and the camera can be miniaturized (paragraph number [0020] in the specification).

  As another conventional lens barrier mechanism, there is, for example, a patent application previously filed by the present applicant and described in Patent Document 2. Japanese Patent Application Laid-Open No. H10-228667 describes an imaging apparatus in which a lens opening is opened and closed by a relative rotation operation of two blades. The imaging device disclosed in Patent Document 2 is “imaging having first and second cover blades in which a closed state covering the front surface of the lens and an open state opening the front surface of the lens are reversibly operated. In the apparatus, the two cover blades are pivotally connected to each other by a pivot while being overlapped with each other, and are biased in a direction away from each other by an elastic body, and the first cover blade is disposed in the vicinity of the pivot. The second cover blade is rotated by an operation pin provided on a member fixed to the main body side, and is supported by a rotation shaft provided on a member fixed to the main body side. The front surface of the lens can be freely opened and closed by rotating the first cover blade and interlocking the second cover blade ”.

  According to the imaging apparatus having such a configuration, “by rotating the first cover blade, the second cover blade is pressed by the pressing force of the operation pin against the spring force of the torsion spring. It is possible to obtain an effect that the lens is rotated and the front surface of the lens is opened (paragraph number [0014] in the specification).

  Further, as another example of the conventional lens barrier mechanism, there is one described in Patent Document 3, for example. Patent Document 3 describes a barrier mechanism for protecting a lens such as a camera. The barrier mechanism described in Patent Document 3 is “supported by being attached to the distal end portion of the photographing lens and overlapping in the optical axis direction freely when moving between a closed position for closing the photographing opening at the distal end portion and an open position for opening the photographing lens. A plurality of barrier blades, and a barrier mechanism in which at least one barrier blade is driven to an open position and a closed position, and one barrier blade is connected to the one barrier blade and the other barrier blade. In the process of moving from the open position to the closed position, the other barrier blades move together to the closed position, and in the process of moving to the closed position, the one barrier blade and the other barrier blade are in the closed position. A closed positioning locking portion for preventing the movement of the other barrier blade and holding each barrier blade in the closed position.

According to the imaging apparatus having such a configuration, “the number of positioning members can be reduced and the space in the lens can be saved. Therefore, the photographing lens can be made compact and the cost can be reduced (paragraph number [0021] in the specification). ]) ”Is expected.
JP-A-6-38082 JP 2005-308898 A JP-A-7-152066

  However, in the conventional lens barrier mechanism disclosed in Patent Document 1 and Patent Document 2, in any case, a pair of blades composed of a combination of the first blade and the second blade is used. The opening was opened and closed. For this reason, when opening the opening, it is necessary to retract the two blades to the outside greatly, so that there is a problem that the area of the main surface in the retracting direction is increased and the entire mechanism is enlarged.

  Moreover, in the conventional lens barrier mechanism disclosed in Patent Document 3, two sets of blade coupling bodies combining the first blade and the second blade, and a total of four sheets constituting the two sets of blade coupling bodies In this configuration, a ring member for opening and closing the blades is provided, and by rotating the ring member, the four blades are cam-driven to open and close the opening. For this reason, since the rotating ring exists over a wide range, it is necessary to make the structure capable of avoiding the influence of dust and the like over a wide range, the entire mechanism becomes complicated, and the accuracy control of the component parts becomes strict. There was a problem that a complicated structure for dust prevention had to be adopted.

  The problem to be solved is that in the conventional lens barrier mechanism, it is necessary to retract the two blades to the outside greatly, so that the area of the main surface in the retracting direction is increased, and the entire mechanism is enlarged. It is that. In addition, the structure must be able to avoid the influence of dust over a wide range, so the entire mechanism becomes complicated, and the precision control of components must be tightened, or a complicated structure for dust prevention must be adopted. It must be.

  The lens barrier mechanism of the present application includes two sets of blade coupling bodies that are disposed in front of an objective lens directed to a subject and that can open and close an opening through which light from the subject passes. The coupling body is a lens barrier mechanism composed of a first blade and a second blade that are rotatably connected to each other. The two first blades are rotatably supported by a pair of pivots provided on a barrier support plate having an opening and arranged at adjacent positions, and the two second blades are opposite to the pivots. And is rotatably supported by the two first blades by a pair of connecting shafts disposed adjacent to each other. Provided in the vicinity of the pair of pivots of the two first blades is an interlocking operation unit that moves the two sets of blades linked between the closed position that closes the opening and the open position that opens the opening. Is the most important feature.

  According to the lens barrier mechanism and the imaging apparatus of the present application, by operating the interlocking operation unit, the two first blades are rotated around the pair of pivots, and the two second blades together with the two first blades. The blade is rotated. As a result, the two sets of blade coupling bodies are selectively moved to a closed position for closing the opening provided in the barrier support plate and an open position for opening the opening. As a result, the opening is composed of four blades. Is opened and closed by. At this time, by operating the interlock operation unit, the two sets of blade coupling bodies are interlocked and rotated to open and close the opening, so that the configuration of the lens barrier mechanism can be made extremely simple. Therefore, it is possible to reduce the size of the entire mechanism by reducing the size of the component parts.

  Of the two sets of blade coupling bodies formed by the first blade and the second blade, the two first blades are rotatably supported on the barrier support plate by a pair of pivots arranged at adjacent positions. At the same time, the two second blades are rotatably supported on the two first blades by a pair of shaft pins arranged at adjacent positions on the opposite side to the pair of pivots, and a pair of the two first blades. An interlocking operation unit is provided near the pivot axis. As a result, a lens barrier mechanism that can open and close the opening reliably while having a small number of parts, a simple structure, and a small size can be realized with a simple configuration, and an imaging device including the lens barrier mechanism can be realized. An apparatus can be provided.

  1 to 29 show examples of embodiments of the present invention. 1 is an external perspective view showing a first embodiment of the lens barrier mechanism of the present invention, FIG. 2 is a perspective view seen from the front side, and FIG. 3 is a state in which the opening seen from the back side is closed. FIG. 4 is a perspective view in a state where the opening is similarly opened, FIG. 5 is a perspective view in which a part of the interlocking drive mechanism is disassembled, and FIG. 6 is an explanatory view showing a state in which a case member is mounted on the barrier support plate. FIG. 7 is an explanatory view for explaining the relationship between the two sets of blade coupling bodies and the interlocking drive mechanism, FIG. 8 is an explanatory view of a state in which the opening of the barrier support plate is closed by the two sets of blade coupling bodies, and FIG. FIG. 10 is an exploded perspective view, FIG. 10 is a perspective view showing the first blade and the second blade, FIG. 11 is an explanatory view showing an enlarged main part of FIG. 10, and FIGS. FIG.

  FIGS. 13 to 16 are views for explaining a state in which the opening of the barrier support plate is opened and closed by two sets of blade coupling bodies, FIGS. 17A and 17B are explanatory views showing enlarged main parts, and FIGS. FIGS. 21A and 21B are explanatory views showing enlarged main parts, and FIGS. 24 and 25 are interlocking drive mechanisms. FIGS. 26A and 26B are explanatory diagrams of the interlocking drive mechanism, FIG. 27 is an explanatory diagram of the position detection mechanism, and FIG. 28 is an example of the first embodiment of the imaging apparatus of the present invention. FIG. 29 is a perspective view as seen from the back side.

  First, an imaging apparatus according to the present invention will be described. 28 and 29 show a digital video camera 1 shown as a first embodiment of the imaging apparatus of the present invention to which the lens barrier mechanism of the present invention is applied. This digital video camera 1 uses two types of information storage media, and can selectively record information signals on the respective information storage media and reproduce the recorded information. It is.

  Of the two information storage media used in the digital video camera 1, the first is a tape-like storage medium (for example, a tape cassette) in which a magnetic tape is housed in a cassette case, and the second is plastic. A semiconductor storage medium (for example, a memory card) in which an LSI such as a CPU and a memory is built in a card. The digital video camera 1 selectively uses these information storage media, converts an optical image into an electrical signal by an image sensor such as a CCD or CMOS, and converts the image information into a tape-shaped storage medium or a semiconductor. The information can be recorded on a storage medium or displayed on a display device including a flat panel such as a liquid crystal display.

  The digital video camera 1 travels on an exterior case 2 formed as a casing, and a magnetic tape of a tape cassette as a first information storage medium that is housed in the exterior case 2 and is detachably mounted. Then, a tape drive device that records (writes) and reproduces (reads) information signals, a control circuit that performs drive control of the tape drive device, and a lens device 3 that captures an image of a subject as light and guides it to the image sensor. And a display device 4 and the like that are rotatably attached to the outer case 2.

  As shown in FIGS. 28 to 29, the outer case 2 is formed of a hollow casing having a substantially cylindrical shape, and is used in a state where the axial direction is set to the front-rear direction. A lens device 3 having substantially the same thickness is disposed at the front portion of the outer case 2. The lens device 3 is attached to the exterior case 2 with the optical axis of the lens system oriented in the horizontal direction. Inside the exterior case 2, an imaging element made of CCD, CMOS, or the like is attached to the rear part of the lens device 3. A viewfinder device 5 is disposed behind the lens device 3.

  An opening for exposing an accessory shoe to which an accessory such as a video light or an external microphone is detachably attached is provided in the upper part of the outer case 2. The accessory shoe is disposed above the lens device 3 and is normally detachably covered with a shoe cap 6 that opens and closes the opening. Furthermore, a stereo microphone 7 is provided in the lower part of the front surface of the outer case 2. The light emitting unit 8 of the flash device is disposed on the upper part of the front surface of the lens device 3.

  Further, the display device 4 is attached to one side surface of the exterior case 2 so that the posture can be changed. The display device 4 includes a flat panel 11 made of a flat liquid crystal display, a panel case 12 in which the flat panel 11 is accommodated, and a panel support that supports the panel case 12 with respect to the exterior case 2 so that the posture can be changed. Part 13. The panel case 12 is formed of a flat housing having a substantially rectangular parallelepiped shape, and an opening window 15 for exposing the display surface of the flat panel 11 is provided on a surface facing one side surface of the exterior case 2. The opening window 15 is formed of a rectangular through hole extending in the longitudinal direction, and four sides surrounding the opening window 15 are rectangular frame portions 12a. On the opposite side of the frame portion 12a of the panel case 12 from the panel support portion 13, a plurality of operation buttons 16 for operating the flat panel 11 are disposed.

  The panel support unit 13 includes a horizontal rotation unit that allows the panel case 12 to rotate about 90 degrees in the horizontal direction about the vertical axis, and a panel case 12 about 180 in the front-rear direction about the horizontal axis. In addition, it has a front-rear rotation part that can rotate approximately 90 degrees in the up-down direction and can rotate approximately 270 degrees in total. Thereby, as shown in FIG. 29, the display device 4 rotates the panel case 12 in the horizontal direction by 90 degrees so that the flat panel 11 faces rearward, and the storage state stored in the side surface of the exterior case 2. 29, the panel case 12 is rotated 180 degrees from the state shown in FIG. 29 and the flat panel 11 is opposed to the front, and the flat panel 11 is further rotated 90 degrees rearward from the state where the flat panel 11 is opposed to the rear. A state in which the panel 11 is directed downward and an arbitrary state (posture) at an intermediate position between them can be taken.

  On the side surface of the exterior case 2 that is opened and closed by the display device 4, a storage recess 17 is provided that is recessed to store a part of the display device 4 on the flat panel 11 side. As shown in FIG. 29, the storage recess 17 has a shape commensurate with the outer shape of the panel case 12, and has a storage medium insertion slot 18 of the storage medium storage section, an external peripheral device, and an electric A USB connector 19 is provided for connection. A plurality of through holes 21 are provided in the vicinity of the storage medium insertion port 18 in order to emit sound from the built-in speaker device.

  As shown in FIG. 28, a gripping portion 22 for gripping the exterior case 2 is provided on the side surface of the exterior case 2 opposite to the display device 4. The grip portion 22 serves as both a disk drive device housed therein and a cover member of a mechanical deck that does not appear in the drawing and a mechanical deck. By opening the upper portion of the grip portion 22 outward, the cassette insertion slot of the built-in mechanical deck is exposed, and the tape cassette can be attached and detached. The opening operation of the grip portion 22 is released by sliding the lock release button 23 provided on the upper portion of the grip portion 22 backward, and after the lock is released, it can be manually operated (may be an automatic operation). Performed by opening to the side. On the other hand, the closing operation of the grip portion 22 is executed by pressing the grip portion 22 in the open state inward and pushing it to a predetermined position.

  A power switch 24 that also serves as a mode selection switch, a shutter button 25 that captures a still image, and an image are continuously enlarged (tele) or reduced (wide) within a predetermined range at the upper rear of the grip 22. A zoom button 26 is provided. The power switch 24 has a function of switching the power on and off by a turning operation and a function of switching so as to repeat a plurality of function modes by turning the power while the power is turned on. Below the power switch 24, a recording button 27 for taking a moving image is provided.

  Further, a hand belt 28 is attached to the lower portion of the grip portion 22 so as to be bridged in the front-rear direction, and a hand pad 29 is attached to the hand belt 28. The hand belt 28 and the hand pad 29 support the user's hand holding the grip portion 22 of the outer case 2 and prevent the digital video camera 1 from being removed.

  As shown in FIG. 29, on the back surface of the exterior case 2, there is provided a battery housing portion 31 in which a battery device as a portable power source is detachably mounted. The battery housing portion 31 is configured as a concave portion that is continuous from the center portion to the lower surface of the back surface of the outer case 2. A viewfinder device 5 having a half-moon-shaped dome shape is disposed above the battery housing 31.

  The lens device 3 built in the digital video camera 1 having such a configuration is configured to have a configuration as shown in FIG. 1, for example. The lens device 3 includes a lens barrel 33 formed in a cylindrical shape, and a lens system including a combination of a plurality of lenses attached to the lens barrel 33. A plurality of lenses constituting the lens system are supported by a lens barrel 33 so as to be fixed or movable. Among the plurality of lenses of the lens system, an objective lens 34 directed to the subject is disposed at one end of the lens barrel 33. An image sensor (CCD, CMOS, etc.) is disposed at the other end of the lens barrel 33. The other lens system lens is fixed or movably attached between the objective lens 34 and the image sensor.

  A lens barrier mechanism 40 that covers and protects the objective lens 34 is disposed in front of the lens device 3 on the subject side. A decorative ring 36 is attached in front of the lens barrier mechanism 40, and the decorative ring 36 is exposed on the front surface of the exterior case 2. An optical path hole 37 through which light from the subject passes and a through hole 38 through which the light emitting unit 8 of the flash device is exposed are provided on the front surface of the decorative ring 36. The optical path hole 37 is opened in a circular shape at a substantially central portion of the end face of the decorative ring 36, and a through hole 38 having a substantially crescent shape is opened in one of the radial directions (for example, upward).

  The lens barrier mechanism 40 supports two sets of blade coupling bodies 41 and 42 including a first blade coupling body 41 and a second blade coupling body 42, and rotatably supports the two sets of blade coupling bodies 41 and 42. And a case member 44 for holding the barrier support plate 43, an interlocking operation mechanism 45 for rotating the two sets of blade coupling bodies 41 and 42, and the like.

  The two sets of blade coupling bodies 41 and 42 have a substantially bilaterally symmetric shape, and are composed of a combination of first blades 46 and 47 and second blades 48 and 49 that are rotatably connected to each other. . The first blade 46 of the first blade connector 41 and the first blade 47 of the second blade connector 42, and the second blade 48 and the second blade connector 42 of the first blade connector 41. The second blade 49 has a substantially bilaterally symmetric shape. Therefore, about the structure and assembly process of 2 sets of blade | wing connection bodies 41 and 42 demonstrated here, the 1st blade | wing connection body 41 is demonstrated on behalf of both, and the overlapping description is abbreviate | omitted.

  FIG. 10 shows a first example of the first blade connection body. The first blade connection body 41 includes a first blade 46 and a second blade 48, both of which are thin plate-like. It is composed of The first blade 46 is a main component of the first blade connector 41, and a second blade 48 that is a subordinate component is superimposed on one surface of the first blade 46. Then, the combination of the first blade 46 and the second blade 48 is configured to open and close a half region of the opening 51 provided in the barrier support plate 43. The remaining half of the opening 51 is opened and closed by the second blade coupling body 42.

  The 1st blade | wing 46 consists of the shielding part 46a which can obscure substantially 1/2 area | region of the opening part 51, and the operation part 46b continuous on the one side of this shielding part 46a. The shielding part 46a of the first blade 46 is made of a substantially rectangular face plate formed slightly larger than a substantially half area of the opening 51, and is arranged on one side in the width direction on the side where the operation part 46b is continuous. Is provided with a notch 52 for opening the optical path. The notch 52 has an opening 51 in the vicinity of the center of rotation when the first blade 46 rotatably supported by the barrier support plate 43 moves outward to open the opening 51. This is provided to remove the overlapping portion. A gap generated by the notch 52 is closed by the second blade 48.

  On one surface of the shielding portion 46a of the first blade 46, that is, the surface on which the second blade 48 is stacked, a connecting shaft 53 for rotatably connecting the second blade 48 and the second blade A first blade stopper 54 and a second blade stopper 55 that restrict the rotation range of 48 are provided. The connecting shaft 53 is formed of a cylindrical convex portion and is erected on the side away from the operation portion 46b and in the vicinity of the contact portion 56 that is in contact with the first blade 48 of the second blade connecting body 42. Has been. A pair of retaining protrusions 53a, 53a for retaining are provided at the distal end of the connecting shaft 53 so as to project on both sides in a certain diameter direction. In this embodiment, the pair of retaining protrusions 53a and 53a are arranged in a direction orthogonal to the direction in which the contact portion 56 that contacts the first blade 48 of the second blade connector 42 extends. Yes.

  The first blade stopper 54 of the first blade 46 is formed so as to protrude on the side opposite to the contact portion 56 of the shielding portion 46 a and closer to the operation portion 46 b than the connecting shaft 53. Further, the second blade stopper 55 is disposed at a position farthest from the operation portion 46 b of the shielding portion 46 a and away from the contact portion 56. Further, a positioning projection 57 that prevents the first blade 46 from rotating in the direction of closing the opening 51 and positions the central blade at a predetermined position at the position farthest from the operation portion 46b of the shielding portion 46a. Is provided.

  The operation part 46b of the first blade 46 extends on the opposite side to the direction in which the shielding part 46a extends, and a boss part 58 and an operation arm 59 are provided at the tip part. A pivot provided on the barrier support plate 43 is rotatably inserted into the boss hole of the boss portion 58, and the first blade 46 is pivoted about the pivot. The operation arm 59 has one end continuous to the boss portion 58 and the other end protruding in the direction intersecting with the direction in which the operation portion 46 b extends and on the side where the contact portion 56 is located. The operation arm 59 is provided with a step so as to overlap with each other and intersect within a predetermined range with respect to the operation arm 59 provided on the first blade 48 of the second blade coupling body 42.

  Further, the operation portion 46b of the first blade 46 is provided with a spring receiving pin 62 for locking one end of a coil spring 61 showing a specific example of the urging member. A guide protrusion 63 that guides the second blade 48 is provided in the vicinity of the operation portion 46b of the shielding portion 46a. The guide ridge 63 extends in an arc shape because the second blade 48 rotates.

  The second blade 48 includes a shielding portion 48a having a size capable of covering the cutout portion 52 provided in the shielding portion 46a of the first blade 46, and a regulating portion continuous to one side of the shielding portion 48a. 48b. The shielding part 48 a of the second blade 48 has a length that is about the same as the shielding part 46 a of the first blade 46, and has a protrusion 65 for covering the notch 52. Furthermore, the shielding part 48a is provided with a connection hole 66 through which the connection shaft 53 of the first blade 46 passes. As shown in FIG. 11, the connecting hole 66 is a bearing hole with a counterbore surface 66a, and the counterbore surface 66a allows a pair of retaining projections 53a and 53a provided on the connecting shaft 53 to pass therethrough. A slit 66b is provided.

  The connecting hole 66 is disposed at a position corresponding to the connecting shaft 53, and is provided at a position near the restricting portion 48b of the shielding portion 48a. The side of the shielding portion 48a opposite to the protruding portion 65 is an abutting portion 67 that abuts on the second blade 49 of the second blade coupling body 42. The abutment portion 67 has one abutment portion 67a of the two second blades 48 and 49 having a concave shape, and a convex shape that fits into the concave shape is formed in the other abutment portion 67b. It is preferable to do. In this embodiment, as shown in FIGS. 17A and 17B, the second blade 48 of the first blade connector 41 is provided with a concave contact portion 67a, and the second blade of the second blade connector 42 is provided. 49 is provided with a convex contact portion 67b. Further, an inner alignment portion 68a for aligning with the second blade 49 is provided on one side of the contact portion 67b.

  Further, the restricting portion 48b of the second blade 48 includes an engaging recess 69 for positioning the second blade 48 at a predetermined position and an outer alignment portion for aligning the second blade 49. 68b and a restriction arm 71. The engagement recess 69 is a rectangular recess provided in the second blade 48. By engaging the engagement recess 69 with a reference position stopper provided in the barrier support plate 43, the second blade 48 is It is positioned at a substantially predetermined position in the closed position where the opening is closed. The outer alignment portion 68b has a role similar to that of the inner alignment portion 68a, and aligns the two second blades 48 and 49.

  The restricting arm 71 prevents the second blade 48 from rotating more than a predetermined amount with respect to the first blade 46 and entering inside, and a second blade stopper provided on the first blade 46. It is regulated by contacting with 55. At this time, the restriction of the rotation of the second blade 48 in the direction opposite to the rotation direction is executed by the first blade stopper 54 provided on the first blade 46. In addition, as a material of the 1st blade | wing 46 and the 2nd blade | wing 48 (the 1st blade | wing 47 and the 2nd blade | wing 49 are also the same), ABS (acrylonitrile butadiene styrene resin), POM (polyacetal) etc., for example However, it is also possible to use a metal such as stainless steel.

  The assembly operation of the first blade 46 and the second blade 48 having such a configuration (the same applies to the first blade 47 and the second blade 49) can be performed as follows, for example. . First, as shown in FIGS. 10 and 11, the connection shaft 53 of the first blade 46 is caused to face the connection hole 66 of the second blade 48, and the pair of retaining protrusions 53 a and 53 a of the connection shaft 53 are connected. It is made to oppose the slit 66b of the hole 66. FIG. In this state, the connecting shaft 53 having the pair of retaining protrusions 53a and 53a is inserted into the connecting hole 66 having the slit 66b. This state is the state shown in FIG. 12A.

  From this state, the first blade 46 is fixed and the second blade 48 is rotated approximately 90 degrees in the surface direction, and the pair of retaining protrusions 53a and 53a of the connecting shaft 53 are countersunk with the counterbore surface 66a of the connecting hole 66. Contact. This state is the state shown in FIG. 12B. When the second blade 48 is rotated, the first blade stopper 54 is positioned on the rotation locus, so that the second blade 48 is brought into contact with the first blade stopper 54. At this time, since the second blade 48 itself has a certain degree of elasticity or flexibility, it is possible to easily get over the first blade stopper 54 by elastically deforming the second blade 48.

  As a result, the two blades are rotatably connected in a state where the second blade 48 is stacked on the first blade 46, and the first blade connector 41 (the second blade connector 42 is also the same). Is configured. At this time, the second blade 48 is relatively rotatable with respect to the first blade 46 within the range shown in FIGS. 12B and 12C. That is, FIG. 12B shows a state in which half of the opening is closed by the first blade coupling body 41 (the same applies to the second blade coupling body 42), and the cutout portion 52 of the first blade 46 is the first. It is completely closed by two blades 48. At this time, since the restricting arm 71 of the second blade 48 is in contact with the second blade stopper 55 of the first blade 46, the second blade 48 cannot rotate further clockwise. .

  FIG. 12C shows a state in which the opening is completely opened. Since the second blade 48 is greatly rotated outward, the notch 52 of the first blade 46 is completely opened. ing. At this time, since the protruding portion 65 of the second blade 48 is in contact with the first blade stopper 54 of the first blade 46, the second blade 48 can be further rotated counterclockwise. Can not.

  The two sets of blade coupling bodies 41 and 42 assembled in this way are assembled so as to be rotatable at a predetermined position on one surface of the barrier support plate 43. As shown in FIGS. 8 and 9, the barrier support plate 43 is formed of a thin disc-like plate having an opening 51 having a substantially rectangular shape at the center. A notch 73 is provided for exposing the light emitting part. The openings 51 are portions (holes) through which light from the subject passes, and chamfered portions 51a are provided at the four corners. On one surface of the barrier support plate 43, a pair of pivots 74a and 74b for rotatably supporting the two sets of blade coupling bodies 41 and 42, and the two sets of blade coupling bodies 41 and 42 in the closed position. A reference position stopper 75 for positioning, a support shaft 76a, a plurality of restricting pins 76bb and 76c, and the like are provided.

  The pair of pivots 74a and 74b are arranged side by side so as to be parallel to one side of the opening 51, and a reference position stopper 75 is arranged in the vicinity of the substantially central portion of the side facing the pair of pivots 74a and 74b. The distance between the pair of pivot shafts 74a and 74b is such that the two boss portions 58 of the two first blades 46 and 47 are arranged when the two blade connection bodies 41 and 42 are arranged side by side so as to completely close the opening 51. , 58 are set to face each boss hole. At this time, the reference position stopper 75 is fitted in a rectangular space surrounded by the two engaging recesses 69 and 69 of the two sets of blade coupling bodies 41 and 42.

  Next, the coil spring 61 is stretched between the two spring receiving pins 62 and 62 of the two sets of blade coupling bodies 41 and 42 in a compressed state. By the spring force of the coil spring 61, the two first blades 46 and 47 are biased in the direction of pulling each other. That is, in FIG. 8, the first blade 46 of the first blade connector 41 is urged counterclockwise around the pivot 74a, and the first blade 47 of the second blade connector 42 is The pivot 74b is urged clockwise around the pivot 74b. As a result, the two second blades 48 and 49 are brought into contact with each other and the contact portions 67a and 67b are engaged with each other, so that entry of dust or the like can be reliably prevented.

  13-20 is a figure explaining the opening / closing operation | movement of 2 sets of blade | wing connection bodies 41 and 42 assembled as mentioned above. FIG. 13 is a diagram showing a state immediately before the two sets of blade coupling bodies 41 and 42 arranged symmetrically are brought into contact with each other. At this time, since the two first blades 46 and 47 are urged by the coil spring 61 in the direction of pulling each other, when the two first blades 46 and 47 approach each other, the first blades 46 and 47 Two second blades 48 and 49 having a rotation fulcrum on 47 move to a position approaching first. Then, as shown in FIG. 14, when the two contact portions 67a and 67b of the two second blades 48 and 49 start to hit, they are pressed against each other by the outer alignment portions 68b and 68b.

  As a result, the two second blades 48 and 49 rotate in opposite directions around the connection hole 66 fitted to the connection shaft 53. That is, the second blade 48 of the first blade coupling body 41 rotates clockwise with the connection hole 66 as the rotation center. On the other hand, the second blade 49 of the second blade connector 42 rotates counterclockwise around the connection hole 66 as a rotation center. Then, as shown in FIG. 15A, when substantially the entire two contact portions 67a and 67b of the two second blades 48 and 49 are in contact, the two second blades 48 and 49 are in a substantially parallel state. Become. As a result, the two first blades 46, 47 and the two second blades 48, 49 are combined to cover the entire opening 51, and the two blade connection bodies 41, 42 are pressed together. It will be stopped.

  Note that when the two sets of blade coupling bodies 41 and 42 are closed, the two first blades 46 and 47 are pressed against each other via the two second blades 48 and 49 and stopped. Therefore, for example, in FIG. 15A, if the two sets of blade coupling bodies 41, 42 are stopped at positions that are not equal to the left and right, the opening 51 cannot be covered, but in order to eliminate this, in this embodiment, A reference position stopper 75 is provided on the barrier support plate 43 so that the two sets of blade coupling bodies 41 and 42 are positioned substantially at the center.

  In this case, with respect to the reference position stopper 75, when the two first blades 46 and 47 stop when the two second blades 48 and 49 come into contact with each other, the two first blades 46 and 47 become the reference. As shown in FIG. 15B, the dimensions are set so as to have a clearance E so as not to hit the position stopper 75. With this configuration, the two second blades 48 and 49 can be surely brought into contact with each other while rotating the two first blades 46 and 47 to substantially the center.

  In the above, the case where the two second blades 48 and 49 abut first from the tip (tips of the two first blades 46 and 47) side has been described, but the two second blades 48 and 49 are described. However, the same applies to the case where the base (the pivots 74a and 74b) contacts first. FIG. 16 illustrates this state. When the two first blades 46 and 47 move in a direction approaching each other, the two second blades 48 and 49 rotate relatively in opposite directions. That is, the second blade 48 of the first blade connector 41 rotates counterclockwise around the connection hole 66 as a rotation center. On the other hand, the second blade 49 of the second blade coupling body 42 rotates clockwise around the connection hole 66 as a rotation center. Then, as shown in FIG. 15A, when substantially the entire two contact portions 67a and 67b of the two second blades 48 and 49 are in contact, the two second blades 48 and 49 are in a substantially parallel state. Become.

  FIG. 17A and FIG. 17B are diagrams for explaining the details of each blade when the two first blades 46 and 47 and the two second blades 48 and 49 are closed. As shown in FIG. 17A, after the two outer alignment portions 68b and 68b of the two second blades 48 and 49 start to turn and rotate, as shown in FIG. 17B, the two first blades 46 and 47 And the two second blades 48 and 49 are substantially parallel to each other, the two outer alignment portions 68b and 68b are in contact with each other, but the two contact portions 67a and 67b are provided with unevenness respectively. The portions (hereinafter referred to as “slope portions”) 77a and 77b that face each other depending on the shape are generated, and the slope portions 77a and 77b are not in contact but cover the opening 51.

  In addition, a similar state occurs in the abutting portions 56 of the two first blades 46 and 47, and the diagonally facing portions (hereinafter referred to as “slope portions”) 78a and 78b are opposed to each other. In the position where the second blades 48 and 49 collide and stop, the inclined surfaces 78a and 78b do not come into contact with each other. Therefore, even when the straight portions of the two contact portions 67a and 67b of the two second blades 48 and 49 are slightly bent or cannot be fully closed, the two contact portions 67a and 67b are substantially omitted. By abutting, as an effect of providing the slope portions 77a and 77b and the slope portions 78a and 78b, the lens can be made invisible directly, and the effect of covering the lens can be made more complete.

  FIG. 18 is a diagram illustrating an initial opening state when the opening 51 is opened by the two sets of blade coupling bodies 41 and 42. In the closed state before opening, as shown in FIG. 15, the two blade connecting bodies 41 and 42 are attracted by the spring force of the coil spring 61, and the opening 51 is completely closed. From this state, the two operation arms 59 and 59 of the two sets of blade coupling bodies 41 and 42 are simultaneously pressed by one operation pin 81. That is, the operating pin 81 is moved radially inward from the outer side of the barrier support plate 43, and the two operating arms 59 and 59 that overlap and cross each other against the spring force of the coil spring 61 are simultaneously subjected to the force F. Press to rotate.

  Accordingly, in FIG. 18, the coil spring 61 is extended, and the first blade 46 of the first blade coupling body 41 is indicated by a solid arrow with the boss portion 58 fitted to the pivot 54a as the rotation center. It rotates in the direction R1. At the same time, the first blade 47 of the second blade coupling body 42 rotates in the counterclockwise direction L1 indicated by the solid arrow with the boss portion 58 fitted to the pivot 54b as the rotation center. In this way, the two first blades 46 and 47 are opened simultaneously. At this time, the two second blades 48 and 49 are each rotationally displaced in an arbitrary posture as shown in the drawing until they come into contact with either the first blade stopper 54 or the second blade stopper 55.

  Thereafter, the two sets of blade coupling bodies 41 and 42 are largely rotated and displaced in accordance with the amount of movement of the operation pin 81, resulting in a state as shown in FIG. That is, the 1st blade | wing connection body 41 moves to one side of the left-right direction of the opening part 51, and moves to the position which does not block one side of the opening part 51. FIG. At the same time, the second blade coupling body 42 moves to the other side of the opening 51 in the left-right direction, and moves to a position where the other side of the opening 51 is not blocked. At this time, the two second blades 48 and 49 can be arranged in any posture with respect to the first blades 46 and 47, but due to the presence of the first blade stoppers 54 and 54 provided on the first blades 46 and 47. The restricting arms 71 and 71 of the second blades 48 and 49 do not come into contact with the restricting pins 76 c and 76 c for the second blades 48 and 49 provided on the barrier support plate 43.

  Further, when the operation pin 81 moves to the predetermined position, as shown in FIG. 20, the two sets of blade coupling bodies 41 and 42 move to the predetermined position, and the opening 51 is completely opened. . In this case, the two first blades 46 and 47 are retracted to a position where the operation pin 81 is completely opened by the force pressing the two operation arms 59 and 59, and the four corners of the opening 51 are the two second corners. It is completely exposed by the notches 52 and 52 provided in one blade 46 and 47. Further, the two second blades 48 and 49 rotatably supported by the two first blades 46 and 47 have a pair of restricting pins 76c provided on the barrier support plate 43 by the restricting portions 48b and 49b, respectively. , 76c. As a result, the two second blades 48 and 49 are rotationally displaced relative to the two first blades 46 and 47 and retreat to a position where the opening 51 is not covered.

  The regulation pin 76 b stops the first blade 46 via the second blade 48 by acting simultaneously with the regulation pin 76 c by stopping the rotating second blade 48. . The operations of the first blade 46 and the second blade 48 are the same in the second blade coupling body 42 in a mirror-symmetrical manner, but on the second blade coupling body 42 side, the regulation corresponding to the regulation pin 76b. The pin has been deleted. The reason for removing the restriction pin is that the second blade 49 in the second blade coupling body 42 is not necessarily required because it can be retracted so as not to cover the opening 51. is there.

  By the combination of the two sets of blade coupling bodies 41 and 42 and the coil spring 61 described above, the opening 51 provided in the barrier support plate 43 can be easily opened and closed. In addition, by moving one operation pin 81, a pair of operation arms 59, 59 stacked and crossing each other for an appropriate length are pressed to simultaneously open the four blades 46, 47, 48, 49. The opening 51 can be reliably opened by operating and retracting to the outside of the opening 51.

  A barrier support plate 43 to which two sets of blade coupling bodies 41 and 42 are attached is used by being attached to a case member 44 having a shape and configuration as shown in FIG. The case member 44 is formed of a housing having a recessed portion having a shape corresponding to the shape of the barrier support plate 43. The case member 44 has an end surface portion 44a having a round hole 84 corresponding to the lens and an arc portion on the outer peripheral edge of the end surface portion 44a. It has a circular arc side surface portion 44b provided so as to be continuously raised, and a straight side surface portion 44c provided so as to be continuously raised on a linear portion on the outer peripheral edge of the end surface portion 44a. A screw mounting portion 85 for screwing the case member 44 to the lens barrel 33 is provided on the straight side surface portion 44c.

  The round hole 84 provided in the end surface portion 44 a of the case member 44 has a size corresponding to the size of the objective lens 34, and when the four blades 46, 47, 48, 49 are opened, the opening 51 The entire size is set to be exposed. An interlocking operation mechanism 45 for automatically opening and closing the two pairs of blade coupling bodies 41 and 42 is attached to the case member 44. The interlocking operation mechanism 45 includes a swing lever 86 having an operation pin 81, a swing power unit 87 that swings the swing lever 86, and the like.

  The swing lever 86 is formed of a curved rod-shaped member having a configuration as shown in FIGS. 21A and 21B, and a boss portion 86a serving as a rotation center is provided in the middle portion in the longitudinal direction. A support shaft 76a provided on the barrier support plate 43 is rotatably fitted to the boss portion 86a. A swing lever 86 is rotatably supported by the barrier support plate 43 with the boss portion 86a fitted to the support shaft 76a as a center of rotation. An operation pin 81 is provided on one side in the longitudinal direction of the swing lever 86, and an input portion 86b for swinging the swing lever 86 is provided on the other side in the longitudinal direction. An operating force for swinging the swing lever 86 is input from the swing power unit 87 to the input unit 86b.

  As shown in FIGS. 24, 25, 26 A and B, the swing power unit 87 includes an electric motor 88 that is a power source, a cam gear 89 that swings the swing lever 86, and the power of the electric motor 88. A gear train 91 that is decelerated and transmitted to the cam gear 89 as rotational power, and a frame 92 that supports the gear train 91 and the like are provided. The frame 92 is made of a sheet metal member bent in a U-shape, and a cam gear 89 and a gear train 91 are supported at both ends between two bearing pieces 92a and 92a facing each other with a predetermined gap therebetween.

  The cam gear 89 includes a main part gear 93 provided with a plurality of teeth only in a part in the circumferential direction, a drive gear 94 provided integrally with one surface of the main part gear 93, and the other surface of the main part gear 93. And a cam pin 95 is provided. The cam pin 95 of the cam gear 89 is formed so as to protrude to the opposite side of the drive gear 94 at a position eccentric from the rotation center by a predetermined distance radially outward. The cam gear 89 is disposed on the front end side of the two bearing pieces 92a and 92a, and is supported at both ends by a first support shaft 96 penetrating between the two bearing pieces 92a and 92a. At this time, the cam pin 95 of the cam gear 89 is configured to pass through one bearing piece 92a to the outside and protrude downward by an appropriate length.

  The gear train 91 includes a worm gear 97, a worm wheel 98, an output gear 99, an intermediate large gear 101a, and an intermediate small gear 101b. The worm gear 97 is fixed to the rotating shaft of the electric motor 88 and is driven to rotate by the electric motor 88. A worm wheel 98 is engaged with the worm gear 97. The worm wheel 98 is disposed with respect to the worm gear 97 so as to have a predetermined interval between the central axes thereof and to extend in a direction orthogonal to each other. An output gear 99 is arranged so as to be concentric with the worm wheel 98, and the second support shaft 102 passes through both gears 98 and 99 and is integrally formed in the rotational direction.

  The worm wheel 98 and the output gear 99 are disposed on the fixed piece 92b side connecting the two bearing pieces 92a and 92a of the frame 92, and the second support shaft 102 supported at both ends by the both bearing pieces 92a and 92a. Is attached to the frame 92. The intermediate large gear 101a and the intermediate small gear 101b are overlapped with each other, and the third support shaft 103 passes through both the gears 101a and 101b and is integrally formed in the rotation direction. The third support shaft 103 is disposed between the first support shaft 96 and the second support shaft 102 and is supported at both ends by two bearing pieces 92a and 92a. In this state, the intermediate large gear 101 a is engaged with the output gear 99, and the intermediate small gear 101 b is engaged with the main gear 93 of the cam gear 89.

  The electric motor 88 is fixed to a fixed piece 92 b of the frame 92. A hole through which the worm gear 97 is inserted is opened in the fixed piece 92b, and movement of the worm gear 97 passing through the hole in the motor rotation axis direction is prevented by the restriction piece 92c. As shown in FIG. 5 and the like, the swing power unit 87 having such a configuration is a power storage unit provided on a surface opposite to the blade storage unit in which the four blades 46 to 49 of the case member 44 are stored. 105 is attached. The power storage portion 105 is sized to fit in a part of the ring-shaped end surface portion 44 a of the case member 44. The power storage portion 105 includes a recessed portion 105 a in which a part of one surface of the swing power portion 87 is stored, and a cam gear 89. A first through hole 105b is provided for allowing a part to penetrate.

  The recessed portion 105a of the power storage portion 105 is provided with an insertion hole 106a through which the shaft portion of the fixing screw is inserted. By tightening and fixing the frame 92 with a fixing screw inserted through the insertion hole 106 a, the swing power unit 87 is stored in the power storage unit 105 and is fixed to the case member 44. Further, the end surface portion 44a of the case member 44 is provided with a second through hole 107a for penetrating the operation pin 81 of the swing lever 86 and a third through hole 107b for penetrating the boss portion 86a. ing. The second through hole 107a is provided with a flange 108 for protecting the operation pin 81, and the operation pin 81 swings within a predetermined range in the radial direction of the end face portion 44a inside the flange 108. It is possible.

  As shown in FIGS. 23 to 25, the support shaft 76 a of the barrier support plate 43 is inserted into the third through hole 107 b of the case member 44. A boss 86a of a swing lever 86 is rotatably fitted to the support shaft 76a from the side opposite to the four blades 46 to 49, and the swing lever 86 swings around the support shaft 76a. Is done. Further, the input portion 86b of the swing lever 86 is inserted into the first through hole 105b, and comes into contact with the cam pin 95 of the cam gear 89 that can be rotated in the first through hole 105b. When the turning force of the cam pin 95 is transmitted to the input portion 86b, the swing lever 86 swings around the boss portion 86a.

  The operation of the swing power unit 87 having such a configuration is as follows, for example. As shown in FIG. 6, the case member 44 is assembled on a barrier support plate 43 in which four blades 46 to 49 are assembled, and is assembled using a fixing screw or a snap fit (not shown). Accordingly, the end surface portion 44a of the case member 44 is opposed to the barrier support plate 43 while holding a gap in which the two sets of blade coupling bodies 41 and 42 can move. Then, in the predetermined region surrounded by the arc side surface portion 44b and the straight side surface portion 44c of the case member 44, the two pairs of blade coupling bodies 41 and 42 can perform the opening / closing operation as described above.

  FIG. 23 shows the assembled state of the swing lever 86 as viewed from the side opposite to the side where the two sets of blade coupling bodies 41 and 42 are disposed. The swing lever 86 is rotatable about the support shaft 76a, and an operation pin 81 that simultaneously presses the two operation arms 59, 59 of the two pairs of blade coupling bodies 41, 42 has a second penetration. It penetrates the hole 107a and protrudes to the opposite surface side. Therefore, by pressing the opposite side of the swing lever 86 to the operation pin 81 to the radially outer side of the barrier support plate 43, the operation pin 81 is relatively moved radially inward. As a result, the operation pin 81 simultaneously presses the two operation arms 59 and 59, and as a result, the four blades 46 to 49 are moved in the direction of opening the opening 51.

  The swinging power source 87 automatically swings the swinging lever 86, and has a configuration as shown in FIGS. That is, the rotational speed is reduced by the worm gear 97 and the worm wheel 98 fixed to the rotating shaft of the electric motor 88, and then the cam pin 95 of the cam gear 89 is rotated through the reduction gear train. In this embodiment, teeth are formed in approximately half of the circumferential direction of the main gear 93, and the rotation angle of the cam gear 89 is set to approximately 180 degrees. Therefore, the cam pin 95 is rotatable within a range of about 180 degrees from the position shown in FIG. 26A to the position shown in FIG. 26B. The swing power unit 87 is attached to the case member 44 by a fixing member such as a fixing screw in the state shown in FIG.

  FIGS. 21A and 21B are diagrams for explaining the operation of the swing power unit 87, and show the relationship between the cam pin 95, the swing lever 86, and the blade opening / closing operation. When the cam pin 95 of the cam gear 89 is in a position as shown in FIG. 21A, the two operation arms 59, 59 of the two first blades 46, 47 are not pressed. 42 closes the entire opening 51 of the barrier support plate 43. From this state, when the electric motor 88 is driven and the cam pin 95 rotates 180 degrees in the clockwise direction indicated by the arrow, the state shown in FIG. 21B is obtained.

  At this time, since the input portion 86b of the swing lever 86 is pressed by the rotation of the cam pin 95, the swing lever 86 is rotated counterclockwise. Thereby, since the operation pin 81 presses the two operation arms 59 and 59 simultaneously, the two sets of blade coupling bodies 41 and 42 are simultaneously pushed in the left-right direction. On the other hand, when closing the opening 51, the electric motor 88 rotates in the opposite direction to that at the time of opening, and the cam pin 95 is rotated in the opposite direction. At this time, the swing lever 86 swings in the reverse direction, and the operation pin 81 moves in a direction to escape from the two operation arms 59 and 59. At the same time, the two sets of blade coupling bodies 41 and 42 are pulled back by the tensile force of the coil spring 61, and the entire opening 51 is closed.

  The opening / closing operation by the two sets of blade coupling bodies 41, 42 that open / close the opening 51 is detected by the opening / closing detection mechanism 110. As shown in FIGS. 24, 25, and 27, the open / close detection mechanism 110 includes a drive gear 94 provided in the cam gear 89, a slide member 111 having an internal tooth 111 a meshed with the drive gear 94, and the slide member The light-shielding protrusion 112 provided in 111 and two light-shielding sensors 113 and 114 for detecting the position of the light-shielding protrusion 112 are provided. The slide member 111 is composed of a rod-shaped member having a L-shaped cross-section having a radius of curvature similar to the inner peripheral surface of the arc side surface portion 44b of the case member 44, and a drive gear 94 is formed on a part of the inner surface thereof. Internal teeth 111a that are meshed with each other are formed.

  The number of the internal teeth 111a of the slide member 111 is a number required to ensure the meshing of the drive gear 94 that rotates 180 degrees. The slide member 111 is slidably supported by a plurality of guide pieces 115a and 115b provided on the inner surface of the arc side surface portion 44b. A stopper piece 116 that restricts the amount of movement of the slide member 111 is disposed on one side of the movement direction of the slide member 111. The stopper piece 116 and the plurality of guide pieces 115a and 115b are integrally provided on the inner surface of the arc side surface portion 44b. The light shielding protrusion 112 is formed so as to protrude on one side in a direction orthogonal to the direction in which the internal teeth 111a of the slide member 111 protrude.

  Two light shielding sensors 113 and 114 are provided corresponding to the light shielding protrusion 112. The two light shielding sensors 113 and 114 detect the open / closed state of the opening 51 by detecting the light shielding protrusion 112 and detecting the position of the slide member 111. The first light shielding sensor 113 detects the closed state of the opening 51, and the second light shielding sensor 114 detects the open state of the opening 51.

  In the state where the opening 51 is completely closed by the two sets of blade coupling bodies 41 and 42, the first light shielding sensor 113 has the light shielding protrusion 112 of the slide member 111 in which the internal gear 111 a meshes with the driving gear 94 at that time. Are arranged at corresponding positions. The second light shielding sensor 114 is arranged at a position corresponding to the light shielding protrusion 112 of the slide member 111 at that time in a state where the opening 51 is completely opened from the two sets of blade coupling bodies 41 and 42. Yes. As the light shielding sensors 113 and 114, for example, photonic sensors can be used.

  24 and 25 show a state in which the drive gear 94 is rotated by driving of the electric motor 88 of the swinging power unit 87 and the slide member 111 is moved between the open position and the closed position of the opening 51. . That is, FIG. 24 shows a state where the light-shielding protrusion 112 has moved to the open position, and at this time, the light-shielding protrusion 112 has moved to the position of the second light-shielding sensor 114. FIG. 25 shows a state where the light-shielding protrusion 112 has moved to the closed position. At this time, the light-shielding protrusion 112 has moved to the position of the first light-shielding sensor 113. As described above, since the position of the light shielding protrusion 112 corresponds to the positions of the two light shielding sensors 113 and 114, the light shielding protrusion 112 is detected when the light shielding protrusion 112 comes to these positions, so that the open mode and the closed state are detected. You can know the mode.

  3 and 4 show a state in which a cover 117 for fixing the slide member 111 of the open / close detection mechanism 110 and the two light shielding sensors 113 and 114 to the case member 44 is attached. The cover 117 is fastened and fixed to the case member 44 by a fixing screw 118. The range covered by the cover 117 may be in a range that can cover the gear and the slide member 111 manufactured relatively accurately.

  With the configuration as described above, the lens barrier can be switched between the open mode and the closed mode by driving the electric motor 88, and whether the mode is in the open state or the closed state is determined by the photonic sensor. This can be known by detecting the shading. And switching control can be automatically performed by performing control which stops electric motor 88 in each mode.

  As described above, according to the lens barrier mechanism of the present invention, it is possible to cover the opening with four blades by urging two sets of wing coupling bodies with one coil spring. For this reason, the structure of this type of lens barrier mechanism can be made very simple, and the entire mechanism can be reduced in size and weight, and it is advantageous for cost reduction. In addition, it is possible to perform an operation of opening the opening of the two sets of the wing coupling bodies covering the opening by simply pressing one of them, which is advantageous for downsizing and cost reduction. . Furthermore, since there is no large ring or sliding member in the entire mechanism, the dust-proof range can be reduced. From this point as well, the entire mechanism can be reduced in size, weight, and cost.

  The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, an example in which the present invention is applied to a digital video camera has been described as a specific example of the imaging apparatus. However, the imaging apparatus can be applied to an analog video camera, and may be an imaging apparatus having a lens barrier mechanism as described above. For example, the present invention can be applied to an electronic still camera, a mobile phone, a PHS, and various other imaging devices.

It is the perspective view seen from the front side which shows the 1st Example of the lens barrier mechanism of this invention with a lens apparatus and a decorative ring. It is the perspective view which looked at the lens barrier mechanism shown in FIG. 1 from the front side. FIG. 3 is a perspective view of the lens barrier mechanism shown in FIG. 2 as viewed from the back side, in a state where an opening is closed by two sets of blade coupling bodies. FIG. 3 is a perspective view of the lens barrier mechanism shown in FIG. 2 as viewed from the back side, in a state where two sets of blade coupling bodies are moved to open an opening. FIG. 3 is a perspective view of a state in which an open / close detection mechanism is removed from the lens barrier mechanism shown in FIG. 2. It is the perspective view which separated the case main body from the state shown in FIG. It is explanatory drawing explaining the relationship between 2 sets of blade | wing connection bodies, a rocking | fluctuation power part, and an opening-and-closing detection mechanism while attaching two sets of blade | wing connection bodies to a barrier support plate, and closing an opening part. It is explanatory drawing which shows the state which attached the 2 sets of blade | wing coupling bodies to the barrier support plate, and closed the opening part. It is explanatory drawing which isolate | separated two sets of blade | wing connection bodies from the state shown in FIG. It is a disassembled perspective view which shows the 1st Example of the blade | wing coupling body which concerns on the lens barrier mechanism of this invention. It is explanatory drawing which expands and shows the principal part of FIG. FIGS. 12A and 12B illustrate the operation of the first embodiment of the blade connection body according to the lens barrier mechanism of the present invention, FIG. 12A shows the initial assembly state, and FIG. 12B shows the notch portion of the first blade with the second blade. FIG. 12C is an explanatory diagram of the closed state and FIG. 12C in the state where the cutout portion of the first blade is opened by the second blade. FIG. 9 is an explanatory diagram illustrating a state immediately before the two second blades are in contact with each other, illustrating the operation of the two sets of blade connection bodies according to the lens barrier mechanism of the present invention. FIG. 7 is an explanatory diagram illustrating the operation of two sets of blade coupling bodies according to the lens barrier mechanism of the present invention, and illustrating a state immediately after the two second blades are in contact with each other. FIG. 15A illustrates a state in which the two second blades are in contact with each other, and FIG. 15B is an enlarged view of the main part of FIG. 15A. , Respectively. FIG. 6 is an explanatory diagram illustrating the operation of two sets of blade coupling bodies according to the lens barrier mechanism of the present invention, and illustrating a state immediately after two second blades are opened. FIG. 16A is an enlarged view for explaining the operation of FIG. 16, FIG. 16A shows a state immediately before the two second blades contact, and FIG. 16B shows a state immediately after the two second blades contact. , Respectively. It is explanatory drawing which shows the state which two sets of blade | wing coupling bodies further opened from the state of FIG. It is explanatory drawing which shows the state which two sets of blade | wing coupling bodies further opened from the state of FIG. FIG. 20 is an explanatory view showing a state where the two sets of blade coupling bodies are further opened from the state of FIG. 19 and the entire opening is opened. FIG. 21A is a diagram illustrating a swinging power unit according to the lens barrier mechanism of the present invention, in which FIG. 21A is a state in which the opening is closed, and FIG. 21B is a diagram illustrating a state in which the opening is open. It is explanatory drawing which expands and shows the principal part of FIG. 21B. It is explanatory drawing which expands and shows the principal part of FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an opening / closing operation mechanism according to a lens barrier mechanism of the present invention, and is an explanatory diagram in a state where an opening is opened. It is explanatory drawing of the state by which the opening / closing operation | movement mechanism which concerns on the lens barrier mechanism of this invention was demonstrated, and the opening part was closed. FIG. 26A is a diagram illustrating a state in which the cam gear is rotated in one direction, and FIG. 26B is a diagram illustrating a state in which the cam gear is rotated in the other direction. It is explanatory drawing explaining the opening / closing operation | movement mechanism which concerns on the lens barrier mechanism of this invention. 1 is a perspective view showing a first embodiment of an imaging apparatus using a lens barrier mechanism of the present invention, as viewed from the front side. 1 is a perspective view showing a first embodiment of an imaging apparatus using a lens barrier mechanism of the present invention, as viewed from the back side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Digital video camera (imaging device), 2 ... Exterior case, 3 ... Lens apparatus, 33 ... Lens barrel, 34 ... Objective lens, 37 ... Optical path hole, 38 ... Through-hole, 40 ... Lens barrier mechanism, 41, 42 ... blade connection body, 43 ... barrier support plate, 44 ... case member, 45 ... interlocking movement mechanism, 46, 47 ... first blade, 48, 49 ... second blade, 51 ... opening, 52 ... notch 54, 55 ... blade stopper, 56 ... contact portion, 59 ... operation arm, 61 ... coil spring (biasing member), 71 ... regulating arm, 75 ... reference position stopper, 86 ... swing lever, 86b ... input portion , 87: swinging power unit, 88: electric motor, 89: cam gear, 95: cam pin, 110: open / close detection mechanism, 111: slide member

Claims (7)

There are two sets of blade connections arranged in front of the objective lens directed to the subject and capable of opening and closing an opening through which light from the subject passes. A lens barrier mechanism comprising a first blade and a second blade movably connected,
The two first blades are rotatably supported by a pair of pivots provided on a barrier support plate having the opening and arranged at adjacent positions, and the two second blades are It is rotatably supported by the two first blades by a pair of connecting shafts provided on the side opposite to the pivot shaft and disposed at adjacent positions,
An interlocking operation of moving the two sets of blade coupling bodies in the vicinity of the pair of pivots of the two first blades between a closed position for closing the opening and an open position for opening the opening. A lens barrier mechanism characterized in that a portion is provided. The two sets of blade coupling bodies are arranged symmetrically so as to cover approximately half of the opening.
The barrier support plate is provided with a reference position stopper for positioning the two sets of blade coupling bodies at predetermined positions,
The lens barrier mechanism according to claim 1, further comprising an urging member that urges the two first blades toward the reference position stopper. The two second blades are disposed inside the two first blades,
In the closed position in which the opening is closed, the two second blades are brought into contact with each other to close a gap that cannot be closed by the two first blades,
In the open position where the opening is opened, the two second blades are brought into contact with a stopper portion provided on the barrier support plate or a member on the barrier support plate side, and are rotated so that the entire opening is covered. The lens barrier mechanism according to claim 1, wherein the lens barrier mechanism is opened.   3. The lens barrier mechanism according to claim 2, wherein the reference position stopper also serves as a reference position stopper for positioning the two second blades at a predetermined position. The interlocking operation unit includes a pair of operation arms that are provided on the two first blades and that overlap and protrude so as to cross each other.
The lens barrier mechanism according to claim 1, wherein the two pairs of blade coupling bodies are rotated in conjunction with the pair of operation arms as input portions. An interlocking drive mechanism is provided that presses the interlocking operation portion to rotate the two sets of blade coupling bodies.
The interlock drive mechanism includes a swing lever that is swingably supported by the barrier support plate and has an operation pin in contact with the interlock operation portion, and a swing power portion that swings the swing lever. The lens barrier mechanism according to claim 1, further comprising: There are two sets of blade connections arranged in front of the objective lens directed to the subject and capable of opening and closing an opening through which light from the subject passes. An imaging device comprising a lens barrier mechanism composed of a first blade and a second blade movably connected,
The lens barrier mechanism is
The two first blades are rotatably supported by a pair of pivots provided on a barrier support plate having the opening and arranged at adjacent positions, and the two second blades are It is rotatably supported by the two first blades by a pair of connecting shafts provided on the side opposite to the pivot shaft and disposed at adjacent positions,
An interlocking operation of moving the two sets of blade coupling bodies in the vicinity of the pair of pivots of the two first blades between a closed position for closing the opening and an open position for opening the opening. An imaging apparatus characterized by comprising a unit.

Images