JP2015203838A - Len barrel and optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism that attains reduction in size of a lens barrel and thinness thereof, and ensures high reliability so as to enable a necessary strength to be obtained even when a barrier blade receives an external force from a subject side.SOLUTION: A plurality of barrier blades 3 to 5 comprise: a subject side barrier blade 5 to be arranged on a subject side; and an imaging surface side barrier blade 4 that is arranged to be overlapped on the subject side barrier blade on an imaging surface side in an optical axis direction of the subject side barrier blade. On a tip side of the subject side barrier blade 5 of a rotating range reaching an opening location of the plurality of barrier blades 3 to 5 from a closing location thereof, in the rotating range where at least external force from the subject side causes a tip of the imaging side barrier blade to move in the optical axis direction, a falling regulation part 5c2 is provided that fits to a notch part 4b of the imaging surface side barrier blade 4 in the optical axis direction and regulates a movement to an optical axis direction imaging surface of the imaging surface barrier blade 4.

Description

  The present invention relates to a lens barrel on which a barrier mechanism is mounted, and an optical apparatus such as a digital camera including the lens barrel.

  Some optical devices such as digital cameras have a lens barrel mounted with a barrier mechanism that covers a lens exposed to the subject side through an opening of the barrier cover so that the lens can be opened and closed by a plurality of barrier blades. In addition, in order to reduce the storage area of the plurality of barrier blades in the open state in response to a request to reduce the diameter of the lens barrel accompanying the downsizing of the camera, the plurality of barrier blades are stacked in the optical axis direction in the open state to open the opening portion. It is performed to store in the outer position.

  By the way, when the user intentionally moves the barrier blade in the opening direction by hand or when an impact is applied to the barrier blade, the barrier blade moves from a predetermined position. In this case, since the opening of the barrier cover is substantially rectangular and has the longest diagonal length, there is almost no overlap between the barrier blade and the barrier cover. Thus, in a state where there is almost no overlap between the barrier blade and the barrier cover, the barrier blade may protrude from the opening to the subject side or fall into the lens barrel due to slight deformation of the parts.

  Therefore, a U-shaped hook portion is provided at the tip of the third barrier blade, and the third barrier blade is inserted in the opening / closing direction with respect to the U-shaped hook portion in the first barrier blade that follows the opening / closing direction. A technique has been proposed in which a notch that can be contacted is provided (Patent Document 1).

  In this proposal, when the plurality of barrier blades move in the opening direction, the notch portion of the first barrier blade is guided so as to contact the inside of the U-shaped hook portion of the third barrier blade. Further, in the closed state, the contact state is maintained in a state where the notch portion and the U-shaped hook portion are overlapped with each other in the optical axis direction, whereby an external force is applied from the subject side, for example, the barrier blade is pushed by the user. The necessary strength is ensured even when receiving.

JP 2012-042683 A

  However, in the above-mentioned Patent Document 1, in the state where the notch part is separated from the U-shaped hook part during the opening and closing of the plurality of barrier blades, and the notch part and the U-shaped hook part do not overlap in the optical axis direction, The U-shaped hook portion cannot restrict the movement of the notch portion in the optical axis direction. Therefore, when a forced external force is applied from the subject side by the user, the first barrier blade 3 and the third barrier blade are bent, and the gap in the optical axis direction between the barrier blades is widened, so that the notch However, there is a problem in that it is detached from the U-shaped hook portion in the closing direction.

  In this case, by increasing the thickness of each barrier blade, it becomes possible to suppress the deflection of each barrier blade due to an external force and prevent the notch from coming off from the U-shaped hook portion. When the thickness of the lens barrel is increased, it becomes a cause of hindering the thinning of the lens barrel in the optical axis direction.

  Therefore, the present invention ensures high reliability by realizing the required strength even when the barrier blade receives an external force from the subject side while realizing a reduction in the diameter and thickness of the lens barrel. The purpose is to provide a mechanism that can do this.

  In order to achieve the above object, the present invention provides a photographic optical system in which a subject light beam enters through an opening, and a proximal end side between an open position for opening the opening and a closed position for closing the opening. A lens barrel having a pair of a plurality of barrier blades rotatably provided around a rotation axis, wherein the plurality of barrier blades are a subject-side barrier blade disposed on a subject side and the subject side An image plane side barrier blade disposed on the subject side barrier blade on the image plane side in the optical axis direction of the barrier blade, and at the tip side of the subject side barrier blade, the plurality of barrier blades Of the rotation range from the closed position to the open position, at least in the rotation range in which the tip of the image plane side barrier blade moves in the optical axis direction by an external force from the subject side, with respect to the image plane side barrier blade The image plane side barrier blade engaged in the optical axis direction Wherein the dropping regulating portion for regulating the movement in the optical axis direction image surface side is provided.

  According to the present invention, the lens barrel can be reduced in diameter and thinned, and the required strength can be obtained even when the barrier blade receives an external force from the subject side to ensure high reliability. be able to.

It is the perspective view which looked at the digital camera as an example of the optical apparatus provided with the lens barrel which is the first embodiment of the present invention from the front side (subject side). It is a disassembled perspective view of the surrounding member of the barrier mechanism of a lens-barrel and a 1st group lens holding frame. It is the perspective view which looked at the barrier drive ring from the subject side. It is a perspective view of a barrier holding frame. (A) is the figure which looked at the closed state of the 1st barrier blade from the to-be-photographed object side, (b) is the figure which looked at the open state of the 1st barrier blade from the to-be-photographed object side. (A) is the figure which looked at the closed state of the barrier blade from the image plane side in the optical axis direction, (b) is the figure which looked at the open state of the barrier blade from the image plane side in the optical axis direction. It is the figure which looked at the state where one barrier blade of a pair of barrier blades was manually forcibly rotated to the open position from the image plane side in the optical axis direction in the closed state of the barrier blades. (A), (b), and (c) are the elements on larger scale of FIG. 6 (a), FIG.6 (b), and FIG. 7, respectively. It is a perspective view of FIG.8 (c). (A) is a figure which shows the positional relationship of the 2nd barrier blade of a normal state, and the 3rd barrier blade, (b) is the 2nd barrier when the position of the optical axis direction of a 3rd barrier blade has shifted | deviated. It is a figure which shows the positional relationship of a blade | wing and a 3rd barrier blade | wing. (A) is a perspective view when the second bent portion is not provided in the third barrier blade drop-out restricting portion, and (b) is the first bent portion of the third barrier blade drop-out restricting portion is dropped out. It is a perspective view which shows the state which got over the part. It is a perspective view which shows the modification of the drop-off control part of a 2nd barrier blade | wing. (A) is the perspective view which looked at each front-end | tip part in the closed state of several barrier blades from the image surface side, (b) The perspective view which looked at each front-end | tip part in the open state of several barrier blades from the image surface side. FIG. It is the figure which looked at the open state of the several barrier blade | wing from the image surface side of the optical axis direction. In the 2nd Embodiment of this invention, it is the perspective view which looked at the closed state of several barrier blade | wings from the to-be-photographed object side. It is the figure which looked at the closed state of several barrier blade | wings from the image surface side of the optical axis direction. It is the side view which looked at the closed state of a plurality of barrier blades from the direction which intersects perpendicularly with an optical axis. It is the perspective view which looked at the 2nd barrier blade and the 3rd barrier blade from the image side. (A) is the figure which looked at the closed state of the 2nd barrier blade and the 3rd barrier blade from the image plane side of the optical axis direction, (b) is the opening of the 2nd barrier blade and the 3rd barrier blade. It is the figure which looked at the state from the image surface side of the optical axis direction. (A) is the perspective view which looked at the closed state of several barrier blades from the image surface side, (b) is the perspective view which looked at the open state of several barrier blades from the image surface side.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view of a digital camera as an example of an optical apparatus including a lens barrel that is a first embodiment of the present invention, as viewed from the front side (subject side).

  As shown in FIG. 1, the digital camera 100 of this embodiment is provided with a lens barrel 110, a strobe light emission window 104, and the like on the front side of the camera body 101. A power button 102, a release button 103, a zoom lever 107, and the like are provided on the upper surface of the camera body 101. An image sensor such as a CCD sensor or a CMOS sensor that photoelectrically converts a subject image that has passed through the photographing optical system of the lens barrel 110 is mounted inside the camera body 101.

  FIG. 2 is an exploded perspective view of the barrier mechanism of the lens barrel 110 and members around the first group lens holding frame 8.

  As shown in FIG. 2, the lens barrel 110 includes a barrier holding frame 1, a first lens holding frame 8, a cam barrel 10, a barrier driving ring 2, a plurality of barrier blades 3 to 5, a biasing member 6, and a barrier cover. 7 is provided.

  A first lens holding frame 8 that holds the first lens 9 is provided on the inner peripheral side of the barrier holding frame 1. A cam cylinder 10 is provided on the inner peripheral side of the first lens holding frame 8. A follower pin 11 is provided on the outer peripheral portion of the first lens holding frame 8 on the image plane side, and the follower pin 11 engages with a cam groove 10 a formed in the cam cylinder 10.

  Further, a follower pin 12 is provided on the outer peripheral portion of the end of the barrier holding frame 1 on the image plane side, and the follower pin 12 engages with a cam groove 10 b formed in the cam cylinder 10. A cam wall 10c with which a follower arm 2a (see FIG. 3), which will be described later, of the barrier drive ring 2 abuts is provided at the end of the cam cylinder 10 on the subject side.

  When the cam cylinder 10 is rotationally driven by a zoom motor (not shown), the follower pins 11 and 12 follow the cam grooves 10 a and 10 b so that the first lens holding frame 8 and the barrier holding frame 1 are in relation to the cam cylinder 10. Move relatively in the optical axis direction. Thereby, the drawing operation and the drawing operation of the lens barrel 110 are performed.

  The plurality of barrier blades 3 to 5 include a first barrier blade 3 made of resin, a second barrier blade 4 made of metal, and a third barrier blade 5 made of metal. By making the second barrier blade 4 and the third barrier blade 5 made of metal, the barrier mechanism and the lens barrel 110 can be made thinner than those made of resin. Here, the third barrier blade 5 corresponds to an example of the subject side barrier blade of the present invention, and the second barrier blade 4 corresponds to an example of the image surface side barrier blade of the present invention.

  A pair of the first barrier blade 3, the second barrier blade 4, the third barrier blade 5, and the urging member 6 are arranged symmetrically with respect to the optical axis of the first lens 9. In this embodiment, the urging member 6 is constituted by a tension coil spring. The first barrier blade 3, the second barrier blade 4, and the third barrier blade 5 are supported so as to be rotatable in an opening / closing direction orthogonal to the optical axis, and the lens barrel 110 is retracted to the retracted position. Is closed, and the lens barrel 110 is opened to the shooting position (FIG. 1).

  The barrier cover 7 is disposed on the most object side of the lens barrel 110 and is fixed to the barrier holding frame 1 to protect the barrier blades 3 to 5. In addition, an opening 7 a is formed at the center of the barrier cover 7 so as not to block the subject luminous flux incident on the image sensor via the first lens 9.

  FIG. 3 is a perspective view of the barrier drive ring 2 as viewed from the subject side. The barrier drive ring 2 is rotatably held with respect to the barrier holding frame 1. As shown in FIG. 3, a follower arm 2 a is provided on the outer peripheral portion of the barrier drive ring 2 so as to extend toward the image plane side in the optical axis direction and have a tip portion formed in a slope shape. The follower arm 2a contacts the cam wall 10c (see FIG. 2) provided in the cam barrel 10 when the lens barrel 110 is retracted. When the cam cylinder 10 is rotated, the barrier drive ring 2 is rotated by the cam action of the cam wall 10c and the follower arm 2a.

  Further, a plurality of extending portions 2 b extending toward the image plane side in the optical axis direction are provided on the outer peripheral portion of the barrier drive ring 2 at a predetermined interval in the circumferential direction. Further, on the outer peripheral portion of the barrier drive ring 2, a shaft 2 c for hooking the end of the urging member 6 and an abutting portion 2 e for driving the first barrier blade 3 are provided.

  FIG. 4 is a perspective view of the barrier holding frame 1. As shown in FIG. 4, the barrier holding frame 1 has an arc hole 1 a (see FIG. 5) through which the follower arm 2 a provided in the barrier drive ring 2 passes, and an extension that guides the sliding of the barrier drive ring 2. Part 1b is provided. The outer peripheral portion of the extending portion 2 b of the barrier drive ring 2 slides in the rotational direction along the extending portion 1 b provided on the inner peripheral portion of the barrier holding frame 1. Further, the barrier holding frame 1 has a hole 1c through which a rotation shaft provided at the base end portion of the first barrier blade 3 is inserted, and a rotation provided at the base end portion of the third barrier blade 5. A shaft 1e through which the hole is inserted is provided.

  5A is a view of the closed state of the first barrier blade 3 as viewed from the subject side in the optical axis direction, and FIG. 5B is a view of the open state of the first barrier blade 3 from the subject side in the optical axis direction. FIG. In FIG. 5, the second barrier blade 4 and the third barrier blade 5 are not shown.

  Referring to FIG. 5, the first barrier blade 3 is provided with a shaft 3a (see FIG. 6) protruding toward the image plane side in the optical axis direction and a shaft 3b protruding toward the subject side in the optical axis direction. The shaft 3a is inserted into a hole 1c formed in the barrier holding frame 1, whereby the first barrier blade 3 is supported so as to be rotatable in the opening / closing direction about the shaft 3a.

  Further, in the vicinity of the shaft 3a of the first barrier blade 3, a protruding portion 3c and a spring hook portion 3d are provided. One end of the urging member 6 is hooked to the spring hook 3d, and the other end of the urging member 6 is hooked to the shaft 2c of the barrier drive ring 2. The spring hooking portion 3d is disposed at a position closer to the center of the optical axis than the shaft 3b, whereby the barrier driving ring 2 is attached in the clockwise direction (closed direction) in FIG. 5 by the biasing force of the biasing member 6. Be forced.

  A long hole 3e that is long in the opening and closing direction is formed on the outer peripheral side of the first barrier blade 3 in the opening and closing direction. Here, among the inner walls of the long hole 3e, the inner wall on the closing direction side is referred to as a first wall portion 3e1, and the inner wall on the opening direction side is referred to as a second wall portion 3e2.

  Next, the rotation operation of the first barrier blade 3 from the closed position to the open position will be described. When the first barrier blade 3 is in the closed position shown in FIG. 5A, the follower arm 2a of the barrier drive ring 2 and the cam wall 10c of the cam cylinder 10 are in contact with each other. As the cam cylinder 10 rotates, the cam action of the follower arm 2a and the cam wall 10c causes the barrier drive ring 2 to rotate in the clockwise direction in the figure, and the abutment portion 2e becomes a protrusion of the first barrier blade 3. The part 3c is pressed in the rotation direction.

  As the barrier drive ring 2 further rotates in the clockwise direction, the first barrier blade 3 rotates about the shaft 3a in the counterclockwise direction (opening direction) in the figure, and the contact portion 3f. Comes into contact with a stopper 1 h provided on the barrier holding frame 1. Thereby, the rotation of the first barrier blade 3 in the opening direction is restricted and stops at the open position shown in FIG.

  On the other hand, when the first barrier blade 3 is shifted from the open position to the closed position, the cam cylinder 10 rotates in the opposite direction to that described above, so that the barrier drive ring 2 is rotated counterclockwise in the figure. Driven by rotation. At this time, the abutting portion 2e of the barrier drive ring 2 tends to be separated from the protruding portion 3c of the first barrier blade 3, but the protruding portion 3c contacts the abutting portion 2e by the urging force of the urging member 6. It turns in the direction of contact.

  In other words, the first barrier blade 3 rotates about the shaft 3a in the clockwise direction (closed direction) in the drawing, and the mating portions 3g inside the opening / closing direction of the pair of first barrier blades 3 This abuts, thereby restricting the rotation of the first barrier blade 3. In addition, in order to increase the urging force of the urging member 6 when the barrier blades 3 to 5 are rotated from the closed position to the open position, the barrier drive ring 2 is provided with the respective matching portions 3g of the pair of first barrier blades 3. After contacting each other, it stops at a position further rotated counterclockwise in the figure (see FIG. 5A).

  Next, the opening / closing operation of the barrier blades 3 to 5 will be described with reference to FIGS.

  6A is a view of the closed state of the barrier blades 3 to 5 as viewed from the image plane side in the optical axis direction, and FIG. 6B is a view of the open state of the barrier blades 3 to 5 from the image plane side in the optical axis direction. FIG. FIG. 7 shows that in the closed state of the barrier blades 3 to 5 shown in FIG. 6 (a), one barrier blade 3 to 5 of the pair of barrier blades 3 to 5 is manually and manually rotated to the open position. It is the figure which looked at the moved state from the image surface side of the optical axis direction.

  FIGS. 8A, 8B, and 8C are partially enlarged views of FIGS. 6A, 6B, and 7, respectively. FIG. 9 is a perspective view of FIG. FIG. 10A is a diagram showing a positional relationship between the second barrier blade 4 and the third barrier blade 5 in a normal state, and FIG. 10B is a shift of the position of the third barrier blade 5 in the optical axis direction. It is a figure which shows the positional relationship of the 2nd barrier blade | wing 4 and the 3rd barrier blade | wing 5 at the time of a case. 8 to 10, the first barrier blade 3 is not shown.

  A shaft 3b (see FIG. 5) of the first barrier blade 3 is fitted into a hole 4e (see FIG. 18) formed in the base end portion of the second barrier blade 4. Thereby, the 2nd barrier blade | wing 4 is supported so that rotation in the opening / closing direction centering on the axis | shaft 3b is possible. As shown in FIGS. 6 and 7, the second barrier blade 4 is provided with a hook-shaped restricting portion 4 a that is inserted into the elongated hole 3 e of the first barrier blade 3.

  When the first barrier blade 3 rotates in the opening direction, the first wall portion 3e1 of the elongated hole 3e contacts the restricting portion 4a, and when the first barrier blade 3 rotates in the closing direction, the restricting portion. The second wall 3e2 of the long hole 3e comes into contact with 4a. As a result, the second barrier blade 4 can follow the opening / closing direction with respect to the first barrier blade 3. Further, the second barrier blade 4 is provided with a notch portion 4b and a contact portion 4c for moving the third barrier blade 5 in the opening / closing direction.

  The shaft 1 e of the barrier holding frame 1 is fitted into the hole 5 a formed in the base end portion of the third barrier blade 5. Thereby, the 3rd barrier blade | wing 5 is supported by the shaft 1e center so that rotation in the opening / closing direction is possible. A hook portion 5 c is formed at the tip of the third barrier blade 5.

  The hook portion 5c is bent approximately 90 ° toward the image plane side and then further bent 90 ° toward the inner side to form a substantially U-shape. Further, a bent portion 5b that is bent toward the image plane side is formed on the outer peripheral side of the third barrier blade 5 in the opening / closing direction. When the second barrier blade 4 rotates in the opening / closing direction, the bent portion 5b and the hook portion 5c of the third barrier blade 5 are in contact with the contact portion 4c and the notch portion 4b of the second barrier blade 4 in the opening / closing direction. Abut. As a result, the third barrier blade 5 can follow the opening / closing direction with respect to the second barrier blade 4.

  Next, the rotation operation of the barrier blades 3 to 5 from the closed position to the open position will be described. After the first barrier blade 3 starts rotating in the clockwise direction (opening direction) from the closed state shown in FIG. 6A, the first wall portion of the long hole 3e of the first barrier blade 3 is used. 3 e 1 abuts against the restriction portion 4 a of the second barrier blade 4. Further, when the first barrier blade 3 rotates in the opening direction, the first wall portion 3e1 pushes the restricting portion 4a in the opening direction, so that the second barrier blade 4 opens integrally with the first barrier blade 3. Rotate in the direction.

  When the first barrier blade 3 and the second barrier blade 4 are further rotated in the opening direction, the contact portion 4 c of the second barrier blade 4 contacts the bent portion 5 b of the third barrier blade 5. Thereafter, the abutting portion 4c pushes the bent portion 5b in the opening direction, so that the third barrier blade 5 rotates integrally with the first barrier blade 3 and the second barrier blade 4 in the opening direction.

  When the barrier blades 3 to 5 rotate in the opening direction and the contact portion 3f of the first barrier blade 3 contacts the stopper 1h of the barrier holding frame 1 and the rotation stops, the second barrier blade 4 that is driven follows. And the rotation of the third barrier blade 5 also stops. Thereby, it will be in the open state of the barrier blade | wings 3-5 shown to FIG.6 (b) and FIG.8 (b).

  On the other hand, when the barrier blades 3 to 5 are rotated from the open position to the closed position, the first barrier blade 3 rotates in the counterclockwise direction (closed direction) from the open state shown in FIG. After the start, the second wall 3e2 of the long hole 3e of the first barrier blade 3 comes into contact with the restricting portion 4a of the second barrier blade 4. Further, when the first barrier blade 3 rotates in the closing direction, the second wall portion 3e2 pushes the restricting portion 4a in the closing direction, so that the second barrier blade 4 is closed integrally with the first barrier blade 3. Rotate in the direction.

  When the first barrier blade 3 and the second barrier blade 4 are further rotated in the closing direction, the notch portion 4 b of the second barrier blade 4 comes into contact with the hook portion 5 c of the third barrier blade 5. Further, when the first barrier blade 3 and the second barrier blade 4 rotate in the closing direction, the notch portion 4b pushes the hook portion 5c in the closing direction, so that the third barrier blade 5 becomes the first barrier blade. 3 and the second barrier blade 4 rotate together in the closing direction.

  When the barrier blades 3 to 5 rotate in the closing direction and the mating portions 3g of the pair of first barrier blades 3 come into contact with each other and the rotation of the first barrier blade 3 stops, the second barrier blade that is driven 4 and the third barrier blade 5 also stop rotating. As described above, the barrier drive ring 2 stops at a position further rotated from the rotation stop position of the first barrier blade 3. Thereby, the barrier blades 3 to 5 shown in FIGS. 6A and 8A are closed.

  Next, a case where the user forcibly opens the barrier blades 3 to 5 in the closed state of the barrier blades 3 to 5 shown in FIG. 6A will be described.

  As described above, in the closed state of the first barrier blade 3, after the pair of first barrier blades 3 contact each other, the barrier drive ring 2 further rotates in the closing direction and then stops. That is, in the closed state of the first barrier blade 3, the protrusion 3c of the first barrier blade 3 does not contact the contact portion 2e of the barrier drive ring 2, as shown in FIG. It is urged in the closing direction by the urging member 6.

  As shown in FIG. 7, when the upper barrier blades 3 to 5 are forcibly pushed in the opening direction by a user's hand or the like, the upper first barrier blade 3 is closed by the biasing force of the biasing member 6. It tries to rotate further in the closing direction. When the lower first barrier blade 3 rotates in the closing direction, the lower second barrier blade 4 and the upper third barrier blade 5 are also changed to the upper first barrier blade 3 as described above. Followed to rotate integrally in the closing direction.

  Then, after the upper barrier blades 3 to 5 are rotated in the closing direction by a predetermined amount, as shown in FIGS. 8C and 9, the drop-off restricting portion 4 d provided on the lower second barrier blade 4 The drop-off restricting portion 5d provided on the upper third barrier blade 5 abuts. Thereby, the rotation of the upper barrier blades 3 to 5 in the closing direction is restricted, and the third barrier blade 5 jumps out from the opening 7 a to the subject side, or the first barrier blade 3 enters the lens barrel 110. It can prevent being depressed.

  In the present embodiment, the case where the user forcibly opens the barrier blades 3 to 5 is illustrated, but the present invention is not limited to this. For example, when the pair of barrier blades are closed, the barrier blade on one side may not be closed due to the inclusion of a foreign substance, or when an impact or the like is applied during the closing of the barrier blade.

  In the present embodiment, in order to make the lens barrel 110 thinner, the second barrier blade 4 and the third barrier blade 5 are made of thin metal plates. In order to smoothly open and close the barrier blades 3 to 5, it is desirable that the barrier blades 3 to 5 have a certain gap in the optical axis direction between the barrier drive ring 2 and the barrier cover 7.

  On the other hand, by providing a certain gap, the height of the barrier blades 3 to 5 in the optical axis direction may be slightly shifted. Considering that the heights of the second barrier blade 4 and the third barrier blade 5 in the optical axis direction are shifted in this way, in this embodiment, the drop-off restricting portion 4 d is the base end of the second barrier blade 4. It is formed by bending the side toward the subject side in the optical axis direction. The drop-off restricting portion 5d is formed by bending the tip side of the third barrier blade 5 toward the image plane side in the optical axis direction.

  Specifically, the drop-off restricting portion 4d is formed by bending the proximal end side of the second barrier blade 4 toward the subject side at an angle of approximately 90 °. The drop-off restricting portion 5d includes a first bent portion 5d1 formed by bending the tip side of the third barrier blade 5 toward the image plane side by approximately 90 °, and approximately 90 ° inward from the tip of the first bent portion 5d1. It has the 2nd bending part 5d2 formed by bending, and is formed in a substantially U shape.

  By forming the drop-off restricting portions 4d and 5d in this manner, even when the heights of the second barrier blade 4 and the third barrier blade 5 in the optical axis direction are shifted as shown in FIG. It is possible to maintain the contact state between the portion 4d and the drop-off restricting portion 5d.

  Next, a case where the heights of the second barrier blade 4 and the third barrier blade 5 in the optical axis direction are significantly shifted will be described with reference to FIG. FIG. 11A is a perspective view when the second bent portion 5d2 is not provided in the drop-out restricting portion 5d shown in FIG. 9, and FIG. 11B is a view showing that the first bent portion 5d1 of the drop-out restricting portion 5d is dropped. It is a perspective view which shows the state which got over the part 4d.

  When the height of the second barrier blade 4 and the third barrier blade 5 in the optical axis direction is significantly shifted due to impact or the like, the first bent portion 5d1 of the drop-out restricting portion 5d may get over the drop-out restricting portion 4d. is there. In this case, as shown in FIG. 11 (a), if the second bent portion 5d2 is not provided in the drop-out restricting portion 5d, the drop-out restricting portions 4d and 5d are fitted to each other as shown in FIG. 11 (b). Accordingly, even if the user tries to restore it, it cannot be restored.

  On the other hand, in the present embodiment, as described above, the drop-off restricting portion 5d of the third barrier blade 5 is provided with the second bent portion 5d2 so that the drop-off restricting portion 5d is substantially U-shaped. Even when the restricting part 5d gets over the drop-off restricting part 4d, they do not fit each other. That is, even if the drop-out restricting portion 5d gets over the drop-out restricting portion 4d, the user can easily return to the original state manually.

  In the present embodiment, the drop-out restricting portion 5d of the third barrier blade 5 is U-shaped, but the drop-out restricting portion 4d of the second barrier blade 4 may be U-shaped, and both The drop-out restricting portions 4d and 5d may be U-shaped.

  In the present embodiment, the case where the drop-off restricting portion 4d and the drop-off restricting portion 5d are formed on the second barrier blade 4 and the third barrier blade 5, respectively, is illustrated, but the combination of barrier blades that form the drop-off restricting portion The bending direction is not particularly limited.

  In the present embodiment, the drop-off restricting portion 4d is formed by being bent toward the subject side in the optical axis direction, and the drop-off restricting portion 5d is formed by the first bent portion 5d1 and the second bent portion 5d2. However, the present invention is not limited to this.

  For example, as shown in FIG. 12, the drop-off restricting portion 4 d of the second barrier blade 4 is bent to the subject side in the optical axis direction, and then bent outward to the same height as the flat portion of the third barrier blade 5. Further, it may be formed by being bent toward the image surface side. In this case, even if the second bending part 5d2 is not provided in the drop-off restricting part 5d, the tips of the drop-off restricting parts 4d and 5d are both bent toward the image plane side, so that the drop-off restricting parts 4d and 5d do not get over each other. .

  Further, as shown in FIG. 8B, in the opened state of the barrier blades 3 to 5, the position where the distance from the optical axis center is the largest is the outer peripheral portion 5 e of the third barrier blade 5, and the barrier cover 7. Is determined by the outer peripheral portion 5 e of the third barrier blade 5. As shown in FIG. 8, the movement trajectories of the drop-out restricting portion 4 d of the second barrier blade 4 and the drop-out restricting portion 5 d of the third barrier blade 5 have diameters determined by the outer peripheral portion 5 e of the third barrier blade 5. It is inside. For this reason, the diameter of the lens barrel 110 is not increased by providing the drop-out restricting portion 4d of the second barrier blade 4 and the drop-out restricting portion 5d of the third barrier blade 5.

  Next, referring to FIG. 13 and FIG. 14, the relationship between the hook portion 5 c provided on the tip side of the third barrier blade 5 and the notch portion 4 b provided on the tip side of the second barrier blade 4. Is further described in detail.

  FIG. 13A is a perspective view of the tip portions of the barrier blades 3 to 5 in the closed state as viewed from the image plane side, and FIG. 13B illustrates the tip portions of the barrier blades 3 to 5 in the open state. It is the perspective view seen from the surface side. FIG. 14 is a view of the opened state of the barrier blades 3 to 5 as viewed from the image plane side in the optical axis direction.

  As shown in FIG. 13, the hook portion 5c provided on the distal end side of the third barrier blade 5 is a contact portion 5c1 bent 90 ° toward the image plane side, and is bent 90 ° further inward from the contact portion 5c1. The drop-off restricting portion 5c2 is formed in a substantially U shape. As described above, the notch portion 4b of the second barrier blade 4 contacts the contact portion 5c1 in the opening / closing direction. The contact portion 4c and the notch portion 4b of the second barrier blade 4 are in contact with the bent portion 5b and the contact portion 5c1 of the third barrier blade 5, respectively, so that the third barrier blade 5 is in the second state. The barrier blade 4 can be moved in the opening / closing direction.

  The drop-off restricting portion 5c2 is configured such that the notch portion 4b of the second barrier blade 4 is between the closed position of the barrier blades 3 to 5 shown in FIG. 13 (a) and the open position shown in FIG. 13 (b) and FIG. The notch 4b is engaged with the notch 4b within the range of relative movement to restrict the notch 4b from moving toward the image plane side in the optical axis direction.

  The drop-off restricting portion 5c2 causes the second barrier blade 4 to be deformed by pushing the second barrier blade 4 with an external force from the subject side by the user, and then the second barrier blade 4 is moved with respect to the third barrier blade 5. Even if it is rotated in the closing direction, the movement of the notch 4b toward the image plane side in the optical axis direction is restricted. For this reason, it can prevent that the notch part 4b remove | deviates from the hook part 5c. As a result, it is not necessary to increase the thickness of the second barrier blade 4 to increase the strength so that the notch 4b does not come off the hook 5c with respect to the external force from the subject side by the user, and the lens barrel 110 is thin. Can be achieved.

  Further, by disposing the drop-off restricting portion 5c2 of the hook portion 5c at a position on the distal end side away from the hole 5a that is the rotation center on the proximal end side of the third barrier blade 5, deformation due to external force from the subject side is caused. It is possible to regulate the deformation of the largest tip side portion.

  Further, as shown in FIG. 14, the drop-off restricting portion 5c2 is disposed outside the turning radius R1 at the tip of the first barrier blade 3, and as shown in FIG. 13, the first barrier blade 3 and the optical axis direction It is arranged so as not to overlap. For this reason, even if the drop-off restricting portion 5c2 is provided, the thickness of the lens barrel 110 does not increase.

  As described above, in the present embodiment, the lens barrel 110 can be reduced in diameter and thinned, and the second barrier blade 4 can obtain necessary strength even when receiving external force from the subject side. Therefore, high reliability can be ensured.

(Second Embodiment)
Next, a digital camera as an example of an optical apparatus including a lens barrel that is a second embodiment of the present invention will be described with reference to FIGS. 15 to 20. Note that portions that overlap or correspond to the first embodiment will be described with the same reference numerals attached to the respective drawings.

  FIG. 15 is a perspective view of the closed state of the barrier blades 3 to 5 as viewed from the subject side. FIG. 16 is a view of the closed state of the barrier blades 3 to 5 as viewed from the image plane side in the optical axis direction. FIG. 17 is a side view of the closed state of the barrier blades 3 to 5 as viewed from the direction orthogonal to the optical axis.

  In the said 1st Embodiment, the optical axis direction image surface side of the notch part 4b in the range to which the notch part 4b of the 2nd barrier blade 4 moves relatively between the closed position of the barrier blades 3-5, and an open position. A hooking part 5c2 is provided integrally with the contact part 5c1 to constitute the hook part 5c. On the other hand, in this embodiment, as shown in FIGS. 15 to 17, the drop-off restricting portion 5 f is provided integrally with the hook portion 5 f separate from the contact portion 5 c 1, and the image plane direction image surface of the notch portion 4 b. The movement to the side is regulated.

  FIG. 18 is a perspective view of the second barrier blade 4 and the third barrier blade 5 as seen from the image plane side. 19A is a view of the closed state of the second barrier blade 4 and the third barrier blade 5 as viewed from the image plane side in the optical axis direction, and FIG. 19B is the second barrier blade 4 and It is the figure which looked at the open state of the 3rd barrier blade | wing 5 from the image surface side of the optical axis direction. 20A is a perspective view of the closed state of the barrier blades 3 to 5 as viewed from the image plane side, and FIG. 20B is a view of the open state of the barrier blades 3 to 5 as viewed from the image plane side.

  As shown in FIGS. 18 to 20, the notch portion 4b of the second barrier blade 4 abuts in the opening / closing direction on the abutting portion 5c1 as in the first embodiment. The contact portion 4c and the notch portion 4b of the second barrier blade 4 are in contact with the bent portion 5b and the contact portion 5c1 of the third barrier blade 5, respectively, so that the third barrier blade 5 is in the second state. The barrier blade 4 can be moved in the opening / closing direction.

  At the distal end portion of the third barrier blade 5, a hook portion 5f is formed on the proximal end side of the contact portion 5c1. The hook portion 5f has a bent portion 5f1 bent approximately 90 ° on the image plane side and a drop-out restricting portion 5f2 bent 90 ° further inward from the bent portion 5f1 and is formed in a substantially U-shape.

  The drop-off restricting portion 5f2 has a second position between the closed position shown in FIGS. 19 (a) and 20 (a) and the open position shown in FIGS. 19 (b) and 20 (b). The notch 4b of the barrier blade 4 engages with the notch 4b in the optical axis direction within a range in which the notch 4b moves relatively. As a result, the movement of the notch 4b toward the image plane side in the optical axis direction is restricted. Further, the drop-off restricting portion 5f2 is provided separately from the contact portion 5c1, and thus is continuously provided to the bent portion 5f1 provided at the outer peripheral portion in the opening / closing direction on the tip side of the third barrier blade 5.

  After the second barrier blade 4 is pushed by the external force from the subject side by the user to deform the cutout portion 4b by the drop-off regulating portion 5f2, the second barrier blade 4 is moved with respect to the third barrier blade 5. Even if it is rotated in the closing direction, the movement of the notch 4b toward the image plane side in the optical axis direction is restricted. For this reason, it can prevent that the notch part 4b remove | deviates from the hook part 5f. As a result, it is not necessary to increase the thickness of the second barrier blade 4 to increase the strength so that the notch portion 4b does not come off the hook portion 5f due to the external force from the subject side by the user, and the lens barrel 110 is thin. Can be achieved.

  Further, as shown in FIG. 16, the drop-off restricting portion 5f2 is disposed outside the turning radius R1 of the tip portion of the first barrier blade 3, and as shown in FIG. Arranged so as not to overlap in the axial direction. For this reason, the thickness of the lens barrel 110 does not increase even if the drop-off restricting portion 5f2 is provided.

  Furthermore, in the present embodiment, the drop-off restricting portion 5f2 is separated from the contact portion 5c1, so that the width of the bent portion 5f1 of the hook portion 5f can be made larger than that of the contact portion 5c1, and the strength of the hook portion 5f is increased. It becomes possible to increase compared with the hook part 5c of the said 1st Embodiment. Other configurations and operational effects are the same as those in the first embodiment.

  The configuration of the present invention is not limited to those exemplified in the above embodiments, and the material, shape, dimensions, form, number, arrangement location, and the like are appropriately changed without departing from the gist of the present invention. Is possible.

  For example, in each of the above embodiments, the first barrier blade 3 is made of resin, but may be formed of metal for further thinning the barrier mechanism and the lens barrel 110.

  Moreover, in each said embodiment, the notch part 4b of the 2nd barrier blade 4 is optical axis direction in the whole rotation range of the drop-off control part 5c2, 5f2 from the closed position of the barrier blades 3-5 to the open position. Although the case where the movement to the image plane side is restricted is illustrated, the present invention is not limited to this.

  Therefore, in the present invention, the range in which the drop-off restricting portion 5c2 overlaps with the notch portion 4b of the second barrier blade 4 in the optical axis direction is a range in which the barrier blades 3 to 5 extend from the closed position to the open position. On the closed side, the area where the barrier blade 4 overlaps the barrier blade 5 is small.

  In this region, when the second barrier blade 4 is pushed in by an external force from the subject side, the cutout portion 4b moves in the optical axis direction. For this reason, the state which does not overlap with the contact part 5c1 occurs in the optical axis direction, and a phenomenon occurs in which the notch part is separated from the U-shaped hook part during the opening and closing of the barrier blade which has occurred in the conventional barrier mechanism.

  Accordingly, the drop-off restricting portions 5c2 and 5f2 rotate within the rotation range from the closed position to the open position of the barrier blades 3 to 5 so that the tip of the barrier blade 4 moves in the optical axis direction by an external force at least from the subject side. The movement of the notch 4b of the barrier blade 4 to the image plane side in the optical axis direction may be restricted within the range.

  For example, the drop-out restricting portions 5c2 and 5f2 are notched portions 4b of the second barrier blade 4 at least in a range of 50% from the closed position in the rotation range from the closed position to the open position of the barrier blades 3 to 5. The movement to the image plane side in the optical axis direction may be restricted.

3 1st barrier blade 4 2nd barrier blade 4b Notch 4d drop-off restricting part 5 3rd barrier blade 5c hook part 5c1 contact part 5c2 drop-off restricting part 5f hook part 5f1 bending part 5f2 drop-off restricting part 110 lens mirror Tube

Claims (5)

A photographing optical system in which a subject light beam enters through an opening, and an opening position for opening the opening and a closing position for closing the opening are provided so as to be rotatable around a rotation shaft on the base end side. A lens barrel having a pair of barrier blades,
The plurality of barrier blades include a subject-side barrier blade disposed on the subject side, and an image-plane-side barrier blade disposed on the subject-side barrier blade on the image plane side in the optical axis direction of the subject-side barrier blade. With
At the tip side of the subject side barrier blade, the tip of the image side barrier blade is at least in the optical axis direction by an external force from at least the subject side in the rotation range of the plurality of barrier blades from the closed position to the open position. A drop-out restricting portion that engages the image plane side barrier blade in the optical axis direction and regulates the movement of the image plane side barrier blade in the optical axis direction in the rotation range that moves to the image plane side. A lens barrel.   The drop-off restricting portion is in an optical axis direction with respect to the image plane side barrier blade in at least a range of 50% from the closed position in a rotation range of the plurality of barrier blades from the closed position to the open position. The lens barrel according to claim 1, wherein the lens barrel is engaged with the lens barrel.   3. The lens according to claim 1, wherein the drop-off restricting portion is provided continuously to a bent portion that is bent toward the image plane at an outer peripheral portion in an opening / closing direction on a front end side of the subject-side barrier blade. A lens barrel.   The drop-off restricting portion is disposed outside a turning radius of a tip end portion of a barrier blade excluding the subject-side barrier blade and the image plane-side barrier blade among the plurality of barrier blades. The lens barrel according to any one of 1 to 3. An optical device including a lens barrel,
An optical apparatus comprising the lens barrel according to any one of claims 1 to 4 as the lens barrel.

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