JP4403461B2 - Lens hood mounting structure - Google Patents

Description

  The present invention relates to a lens hood mounting structure, and in particular, a flower-shaped lens hood in which long and short surfaces are alternately provided at intervals of approximately 90 degrees along the circumferential direction is mounted to a lens barrel via a bayonet mechanism. It relates to the lens hood mounting structure.

  In general, an image frame of a still camera or a video camera has a rectangular shape. In contrast, the optical system is circular. Therefore, when the amount of incident light from the top and bottom is equal to the amount of incident light from the left and right, the amount of light per unit area is relatively increased in the upper and lower portions. A difference occurs in the light amount distribution above. In order to eliminate such a difference, a so-called flower lens hood is used.

  The flower-shaped lens hood has a circular base end and a petal shape at the distal end. The long and short surfaces are alternately formed at intervals of 90 degrees. It is positioned up and down, and the short surface is positioned to the left and right, and by adjusting the protrusion amount of the long and short surfaces, the distribution of light quantity in the vertical and horizontal directions on the image frame is adjusted to an appropriate value become able to.

  Japanese Patent Application Laid-Open No. 2001-264851 discloses a lens hood in which a lens hood having a base end portion having a cylindrical shape and a tip end portion having a petal shape is detachably attached to a photographing lens barrel via a bayonet mechanism. The bayonet mechanism includes three lens barrel side engaging portions disposed in the circumferential direction at the distal end portion of the lens barrel, and circumferentially at the proximal end portion of the lens hood so as to be engageable therewith. The lens optical axis direction engagement in one pair of the pair of the lens barrel side engaging portion and the hood side engaging portion which are composed of three arranged lens side engaging portions and are closely engaged with each other. The dimension is set to a value different from the engagement dimension in the optical axis direction in the other pairs, the size of the engagement claw is small, and the appearance of the camera is not deteriorated. A lens hood device that can be used There.

Such a lens hood apparatus has a drawback that the mounting structure thereof is very complicated, in particular, the claws must be made in triplicate, the mold structure is complicated, and the manufacturing cost increases. On the other hand, if the flower-shaped lens hood is not correctly attached, not only will the light amount be adjusted correctly, but it will also be difficult to operate the lens ring such as zoom and focus if the posture during storage is incorrect. is there.
JP 2001-264851 A JP 2002-40517 A

  The subject of this invention is providing the attachment structure of the lens hood which can adjust the light quantity distribution of an up-down direction and the left-right direction correctly, when it mounts | wears correctly.

  Another object of the present invention is to provide a lens hood mounting structure that facilitates the operation of the lens ring when it is mounted in the retracted position, thereby preventing the operability of the camera from being impaired.

  Still another object of the present invention is to provide a lens hood mounting structure in which the structure for mounting the lens hood is simple, thereby reducing the cost.

  Still another object of the present invention is to provide a lens hood mounting structure in which the mounting structure of the lens barrel portion with respect to the lens hood is simple so that the cost of the barrel portion does not increase.

  Still another object of the present invention is to provide a lens hood attachment structure in which the lens hood is correctly attached to the lens barrel during mounting and use of the lens hood so that there is no risk of erroneous mounting. That is.

  Still another object of the present invention is to provide a lens hood mounting structure in which a mechanism for the mounting structure is not easily damaged even when a rotation operation is performed by applying an excessive force.

  The above-described problems and other problems of the present invention will be made clear by the technical idea of the present invention described below and the embodiments thereof.

The main invention of the present application is a lens hood in which a flower-shaped lens hood in which long and short surfaces are alternately provided at intervals of approximately 90 degrees along the circumferential direction is attached to a lens barrel via a bayonet mechanism. In the mounting structure,
On the outer peripheral surface of the lens barrel, an engaged portion that extends in the circumferential direction is provided, and a contacted portion that protrudes in the optical axis direction is formed at the center in the length direction of the engaged portion,
On the inner peripheral surface of the lens hood, the optical axis is displaced in the circumferential direction by a distance approximately equal to the width of the engaged portion with respect to the optical axis direction and by a distance substantially equal to the length of the engaged portion. Forming a pair of engaging portions, forming contact portions projecting in the optical axis direction so as to face each other on opposite ends of the engaging portions;
The lens hood is fitted in the forward or reverse direction with respect to the lens barrel, the engaged portion of the lens barrel is brought into contact with one engaging portion of the lens hood, and the lens hood is The lens hood mounting structure is characterized in that the engaged portion is narrowly attached by the pair of engaging portions by being rotated by an angle corresponding to substantially half of the length of the engaging portion.

  Here, the lens hood may be coupled to the lens barrel in a state where the long surface is positioned up and down and the short surface is positioned right and left. The lens hood may be housed by being coupled to the lens barrel in the reverse direction with the long surface positioned vertically and the short surface positioned horizontally. Further, the engaged portion of the lens barrel may be constituted by a ridge that is arranged so that the abutted portion coincides with the upper and lower central portions of the lens barrel. Further, the engaging portion of the lens hood may be a pair of protrusions formed vertically so as to be shifted to both sides in the circumferential direction with respect to a substantially central portion of the lens hood.

  In addition, a locking portion is provided on the lens barrel side, and a locking portion is provided on the lens hood side. When the lens hood is correctly attached in the forward direction or the reverse direction, the locking portion is engaged. The stop may be locked. Further, the locked portion may be a protrusion, and the locking portion may be a concave portion. Moreover, the said latching | locking part may be a groove part formed in the protrusion which comprises the engaging part formed in the internal peripheral surface of the said lens hood.

  A preferred aspect of the present invention relates to a camera lens hood mounting structure that is detachably attached to a lens barrel via a bayonet mechanism, and in particular, the shape of the lens hood connected to the connecting portion of the lens barrel is This relates to a flower-shaped hood where the upper and lower parts are different from the left and right parts. Here, a claw is provided in the circumferential direction of each of the lens barrel and the lens hood, and the claw is joined by a combination of the claw.

  At least one claw on the lens barrel side is provided with respect to a plane parallel to the optical axis direction, while the claw on the lens hood side is symmetrical with respect to the plane perpendicular to the optical axis direction. The surfaces parallel to the axial direction are provided separately from each other in steps, and the nail on the lens barrel side is inserted and fixed by a pair of claws. In addition, the lens hood part and the lens barrel part are each provided with a click part to notify the user of the completion of mounting and to prevent the lens hood from being detached from the lens barrel without the user's intention. .

  According to such an aspect, when the lens hood is stored, the long surface of the lens hood is positioned on the upper surface of the lens barrel, and the operability of the ring portion of the lens barrel is not hindered. Further, the structure of the lens hood and the lens barrel is simplified, thereby reducing the molding cost. In addition, there is less risk of incorrect mounting when using the lens hood.

  The main invention of the present application is a lens hood in which a flower-shaped lens hood in which long and short surfaces are alternately provided at intervals of approximately 90 degrees along the circumferential direction is attached to a lens barrel via a bayonet mechanism. In the mounting structure, an engaged portion that extends in the circumferential direction is provided on the outer peripheral surface of the lens barrel, and a contacted portion that protrudes in the optical axis direction is provided at the center in the length direction of the engaged portion. Formed on the inner peripheral surface of the lens hood with a distance substantially equal to the width of the engaged portion with respect to the optical axis direction, and shifted in the circumferential direction by a distance substantially equal to the length of the engaged portion. A pair of engaging portions are formed, and abutting portions projecting in the optical axis direction so as to face each other are formed at opposite ends of the engaging portions, and the lens hood is in the positive direction with respect to the lens barrel Or, it can be fitted in the opposite direction and the engaged part of the lens barrel can be Engaging portion and is brought into contact, the lens hood to be equivalent to the angle rotated approximately half the length of the engaging portion, in which so as to narrow wearing engaged portion by the pair of engaging portions.

  Therefore, according to such a lens hood mounting structure, the lens hood is fitted in the forward or backward direction with respect to the lens barrel, and one of the lens hoods is engaged with the engaged portion of the lens barrel. The lens barrel is engaged by the pair of engaging portions on the lens hood side by rotating the lens hood at an angle corresponding to half of the length of the engaging portion. As a result, the lens hood is securely held while being mounted on the lens barrel. Therefore, it becomes possible to attach the lens hood with a simple structure and with a correct posture.

  The present invention will be described below with reference to an embodiment shown in the drawings. FIG. 1 shows the entire structure of an electronic still camera using a lens hood according to the present embodiment. A grip that bulges forward is provided on the side of a rectangular parallelepiped camera body 10 having an image sensor as a light receiving portion. The part 11 is continuously provided. A finder 12 is provided on the upper part of the camera body 10 so that the finder 12 can be used to look into the subject image.

  A cylindrical lens barrel 15 is continuously provided in front of the camera body 10 and substantially at the center thereof. A lens hood 16 is detachably attached to the distal end side of the lens barrel 15. The lens hood 16 is composed of a synthetic resin molded body, and the base end portion of the lens hood 16 has a cylindrical shape. On the other hand, the front end side of the lens hood 16 has a flower shape, and a pair of long surfaces 17 are provided on the top and bottom, and a pair of short surfaces 18 are formed on the left and right. These long surfaces 18 narrow the amount of light from the top and bottom and suppress the amount of light from the left and right, thereby making the light amount distribution in the vertical and horizontal directions uniform for a horizontally long rectangular image frame. I try to figure it out.

  As shown in FIG. 1, the lens hood 16 has a lens so as to sandwich the engaged portion 21 formed on the outer peripheral surface of the lens barrel 15 as shown in FIG. The engaging portions 25 and 26 on the hood 16 side are closely attached. At this time, the engaging portion 26 is positioned on the front side of the engaged portion 21, and the engaging portion 25 is positioned on the rear side of the engaged portion 21.

  As shown in FIG. 3, the lens hood 16 is housed on the outer peripheral surface of the lens barrel 15 in the direction opposite to that in use. At this time, as shown in FIG. 4, the engaged portion 21 on the side of the lens barrel 15 is narrowly attached by the engaging portions 25 and 26, and the engaging portion 25 is positioned in front of the engaged portion 21, The engaging portion 26 is located on the rear side.

  When the lens hood 16 is mounted on the outer peripheral surface of the lens barrel 15, the long surface 17 of the lens hood 16 is positioned up and down, so that zoom and focus lens rings can be operated on the outer peripheral surface of the lens barrel 15. Making it easy.

  Next, an attachment structure for attaching the lens hood 16 to the lens barrel 15 will be described. As shown in FIGS. 5 and 6, the lens barrel 15 has a circumferential surface on the outer peripheral surface thereof. A protrusion 21 extending in the direction is formed, and this protrusion 21 constitutes an engaged portion. A protrusion 22 protruding in the optical axis direction is formed so as to be positioned at an intermediate position in the length direction of the protrusion 21 and substantially at the center of the upper and lower portions of the lens barrel 15. The protrusion 22 constitutes a contacted portion. Further, protrusions 23 are formed on both sides of the protrusion 22 to constitute a locked portion. Such a configuration is formed on the outer peripheral surface of the lens barrel 15 and on the upper and lower portions thereof.

  On the other hand, on the lens hood 16 side, as shown in FIGS. 7 to 9, protrusions 25 and 26 are projected on the inner peripheral surface on the base end side in the circumferential direction with respect to the lens barrel 15. They are formed with a distance that is substantially equal to the length of the strip 21. Moreover, these protrusions 25 and 26 are displaced from each other in the optical axis direction. That is, it is separated in the optical axis direction by a length corresponding to the dimension for receiving the protrusion 21 on the lens barrel 15 side (width of the protrusion 21). And these protrusion 25,26 comprises the engaging part. Further, a bent portion 27 is formed by bending in the optical axis direction at opposite ends of the protrusions 25 and 26 in the circumferential direction, thereby constituting a contact portion. Further, groove portions 28 are formed on the protrusions 25 and 26, and these groove portions 28 respectively constitute locking portions.

  Thus, in the present embodiment, the lens hood 16 is attached to the opposite side of the camera body 10 with respect to the lens barrel 15 attached to the front end of the camera body 10. The lens hood 16 has a circular connection surface with the lens barrel 15, and the shape of the front end side for light shielding is a flower shape, and the long surface 17 of the lens hood 16 is on the upper surface with respect to the camera body 10. The short surface 18 is attached so as to be in the lateral direction. In use, as shown in FIG. 2, the protrusions 25 and 26 attached to the lens hood 16 are fixed by pinching the protrusions 21 on the lens barrel 15 side.

  On the other hand, when the lens hood 16 is housed, as shown in FIG. 3, the lens hood 16 is reversed and attached on the outer peripheral surface of the lens barrel 15 so that the long surface 17 is on the upper side. In addition, at the time of storage, as shown in FIG. 4, the protrusion 21 of the lens barrel 15 is narrowly fixed by the pair of protrusions 25 and 26 of the lens hood 16.

  A protrusion 21 is provided along the periphery of the lens barrel 15 to fix the lens hood 16, and a protrusion 22 for mounting and fixing the lens hood 16 at the correct position is an optical axis at the center. Protruding in the direction.

  On the other hand, on the lens hood 16 side, as shown in FIG. 9 in particular, protrusions 25 and 26 for fixing the lens hood 16 to the connection portion, a bent portion 27 for preventing erroneous mounting, and mounting A groove 28 is formed for providing a click feeling indicating completion.

  In particular, in the development view of the lens hood 16 shown in FIG. 9, the arrow 35 indicates the direction of the distal end side of the long surface 17 of the lens hood. Is provided. One ridge 25 is close to the base end surface of the lens hood 16, and includes a bent portion 27 for preventing erroneous mounting and a groove portion 28 for providing a click feeling indicating the completion of mounting at the left end thereof. The other ridge 26 is formed on the arrow 35 side with an interval approximately equal to the width in the optical axis direction of the ridge 21 of the lens barrel 15 from the ridge 25, and at the right end thereof. A bent portion 27 that is bent to the opposite side of the arrow 35, that is, the proximal end side, is formed, and a groove portion 28 is formed in the ridge 26.

  Such an engagement structure of the lens hood 16 is engaged with an engagement structure on the outer peripheral surface of the lens barrel 15. As shown in FIG. 6, the lens barrel 15 has a protrusion 21 for fixing the lens hood 16, a protrusion 22 for fixing the lens hood 16 at the correct position, and a click feeling of completion of mounting. A pair of projections 23 are provided. A dotted line 36 indicates the center of the upper part of the lens barrel. Therefore, the protrusion 21 is provided symmetrically with respect to the center of the upper part of the camera.

  Next, an operation for mounting such a lens hood 16 on the lens barrel 15 will be described. When the lens hood 16 is attached in use, the petals of the lens hood 16 are in the direction opposite to the lens barrel 15, and the side end of the protrusion 26 of the lens hood 16 with respect to the lens barrel 15. Is fitted so as to be in contact with the side end of the protrusion 21 of the lens barrel 15 (see FIG. 10A). Thereafter, the lens hood 16 is rotated in the direction of the arrow 37. As a result, the relationship between the relative positions of the lens hood 16 and the lens barrel 15 is as shown in FIG. 10B. Here, the pair of protrusions 25, 26 of the lens hood 16 are positioned on both sides of the protrusion 21 of the lens barrel 15, and the end of the protrusion 25 on the lens hood 16 side with respect to the protrusion 22 is Touch.

  In this state, the groove 28 of the lens hood 16 and the protrusion 23 of the lens barrel 15 change from the state shown in FIG. 12A to the state shown in FIG. 12B, and the protrusion 23 falls into the groove 28 to generate a click feeling. Therefore, the user can know from the click feeling that the user is in the wearing state. At this time, the long surface 17 on the upper surface of the lens hood 16 is positioned on the upper portion of the lens barrel 15 and is properly attached (see FIG. 1).

  When the lens hood 16 is rotated in the reverse direction in FIG. 10A, that is, in the direction of the arrow 38 during the mounting operation as described above, the ridge 26 of the lens hood 16 is placed on the right end of the ridge 21 of the lens barrel 15. The right end bent portion 27 comes into contact, and the lens hood 16 cannot be rotated. Therefore, even if the lens hood 16 is erroneously rotated in the reverse direction, it is not erroneously attached.

  In order to store the lens hood 16 in the opposite direction, when the lens hood 16 is attached to the outer periphery of the lens barrel 15, the ridge 25 of the lens hood 16 is connected to the rim 25 of the lens barrel 15, as shown in FIG. 11A. The lens hood 16 is fitted into the lens barrel 15 from the optical axis direction so as to come into contact with the lens 21. When the lens hood 16 is rotated in the direction indicated by the arrow 39 in this state, the state shown in FIG. 11B is obtained, and the protrusion 21 of the lens barrel 15 is tightly attached by the protrusions 25 and 26 on both sides of the lens hood 16. It becomes a state. In addition, at this time, the protrusion 23 of the protrusion 21 of the lens barrel 15 falls into the groove 28 of the protrusions 25 and 26 of the lens hood 16 to produce a click feeling (see FIG. 12B), and the completion of the attachment can be confirmed. When the mounting is completed, the long surface 17 of the lens hood 16 coincides with the upper portion of the lens barrel 15, so that the long surface 17 of the lens hood 16 can be used for zooming and focusing operations of the lens barrel 15. It won't get in the way.

  Although the present invention has been described above with reference to the illustrated embodiments, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the technical idea of the invention included in the present application. For example, the design of the position of the protrusion 21 on the lens barrel 15 and the length, position, number, etc. of the protrusions 25 and 26 on the inner peripheral surface of the lens hood 16 in the above embodiment can be arbitrarily changed. .

  The present invention can be widely used for a lens hood mounting structure in various imaging apparatuses such as an electronic still camera, a silver salt film still camera, and a video camera.

It is an external appearance perspective view of an electronic still camera. It is the side view which fractured | ruptured a part which shows the attachment structure of the lens hood. FIG. 3 is a perspective view of the camera in a state in which the lens hood is reversed and stored on the lens barrel. It is the side view which fractured | ruptured a part which shows the holding mechanism of the lens hood. It is a principal part perspective view of the front-end | tip part of a lens-barrel. It is an expanded top view which shows the attachment structure of the lens hood on a lens-barrel. It is an external appearance perspective view of a lens hood. It is a perspective view when a lens hood is seen from the reverse direction. It is a perspective view which shows the attachment structure on the internal peripheral surface of a lens hood. It is a development top view showing operation of attachment of a lens hood to a lens barrel. It is an expanded top view which shows the accommodation operation | movement of the lens hood on a lens barrel. It is a principal part expanded vertical sectional view which shows the latching structure by a protrusion and a groove part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Camera body, 11 ... Grip part, 12 ... Finder, 15 ... Lens barrel, 16 ... Lens hood, 17 ... Long face, 18 ... Short face, 21 ... Projection (engaged part), 22 ... Projection ( Contacted part), 23 ... projection (locked part), 25, 26 ... ridge (engagement part), 27 ... bent part (contact part), 28 ... groove part (locking part), 35 ... Arrow, 36 ... dotted line, 37-39 ... arrow

Claims (8)

In the lens hood mounting structure in which the flower-shaped lens hood, in which the long surface and the short surface are alternately provided at intervals of approximately 90 degrees along the circumferential direction, is mounted on the lens barrel via a bayonet mechanism.
On the outer peripheral surface of the lens barrel, an engaged portion that extends in the circumferential direction is provided, and a contacted portion that protrudes in the optical axis direction is formed at the center in the length direction of the engaged portion,
On the inner peripheral surface of the lens hood, the optical axis is displaced in the circumferential direction by a distance approximately equal to the width of the engaged portion with respect to the optical axis direction and by a distance substantially equal to the length of the engaged portion. Forming a pair of engaging portions, forming contact portions projecting in the optical axis direction so as to face each other on opposite ends of the engaging portions;
The lens hood is fitted in the forward or reverse direction with respect to the lens barrel, the engaged portion of the lens barrel is brought into contact with one engaging portion of the lens hood, and the lens hood is An attachment structure for a lens hood, wherein the engaged portion is closely attached by the pair of engaging portions by rotating an angle corresponding to substantially half of the length of the engaging portion.   The lens hood mounting structure according to claim 1, wherein the lens hood is coupled to the lens barrel with a long surface positioned vertically and a short surface positioned horizontally.   2. The lens hood according to claim 1, wherein the lens hood is accommodated by being coupled to the lens barrel in a reverse direction with a long surface positioned vertically and a short surface positioned horizontally. Lens hood mounting structure.   2. The engaged portion of the lens barrel is constituted by a ridge that is arranged so that the abutted portion coincides with the upper and lower central portions of the lens barrel. Lens hood mounting structure.   The engaging portion of the lens hood is a pair of ridges formed vertically so as to be shifted to both sides in the circumferential direction with respect to a substantially central portion of the lens hood. 4. A lens hood mounting structure according to 4.   A locking portion is provided on the lens barrel side, and a locking portion is provided on the lens hood side. When the lens hood is correctly attached in the forward direction or the reverse direction, the locking portion is locked. The lens hood mounting structure according to claim 1, wherein the portion is locked.   The lens hood mounting structure according to claim 6, wherein the locked portion is a protrusion and the locking portion is a recess. The lens hood mounting structure according to claim 6, wherein the locking portion is a groove portion formed in a protrusion that constitutes an engaging portion formed on an inner peripheral surface of the lens hood.

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