JP5463703B2 - Barrier mechanism, lens barrel, and imaging device - Google Patents

Description

  The present invention relates to a barrier mechanism, a lens barrel, and an imaging device that are used in an optical apparatus such as a camera, and more particularly to a barrier mechanism, a lens barrel, and an imaging device that are excellent in space saving and maintainability and that can operate smoothly. Is.

  Opening and closing operation on the objective surface side of the optical system in an imaging apparatus such as a camera having a moving lens barrel driven by a motor to shield the objective surface side in the closed state, and the objective surface of the optical system is contaminated by dust and fingers Various types of barrier mechanisms have been proposed as barrier mechanisms for protecting them from the like.

  As an example of the barrier mechanism, there is a barrier mechanism that includes a plurality of barrier blades that can rotate on a plane perpendicular to the optical axis, and that opens and closes the objective surface side of the optical system by rotating the barrier blades. . In this type of barrier mechanism, a barrier blade driving member is used to rotate the barrier blade. The barrier blade driving member is a member that rotates in response to the forward and backward movement of the lens barrel, and the barrier blade is rotated by transmitting the rotation operation of the barrier blade driving member to the barrier blade.

  Since both the barrier blades and the barrier blade driving member are members that rotate, it is necessary to provide a configuration (hereinafter referred to as a “rotation center portion”) that serves as a rotation center for each. These rotation center portions are respectively provided on a plane perpendicular to the optical axis in the lens barrel and ahead of the lens in the optical axis direction.

  Conventionally, like the barrier mechanism described in Patent Document 1, a barrier mechanism in which barrier blades and the center of rotation of a barrier driving member are arranged so as to overlap in the optical axis direction has been used.

  In this barrier mechanism, the barrier blade is urged in a direction to be always closed by a barrier closing spring. In addition, the barrier drive member includes a main portion that includes a shaft portion having a cam surface inclined in the optical axis direction and a spring receiving portion formed at the front portion of the shaft portion in the optical axis direction. The spring receiving portion accommodates a barrier opening spring that always urges the barrier driving member so as to rotate in the direction in which the barrier blades are opened.

  When the lens barrel is extended, since the operation of the barrier driving member is not restricted, the barrier driving member abuts on the barrier blade and urges the barrier blade in the opening direction. The barrier closing spring urges the barrier blade in the closing direction. However, since the urging force of the barrier opening spring is larger than the urging force of the barrier closing spring, the barrier blade is in an opened state.

  On the other hand, when the lens barrel is retracted, the pressing portion of the float key attached to the fixed cylinder so as to be able to advance and retreat in the optical axis direction comes into contact with the cam surface of the barrier drive member so that the barrier drive member does not contact the barrier blade. It is rotated. Therefore, only the urging force of the barrier closing blade is applied to the barrier blade, and the barrier blade is closed.

  Thus, in the barrier mechanism described in Patent Document 1, the above-described configuration is aimed at downsizing the lens barrel as compared with the conventional configuration.

  Also, in order to improve the maintainability while reducing the size of the lens barrel, it is configured as a unit like the barrier mechanism described in Patent Document 2, and the barrier mechanism unit is replaced when the barrier mechanism fails. Therefore, a barrier mechanism that can easily perform maintenance such as repair of a failure is also used.

  However, in the invention described in the cited document 1, the barrier driving member is required to have strength because it directly receives the pressing force from the float key, and it is necessary to provide a shaft portion having a cam surface and a spring receiving portion. End up. Moreover, it is necessary to ensure the space for installing this wider than the space for installing the rotation center part of a barrier blade | wing. For this reason, when the rotation center portions of the barrier drive member and the barrier blade are provided so as to overlap in the optical axis direction, it is necessary to select a position where they are provided in accordance with the rotation center of the barrier drive member requiring a larger space. Therefore, since only a barrier blade does not require a large space, a rotation center can be provided in the vicinity of the inner peripheral surface of the lens barrel. However, in the invention described in the cited document 1, this cannot be done. The center of rotation of the barrier blade and the barrier driving member is provided at a position where the distance from the distance is wide, that is, at a portion close to the optical axis.

  When the center of rotation of the barrier blade is provided near the optical axis, the rotation angle of the barrier blade required to close the opening increases, and the amount of momentum required for driving the barrier increases, increasing the resistance of camera operation. Smooth operation will be hindered.

  Further, in the invention described in the cited document 2, when the barrier mechanism is configured as a unit, the barrier unit is fixed to the lens barrel by screws or the like separately from the attachment of each component in the barrier mechanism. (Hereinafter referred to as “fixed portion”). In order to firmly fix the barrier unit having a large structure, it is necessary to ensure the mechanical strength, and it is necessary that the fixing portion has a certain large structure. It is necessary to secure a large space for providing such a fixing portion to some extent. Moreover, it is necessary to ensure a fixed part in the position which does not prevent operation | movement of a barrier blade | wing and a barrier blade drive member.

  While it is necessary to secure a wide space for storing the barrier blades opened at the time of imaging, in order to secure a wide space for providing the fixing portion, it is necessary to increase the diameter of the lens barrel. It was an obstacle to downsizing the trunk.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a barrier mechanism, a lens barrel, and an imaging apparatus that are excellent in space saving and maintainability and can operate smoothly.

The present invention is disposed on the front side of the lens barrel of the image pickup apparatus, when not in operation of the imaging device shields the effective optical path of the optical system, at the time of operation of the imaging device in the barrier mechanism for opening the effective optical path, the aperture A barrier cover having a portion, a barrier blade driving member that rotates in response to the driving force of the retracting of the lens barrel, and a plurality of members that rotate in conjunction with the rotation of the barrier blade driving member and shield the effective optical path A barrier substrate having a substrate opening corresponding to an effective optical path, the barrier blade driving member, and a barrier substrate having a substrate opening corresponding to an effective optical path, in a plane perpendicular to the optical axis of the optical system. in the projected position relationship for rotation center of the barrier blade driving member is between the outer periphery of the barrier substrate and the substrate opening, and, viewed from the optical axis, is driven by the barrier driving member So as to overlap with the operating range of the barrier blades, together with the barrier blade driving member is provided on the barrier substrate, the barrier blades, the rotational center than the center of rotation of the barrier blade driving member the most important feature that is provided in the barrier substrate so as to be located outwardly relative to the optical axis.

Although not particularly limited in the present invention, it is disposed on the front side of the lens barrel of the imaging device, shields the effective optical path of the optical system when the imaging device is inoperative, and opens the effective optical path when the imaging device is in operation. A barrier mechanism, a holding cylinder that holds the barrier mechanism and holds the lens movably, and a lens barrel side drive member that transmits a driving force of the operation of retracting the lens barrel to the barrier mechanism
It is preferable that the barrier mechanism is the above-described barrier mechanism.

  Although not particularly limited in the present invention, it is preferable that the lens barrel side driving member abuts on a barrier blade driving member of the barrier mechanism to transmit the driving force.

  Further, although not particularly limited in the present invention, it is preferable that the holding cylinder has a light shielding member that covers a contact portion between the lens barrel side driving member and the barrier blade driving member.

  Although not particularly limited in the present invention, the barrier cover, the barrier blade driving member, the barrier blade, and the barrier substrate are preferably configured as a unit integrally assembled.

  Further, although not particularly limited in the present invention, the barrier blade is preferably composed of at least four blades.

  Although not particularly limited in the present invention, when the barrier blades shield the effective light path, at least two of the at least four blades of the barrier blade come into contact with the barrier blade driving member and It is preferable that the barrier blade driving member is rotated in conjunction with the rotation of the barrier blade driving member, and the other blades are rotated following the operation of the blade.

  Although not particularly limited in the present invention, when the barrier blade opens the effective optical path, at least two of the at least four blades of the barrier blade are rotated by the biasing force of the spring member. At the same time, it is preferable that the other blades rotate following the operation of the blades.

  The present invention is also an imaging apparatus including a lens barrel, wherein the lens barrel is the lens barrel described above.

The present invention also provides a barrier blade that rotates about a first rotation axis between a closed position that shields at least part of the optical path of the imaging optical system and an open position that retracts from the optical path, and a second rotation A barrier mechanism comprising: a barrier blade driving member that rotates about an axis to drive the barrier blade; and a barrier substrate that rotatably holds the barrier blade driving member and includes an opening including the optical path. , the width of the first direction of the opening, the greater than substantially vertical second width before Symbol in a first direction of the opening, said first axis of rotation, said first direction in the disposed remote outside by opening said second rotary shaft in the second direction, it is arranged remote outside by the opening, viewed in the optical axis direction of the imaging optical system When arranged in a range overlapping the barrier blades in the open position, Between the rear blade driving member and the barrier blades, the barrier substrate is arranged, the first direction is a longitudinal direction of the imaging elements constituting the imaging optical system, the second direction is the imaging the short-side direction der Rukoto elements and main features.

  Further, although not particularly limited in the present invention, it is preferable that the barrier blade is rotatably held by the barrier substrate.

  Although not particularly limited in the present invention, the barrier blade driving member includes a protrusion that extends in the optical axis direction of the imaging optical system, and the barrier substrate extends along the optical axis direction of the imaging optical system. It is preferable that a first through-hole portion is provided, and the protruding portion is in contact with the barrier blade and moves while being inserted into the through-hole portion.

  Further, although not particularly limited in the present invention, it is preferable that a biasing member that biases the barrier blade toward the closed position is provided, and the protruding portion regulates the position of the barrier blade.

  Although not particularly limited in the present invention, a barrier fixing member that holds the barrier substrate and moves with the barrier substrate in the optical axis direction of the imaging optical system, and the imaging optical system with respect to the barrier fixing member A rectilinear drive member that is relatively movable in the optical axis direction, the barrier fixing member includes a second through-hole portion along the optical axis direction of the imaging optical system, and the rectilinear drive member, It is preferable that the barrier blade driving member is inserted into the second through-hole portion, contacts the barrier blade driving member, and drives the barrier blade driving member.

  Although not particularly limited in the present invention, the first through-hole portion and the second through-hole portion are at different positions when viewed from the optical axis direction of the imaging optical system, and overlap. Preferably not.

  Although not particularly limited in the present invention, the barrier blade driving member includes a slope inclined with respect to the optical axis direction of the imaging optical system, and the rectilinear drive member remains in contact with the slope, It is preferable to move relative to the barrier fixing member in the optical axis direction of the imaging optical system and rotate the barrier blade driving member.

  Further, although not particularly limited in the present invention, a shutter unit that can move relative to the barrier fixing member in the optical axis direction of the imaging optical system is provided, and the shutter unit holds the rectilinear drive member. It is preferable that the shutter unit and the rectilinear drive member move together in the optical axis direction of the imaging optical system.

  In the present invention, although not particularly limited, it is preferable that a light shielding member is provided between the second through-hole portion and the optical path of the imaging optical system.

  According to the present invention, it is possible to provide a barrier mechanism, a lens barrel, and an imaging device that are excellent in space saving and maintainability and can operate smoothly.

It is a disassembled perspective view which shows the whole structure of the barrier mechanism which concerns on embodiment of this invention. In the barrier mechanism according to the embodiment of the present invention, it is a main part plan view showing a state in which the light shielding rib of the barrel attaching barrel covers the periphery of the barrier driving member. In the barrier mechanism according to the embodiment of the present invention, it is a main part perspective view showing a state in which the light shielding rib of the barrel attaching barrel covers the periphery of the barrier driving member. It is a front view which shows a mode that a space arises in a barrier board | substrate in embodiment of this invention in the state in which the inner blade | wing and the outer blade | wing were opened. It is a front view which removes an outer blade | wing and shows the state of FIG. It is a rear view which shows a mode that a space arises in a barrier board | substrate in embodiment of this invention. It is a principal part perspective view which shows a mode that an outer blade | wing follows the operation | movement of an inner blade | wing when the barrier blade | wing which concerns on embodiment of this invention opens. It is a rear view of the state of FIG. It is a principal part perspective view which shows a mode that an outer blade | wing follows the operation | movement of an inner blade | wing when a barrier blade | wing closes. FIG. 10 is a rear view of the state of FIG. 9. It is sectional drawing which shows the state which the lens barrel which concerns on embodiment of this invention extended. It is a principal part perspective view which shows the positional relationship of the barrier unit and the lens barrel side drive member in the state of FIG. FIG. 12 is an enlarged side view of the barrier driving member and the lens barrel side driving member in the state of FIG. 11. It is sectional drawing which shows the state which the lens barrel which concerns on embodiment of this invention retracted. It is an enlarged view of A area | region of FIG. It is a principal part perspective view which shows the positional relationship of the barrier unit and the lens barrel side drive member in the state of FIG. FIG. 15 is an enlarged side view of the barrier driving member and the lens barrel side driving member in the state of FIG. 14. It is a modification of the barrier mechanism which concerns on this invention, Comprising: It is a principal part top view which shows the relationship between the inner blade | wing and barrier drive member when an inner blade opens. It is a modification of the barrier mechanism which concerns on this invention, Comprising: It is a principal part top view which shows the relationship between the inner blade | wing and barrier drive member when an inner blade closes.

<Barrier mechanism>
An embodiment of a barrier mechanism according to the present invention will be described with reference to the drawings. In the following description, a barrier mechanism used in a retractable digital camera will be described as an example. However, the present invention is not limited to this, and a single-lens reflex camera and a lens shutter camera using a silver salt film, as well as digital and analog The present invention can also be applied to various optical devices such as video cameras.

  As shown in FIG. 1, in the barrier mechanism 1 according to the present embodiment, a barrier unit 3 is attached to a barrier mechanism-attached barrel (hereinafter also referred to as “second rectilinear cylinder”) 2 from the front in the optical axis O direction. It has been.

  The barrier mechanism-attached barrel 2 corresponds to the innermost rectilinear barrel among the plurality of barrels of the retractable digital camera, and is a member that holds the barrier mechanism and also holds a plurality of lenses. A rib 22 having an opening 24 is provided in the vicinity of the subject side of the lens closest to the subject side of the lens barrel 2 to which the barrier mechanism is attached, and the barrier unit 3 is screwed around the outer peripheral edge of the rib 22 on the subject side. A screw hole 21 is provided for fixing. Further, as shown in FIG. 2, the rib 22 has a pin through-opening through which a driving pin 101 of a lens barrel side driving member 10, which will be described later, penetrates the barrier mechanism mounting barrel 2 and contacts the barrier driving member 7 when retracted. A portion 25 is provided.

  Further, as shown in FIGS. 2 and 3, the barrier mechanism mounting lens barrel 2 is substantially U-shaped so as to cover the entire barrier driving member 7 and the pin penetration opening when the barrier mechanism is assembled. A light-shielding rib 23, which is a long plate-like member, is continuously provided on the subject side of the rib 22 on the inner peripheral surface of the barrier mechanism-attached barrel 2.

  By providing such a light shielding rib 23, it is possible to prevent light entering from the opening window 65 of the barrier substrate 6 from entering the imaging surface side through the pin penetration opening 25.

  Further, the through hole 66 provided in the barrier substrate 6 and the pin through opening 25 provided in the barrier mechanism mounting barrel 2 are provided so as not to overlap each other when viewed from the optical axis direction. Therefore, the light passing through the through hole 66 can be prevented from passing through the pin through opening 25, and stray light can be prevented from entering the image sensor.

  Further, with such a configuration, the movement of the driving pin 101 of the lens barrel side driving member 10 in the optical axis direction is converted into driving of the barrier blade 5 via the barrier driving member 7. Easy to adjust the amount of force applied to the.

  As will be described later, when the barrier blade 5 is closed, the drive pin 101 contacts the tapered surface 74 of the cam portion 73 of the barrier drive member 7 through the pin through opening 25 and the blade drive of the barrier drive member 7. The arm 72 contacts the inner blade 53 of the barrier blade 5 through the through hole 66. Because of such a configuration, the amount of force applied to the barrier blade 5 can be adjusted by adjusting the shape of the tapered surface 74, the distance from the rotation axis R2 of the cam portion 73 and the blade driving arm 72, and the like.

  As shown in FIGS. 2, 5, and 6, the rotation center portion R <b> 2 of the barrier driving member 7 penetrates the through hole 66 provided in the barrier substrate 6 so that the blade driving arm 72 of the barrier driving member 7 penetrates. And the pin penetration opening 25 provided in the rib 22 of the barrier mechanism mounting barrel 2 in order for the drive pin 101 of the lens barrel side drive member 10 to pass therethrough. Therefore, the center of rotation of the barrier driving member 7 becomes an obstacle, and stray light can be prevented from passing through the pin through opening 25 from the through hole 66 and entering the imaging surface side.

  The feeding operation of the other lens barrel and the barrier mechanism mounting barrel 2 and the relationship between this feeding operation and the operation of the barrier unit 3 will be described later.

  The barrier unit 3 is a member for opening and closing the effective optical path of the digital camera. The barrier unit 3 is provided with a barrier cover 4 from the subject side, a barrier blade 5 composed of four wings, and two opening direction urging members 55, and two barriers from the back side. The drive member 7, the two opening direction biasing members 8, and the two drive member mounting pins 9 are attached.

  The barrier substrate 6 is a substantially disk-like substrate to which each member constituting the barrier unit 3 is attached, and an opening window 65 that forms an effective optical path together with an opening window 43 of a barrier cover described later is formed. The opening window 65 has a rectangular shape with a short side in the vertical direction and a long side in the horizontal direction.

  On the front side of the barrier substrate 6, two locking pins 61 are integrally formed at symmetrical positions. When the wire spring is wound around the locking pin 61, the hole portion 551 of the closing direction urging member 55 having a hole portion 551 in the middle portion in the length direction, and the hole portion 531 of the inner blade 53 described later. The hole 511 of the outer blade 51 and the locking hole 47 of the barrier cover 4 are fitted. As a result, the inner blade 53 and the outer blade 51 are locked in a space formed by the barrier substrate 6 and the barrier cover 4 so as to be rotatable about the rotation axis R1 defined by the locking pin 61. The barrier cover 4 is positioned with respect to the barrier substrate 6 in the rotational direction. Further, on the front side of the barrier substrate 6, two locking pins 62 for positioning the barrier cover 4 in the rotational direction with respect to the barrier substrate 6 by fitting into the locking holes 48 of the barrier cover 4 are provided. It is formed in a symmetrical position. Further, on the front side of the barrier substrate 6, a closing direction urging member locking portion (not shown) is formed to lock the closing direction urging member 55 so as to be able to urge the inner blade 53 in the closing direction. Yes.

  On the peripheral surface of the barrier substrate 6, four locking projections 63 for positioning and attaching the barrier cover 4 in the optical axis direction are formed by locking the locking claws 41 of the barrier cover 4. .

  On the back side of the barrier substrate 6, the driving member mounting pin 9 is passed through the hole portion 81 of the opening direction biasing member 8 having the hole portion 81 and the shaft hole 71 formed in the barrier driving member 7. The two drive member attachment parts which are not shown in figure and become the rotation center of the barrier drive member 7 for fitting to and attaching the barrier drive member 7 so that rotation is possible are provided.

  As shown in FIG. 4, when the barrier driving member 7 is attached to the back side of the barrier substrate 6, the blade driving arm 72 of the barrier driving member 7 passes through the through hole 66 of the barrier substrate 6 and the subject side of the barrier substrate 6. To protrude.

  The closing direction biasing member 55 is a spring material made of a torsion spring or the like, and is attached to the barrier substrate 63 by inserting and engaging the hole 551 with the fitting convex portion 61 of the barrier substrate 63. In the state in which the barrier unit 3 is assembled, one end of the closing direction biasing member 55 abuts on a spring abutting portion (not shown) of the inner blade 53 of the barrier blade 3 and the other end is a barrier. It abuts against the substrate 63 and constantly urges the inner blade 53 in the closing direction.

  The barrier blade 5 includes four blades of two outer blades 51 having the same shape and two inner blades 53 having the same shape. One outer blade 51 and one inner blade 53 form a pair, and the other one outer blade 51 and the other inner blade 53 form another pair to constitute the barrier blade 5.

  The outer blade 51 is a long plate-like member, and an axial hole 511 is formed at one end, and the other end is in a direction that is rearward in the optical axis direction when assembled to the barrier unit 3. A protruding end contact piece 515 is formed. Further, a central contact piece that protrudes rearward in the optical axis direction is provided between the hole 511 and the end contact piece 515 and on an upper side surface that is parallel to the optical axis direction when assembled to the barrier unit 3. 513 is formed.

  The inner blade 53 is a long plate-like member, and a shaft hole 531 is formed at one end portion, and an end protruding piece 535 protruding in the longitudinal direction is formed at the other end portion. A notch 537 is provided in the vicinity of the rear portion 531.

  The barrier cover 4 is a member provided on the subject side of the barrier blade 5 and is formed in a disk shape having an opening window 43 in the center. The opening window 43 has a rectangular shape, and forms an effective optical path together with the opening window 65 of the barrier substrate 63 described above. Further, the barrier cover 4 is provided with four locking claws 41 for locking to the locking projections 63 of the barrier substrate 6 and at positions facing the screw holes 21 of the barrier mechanism mounting barrel 2 when assembled. The pair of insertion holes 45, the pair of boss holes 47 into which the fitting convex portions 61 are inserted and disposed at positions facing the fitting convex portions 61 of the barrier substrate 6 when assembled, and the barrier substrate 6 when assembled. A pair of second boss holes 48 are formed, which are arranged at positions facing the second fitting convex portions 62 and into which the second fitting convex portions 62 are fitted.

  The barrier drive member 7 is a member for converting the forward / backward movement of the lens barrel into the drive of the barrier blade 5, and an engaging portion (not shown) provided on the back surface of the barrier substrate 6 together with the opening direction biasing member 8. The drive member mounting pin 9 is used to rotate about the rotation axis R2. The barrier drive member 7 includes a shaft hole 71 into which the drive member mounting pin 9 is inserted, a barrier drive pin 72 that contacts the notch 537 of the inner blade 53 when the lens barrel is extended, and a lens barrel described later when the lens barrel is retracted. It has a cam portion 73 that contacts the drive pin 101 of the side drive member 10. A tapered surface 74 is provided at a portion of the cam portion 73 that contacts the drive pin 101. The barrier drive pin 72 and the cam portion 73 are provided at both ends of the barrier drive member 7 with the shaft hole 71 as a boundary.

  The opening direction urging member 8 is a spring material made of a torsion spring or the like, one end of which abuts against the cam portion 73 of the barrier driving member 7, and the other end provided on the barrier substrate 6 (not shown). It is attached by the drive member attachment pin 9 in a state of being in contact with the contact portion. The opening direction urging member 8 constantly urges the barrier driving member 7 to rotate in the direction in which the inner blades 53 are opened. In this embodiment, two barrier driving members 7 and two opening direction biasing members 8 are also provided.

  In the barrier unit 3 of the barrier mechanism 1 according to the above-described embodiment, the aspect ratio of the imaging area of the imaging element is 4: 3, so that the opening window 43 provided in the barrier cover 4 and the barrier substrate 6 are provided. The shapes of the provided opening windows 65 are the same, and are rectangular with the ratio of the length of the long side to the short side being 4: 3.

  In the barrier cover 4 and the barrier substrate 6 having the opening window having such a shape, the space formed between each side of the opening window and the circumferential portion of the barrier cover 4 or the barrier substrate 6 is not uniform. . That is, the space (hereinafter referred to as “long side space”) in the short direction (long side) rather than the space (hereinafter referred to as “short side space”) in the longitudinal direction (short side) of the opening window. ”) Is wider.

  4 to 6, the rotation axis R1 of the barrier blade 5 is provided in the vicinity of the circumference of the short side space on the front surface side of the barrier substrate 6, that is, at the position farthest from the optical axis O. In the open state of the barrier blade 5, the barrier blade 5 is accommodated in a wide long side space. Further, a rotation axis R2 of the barrier driving member 7 is also provided on the back side of the long side space, as will be described later.

  Thus, by providing the rotation axis R1 of the barrier blade 5 at the position farthest from the optical axis on the front side of the barrier substrate 6, the rotation angle of the barrier blade 5 during the opening / closing operation of the barrier blade 5 is minimized. be able to. That is, by reducing the momentum necessary for driving the barrier, the resistance of the lens barrel can be reduced and the smooth operation can be realized. In addition, since the storage of the barrier blade 5 requiring the largest space is performed in the long side space on the front side of the barrier substrate 6, the short side space includes the rotation center of the barrier blade 5 and the back side described later. Only the space where the barrier drive pin 72 of the protruding barrier drive member 7 protrudes may be disposed. Therefore, the space saving property is improved in the short side space, and the space S that is not provided for driving the barrier blades without any members can be secured.

  Here, if the distance from the optical axis O to the rotation axis R1 of the barrier blade 5 is L2, L2 is a minimum space necessary for providing the rotation axis R1 of the barrier blade 5 from the radius of the barrier substrate 6. It is the distance minus the distance for the radius.

  On the other hand, as shown in FIG. 6, the rotation axis R2 of the barrier driving member 7 that requires a larger space than the rotation axis R1 of the barrier blade 5 is also provided in a wide long side space on the back surface side of the barrier substrate 6. Therefore, most of the barrier driving member 7 is located in the long side space. The transmission of power from the barrier driving member 7 to the barrier blade 5 is performed by causing the barrier driving pin 72 of the barrier driving member 7 to protrude from the back surface side through the through hole 66 to the front surface side in the short side space. This is done by bringing it into contact.

  As described above, on the back surface side of the barrier substrate 6, the most part of the barrier driving member 7 other than the barrier driving pins 72 is located in the long side space, and only the barrier driving pins 72 are in the short side space. Therefore, even in the short side space, a space S ′ where no member is arranged can be secured.

  As described above, in the present embodiment, the barrier blades 5 and the barrier driving member 7 in the open position overlap each other when viewed from the optical axis direction in the long side space on the front side and the back side of the barrier substrate 6. Is arranged. In order to arrange the barrier blades 5 and the barrier driving member 7, a wide space is required. However, in order to perform this in a wide long side space, the members are provided in the short side space on the front side and the back side of the barrier substrate 6. The space S and S ′ can be secured. Since these spaces S and S ′ are provided so as to overlap when viewed from the optical axis O direction, notches can be provided in portions corresponding to these spaces of the barrier substrate 6. Thereby, the space for providing the insertion hole 45 in the barrier unit 3 for fixing the barrier unit 3 to the barrier mechanism attachment lens barrel 2 using a screw is secured.

  Here, if the distance from the optical axis O to the rotation axis R2 of the barrier driving member 7 is L1, L1 is the minimum necessary for providing the rotation axis R2 of the barrier driving member 7 from the radius of the barrier substrate 6. It is the distance obtained by subtracting the distance corresponding to the radius of the space. Since the space required for providing the rotation axis R2 is wider than the space required for providing the rotation axis R1, L1 and L2 satisfy the relationship L2> L1. That is, on the barrier substrate 6, the rotation axis R <b> 1 of the barrier blade 5 is provided on the radially outer side than the rotation axis R <b> 2 of the barrier driving member 7. As described above, in this embodiment, the rotation center R1 of the barrier blade 5 is provided more radially outside the barrier substrate 6 than the conventional barrier mechanism in which the two rotation centers R1 and R2 are provided in an overlapping manner. it can. Thereby, the rotation angle of the barrier blade 5 during the opening / closing operation of the barrier blade 5 can be minimized. That is, by reducing the momentum necessary for driving the barrier, the resistance of the lens barrel can be reduced and the smooth operation can be realized.

  As in the above-described embodiment, by making the barrier cover 4, the barrier blade 5, the barrier substrate 6, and the barrier driving member 7 into one barrier unit 3, when any of these components fails, These parts do not need to be disassembled and replaced, and can be easily and quickly repaired simply by replacing the barrier unit 3.

  Further, in a barrier mechanism using a conventional barrier unit, it is difficult to provide a fixing portion without increasing the diameter of the barrier unit. However, in the barrier unit 3 of the above-described embodiment, spaces S and S ′ in which no parts are arranged in the short side space can be secured, so that the barrier unit 3 is fixed to this portion without increasing the diameter of the barrier unit. An insertion hole 45 as a part can be provided. Therefore, the barrier unit of the present embodiment has a configuration excellent in space saving.

  In the present embodiment, the optical axis O and the center of the opening 65 of the barrier substrate 6 have the same position when viewed from the optical axis direction. However, the present invention is not limited to this. The optical axis O and the center of the opening 65 of the barrier substrate 6 may not be at the same position. Even in that case, with the opening 65 of the barrier substrate 6 as the center, the distance from the center to the rotation axis R1 of the barrier blade 5 is longer than the distance from the center to the rotation axis R2 of the barrier driving member 7. Thus, the same effect as that of the above embodiment can be obtained.

  Next, how the outer blades 51 and the inner blades 53 of the barrier blade 3 in the present embodiment work together will be described with reference to FIGS.

  In a state where the barrier driving member 7 is attached to the barrier substrate 6, the blade driving arm 72 of the barrier driving member 7 always projects to the subject side of the barrier substrate 6 through the through hole 66 of the barrier substrate 6, and the inner blade 53 is cut. The state is in contact with the notch 537.

  When the lens barrel is extended, the inner blade 53 of the barrier blade 3 receives a pressing force from the barrier driving member 7 (not shown in FIGS. 7 to 10). The opening direction biasing member 8 always biases the barrier driving member 7 so as to rotate in the direction in which the inner blade 53 is opened. Since this urging force is stronger than the urging force of the closing direction urging member 55 in the direction of closing the inner blade 53, the inner wing 53 is opened by the barrier driving member 7 when the lens barrel is extended. . The relationship between the movement of the lens barrel and the operation of the barrier driving member will be described later.

  When the inner blade 53 rotates in the opening direction, the upper contact surface 533 of the inner blade 53 contacts the central contact piece 513 of the outer blade 51 as shown in FIGS. 7 and 8. The central abutment piece 513 receives the rotational force in the opening direction of the inner blade 53, so that the outer blade 51 is driven to open by the inner blade 53.

  On the other hand, when the lens barrel is retracted, the barrier driving member 7 does not contact the inner blade 53 as will be described later. Then, only the urging force in the direction in which the inner blade 53 is closed by the closing direction urging member 55 acts on the inner blade 53, so that the inner blade 53 rotates in the closing direction.

  When the inner blade 53 rotates in the closing direction, as shown in FIGS. 9 and 10, the end protrusion piece 535 of the inner blade 53 protrudes in the direction of the inner blade 53 of the outer blade 51. 515 abuts. Then, the end abutment piece 515 receives the rotational force in the closing direction of the inner blade 53, so that the outer blade 51 is driven and closed by the inner blade 53.

  Thus, since the outer blade 51 is rotated following the rotation of the inner blade 53, the effective optical path can be opened and closed with a simple configuration.

  In this embodiment, the effective light path is opened and closed by using a total of four blades, two inner blades and two outer blades. However, the present invention is not limited to this, and an even number of blades is used. For example, two or six or more blades may be used. Even in such a barrier mechanism, the same effect as the barrier mechanism according to the above-described embodiment can be obtained.

<Lens barrel>
An embodiment of a lens barrel according to the present invention will be described. As shown in FIG. 11, the lens barrel includes a fixed cylinder 16 fixed to a camera body 18 having an image sensor 20, a rotary cylinder 14 that is rotatably fitted inside the fixed cylinder 16, and a rotary cylinder 20. And a second rectilinear cylinder (moving forward and backward in the optical axis direction between the retracted position and the imaging position by the rotation of the rotating cylinder 20). Barrier mechanism mounting barrel) 2 and four lens barrels.

  A helicoid screw (not shown) is formed between the inner peripheral surface of the fixed cylinder 16 and the outer peripheral surface of the rotary cylinder 14 and between the rotary cylinder 14 and the second rectilinear cylinder 2. The second rectilinear cylinder 2 is restricted in movement in the rotation direction by a mechanism (not shown) and can be moved back and forth in the optical axis direction.

  Therefore, when the rotating cylinder 14 is driven to rotate by a motor (not shown) and moves forward and backward in the optical axis direction from the fixed cylinder 16, the second rectilinear cylinder 2 that receives the rotational force of the rotating cylinder 14 rotates. Therefore, only the forward / backward movement in the optical axis direction is performed.

  The rectilinear cylinder 12 is attached to the rotating cylinder 14 so that the operation of the rotating cylinder 14 in the optical axis direction is restricted, and the rotating cylinder 14 is rotatable with respect to the rectilinear cylinder 12. Further, the rectilinear cylinder 12 is attached to the fixed cylinder 16 so as to be movable back and forth in the optical axis direction while being restricted from rotating with respect to the fixed cylinder 16.

  Therefore, when the rotating cylinder 14 rotates and advances and retracts in the optical axis direction, the rectilinear cylinder 12 allows the rotating cylinder 14 to rotate and is driven by the operation of the rotating cylinder 14 in the optical axis direction to move in the optical axis direction. Perform forward / backward movement.

  Further, the above-described barrier unit 3 and the lens barrel side drive member 9 are provided inside the lens barrel.

  The barrier unit 3 is attached to the tip of the second rectilinear cylinder 2 on the subject side using screws. Therefore, the barrier unit 3 advances and retreats according to the advance / retreat operation of the rectilinear cylinder 2 in the optical axis direction.

  Further, the lens barrel side drive member 9 is locked to a helicoid screw (not shown) of the rotating cylinder 14 and also locked to a straight groove (not shown) of the fixed cylinder 16, thereby restricting the rotation inside the lens barrel. However, it is attached so that it can advance and retreat in the optical axis direction. Therefore, the lens barrel side drive member 9 receives the rotation of the rotary cylinder 14 and advances and retreats in the lens barrel in the optical axis direction.

  As shown in FIGS. 11 to 13, when the lens barrel is extended, the barrier drive member 7 of the barrier unit 3 and the drive pin 101 of the barrel side drive member 10 are not in contact with each other. It has become.

  As described above, in this state, the opening direction biasing member 8 biases the barrier driving member 7 so as to rotate in the direction in which the inner blade 53 is opened. Since this urging force is stronger than the force that the closing direction urging member 55 urges the inner blade 53 in the closing direction, the inner blade 53 is opened, and the outer blade 51 is also opened following the inner blade 53. The effective light path is released.

  On the other hand, as shown in FIGS. 14 to 16, when the lens barrel is retracted, the barrier driving member 7 of the barrier unit 3 and the driving pin 101 of the lens barrel side driving member 10 are in contact with each other. It is in a state. When the driving pin 101 contacts and presses the tapered surface 74 of the cam portion 73 when the lens barrel is retracted, the barrier driving member 7 rotates and the contact between the barrier driving member 7 and the inner blade 53 is released.

  As described above, when the barrier driving member 7 is not in contact with the inner blade 53, the inner blade 53 only acts on the inner blade 53 in the direction of closing the inner blade 53 by the closing direction biasing member 55. 53 is rotated in the closing direction, and the outer blade 51 is also closed by following the inner blade 53, and the effective optical path is closed.

  According to the lens barrel of the above-described embodiment, since the barrier mechanism can be reduced in size, the lens barrel can be reduced in size. Further, since a barrier unit is used for the barrier mechanism, in the event of a failure, only the barrier unit needs to be replaced without disassembling the entire barrier mechanism, so that maintenance can be facilitated and quickened. Furthermore, according to the lens barrel of the above-described embodiment, the amount of movement of the barrier blades required to open and close the barrier blades can be reduced, so that the lens barrel can be smoothly advanced and retracted.

  In the present embodiment, the inner blade is biased in the closing direction and the barrier driving member is biased in the opening direction. However, the present invention is not limited to this, and various modes can be adopted. .

  For example, as a modification of the present invention, the inner blade may be urged in the opening direction by the opening direction urging member, and the urging mechanism may not be provided in the barrier driving member.

  In this case, when the lens barrel is extended, as shown in FIG. 17, the inner blade is opened by the biasing force of the unillustrated opening direction biasing member, and the barrier driving member is also rotated by the rotation of the inner blade. It has become a state. In FIG. 17 and FIG. 18, the outer blade is not shown, but the inner blade operates in accordance with the inner blade.

  On the other hand, when the lens barrel is retracted, the barrier driving member comes into contact with a lens barrel side driving member (not shown) and is rotated in a direction to close the inner blade. Since this rotational force is stronger than the pressing force in the opening direction by the opening direction biasing member, as shown in FIG. 18, the inner blade is rotated in the closing direction, and the effective optical path is closed. Since other configurations are the same as those in the above embodiment, the description thereof is omitted here.

  The same effect as that of the barrier lens barrel according to the above-described embodiment can be obtained by the barrier lens barrel according to such a modification.

<Imaging device>
An embodiment of an imaging apparatus according to the present invention will be described using a digital camera as an example. The digital camera according to the present embodiment includes a shutter button, a power button, a lens barrel having a plurality of lenses, a finder, a strobe, a battery, an image recording memory card insertion unit, and the like that are pressed during shooting. The lens barrel is the lens barrel according to the present invention described above.

  As described above, since the lens barrel according to the present invention can be easily downsized as compared with the conventional lens barrel, the entire digital camera according to the present embodiment can be reduced in size and weight.

  Further, by using the lens barrel according to the present invention, the momentum of the barrier blades necessary for opening and closing the barrier blades can be reduced. Therefore, in this digital camera, the lens barrel can be smoothly moved back and forth, and power consumption can be suppressed.

  In the present embodiment, a digital camera has been described as an example of an imaging apparatus. However, the present invention is not limited to this, and a single lens reflex camera and a lens shutter camera using a silver salt film, a digital and analog video camera, and the like. The present invention can also be applied to various optical devices.

1 Barrier mechanism 2 Barrier mechanism mounting barrel (straight-ahead barrel)
DESCRIPTION OF SYMBOLS 21 Screw hole 23 Shading rib 3 Barrier unit 4 Barrier cover 5 Barrier blade 51 Outer blade 53 Inner blade 55 Opening direction biasing member 6 Barrier substrate 65 Opening window 7 Barrier driving member 8 Opening direction biasing member 9 Drive member mounting pin 10 Mirror Body side drive member

Japanese Patent No. 4190402 JP 2006-259615 A

Claims (18)

Disposed on the front side of the lens barrel of the image pickup apparatus, when not in operation of the imaging device shields the effective optical path of the optical system, at the time of operation of the imaging device in the barrier mechanism for opening the effective optical path,
A barrier cover having an opening;
A barrier blade driving member that rotates in response to the driving force of the retractable lens barrel;
A plurality of barrier blades that rotate in conjunction with the rotation of the barrier blade driving member and shield the effective optical path;
The barrier blade driving member and the barrier blade are rotatably attached, and a barrier substrate having a substrate opening corresponding to an effective optical path;
With
In the positional relationship projected on a plane perpendicular to the optical axis of the optical system,
The center of rotation of the barrier blade driving member is between the substrate opening and the outer periphery of the barrier substrate, and when viewed from the optical axis direction, the operating range of the barrier blade driven by the barrier driving member The barrier blade driving member is provided on the barrier substrate so as to overlap,
The barrier blade is a barrier mechanism provided on the barrier substrate such that the center of rotation of the barrier blade is located outside the rotation center of the barrier blade driving member with respect to the optical axis . A barrier mechanism that is disposed on the front side of the lens barrel of the imaging apparatus, shields the effective optical path of the optical system when the imaging apparatus is inoperative, and opens the effective optical path when the imaging apparatus is in operation;
A holding cylinder for holding the barrier mechanism and holding the lens movably;
A lens barrel side drive member that transmits the driving force of the operation of retracting the lens barrel to the barrier mechanism;
A lens barrel with
The lens barrel according to claim 1, wherein the barrier mechanism is a barrier mechanism.   The lens barrel according to claim 2, wherein the lens barrel side driving member contacts the barrier blade driving member of the barrier mechanism and transmits the driving force.   The lens barrel according to claim 2, wherein the holding cylinder includes a light shielding member that covers a contact portion between the lens barrel side driving member and the barrier blade driving member.   The barrier mechanism according to claim 1, wherein the barrier cover, the barrier blade driving member, the barrier blade, and the barrier substrate are integrated as a unit.   The barrier mechanism according to claim 1 or 5, wherein the barrier blade is composed of at least four blades.   When the barrier blades shield the effective light path, at least two of the at least four blades of the barrier blade are in contact with the barrier blade driving member and interlock with the rotation of the barrier blade driving member. The barrier mechanism according to claim 6, wherein the barrier mechanism rotates and the other blades rotate following the operation of the blades.   When the barrier blade opens the effective optical path, at least two of the barrier blades rotate by the biasing force of the spring member, and the other blades act on the blade. The barrier mechanism according to claim 6 or 7, which is rotated by being driven.   An imaging apparatus comprising a lens barrel, wherein the lens barrel is a lens barrel according to any one of claims 2 to 4. A barrier blade that rotates about a first rotation axis between a closed position that blocks at least a part of the optical path of the imaging optical system and an open position that retracts from the optical path;
A barrier blade driving member that rotates around a second rotation axis to drive the barrier blade;
A barrier substrate holding the barrier blade driving member rotatably and having an opening including the optical path;
In the barrier mechanism with
Width in the first direction of the opening is longer than the substantially perpendicular second width prior Symbol first direction of said opening,
Said first rotation axis, in said first direction, disposed remote outside by the opening,
Said second rotary shaft in the second direction, is arranged remote outside by the opening, when viewed in the optical axis direction of the imaging optical system, it overlaps the barrier blades in the open position Placed in range,
The barrier substrate is disposed between the barrier blade driving member and the barrier blade ,
Wherein the first direction is a longitudinal direction of the imaging elements constituting the imaging optical system, the second direction is the short side direction der Ru barrier mechanism of the imaging device. The barrier mechanism according to claim 1, 9 or 10 , wherein the barrier blade is rotatably held on the barrier substrate. The barrier blade driving member includes a protrusion extending in the optical axis direction of the imaging optical system;
The barrier substrate includes a first through-hole portion along an optical axis direction of the imaging optical system;
The barrier mechanism according to claim 10 or 11 , wherein the protruding portion contacts the barrier blade and moves while being inserted into the through-hole portion. The barrier mechanism according to claim 12 , further comprising an urging member that urges the barrier blade toward the closed position, wherein the protruding portion regulates a position of the barrier blade. A barrier fixing member that holds the barrier substrate and moves with the barrier substrate in an optical axis direction of the imaging optical system;
A rectilinear drive member movable relative to the barrier fixing member in the optical axis direction of the imaging optical system,
The barrier fixing member includes a second through-hole portion along the optical axis direction of the imaging optical system,
Said linear drive member, said is inserted into the second through hole portion, the barrier blade driving member abuts, according to any one of claims 10 to 13, characterized in that for driving the barrier blade driving member Barrier mechanism. Said first through-hole, and the second through hole portion, when viewed from the optical axis of the imaging optical system, located in different positions, and, according to claim 14, wherein the non-overlapping Barrier mechanism. The barrier blade driving member includes a slope inclined with respect to the optical axis direction of the imaging optical system;
The linear drive member moves relative to the barrier fixing member in the optical axis direction of the imaging optical system while abutting the inclined surface, and rotates the barrier blade drive member. Item 14. A barrier mechanism according to Item 14 or 15 . A shutter unit movable relative to the barrier fixing member in the optical axis direction of the imaging optical system;
The shutter unit holds the linear drive member;
The shutter unit and said linear drive member, wherein the imaging optical system of a barrier mechanism according to any one of claims 14 to 16, characterized in that both moves in the optical axis direction. Wherein between the second optical path and the through hole portion of the imaging optical system, a barrier mechanism according to any one of claims 14 to 17, characterized in that the light blocking member is provided.

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