JP6544884B2 - Lens barrier device, lens barrel and camera - Google Patents

Description

  The present invention relates to a lens barrier device for opening and closing a lens opening provided in a lens cover provided on the front surface of a lens barrel, and a lens barrel and a camera provided with the lens barrier device.

  In an optical apparatus represented by a digital compact camera, a lens barrier device is provided in which a lens aperture provided in front of a lens barrel is opened in use but closed to protect the lens when not in use. There is. Conventionally, a pair of barrier blades is disposed at a position facing the lens opening as the lens barrier device, and the lens opening is closed or opened by rotating the barrier blades in the radial direction of the lens barrel by the drive mechanism. Structures have been proposed. For example, in Patent Document 1, first, second, and third barrier blades forming a pair are provided in the front surface area of the lens barrel, and the first and second to third barrier blades are interlocked. A lens barrier device has been proposed in which the dimension in the lens optical axis direction is reduced by driving the lens.

JP 2012-150173 A

  Since the technique of Patent Document 1 has a configuration in which a plurality of pairs of barrier blades are overlapped in the lens optical axis direction, the dimension in the lens optical axis direction is increased. Further, a barrier drive member for driving these barrier blades is required, and it is difficult to reduce the dimension in the lens optical axis direction also by arranging the barrier drive member. In Patent Document 1, the barrier driving member is disposed along the periphery of the lens in order to suppress the dimension in the lens optical axis direction of the lens barrier device, but with this, the outer diameter dimension of the lens barrel becomes large. Furthermore, since the lens barrier device is configured in the lens holding frame that holds the lens in Patent Document 1, the weight of the lens holding frame also increases. Therefore, when the lens, that is, the lens barrel configured to move the lens holding frame in the direction of the lens optical axis is designed, the load for driving the lens holding frame becomes large, and the lens holding frame can be quickly and power-saving. There is also a problem that it is difficult to drive.

  For such a lens barrier device, as employed in an embodiment of the present invention described later, an independent barrier holding cylinder is disposed along the outer periphery of the lens holding frame, and a lens is provided on the front surface of the barrier holding cylinder. The structure which provides a barrier apparatus integrally can be considered. In this way, the lens holding frame need not be provided with the lens barrier device, so the dimensions of the lens holding frame in the lens optical axis direction and the lens radial direction are reduced, and the lens holding frame is driven quickly and with power saving. It will be advantageous above. However, in such a configuration, since the lens holding frame is driven inside the barrier holding cylinder, the internal size of the barrier holding cylinder, that is, the lens optical axis direction in which the lens holding frame can be moved In order to secure the dimension of (1), it is required to further reduce the dimension of the lens barrier device in the lens optical axis direction. Further, since the overall diameter dimension of the lens barrel is increased by the barrier holding cylinder, it is required to suppress the diameter dimension of the barrier holding cylinder, in particular, the dimension in the radial direction of the lens barrier device disposed in the barrier holding cylinder. It will be done.

An object of the present invention is to provide a lens barrier device in which the dimension of the barrier holding cylinder for protecting the lens in the lens optical axis direction is made as small as possible while securing the lens movement amount in the lens optical axis direction. It is. Another object of the present invention is to provide a lens barrel and a camera provided with such a lens barrier device.

The present invention is a lens barrier device provided in a barrier holding cylinder disposed on the outer periphery of a lens cylinder, and for driving a barrier blade for opening and closing a lens opening provided in the barrier holding cylinder and for opening and closing the barrier blade. The drive levers of the lens are disposed on the same plane perpendicular to the lens optical axis . Furthermore, a first spring that rotationally biases the drive lever with respect to the barrier holding cylinder, and a second spring that pivotally biases the barrier blade to the drive lever are provided . As a preferred embodiment of this lens barrier device, a barrier substrate supported by a barrier holding cylinder and provided in close proximity in the lens optical axis direction and a barrier cover are provided, and the barrier blade and the drive lever are between the barrier cover and the barrier substrate. The lens is disposed in a minute gap in the direction of the lens optical axis. Also, the barrier blades are arranged symmetrically with respect to the lens optical axis, and are constituted by a pair of plate members that open and close the lens opening by the change of the rotational position on the surface, and the drive lever is for each of the barrier blades. It is provided, and it is comprised by a pair of board member which changes the rotational position of each barrier blade | wing by the rotational position change of self.

  Further, in the present invention, a cam cylinder which is disposed along the inner peripheral surface of the barrier holding cylinder and rotates the drive lever when rotated around the lens optical axis is provided. Furthermore, a first spring for imparting rotational behavior to the drive lever and a second spring for imparting rotational behavior to the barrier blade are provided, and the first and second springs are provided on the barrier substrate. It is furnished in the provided notch. Here, the first spring pivotally biases the drive lever against the barrier substrate, the second spring pivotally biases the barrier blade against the drive lever, and the cam cylinder acts as the first drive lever. The drive lever is configured to be forcibly rotated in the direction opposite to the rotational bias of the spring, and the drive lever is in a position to open the lens opening against the bias of the second spring by the bias of the first spring. When it is rotated and forcedly rotated by the cam cylinder against the biasing force of the first spring, the barrier blade is pivoted in the direction to close the lens opening by the biasing force of the second spring.

  Furthermore, as a preferable embodiment of the present invention, the barrier substrate includes a control piece for preventing displacement and deformation of the drive lever in the plate thickness direction, and the drive lever is sandwiched between the control piece and the barrier substrate. I assume. Further, the drive lever is provided with a contact piece that contacts the barrier blade, and one of the contact portions between the contact piece and the barrier blade is provided with a contact rib whose dimension in the plate thickness direction is increased. In addition, the drive lever is provided with a contact piece to be in contact with the barrier blade, and at least one of the contact surfaces of the contact piece and the barrier blade is subjected to surface treatment such as painting or plating to enhance lubricity. It may be done.

  The barrier blade in the present invention is preferably made of resin, and the drive lever is preferably made of metal. Further, the barrier holding cylinder is configured to be fed out from the storage position of the camera body, and the cam cylinder is drawn out of the barrier holding cylinder, is rotated about the lens optical axis along with the storage operation, and is rotated by the barrier blade. It is preferable to open the lens opening and close the lens opening with the barrier blade by rotation upon storage.

A lens barrel of the present invention is characterized by including the above-described lens barrier device of the present invention. A camera according to the present invention is characterized by including the above-described lens barrel.
Configure

According to the present invention, since the barrier blade for opening and closing the lens opening and the drive lever for opening and closing the barrier blade are arranged on the same plane perpendicular to the lens optical axis, the lens optical axis direction Can be made thinner.

Sectional drawing at the time of accommodation of the lens unit of embodiment of this invention. Sectional drawing at the time of extension of the lens unit. The partial disassembled perspective view of the lens unit. The front view and rear view which removed the barrier cover in the state which the lens barrier apparatus opened the lens opening. The front view and rear view which removed the barrier cover in the state which the lens barrier apparatus obstruct | occluded the lens opening. The expansion perspective view of the vicinity part of a drive lever when opening lens opening. FIG. 8 is an enlarged perspective view of the vicinity of the drive lever when the lens opening is closed. The perspective view which looked at the vicinity part of the drive lever from diagonally opposite direction. The front view and BB sectional drawing of the vicinity part of a drive lever. The disassembled perspective view of the barrier holding | maintenance cylinder containing a cam cylinder, and a fixed cylinder. The internal structure figure of the cam cylinder for demonstrating the cam operation | movement of a cam cylinder.

  Next, embodiments of the present invention will be described with reference to the drawings. 1 and 2 are sectional views of a lens barrel of a camera to which the present invention is applied as a lens unit LU, taken along the lens optical axis Lx. FIG. 1 shows the lens unit LU as a camera body CB. FIG. 2 shows a state in which the lens unit LU is drawn out from the camera body CB, in a state of being stored. FIG. 3 is a partial exploded perspective view of the lens unit LU. In the lens unit LU, the rotary barrel 2 is held on the inner periphery of a fixed barrel 1 fixed to a camera body CB shown by a chain line in FIGS. 1 and 2, and the straight barrel 3 and the lens barrel 4 are arranged inside the rotary barrel 2 They are provided and helicoid coupled to the rotary cylinder 2 respectively. The rotating cylinder 2 is rotated around the lens optical axis Lx by the driving force of a delivery motor or the like not appearing in these figures, and the rectilinear cylinder 3 and the lens cylinder 4 are accommodated in FIG. From the state, as shown in FIG. 2, the camera body CB is straightly moved and fed forward (to the subject side, hereinafter, the subject side is referred to as the front and the opposite side as the rear in the front-rear direction). The straight advance barrel 3 and the lens barrel 4 are coupled to the rotary barrel 2 by another helicoid, so the amount of extension is different. That is, the extension amount L3 of the straight barrel 3 is larger than the extension amount L4 of the lens barrel 4. Therefore, as shown in FIG. 2, a dimension L1 obtained by subtracting a dimension L2 in the lens optical axis direction of the lens barrier device described later from the difference (L3−L4) of the extension amount The lens holding frame 42 is a space for moving in the lens optical axis direction.

  The lens barrel 4 is composed of a motor frame 41 disposed on the rear side in the lens optical axis direction, and a lens holding frame 42 disposed on the front side of the motor frame 41. The motor frame 41 is internally supported by the rotary cylinder 2, and as described above, when the straight cylinder 3 is drawn by the rotation of the rotary cylinder 2, the motor frame 41 is drawn to a predetermined position together with the straight cylinder 3. A lead screw 412 and a stepping motor 411 for driving the lead screw are mounted on the motor frame 41. Further, a follower 421 screwed to the lead screw 412 is mounted on the lens holding frame 42. A lens driving device is configured by the lead screw 412, the stepping motor 411, and the follower 421, and the lens holding frame 42 is movable in the lens optical axis direction with respect to the motor frame 41 by the lens driving device. There is. The lens holding frame 42 has a structure in which a lens frame 42A holding the front lens group Lf and a focus frame 42B holding the shutter S and the rear lens group Lr are integrated, and the lens driving device is moved in the lens optical axis direction. Focusing in the lens unit LU is performed by movement control.

  On the other hand, the straight-moving cylinder 3 is configured as a barrier holding cylinder in the present invention, and the barrier device 5 is integrally attached to the front end of the straight-moving cylinder 3. The barrier device 5 includes a barrier substrate 51, a barrier cover 52 disposed on the front side of the barrier substrate 51, and a cam cylinder 53 which is installed inside the straight-moving cylinder 3 and is rotated about the lens optical axis Lx. It consists of The barrier substrate 51 is fixedly supported by the front end portion of the straight advance barrel 3, and the barrier cover 52 is further fixed to the front surface of the barrier substrate 51. At the center of the barrier substrate 51 and the barrier cover 52, a substantially rectangular lens opening 5a constituting a photographing frame of a camera is provided, and the lens barrier device 5 opens the lens opening 5a at the time of photographing to set a lens unit LU. The lens unit LU is configured to be closed during non-shooting, thereby protecting the lens unit LU. In addition, although the decorative ring plate for decoration which covers the hole and notch which are formed in the said peripheral part is stuck on the peripheral part of this barrier cover 52, this decorative ring board is abbreviate | omitting illustration here. .

  On the front surface of the barrier substrate 51, two barrier blades 6 and a drive lever 7 to be described later for driving these are disposed between the barrier cover 52 and the barrier substrate 52. Further, the cam cylinder 53 is rotated around the lens optical axis Lx in a required angular range with the movement of the straight advancing cylinder 3 in the above-mentioned extending and retracting direction of the lens optical axis at the time of storage. Thus, the barrier blade 6 is driven via the drive lever 7 to open and close the lens opening 5a.

  FIG. 4 (a) is a front view with the barrier cover 52 removed when the lens barrier device 5 has the lens opening 5a opened, and FIG. 4 (b) is a rear view. 5 (a) is a front view with the barrier cover 52 removed when the lens barrier device 5 blocks the lens opening 5a, and FIG. 5 (b) is a rear view. The barrier substrate 51 is generally formed in a disk shape, and two barrier blades 6 and two drive levers 7 are mounted on the front surface of the barrier substrate 51 at positions sandwiching the lens opening 5a in the radial direction. It is rotatably supported along the front surface 51 on the front surface. Since the barrier blade 6 and the drive lever 7 are point-symmetrical with respect to the center of the barrier substrate 51, that is, the lens optical axis Lx, they will be described by attaching the same reference numerals.

  The barrier blade 6 is formed by processing a thin metal plate or resin molding, but here, it is formed by resin molding. The barrier blade 6 includes a substantially triangular opening / closing portion 61 for opening and closing the lens opening 5a, and a relatively small triangular base portion 62 connected to one end of the opening / closing portion 61. It is pivotally supported by a support shaft 63 erected on a part of the circumference of the front surface of the barrier substrate 51 at the base end portion 62. The opening / closing portion 61 and the base end portion 62 can be rotated along the front surface of the barrier substrate 51 about the support shaft 63, as shown in FIG. 4A. The lens opening 5a is opened at the rotational position along the opening, and the lens opening 5a is closed as illustrated in FIG. 5A by being rotated clockwise from the rotational position toward the center of the barrier substrate 51. It is supposed to be. In the following description, the clockwise direction and the counterclockwise direction are directions when the lens barrier device 5 shown in FIG. 4A and FIG. 5A is viewed from the front.

  Here, the drive lever 7 is generally fan-shaped by a thin metal plate having a required strength, and a portion corresponding to the key of the drive lever 7 is adjacent to the proximal end 62 of the barrier blade 6. It is pivotally supported by a pin shaft 71 erected on a part of the cover substrate 51 at a position where it can be pivoted along the front surface of the barrier substrate 51 about the pin shaft 71. The drive lever 7 is disposed on the same plane along the front surface of the barrier blade 6 and the barrier substrate 51.

  As shown in FIG. 6, the drive lever 7 is partially formed in the clockwise direction as an arm piece 72, and a tip end portion 721 of the arm piece 72 is a base end portion of the barrier blade 6. It is in contact with part of 62. Here, in order to ensure the contact between the arm piece 72 and the base end portion 62, a contact rib 621 erected substantially perpendicularly to a part of the base end portion 62 is integrally formed. The tip end portion 721 of the arm piece 72 is in contact with the rising surface of the contact rib 621. FIG. 8 shows a perspective view as viewed from the diagonally opposite direction. At two locations of the drive lever 7, as shown in FIGS. 4, 5 and 6, spring retaining pieces 73 and 74 are formed to be bent backward (downward in FIG. 6, the same applies hereinafter). These spring retaining pieces 73 and 74 are located in the notch 511 provided in the barrier substrate 51. Of the spring retaining pieces 73 and 74, the spring retaining piece 73 on the clockwise direction centering on the pin shaft 71 is between the spring securing piece 512 provided on a part of the barrier substrate 51. An opening spring 75 is resiliently mounted as a first spring composed of a tension coil spring, and the biasing force of the opening spring 75 imparts a rotational behavior of the drive lever 7 in the clockwise direction.

  Also, a second spring consisting of a tension coil spring between the other counterclockwise spring retaining piece 74 and the spring retaining piece 64 provided on a part of the base end 62 of the barrier blade 6 As, the closing spring 76 is bullet-fitted. Due to the biasing force of the closing spring 76, the barrier blade 6 is imparted with a clockwise rotational behavior with respect to the drive lever 7. Although the barrier blade 6 is urged to rotate clockwise with respect to the drive lever 7 by the rotational habit due to the closing spring 76, the arm piece 72 of the drive lever 7 is the barrier blade 6 as described above. When being in contact with the contact piece 621 provided at the proximal end 62, the contact force causes the barrier blade 6 to be locked to rotate clockwise.

  Further, a cam pin 77 is projected rearward at a portion adjacent to the spring engaging piece 73 of the drive lever 7, and the cam pin 77 is disposed at a position facing the front edge of the cam cylinder 53. It is done. At the front edge of the cam cylinder 53, a cam projection 531 engaged with the cam pin 77 when the cam cylinder 53 is rotated about the lens optical axis Lx is integrally protruded forward. There is. The cam projection 531 is formed in a tapered shape whose end face in the counterclockwise direction is directed in the inner diameter direction. Therefore, as shown in FIG. 7, when the cam cylinder 53 is rotated about the lens optical axis, the cam pin 77 is engaged with the cam projection 531 provided on the cam cylinder 53, and the taper of the cam projection 531 Depending on the shape, the cam pin 77 is forcibly moved in the inner diameter direction, that is, in the center direction toward the lens optical axis Lx. Due to the forced movement of the cam pin 77 in the central direction, the drive lever 7 is turned counterclockwise against the biasing force of the open spring 75, and the arm piece 72 integral therewith is brought into contact with the contact rib 621 of the barrier blade 6. Thus, the barrier blade 6 is turned clockwise by the biasing force of the closing spring 76.

  Here, as shown in FIGS. 6, 7 and 8, in order to prevent the arm piece 72 of the drive lever 7 from being displaced forward (above the FIGS. 6, 7 and 8), A cantilevered restricting piece 513 is fixedly supported on the cover substrate 51 at a position covering the front side. That is, the drive lever 7 serves as a fulcrum as shown in FIGS. 9 (a) and 9 (b), respectively, as a front view of the vicinity of the drive lever 7 with the barrier cover 52 attached and its BB cross section. The head of the pin shaft 71 and the barrier substrate 51 sandwich the lens in the lens optical axis direction. Further, it is also regulated in the lens optical axis direction by the barrier substrate 51 and the regulation piece 513. Further, the closing spring 75 is internally provided in the notch 511 provided in the barrier substrate 51, and is accommodated within the range of the thickness of the barrier substrate 51. The same is true for the open spring 76.

  The cam cylinder 53 is supported in a state where the outer peripheral surface is in contact with the inner surface of the straight movement cylinder 3, that is, the inner surface of the barrier holding cylinder, as shown in FIG. Is integrally moved in the lens optical axis direction, but is held rotatably relative to the barrier holding cylinder 3 in the direction around the lens optical axis. In addition, the lens optical axis is disposed at two positions in the circumferential direction of the fixed frame 10 (see FIGS. 1, 2 and 3) disposed at the inner diameter position of the fixed cylinder 1 and fixedly supported by the fixed cylinder 1 or the camera body CB. The guide cams 12 are respectively projected in the outer diameter direction from a part of the linear liner 11 which is formed to project in the direction, and the inner surface of the cam cylinder 53 is extended in the direction inclined with respect to the lens optical axis direction A cam groove 532 in which the guide cam 12 is engaged is recessed. Thus, when the barrier holding barrel 3 is moved forward by the rotation of the rotary barrel 2, the cam barrel 53 is moved integrally with the cam barrel 53 in the direction of the lens optical axis. The cam cylinder 53 is rotated relative to the barrier holding cylinder 3 about the lens optical axis by the cam engagement. In this example, when the barrier holding cylinder 3 is drawn out, it is turned clockwise in FIG.

  According to the lens barrier device of this embodiment, the cam groove 532 of the cam cylinder 53 is engaged with the guide cam 12 when the lens unit LU shown in FIG. 1 is accommodated in the camera body CB. The cam cylinder 53 is in the counterclockwise rotated position. In this rotational position, as shown in FIGS. 5 and 7, the cam projection 531 of the cam cylinder 53 is engaged with the cam pin 77 of the drive lever 7, and the cam pin 77 is forcibly moved in the inner diameter direction. Therefore, as shown by arrows P2 and Q2 in FIG. 5A, the drive lever 7 is pivoted counterclockwise around the pin shaft 71 against the biasing force of the open spring 75 (P2). The arm piece 72 integral therewith is at a position retracted from a position retracted counterclockwise from the contact position of the barrier blade 6 with the contact rib 621. Therefore, the barrier blade 6 is not locked to rotate clockwise by the arm piece 72, and the barrier blade 6 is rotated clockwise by the biasing force of the closing spring 76 (Q2). Each opening and closing portion 61 of the blade 6 closes the lens opening 5 a by half, so that the lens opening 5 a is completely closed.

  At this time, as shown in FIG. 11, the cam groove 532 provided on the cam cylinder 53 is engaged with the guide cam 12 in a state in which the lens unit LU is accommodated in the camera body CB, as shown in FIG. The portion 532a is extended in a direction parallel to the lens optical axis direction over a predetermined length. Therefore, the cam cylinder 53 is not rotated even if the cam cylinder 53 is slightly moved in the lens optical axis direction when the lens unit LU is stored, and the cam projection 531 forcibly rotates the cam pin 77, that is, the drive lever 7. It is possible to maintain the closed state of the lens opening 5a by the barrier blade 6 while maintaining the state in which the lens blade 5 is closed. Therefore, even if the storage position of the lens unit LU in the camera body CB is deviated in the lens optical axis direction due to the tolerance existing in the lens unit LU or the design / production error, the lens opening 5a is reliably closed. can do.

  On the other hand, when the rotary cylinder 2 is rotated and the lens unit LU is fed out from the camera body CB as shown in FIG. 2, the cam cylinder 53 is engaged by the cam groove 532 of the cam cylinder 53 and the guide cam 12 It is turned clockwise. As a result, as shown in FIGS. 4 and 6, the cam projection 531 of the cam cylinder 53 is disengaged from the cam pin 77 of the drive lever 7 and released from the state of forced rotation. Therefore, as indicated by P1 and Q1 in FIG. 4A, the drive lever 7 is rotated clockwise by the biasing force of the open spring 75 (P1). As a result, the arm piece 72 of the drive lever 7 abuts on the abutment rib 621 of the barrier blade 6, and the base end portion 62 is forcibly rotated counterclockwise against the biasing force of the closing spring 76. Therefore, the barrier blade 6 is pivoted counterclockwise (Q1), and the respective open / close portions 61 of the pair of barrier blades 6 are retracted from the position closing the lens opening 5a to open the lens opening 5a.

  At this time, the arm piece 72 of the drive lever 7 abuts on the base end 62 of the barrier blade 6 by the biasing force of the open spring 75 to rotate the barrier blade 6. The contact force is great. There is a possibility that the drive lever 7 may be displaced or deformed in the plate thickness direction by the contact force, and the arm piece 72 and the base end 62 may not be properly in contact due to the displacement or deformation. Be However, since the restriction piece 513 is disposed along the front surface side of the arm piece 72 here, the arm piece 72 is prevented from being displaced or deformed in the plate thickness direction. Also, since the abutment rib 621 erected in the thickness direction exists at the portion of the proximal end 62 where the arm piece 72 abuts, the arm piece 72 is slightly displaced and deformed in the thickness direction. However, the contact state with the contact rib 621 is not impaired. Thereby, the lens opening 5a can be reliably opened, and the open state can be stably held.

  As described above, the lens barrier device 5 has the lens holding frame 42, that is, the barrier holding cylinder 3 consisting of a straight moving cylinder disposed on the outer periphery of the lens cylinder 4, and the lens barrier device 5 is configured at the front end Therefore, it is possible to dispose the barrier blade 6 which is a main component of the lens barrier device 5 within the area of the outer diameter of the barrier holding cylinder 3 having a diameter larger than that of the lens cylinder 4. A large movable range of the barrier blade 6 can be secured. Thereby, the barrier blade 6 can be configured by a pair of plate members, and the drive lever 7 for driving the barrier blade 6 can also be configured by a pair of plate members. It can be reduced to simplify the configuration. Furthermore, in the lens barrier device 5, the barrier blade 6 and the drive lever 7 each formed of a thin plate member are disposed in a minute gap in the lens optical axis direction sandwiched between the barrier cover 52 and the barrier substrate 51. Since the barrier blade 6 and the drive lever 7 are disposed in the same plane intersecting the lens optical axis Lx, the dimension in the lens optical axis direction occupied in the lens barrier device 5 is a plate of a substantially thin plate It can be configured as a dimension corresponding to the thickness. Further, since the open spring 75 and the close spring 76 for rotationally biasing the barrier blade 6 and the drive lever 7 are disposed in the notch 511 provided in the barrier substrate 51, these springs 75 and 76 are provided. The dimension in the lens optical axis direction can be accommodated within the thickness dimension of the barrier substrate 51, and the dimension in the lens optical axis direction is not increased by the springs 75 and 76. From the above, while the diameter reduction of the barrier device 5 to the barrier holding cylinder 3 is realized, as shown in FIG. 2, the dimension L1 in the lens optical axis direction in which the lens cylinder 4 in the barrier holding cylinder 3 can move. Can be secured to the maximum.

  Further, since the lens barrier device 5 is disposed at the front end of the barrier holding barrel 3 disposed on the outer periphery of the lens barrel 4, the outer diameter dimension of the lens barrel 4 and the dimension in the lens optical axis direction are increased. In addition, the weight of the lens barrel 4 does not increase unnecessarily, and the lens drive can be performed quickly and with low power consumption. Further, the cam cylinder 53 for driving the drive lever 7 or the barrier blade 6 of the lens barrier device 5 is constituted by a single cylindrical member along the inner peripheral surface of the barrier holding cylinder 3, and this cam cylinder 53 is Since the cam cylinder 53 is disposed at the outer peripheral position of the lens barrel 4, the cam barrel 53 hardly overlaps the barrier blade 6 or the drive lever 7 in the lens optical axis direction, and the diameter dimension of the lens barrier device 5 is reduced. be able to. Further, the cam barrel 53 hardly overlaps the lens barrel 4 as viewed in the lens optical axis direction, and the diameter of the barrier holding barrel 3 can be suppressed to the minimum size also from this surface.

  Here, although the description is omitted in the embodiment, in order to reduce the contact resistance at the contact surface of the tip end portion 721 of the arm piece 72 of the drive lever 7 and the contact rib 621 of the barrier blade 6 with which this is abutted. Preferably, the contact surface is subjected to a surface treatment to be a lubricating surface. For example, the contact surface of the contact rib 621 may be coated or plated with a highly lubricious film. By applying such surface treatment, in particular, the arm piece 72 is rotated integrally with the drive lever 7 by the biasing force of the opening spring 75, and the contact of the arm piece 72 resists the biasing force of the closing spring 76. This configuration is advantageous in reducing the contact resistance between the tip portion 721 of the arm piece 72 and the contact rib 621 when opening the blade 6 and reducing the biasing force of the closing spring 76 to achieve downsizing.

  Moreover, although the barrier blade | wing 6 is formed with resin in embodiment, and the drive lever 7 is formed with a metal plate, it is not limited to these materials. However, if the barrier blade 6 is resin-molded as in the embodiment, the contact rib 621 can be integrally formed, which is preferable in terms of facilitating the manufacture and reducing the weight. The abutment rib may be provided on the drive lever to obtain a reliable abutment with the barrier blade. In addition, if the drive lever 7 is formed of a metal plate, in order to obtain necessary strength, in particular, strength capable of withstanding internal stress that occurs when the barrier blade 6 is pivoted in the opening direction when it is forcibly pivoted by the cam cylinder 53. Is preferable in reducing the dimension in the lens optical axis direction of the lens barrier device.

  In the embodiment, the restricting plate 513 for suppressing displacement or deformation of the drive lever 7 in the plate thickness direction is integrally provided on the barrier substrate 51, but in the case where the drive lever 7 has sufficient strength The restriction plate 513 may be omitted.

The present invention is applied to the lens barrel constructed as a lens unit of a method of extending the camera body from the camera body, but the outer cylinder of the lens unit is fixed to the camera body, and in this outer cylinder, the lens cylinder is in the lens optical axis direction The present invention can be similarly applied as a lens unit configured to be moved to. In this case, the outer cylinder may be configured as a barrier holding cylinder, and the lens barrier device may be formed at the front end of the outer cylinder.
The present invention can reduce the dimension in the lens optical axis direction of the lens barrier device as compared with the configuration in which the barrier blade and the drive lever are overlapped in the lens optical axis direction. As a result, it is possible to increase the amount of movement of the lens barrel in the lens optical axis direction within the barrier holding barrel while suppressing the dimension of the lens barrel in the lens optical axis direction. Further, since the lens barrier device is formed on the barrier holding cylinder disposed on the outer periphery of the lens cylinder, the outer diameter dimension for disposing the barrier blade can have a margin, and the barrier blade can be configured with a small number of lenses It is possible to reduce the number of components of the barrier device and simplify the configuration. For example, by configuring the barrier blade and the drive lever with a pair of plate members, the number of these components can be reduced, the configuration can be simplified, and thinning in the lens optical axis direction can be achieved.
According to the present invention, since the cam cylinder is disposed along the inner peripheral surface of the barrier holding cylinder and rotates the drive lever when it is rotated around the lens optical axis, the inner peripheral surface of the barrier holding cylinder is It is sufficient to provide the cam cylinder, and the outer diameter of the barrier holding cylinder can be reduced to a size close to the outer diameter of the lens cylinder. As a result, it is possible to configure a lens barrier device in which the outer diameter dimension of the barrier holding cylinder is made as small as possible. Further, since the cam cylinder hardly overlaps the barrier blade and the drive lever in the lens optical axis direction, it is also advantageous in reducing the dimension of the lens barrier device in the lens optical axis direction.
According to the present invention, the first and second springs for providing the drive lever with rotational behavior and the second spring for providing the barrier blade with rotational behavior are provided. In this embodiment, the spring is not protruded from the barrier substrate in the lens optical axis direction, and the dimension in the lens optical axis direction can be further reduced. Further, the barrier substrate includes a restriction piece for preventing displacement and deformation of the drive lever in the plate thickness direction, and the barrier substrate is configured by sandwiching the drive lever between the restriction piece and the barrier substrate. Thus, the increase in the thickness dimension of the lens barrier device can be suppressed, and the dimension in the lens optical axis direction of the lens barrier device can be reduced.
According to the present invention, the drive lever is provided with the contact piece to be in contact with the barrier blade, and one of the contact portions of the contact piece and the barrier blade is provided with the contact rib whose dimension in the plate thickness direction is enlarged. By providing this, a stable contact state between the drive lever and the barrier blade can be ensured, and a stable opening / closing operation by the barrier blade can be performed. In addition, at least one of the contact surfaces of the contact piece and the barrier blade is subjected to a surface treatment such as coating, plating, etc., to enhance lubricity, so that the frictional force etc. This makes it possible to reduce the size of the spring and the drive lever, and to make the lens barrier device smaller.

  The present invention is effective when employed in a lens barrier device for opening and closing a lens opening provided on the front surface of a lens barrel, a lens barrel and a camera.

CB Camera body LU Lens unit 1 Fixed cylinder 2 Rotation cylinder 3 Straight movement cylinder (barrier holding cylinder)
Reference Signs List 4 lens barrel 5 lens barrier device 5a lens aperture 6 barrier blade 7 drive lever 41 motor frame 42 lens holding barrel 51 barrier substrate 511 notch 513 restricting piece 52 barrier cover 53 cam barrel 531 cam protrusion 532 cam groove 61 opening / closing portion 62 base end Section 621 Abutment rib 72 Arm piece (Abutment piece)
75 Open spring (first spring)
76 closing spring (second spring)

Claims (14)

A lens barrier device provided in a barrier holding cylinder disposed on the outer periphery of a lens cylinder, the barrier blade for opening and closing a lens opening provided in the barrier holding cylinder, and a drive lever for opening and closing the barrier blade Are disposed on the same plane perpendicular to the lens optical axis, and the first spring for pivotally urging the drive lever against the barrier holding cylinder, and the barrier blade for pivoting the drive lever relative to the drive lever A lens barrier device comprising a second spring for biasing .   A barrier substrate and a barrier cover which are disposed in the barrier holding cylinder and arranged close to each other in the lens optical axis direction, and the barrier blade and the drive lever are lens light configured between the barrier cover and the barrier substrate The lens barrier device according to claim 1, wherein the lens barrier device is disposed in an axial minute gap.   The barrier blade is a pair of plate members disposed symmetrically with respect to the lens optical axis and opening and closing the lens opening according to a change in rotational position on the surface, and the drive lever is provided for each of the barrier blades. 3. The lens barrier device according to claim 1, wherein the lens barrier device is provided with a pair of plate members that are provided for the lens and change the rotational position of each barrier blade according to a change in the rotational position of the lens.   The cam barrel which is arrange | positioned along the inner peripheral surface of the said barrier holding cylinder, and which rotates the said drive lever when it is rotated about a lens optical axis is provided, either of 1 thru | or 3 characterized by the above-mentioned. Lens barrier device as described. Before Symbol first and second spring lens barrier device according to any one of claims 2 to 4, characterized in that it is furnished in a notch provided in the barrier substrate.   The first spring pivotally biases the drive lever against the barrier substrate, and the second spring pivotally biases the barrier blade against the drive lever, and the cam cylinder drives the drive The lever is forcibly rotated in the direction opposite to the rotational biasing of the first spring, and the drive lever applies the biasing force of the first spring to the biasing force of the second spring. The barrier blade is urged against the biasing force of the first spring by the cam barrel and is urged against the biasing force of the first spring. 6. The lens barrier device according to claim 5, wherein the lens opening is pivoted in the closing direction according to.   The barrier substrate includes a control piece for preventing displacement and deformation of the drive lever in the plate thickness direction, and the drive lever is sandwiched between the control piece and the barrier substrate. 2. The lens barrier device according to any one of 2 to 6.   The drive lever is provided with a contact piece that contacts the barrier blade, and one of the contact portions between the contact piece and the barrier blade is provided with a contact rib whose dimension in the plate thickness direction is increased. The lens barrier device according to claim 6, wherein the lens barrier device is characterized.   The drive lever is provided with a contact piece to be in contact with the barrier blade, and at least one of the contact surface of the contact piece and the barrier blade is subjected to surface treatment such as painting, plating, etc. for enhancing the lubricity. The lens barrier device according to claim 6, wherein the lens barrier device is provided.   The lens barrier device according to any one of claims 1 to 9, wherein the barrier blade is made of resin and the drive lever is made of metal.   The barrier holding cylinder is configured to be fed out from the storage position of the camera body, and the cam cylinder is extended about the lens optical axis with the storage operation, and the barrier blade is rotated by the rotation at the time of extension. The lens barrier device according to any one of claims 4 to 10, wherein the lens aperture is opened and the lens aperture is closed by the barrier blade by rotation upon storage.   The lens barrier device according to any one of claims 1 to 11, wherein the lens barrel is configured to be moved in a lens optical axis direction in the barrier holding barrel.   A lens barrel comprising the lens barrier device according to any one of claims 1 to 12.   A camera comprising the lens barrel according to claim 13.

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