JP2009175433A - Barrier mechanism, lens device and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decrease a load on a driving source and reduce consumption power. <P>SOLUTION: A barrier mechanism 120 is configured such that: driving force from a power transmission mechanism is transmitted to barrier blades 202 to 205 disposed so as to be freely displaced between an opening position for making outside light incident on an optical path and a closing position for blocking the incidence of outside light on the optical path; and the barrier blades 202 to 205 are displaced from the opening position to the closing position and from the closing position to the opening position. The barrier mechanism 120 is provided with a torsion spring 412 that composes part of a driving mechanism, presses barrier blades 202 to 205 in the opening position to the opening position side and also presses the barrier blades 202 to 205 in the closing position to the closing position side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a barrier mechanism, a lens apparatus, and an imaging apparatus that cover an objective lens of a camera at the time of non-imaging to protect the objective lens from external impacts and contamination.

  Conventionally, there has been a lens apparatus and an imaging apparatus provided with a barrier mechanism. The barrier mechanism includes a barrier blade that covers the objective lens, a drive mechanism that drives the barrier blade, etc., and driving the barrier blade by the drive mechanism opens the objective lens to the outside or blocks the objective lens from the outside. To do.

  The barrier mechanism includes, for example, a biasing member that biases the barrier blade in a direction to block the objective lens from the outside, and the objective lens is blocked from the outside by the biasing force of the biasing member (the barrier blade is closed) Have been able to be maintained stably. In such a barrier mechanism, the barrier blade is driven to open the objective lens to the outside by applying a driving force against the biasing force of the biasing member to the barrier blade using a predetermined power transmission member. To do.

  Some of such barrier mechanisms include another urging member that can drive the power transmission member when an urging force equal to or greater than the urging force that urges the barrier blades is applied. When driving the blade in the opening direction, there is one in which the barrier blade is stably operated by applying a driving force against the urging force of the other urging member to the power transmission member (for example, (See Patent Documents 1 and 2 below.)

JP 2003-195393 A JP 2003-057705 A

  However, in the conventional techniques including Patent Documents 1 and 2 described above, since the urging force in the direction of blocking the objective lens from the outside is constantly applied to the barrier blade, the objective lens is opened to the outside. In some cases, a driving force greater than the urging force of the urging member against the urging force of the urging member is required.

  An object of the present invention is to provide a barrier mechanism, a lens device, and an imaging device that can reduce a load applied to a driving source and reduce power consumption in order to eliminate the above-described problems caused by the related art. .

  In order to solve the above-described problems and achieve the object, the barrier mechanism according to the present invention is displaceable between an open position where external light is incident on the optical path and a closed position where the external light is blocked from entering the optical path. And a biasing member. The barrier blade is transferred from the open position to the closed position side by transmitting a driving force from a driving source to the barrier blade via the biasing member. A driving mechanism for displacing from the closed position toward the open position, and the biasing member biases the barrier blade at the open position toward the open position and causes the barrier blade at the closed position to move toward the open position. It is characterized by urging toward the closed position.

  According to this invention, the same urging member can be used to urge the barrier blades in the open position toward the open position and urge the barrier blades in the closed position toward the closed position.

  Further, the barrier mechanism according to the present invention includes a barrier blade that is displaceable between an open position where external light is incident on the optical path and a closed position where the external light is blocked on the optical path, and an urging member The barrier blade is displaced from the open position to the closed position side and from the closed position to the open position side by transmitting a driving force from a drive source to the barrier blade through the biasing member. A driving mechanism, and the biasing member biases the barrier blade toward the closed position when the barrier blade is displaced toward the closed position, and also when the barrier blade is displaced toward the open position. The barrier blade is provided so as to urge the barrier blade toward the opening position.

  According to this invention, the same biasing member is used to bias the barrier blade toward the closed position when the barrier blade is displaced toward the closed position, and to open the barrier blade when the barrier blade is displaced toward the open position. Can be biased to the side.

  Moreover, the barrier mechanism according to the present invention is characterized in that, in the above-described invention, the urging member causes substantially the same urging force to act on the barrier blades in the closed position and the open position. According to this invention, the driving force for displacing the barrier blade to the open position side and the driving force for displacing the barrier blade to the closed position side can be made substantially the same.

  In the barrier mechanism according to the present invention, in the above invention, the urging member switches the urging direction to the closed position side during the displacement of the barrier blade from the open position to the closed position. The biasing direction is provided to be able to be switched to the opening position side during the displacement from the closed position to the opening position.

  According to this invention, by switching the urging direction in the middle of the displacement of the barrier blade, the urging force until switching is released, and the urging force in the displacement direction can be obtained. Further, according to the present invention, the same biasing member can be used to bias the barrier blade at the open position toward the open position and bias the barrier blade at the closed position toward the closed position.

  In the barrier mechanism according to the present invention, in the above invention, the drive mechanism is provided so as to be reciprocally movable in the vicinity of the rotation shaft to which the barrier blade is rotatably connected and the rotation shaft. A first boss that generates the urging force on the urging member by reciprocating and a barrier blade are provided so that the urging member abuts when the first boss reciprocates. The second boss that receives the urging force from the urging member, and the both ends that are wound around the rotation shaft and extend so as to face each other with the first boss and the second boss in between. A torsion spring as an urging member, and the torsion spring is configured such that when the first boss comes into contact with one end side with the forward movement of the first boss, the other end side is set to the second side. The first boss is moved back When the first boss is not in contact with the other end side, the driving force from the drive source is transmitted to the barrier blade by bringing the one end side into contact with the second boss. Features. According to the present invention, the above-described invention can be realized with a simple configuration.

  Further, the barrier mechanism according to the present invention is the above-described invention, wherein the straight line passing through the rotary shaft and the second boss at the open position and the straight line passing through the rotary shaft and the first boss at the closed position are provided. It is characterized in that the angle between the opening position and the closing position is the same. According to the present invention, substantially the same urging force can be applied to the barrier blades in the open position and the closed position only by assembling without performing adjustment work.

  In addition, a lens apparatus according to the present invention is characterized in that the above-described barrier mechanism is incorporated and an optical member that forms an optical path through which external light is incident on the image sensor. According to this invention, the optical member can be protected by the barrier mechanism.

  An image pickup apparatus according to the present invention includes an image pickup element and the lens device described above. According to the present invention, the optical member in the lens device can be protected by the above-described barrier mechanism during non-imaging.

  According to the barrier mechanism, the lens device, and the imaging device according to the present invention, the excessive driving force can be reduced without applying the excessive driving force, or the applied driving force can be used as the displacement of the barrier blade. It can be used efficiently, and the load on the drive source can be reduced.

  Exemplary embodiments of a barrier mechanism, a lens apparatus, and an imaging apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings.

(Schematic configuration of the lens device)
First, a schematic configuration of a lens apparatus according to an embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing a schematic configuration of a lens apparatus according to an embodiment of the present invention. In FIG. 1, a lens apparatus 100 according to an embodiment of the present invention includes a lens barrel 101. The lens barrel 101 includes a fixed cylinder 102, a cam cylinder 103, and a rectilinear guide cylinder 104. The fixed cylinder 102 is attached to a mount 105, and is attached to the main body of an imaging device (not shown) via the mount 105.

  An imaging element is disposed in the main body of the imaging apparatus. The image sensor photoelectrically converts external light received through the lens device 100 and outputs an electrical signal corresponding to the amount of incident light. Specifically, the imaging element is realized by, for example, a CCD. The cam cylinder 103 is slidably connected to the fixed cylinder 102 along the axial direction of the optical axis C (hereinafter referred to as “optical axis direction”). Since the configuration in which the cam cylinder 103 is connected to the fixed cylinder 102 so as to be slidable in the optical axis direction is a known technique, description thereof is omitted.

  In the lens barrel 101, a first lens group 106, a second lens group 107, and a third lens group 108 are provided. The first lens group 106 includes a G01 lens 109 and a G02 lens 110, and is connected to the cam cylinder 103 via a first lens group frame 111. The first lens group frame 111 is connected in a state of being suspended from the cam cylinder 103 by a first group cam pin 111 a, so that the first lens group frame 111 is movable in the optical axis direction with respect to the cam cylinder 103. Has been.

  The second lens group 107 includes a G3 lens 112, a G4 lens 113, and a G5 lens 114, and is connected to the cam cylinder 103 via a second lens group frame 116. The second lens group frame 116 is connected in a state suspended from the cam cylinder 103 by a projection 117 provided on the second lens group frame 116, and is thereby movable in the optical axis direction with respect to the cam cylinder 103. Linked in state.

  The configuration in which the first lens group frame 111 and the second lens group frame 116 are connected to the cam cylinder 103 so as to be movable in the optical axis direction can be realized by using various known techniques, and thus description thereof is omitted. The third lens group 108 includes a G6 lens 115. The G6 lens 115 is provided in the lens barrel 101 while being held by a third group frame (focus frame) 115a. The third group frame 115a (G6 lens 115) is connected in a suspended state to a mount or a guide pole (not shown) protruding from the second lens group frame 116, and is driven in the optical axis direction by a drive source such as a motor. It is connected in a movable state.

  In the cam cylinder 103, an iris shutter 118 is provided between the first lens group 106 and the second lens group 107. The iris shutter 118 adjusts the amount of light that passes through the first lens group 106 and enters the second lens group 107. Since the iris shutter 118 can be realized using various known techniques, description thereof is omitted. A plurality of metal rings 119 are provided on the subject side (first lens group 106 side) of the cam cylinder 103. By providing the metal ring 119, the design of the lens device 100 can be improved.

  A barrier mechanism 120 is provided on the subject side of the cam cylinder 103 (on the first lens group 106 side relative to the second lens group 107). The barrier mechanism 120 is driven in conjunction with the other barrel part. Specifically, the barrier mechanism 120 opens the first lens group 106 to the outside so that an image can be captured, or covers the first lens group 106 to protect the first lens group 106.

(Configuration of barrier mechanism 120)
Next, the barrier mechanism 120 according to the embodiment of the present invention will be described. 2 and 3 are perspective views showing the barrier mechanism 120 according to the embodiment of the present invention. 2 shows a closed state of the barrier mechanism 120, and FIG. 3 shows an opened state of the barrier mechanism 120.

  2 and 3, the barrier mechanism 120 includes a barrier base 201, a plurality of barrier blades 202 to 205, a barrier opening / closing ring (see reference numeral 408 in FIGS. 4 and 5), and a barrier cover 206. I have. In this embodiment, four barrier blades 202 to 205 are provided. The number of barrier blades is not limited to four, and is not limited to an even number.

  The barrier base 201 includes an opening 207, and the barrier cover 206 includes an opening 301. Each of the openings 207 and 301 opens the optical path in the lens device 100, and the barrier blades 202 to 205 that allow external light to enter the first lens group 106 (objective lens) can be rotated with respect to the barrier base 201. The barrier cover 206 is fixed with respect to the barrier base 201.

  The barrier cover 206 covers the barrier blades 202 to 205, protects the barrier blades 202 to 205 from the outside, and allows the barrier blades 202 to 205 to rotate between the barrier base 201 and the barrier blades 202 to 205. Lifting from the barrier base 201 is prevented.

  4 and 5 are exploded perspective views showing the barrier mechanism 120 according to the embodiment of the present invention. 4 shows a state in which the barrier mechanism 120 in the closed state shown in FIG. 2 is viewed from the subject side, and FIG. 5 shows a state in which the barrier mechanism 120 in the closed state shown in FIG. 2 is viewed from the image plane side. Is shown.

  4 and 5, the barrier base 201 includes a rotation shaft 401 to which the barrier blades 202 to 205 are rotatably attached. The rotating shaft 401 is provided with a torsion spring 412 as an urging member. The torsion spring 412 is wound around the rotation shaft 401 so that both end portions 412 a and 412 b extend in the radial direction of the rotation shaft 401, and the rotation shaft 401 is centered on the rotation shaft 401. It is relatively rotatable.

  Each of the barrier blades 202 to 205 includes a shaft hole 402 into which the rotation shaft 401 is inserted. When the driving force is transmitted from the power transmission mechanism, the barrier blades 202 and 203 rotate from the open position toward the closed position or from the closed position toward the open position.

  The power transmission mechanism includes a motor as a driving source and various mechanisms for transmitting the driving force of the motor. The various mechanisms can be realized by, for example, a rotating body such as a gear connected to a rotating shaft of a motor, and a gear, pulley, belt, or the like that transmits the rotational force of the rotating body. Since it is a well-known technique, illustration and description of the power transmission mechanism are omitted.

  The barrier blades 202 and 203 include a protrusion 403 and a boss 404 as a second boss protruding toward the barrier base 201 side. The protrusion 403 is provided on the barrier blades 204 and 205 side, and protrudes on the barrier blades 204 and 205 side. The boss 404 is provided on the barrier base 201 side and protrudes on the barrier base 201 side.

  The protrusion 403 is positioned inside the notch 405 provided in the barrier blades 204 and 205 and at a position that interferes with the rotation trajectory of the barrier blades 204 and 205. The barrier blades 204 and 205 are urged by the protrusions 403 when the barrier blades 202 and 203 rotate, and rotate in the same direction as the rotation direction of the barrier blades 202 and 203.

  When the barrier blades 202 and 203 are rotated from the closed position to the open position and from the open position to the closed position, the locking claws 406 are formed between the barrier blades 204 and 205 between the barrier cover 206 and the barrier base 201. Suppresses rattling. Thereby, the barrier blades 204 and 205 can be opened and closed stably.

  Further, the barrier blades 204 and 205 include a guide rib 407 and a guide rib 500. The guide rib 407 guides the rotational positions of the barrier blades 204 and 205 that rotate as the barrier blades 202 and 203 rotate. The guide rib 500 guides the rotational positions of the barrier blades 202 and 203 with respect to the barrier blades 204 and 205. The guide rib 500 is provided along the outer peripheral locus that is the outermost side of the barrier blades 202 and 203 that rotate about the rotation shaft 401. The barrier blades 202 to 205 can be stably rotated by the guide ribs 407 and 500.

  The barrier base 201 includes guide ribs 416. The guide rib 416 is provided on the barrier base 202 on the side of the barrier blades 202 and 203 and along the outer peripheral locus that is the outermost side of the barrier blades 202 and 203 that rotate about the rotation shaft 401. The guide rib 416 guides the rotational position of the barrier blades 202 and 203. The rotation positions of the barrier blades 202 and 203 are guided from both sides in the optical axis direction by the guide ribs 416 and 500, whereby the barrier blades 202 to 205 can be stably rotated.

  The barrier mechanism 120 includes a barrier opening / closing ring 408 as an opening / closing member attached to the barrier base 201. The barrier opening / closing ring 408 includes an opening 409 that opens an optical path in the lens device 100. The barrier opening / closing ring 408 is provided to be rotatable relative to the barrier base 201 around the optical axis C in the optical path.

  The barrier opening / closing ring 408 includes a power transmission rib 410 to which a driving force is transmitted from the power transmission mechanism, and rotates about the optical axis C when the driving force is transmitted from the power transmission mechanism. . The barrier opening / closing ring 408 rotates in the direction of arrow B in FIG. 4 or the direction of arrow A in FIG. 5 according to the direction of the driving force transmitted from the power transmission mechanism (the direction of rotation of the motor).

  The barrier opening / closing ring 408 includes a boss 411 as a first boss protruding toward the barrier base 201 side. The torsion spring 412 is disposed in a state in which both end portions 412a and 412b extend so as to face each other with the boss 411 and the boss 404 therebetween. The torsion spring 412 exerts an urging force in a direction against the applied external force when an external force is applied in a direction in which the distance between the both end portions 412a and 412b is increased.

  When the barrier opening / closing ring 408 is rotated by transmitting the driving force from the power transmission mechanism via the power transmission rib 410 as described above, the boss 411 is moved along the optical axis along with the rotation of the barrier opening / closing ring 408. It rotates on the circumference centering on C. The boss 411 rotates so as to reciprocate on the circumference around the optical axis C in the vicinity of the rotation shaft 401 in accordance with the rotation direction of the barrier opening / closing ring 408.

  The driving force transmitted from the power transmission mechanism is transmitted to the barrier blades 202 and 203 by the power transmission rib 410, the boss 411, the torsion spring 412, and the boss 404, and the barrier blades 202 and 203 are rotated by the transmitted driving force. . In this embodiment, a driving mechanism is realized by the power transmission rib 410, the boss 411, the torsion spring 412 and the boss 404.

  The barrier opening / closing ring 408 includes a protrusion 414 to which one end of a tension spring 413 serving as a second urging member is locked. The other end of the tension spring 413 is locked to a locking portion 501 provided on the barrier base 201. In this embodiment, the second urging member is realized by the tension spring 413, but the present invention is not limited to this. Instead of the tension spring 413, an elastic member such as rubber may be used to realize the second urging member.

  The tension spring 413 positions the barrier opening / closing ring 408 in an open state by pulling the projection 414 toward the locking portion 501 by a contraction force that maintains the contracted state. The barrier opening / closing ring 408 rotates in the arrow B direction when a driving force equal to or greater than the urging force of the tension spring 413 is applied.

(Opening and closing operation of the barrier mechanism 120)
Next, the opening / closing operation of the barrier mechanism 120 will be described. FIGS. 6A, 6B, 6A, and 7B are explanatory diagrams illustrating the opening / closing operation of the barrier mechanism 120. FIGS. 6A and 6B show the closed state of the barrier mechanism 120, and FIGS. 7A and 7B show the opened state of the barrier mechanism 120.

  6-1, FIG. 6-2, FIG. 7-1 and FIG. 7-2 show a state in which the barrier cover 206 and the barrier blades 204 and 205 are removed. In FIG. 6-1, FIG. 6-2, FIG. 7-1, and FIG. 7-2, the rotating shaft 401 and some members around it are indicated by solid lines regardless of the stacking relationship of the members. .

  The boss 411 abuts on a torsion spring 412 provided on the boss 401 during rotation, and transmits the driving force transmitted from the power transmission mechanism to the barrier blades 202 and 203 via the torsion spring 412. When the barrier opening / closing ring 408 rotates in the direction of arrow A, the boss 411 abuts against one end portion 412a of the both end portions 412a and 412b, and connects the torsion spring 412 to the arrow a in FIGS. 6-1 and 6-2. Rotate in the direction (see FIGS. 8-1 and 8-2).

  When the torsion spring 412 rotates in the direction of arrow a, the torsion spring 412 rotates the boss 404 in the direction of arrow a by the other end portion 412b of the both end portions 412a and 412b of the torsion spring 412. As a result, the barrier blades 202 and 203 rotate from the closed position to the open position side with the rotation shaft 401 as the rotation center, and the barrier blades 204 and 205 open from the closed position as the barrier blades 202 and 203 rotate. The barrier mechanism 120 is opened by rotating in the position side direction.

  On the other hand, the boss 411 contacts the other end portion 412b when the barrier opening / closing ring 408 rotates in the direction of arrow B, and rotates the torsion spring 412 in the direction of arrow b in FIGS. 7-1 and 7-2. . When the torsion spring 412 rotates in the arrow b direction, the torsion spring 412 rotates the boss 404 in the arrow b direction by the one end portion 412a.

  As a result, the barrier blades 202 and 203 rotate from the open position to the close position side with the rotation shaft 401 as the rotation center, and the barrier blades 204 and 205 close from the open position as the barrier blades 202 and 203 rotate. The barrier mechanism 120 is closed by rotating in the position side direction.

  The torsion spring 412 applies a biasing force in a direction against the rotation direction of the boss 411 to the boss 411 when the boss 411 rotates from the closed position to the open position side direction or from the open position to the close position side direction. . This biasing force acts as a biasing force that biases the boss 404 in the rotational direction of the boss 411 when the torsion spring 412 contacts the boss 404.

  When the boss 411 moves to the open position or the closed position, a biasing force that biases the boss 404 toward the open position or the closed position is obtained. As described above, the urging force of the torsion spring 412 is switched according to the position of the boss 411 between the urging target and the magnitude of the urging force with respect to the urging target.

(Position relationship between the rotation shaft 401, the boss 404, and the boss 411)
Next, the positional relationship among the rotation shaft 401, the boss 404, and the boss 411 will be described. 8A and 8B are explanatory diagrams illustrating the positional relationship among the rotation shaft 401, the boss 404, and the boss 411. 8A and 8B, the rotation shaft 401, the boss 404, and the boss 411 are provided in a positional relationship such that the angle α1 and the angle α2 are equal.

  The angles α1 and α2 are a straight line that passes through the contact point between the boss 411 and the one end portion 412a and the center of the rotation shaft 401, a straight line that passes through a contact point between the boss 404 and the other end portion 412b and the center of the rotation shaft 401, Is the angle formed by The angle α1 is formed when the barrier blades 202 to 205 are positioned at the closed position, and the angle α2 is formed when the barrier blades 202 to 205 are positioned at the open position.

  As described above, according to this embodiment, the driving force for displacing the barrier blades 202 to 205 to the opening position side and the driving force for displacing the barrier blades 202 to 205 to the closing position side can be made substantially the same. Accordingly, the driving force required for the displacement of the barrier blades 202 to 205 can be applied to the barrier blades 202 to 205 without applying an excessive driving force. Compared with the case where an urging force biased toward the closed position is applied, the load applied to the motor serving as the drive source can be reduced.

  Moreover, according to this embodiment, by switching the urging direction in the middle of the displacement of the barrier blades 202 to 205, the urging force until switching is released, and the urging force in the displacement direction can be obtained. As a result, the load on the motor can be reduced.

  Furthermore, according to this embodiment, using one torsion spring 412, the barrier blades 202 to 205 in the open position are biased toward the open position, and the barrier blades 202 to 205 in the closed position are applied to the close position. You can Thereby, the number of parts can be reduced, and the load on the motor can be reduced with a simple configuration.

  Further, according to this embodiment, the biasing direction is switched in the middle of the displacement of the barrier blades 202 to 205 by designing the positional relationship among the rotation shaft 401, the boss 404 and the boss 411 as described above. Therefore, the load on the motor can be reduced with a simple configuration. Accordingly, substantially the same urging force can be applied to the barrier blades 202 to 205 in the open position and the closed position only by assembling without performing adjustment work, and the barrier mechanism that realizes the above invention can be easily achieved. Can be manufactured.

  Further, according to this embodiment, when a driving force equal to or greater than the urging force of the tension spring 413 is applied to the barrier opening / closing ring 408, the barrier blade can be rotated to the closed position side. Accordingly, the barrier blades 202 to 205 are not inadvertently rotated to the closed position side, and the barrier blades 202 to 205 can be reliably positioned at the closed position. In addition, this makes it possible to reliably block external light from entering the optical path.

  The barrier opening / closing ring 408 may be urged toward the closed position, and may be rotated to the open position when a driving force is applied. In this case, the barrier blades 202 to 205 can be rotated toward the open position when a driving force equal to or greater than the urging force of the torsion spring 412 is applied to the barrier opening / closing ring 408. Accordingly, the barrier blades 202 to 205 are not inadvertently rotated to the open position side, and the barrier blades 202 to 205 can be reliably positioned at the closed position only when necessary.

  Further, according to this embodiment, the lens device 100 provided with the barrier mechanism 120, the imaging device provided with the lens device 100, or the imaging device provided with the barrier mechanism 120 can be driven by the lens device 100 or the imaging device. The force can be reduced, and the power consumption of the lens device 100 or the imaging device can be reduced.

  In the above-described embodiment, the urging member is realized by one torsion spring 412. However, the present invention is not limited to this. The urging member may be realized by a plurality of members such as two or more connected springs. Further, the urging member may be realized by a plurality of springs arranged at a plurality of locations.

  In this embodiment, both ends 412a and 412b of the torsion spring 412 are opposed to each other with the bosses 404 and 411 in between, and the boss 411 is brought into contact with the inside of the opposed both ends 412a and 412b. When a driving force that widens the distance between both ends 412a and 412b is transmitted, a biasing force corresponding to the transmitted driving force is applied to the boss 404. However, the present invention is not limited to this.

  For example, when the bosses 404 and 411 are provided on the outer sides of the opposite end portions 412a and 412b, respectively, and the driving force is transmitted by the boss 411 so as to reduce the distance between the both end portions 412a and 412b, the transmitted driving force is transmitted. A biasing force according to the above may be applied to the boss 404.

  As described above, according to the present embodiment, it is possible to reduce the driving force required to drive the barrier mechanism 120, thereby reducing power consumption in the barrier mechanism 120, the lens device 100, and the imaging device. be able to.

  As described above, the barrier mechanism, the lens device, and the imaging device according to the present invention are useful for protecting the objective lens from external impacts, contamination, and the like by covering the objective lens of the camera at the time of non-imaging. Especially, it is suitable when the barrier mechanism is opened and closed using the biasing member.

It is sectional drawing which shows schematic structure of the lens apparatus of embodiment concerning this invention. It is a perspective view (the 1) which shows the barrier mechanism of embodiment concerning this invention. It is a perspective view (the 2) which shows the barrier mechanism of embodiment concerning this invention. It is a disassembled perspective view (the 1) which shows the barrier mechanism of embodiment concerning this invention. It is a disassembled perspective view (the 2) which shows the barrier mechanism of embodiment concerning this invention. It is explanatory drawing (the 1) which shows the opening / closing operation | movement of a barrier mechanism. It is explanatory drawing (the 2) which shows the opening / closing operation | movement of a barrier mechanism. It is explanatory drawing (the 3) which shows the opening / closing operation | movement of a barrier mechanism. It is explanatory drawing (the 4) which shows the opening / closing operation | movement of a barrier mechanism. It is explanatory drawing (the 1) which shows the positional relationship of a rotating shaft, a boss | hub, and a boss | hub. It is explanatory drawing (the 2) which shows the positional relationship of a rotating shaft, a boss | hub, and a boss | hub.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Lens apparatus 120 Barrier mechanism 201 Barrier base 202-205 Barrier blade 401 Rotating shaft 404 Boss 408 Barrier opening / closing ring 411 Boss 412 Torsion spring 413 Tension spring

Claims (8)

A barrier blade provided to be displaceable between an open position where external light is incident on the optical path and a closed position where the external light is blocked from entering the optical path;
The biasing member has a biasing member, and the driving force from the driving source is transmitted to the barrier blade through the biasing member, so that the barrier blade is moved from the open position to the closed position side and from the closed position to the open position side. A drive mechanism that is displaced to
With
The urging member urges the barrier blade in the open position toward the open position and urges the barrier blade in the closed position toward the closed position. A barrier blade provided to be displaceable between an open position where external light is incident on the optical path and a closed position where the external light is blocked from entering the optical path;
The biasing member has a biasing member, and the driving force from the driving source is transmitted to the barrier blade through the biasing member, so that the barrier blade is moved from the open position to the closed position side and from the closed position to the open position side. A drive mechanism that is displaced to
With
The urging member urges the barrier blade toward the closed position when the barrier blade is displaced toward the closed position, and opens the barrier blade when the barrier blade is displaced toward the open position. A barrier mechanism characterized by being provided so as to be biased to the side.   The barrier mechanism according to claim 1, wherein the urging member causes substantially the same urging force to act on the barrier blades at the closed position and the open position.   The biasing member switches the biasing direction to the closed position in the middle of displacement of the barrier blade from the open position to the closed position, and biases in the middle of displacement from the closed position to the open position. The barrier mechanism according to any one of claims 1 to 3, wherein the barrier mechanism is provided so as to be switched to the open position side. The drive mechanism is
A rotating shaft to which the barrier blade is rotatably connected;
A first boss that is provided so as to be capable of reciprocating in the vicinity of the rotation shaft and reciprocates to generate the urging force on the urging member;
A second boss that is provided on the barrier blade and receives a biasing force from the biasing member when the biasing member comes into contact with the reciprocating motion of the first boss;
A torsion spring as the biasing member wound around the rotating shaft and extending so that both end portions face each other with the first boss and the second boss in between,
The torsion spring causes the other end side to abut on the second boss when the first boss abuts on one end side as the first boss moves forward, and the first boss When the first boss comes into contact with the other end portion as the valve moves backward, the driving force from the drive source is applied to the barrier blade by bringing the one end portion into contact with the second boss. It transmits, The barrier mechanism as described in any one of Claims 1-4 characterized by the above-mentioned.   An angle formed by a straight line passing through the pivot shaft and the second boss at the open position and a straight line passing through the pivot shaft and the first boss at the closed position is equal at the open position and the closed position. The barrier mechanism according to claim 5, wherein the barrier mechanism is provided as follows.   A lens device comprising the barrier mechanism according to any one of claims 1 to 6 and an optical member that forms an optical path through which external light is incident on the image sensor.   An image pickup apparatus comprising the image pickup element and the lens device according to claim 7.

Images