JP2010277026A - Lens barrier device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens barrier device which suppresses collision noise generated when barrier blades are closed. <P>SOLUTION: A first barrier blade 4 is biased so as to be closed by a first biasing member 3. Using an opening/closing locking mechanism constituted between the first barrier blade 4 and a barrier drive member 2 mounted on the opening of a lens front surface so as to be rotatable, the first barrier blade 4 is configured so as to be opened along with the rotating of the barrier drive member 2. The second barrier blade 5 is disposed adjacent to the direction of the optical axis of the first barrier blade 4. An inside end side portion along the outer shape of a third barrier blade 7 is disposed so as to be in slide contact with an outside end side portion along the outer shape of the second barrier blade 5. The third barrier blade 7 is biased so as to be closed by a second biasing member 6. Thereby, the second biasing member 6 indirectly energizes the second barrier blade 5 so that the blade 5 is closed. Using a cam mechanism for opening/closing control constituted between the second biasing member 6 and barrier drive member 2, the second biasing member 6 and the third barrier blade 7 are opened along with the rotation of the barrier drive member 2. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a lens barrier device mounted to protect a lens of a digital camera, a silver salt camera, a video camera, or the like.

  In general, there are mainly two types of lens barrier devices that are mounted to protect a lens such as a camera. The first method is to cover the whole or part of the lens barrel by closing a cover attached to the camera body. The second is a lens-barrier system in which the lens barrier mechanism is built in the retracting lens barrel, the barrier blades are retracted to a place other than the lens opening of the lens barrel when used, and the blades close when retracted. .

  Further, in the conventional lens barrier device, one first and second barrier blades and the other first and second barrier blades are respectively attached around a common axis so that the open position and the closed position are It is configured to perform a moving operation related to each other. Then, the first and second barrier blades axially mounted on one axis overlap each other and are stored in the open position, and the first and second barrier blades axially mounted on the other axis are mutually connected. It is configured to overlap and be stored in the open position. Furthermore, an in-cylinder lens barrier mechanism that suppresses an increase in the dimension in the optical axis direction due to an increase in the number of barrier blades has been proposed by overlapping three barrier blades in the order of metal, mold resin, and metal. (For example, refer to Patent Document 1).

JP 2007-102086 A

  In such a lens barrier device, the first barrier blade and the second barrier blade that are coaxially mounted are operated by biasing forces of biasing members different from each other. In such a lens barrier device, the second barrier blade is automatically closed by using the movement of the second barrier blade as part of the closing operation of the first barrier blade. It is conceivable to configure. In such a configuration, when the second barrier blade indirectly urged by the urging member closes during the operation from the open state to the closed state, the two barrier blades collide with each other, and the collision sound is generated. It sometimes occurred. However, in such a lens barrier device, the second barrier blade operates by a mechanism that is indirectly urged by the urging member. Therefore, the urging force of the urging member is controlled to generate a collision sound. It is difficult to suppress.

  An object of the present invention is to provide a lens barrier device capable of suppressing a collision sound generated when a barrier blade is fully closed.

  In order to achieve the above object, the lens barrier device according to claim 1 includes a first barrier blade, a second barrier blade, and a third barrier blade for closing the opening on the front surface of the lens in an openable and closable manner. In the lens barrier device, the first barrier blade is urged so as to be closed by a first urging member, and the first barrier blade and a barrier drive rotatably attached to the opening of the front surface of the lens The first barrier blade is configured to open by interlocking with the rotation operation of the barrier driving member by an opening / closing operation locking mechanism formed between the member and the optical axis of the first barrier blade. The second barrier blade is disposed adjacent to the direction, and the inner edge portion along the outer shape of the third barrier blade slides on the outer edge portion along the outer shape of the second barrier blade. The third burr is arranged so as to contact By urging the blade to be closed by the second urging member, the second urging member urges the second barrier blade to be closed indirectly, and the second urging member And the opening / closing control cam mechanism formed between the barrier driving member and the barrier driving member, the second urging member and the third barrier blade are opened in conjunction with the rotation of the barrier driving member. It is characterized by being configured.

  According to the present invention, by controlling the behavior of the barrier blades during the closing operation, there is an effect that it is possible to provide a lens barrier device that suppresses the collision sound generated when the barrier blades are fully closed.

It is a disassembled perspective view of the lens barrier apparatus which protects lenses, such as a camera, concerning embodiment of this invention. It is a front view which shows the open state of the barrier blade | wing of the 1st group barrel which removed the cap and barrier cover which protect the lens barrier apparatus concerning this Embodiment. It is a front view which shows the closed state of the barrier blade | wing of the 1st group lens barrel which removed the cap and barrier cover which protect the lens barrier apparatus concerning this Embodiment. It is explanatory drawing which shows the track | orbit accompanying the opening / closing operation | movement of the cam groove installed in the drive member in the lens barrier apparatus concerning this Embodiment, and the pin combined with it.

  Hereinafter, a lens barrier device mounted to protect a lens of a camera according to an embodiment of the present invention will be described with reference to FIGS.

  The lens barrier device according to the present embodiment is configured to be usable as an in-lens lens barrier device provided in a retractable lens barrel of an imaging device.

  In FIG. 1, 1 is a first group cylinder, 2 is a barrier drive ring (barrier drive member), 3 is a coil spring, 4 is a pair of barrier inner blades, 5 is a pair of barrier outer blades, 6 is a torsion spring, and 7 is a pair. Barrier blades 8 are barrier covers.

  In this lens barrier device, a barrier drive ring 2 is mounted on the subject side of the first lens barrel 1 so as to be rotatable by a predetermined angle. Further, a pair of barrier inner blades 4, a pair of barrier outer blades 5, a pair of barrier small blades 7, a barrier cover 8, and a cover member 9 are sequentially arranged on the subject side of the barrier drive ring 2.

  The first group cylinder 1 is a lens barrel member for holding a lens unit arranged closest to the subject in the photographing optical system housed in the lens barrel.

  A barrier drive ring 2 is mounted on the subject side (object side or front side) end of the first lens barrel 1 in the optical axis direction by a bayonet structure. In other words, the barrier drive ring 2 has a first mirror with a bayonet structure in which flange portions protruding radially outward from four locations in the circumferential direction are engaged with bayonet claws provided at four locations of the first lens barrel 1. It is attached to the cylinder 1.

  At the same time, the barrier drive ring 2 is attached to the first barrel 1 so as to be rotatable within a predetermined angle around the optical axis. For this reason, although not shown, the barrier drive ring 2 has projections formed at four locations in the circumferential direction inserted into the arc groove formed in the first lens barrel 1 so that the inner side on the radially outer side of the arc groove is formed. It is mounted by contacting (diameter fitting) with the peripheral surface.

  In the barrier drive ring 2, a substantially rectangular opening 21 corresponding to the substantially rectangular cover opening 81 formed in the barrier cover 8 is formed.

  The opening 21 of the barrier drive ring 2 and the cover opening 81 of the barrier cover 8 are substantially rectangular having a size corresponding to an effective opening area (an area where a light beam effective for imaging is incident) on the front surface of the lens unit. Form in the opening. As a result, the barrier driving ring 2 is formed with a light shielding portion 22 that is an arc-shaped flat plate surface on the radially outer side of the opening 21.

  Between the opening 21 of the barrier drive ring 2 and the cover opening 81 of the barrier cover 8, a pair of barrier inner blades 4 and a pair of barrier outer blades for closing and protecting the opening on the front surface of the lens in the closed state. 5 and a pair of barrier blades 7 are arranged.

  On the subject side of the barrier drive ring 2, a pair of barrier inner blades 4 that are first barrier blades are arranged. The pair of barrier inner blades 4 are pivotally attached to the bearing portion of the first lens barrel 1 with the shaft portions provided at the respective base end portions so that the open position shown in FIG. 2 and the closed position shown in FIG. It is attached so that it can be opened and closed by rotating between them.

  The pair of barrier inner blades 4 serving as the first barrier blades are configured to be opened and closed in conjunction with the rotation operation of the barrier drive ring 2.

  For this reason, an arm portion extending from the shaft portion is provided at the base end portion of the pair of barrier inner blades 4, and a coil spring 3 (first coil spring) (first coil spring) is provided between the arm portion and the first lens barrel 1. 1 urging member) is installed. Each of the pair of barrier inner blades 4 is urged so as to be closed by a coil spring 3 (first urging member).

  In this lens barrier device, in order to open the pair of barrier inner blades 4 in conjunction with the rotation operation of the barrier driving ring 2, an opening / closing operation locking mechanism is provided between the barrier driving ring 2 and the barrier inner blade 4. Provide. In order to configure this opening / closing operation locking mechanism, locking protrusions (not shown) are provided at the distal ends of the arm portions provided at the base end portions of the pair of barrier inner blades 4. Further, in order to constitute this opening / closing operation locking mechanism, an operation protrusion (not shown) is provided at a predetermined position of the barrier drive ring 2 so as to be able to contact the locking protrusions of each barrier inner blade 4. In this lens barrier device, the operation protrusion of the barrier drive ring 2 that has been rotated hits the locking protrusion of each barrier inner blade 4, and resists the biasing force of the coil spring 3 to form a pair of barrier inner blades 4. The opening / closing operation locking mechanism is configured so as to open.

  A pair of barrier outer blades 5 as a second barrier blade and a pair of barrier small blades 7 as a third barrier blade are arranged on the subject side of the pair of barrier inner blades 4 configured as described above.

  The pair of barrier outer blades 5 are axially attached to the shaft portions of the base end portions of the corresponding pair of barrier inner blades 4 so as to be coaxial with the shaft portions of the corresponding pair of barrier inner blades 4, and are opened as shown in FIG. 3 and the closed position shown in FIG.

  Thereby, when a pair of barrier outer blade | wing 5 which is a 2nd barrier blade | wing will be in a closed state, it will be in the state which a pair of barrier inner blade | wing 4 and side plane which correspond respectively overlap adjacently.

  As shown in FIGS. 1 to 3, each of the barrier outer blades 5, which are the second barrier blades, has a corresponding third barrier blade at a position adjacent to the edge portion along the outer shape on the free end side. A certain barrier small blade 7 is arranged. That is, it arrange | positions so that the inner side edge part along the external shape of the barrier small blade 7 may slidably contact with the outer side edge part along the external shape of the barrier outer blade | wing 5. FIG.

  The pair of barrier small blades 7 as the third barrier blades are arranged with their respective base end portions pivotally attached to predetermined positions of the first group cylinder 1. Further, the pair of barrier outer blades 5 and the pair of barrier small blades 7 are configured to perform an opening / closing operation in the same plane.

  Further, a torsion spring 6 as a second urging member is installed between the base end portion of each barrier small blade 7 and the first group cylinder 1 so that each barrier small blade 7 is always attached in the closing direction. It is configured to be supported.

  Further, on the outer peripheral portion on the free end side of each barrier outer blade 5, the inner peripheral portion on the free end side of the corresponding barrier small blade 7 is caused by the biasing force of the torsion spring 6 that is the second biasing member. It is configured to be pressed.

  Thereby, each outer barrier blade 5 is configured to be always urged in the closing direction by the urging force of the torsion spring 6 acting via the corresponding barrier wing 7.

  For this reason, the pair of barrier small blades 7 perform an opening / closing operation in conjunction with the pair of barrier outer blades 5. That is, the pair of barrier small blades 7 are configured to follow the corresponding barrier outer blades 5 when closed, and to be pushed open to the corresponding barrier outer blades 5 when opened.

  The lens barrier device also includes an open / close control cam mechanism (open / close control mechanism) that controls the open / close operation of the barrier outer blade 5 that does not have a member to be directly urged by the operation of the barrier drive ring 2. .

  The cam mechanism for opening / closing control as a mechanism for controlling the behavior of the barrier blades includes a cam groove 2a for opening / closing operation provided in the barrier drive ring 2 and a follower as a follower protruding from each barrier outer blade 5. And a pin 5a.

  As shown in FIGS. 1 to 3, the opening / closing cam groove 2 a is provided at a predetermined position of the light shielding portion 22 of the barrier drive ring 2. The opening / closing cam groove 2 a is formed by projecting a deformed U-shaped rib on the plane of the light shielding portion 22.

  The cam groove 2a for opening / closing operation includes a first cam side 200 and a second cam side 201 formed in a smooth curve that forms a part of a spiral line from the rotation center to the outer periphery of the barrier drive ring 2. It is configured to be arranged substantially in parallel with a predetermined interval. Furthermore, the cam groove 2a for opening / closing operation is formed in a shape in which the center side end portions of the first cam side 200 and the second cam side 201 are connected by the bottom side portion. An extension guide end 202 extending in the circumferential direction of the barrier drive ring 2 is formed at the free end of the first cam side 200.

  The open / close control cam mechanism is configured by loosely inserting the corresponding driven pins 5a of the corresponding barrier outer blades 5 in the deformed U-shaped spaces surrounded by the open / close operation cam grooves 2a thus configured. To do.

  Next, an opening / closing operation in the lens barrier device configured as described above will be described.

  In this lens barrier device, in the opened state shown in FIG. 2, the barrier drive ring 2 is rotationally driven to the open position, whereby the operation protrusion (not shown) of the barrier drive ring 2 becomes the locking protrusion of the barrier inner blade 4. A pair of barrier inner blades 4 are held in contact with each other (not shown). In this open state, the urging force of the coil spring 3 (first urging member) acts on the operation protrusion of the barrier drive ring 2 from the locking protrusion of the barrier inner blade 4, so that the barrier drive ring 2 is restrained. By this, it is comprised so that an open state may be maintained.

  Further, in this lens barrier device, in the open state shown in FIG. 2, the extension guide end portion 202 of the opening / closing operation cam groove 2a in the barrier drive ring 2 makes contact with the driven pin 5a, thereby causing the pair of barrier outer blades 5 to move. Keeping it open.

  In this open state, the urging force of the torsion spring 6 that is the second urging member acts in a direction to close the barrier outer blade 5 by rotating the barrier outer blade 5 around the shaft-attached portion through the barrier small blade 7. Yes. For this reason, the direction in which the driven pin 5 a of the barrier outer blade 5 is in pressure contact with the extension guide end 202 is substantially directed toward the center of rotation of the barrier drive ring 2. Here, since the extension guide end 202 is formed along the circumferential direction of the barrier drive ring 2, the force exerted on the extension guide end 202 by the driven pin 5 a of the barrier outer blade 5 is the extension guide end. The direction is orthogonal to the portion 202. Therefore, in this open state, the urging force that the torsion spring 6 applies to the barrier drive ring 2 via the barrier small blade 7 and the barrier outer blade 5 does not work in the direction in which the barrier drive ring 2 is rotated. It is possible to reduce the force for maintaining the in an open state.

  Next, the case where the open state shown in FIG. 2 is shifted to the closed state shown in FIG. 3 will be described. When shifting to this closed state, the barrier drive ring 2 is rotationally driven in the direction of arrow A in FIG. Then, the driven pin 5a of the barrier outer blade 5 that receives the urging force of the torsion spring 6 is guided and moved from the extended guide end portion 202 of the opening / closing operation cam groove 2a to the first cam side 200 side. That is, the driven pin 5a of the outer barrier blade 5 is guided by the extension guide end portion 202 and the first cam side 200, and is driven following the path shown in FIG. Following the operation of the driven pin 5a, the barrier outer blades 5 and the barrier small blades 7 rotate about their respective shaft-attached portions and shift to the closed state shown in FIG.

  The movement to the closed state is performed while the driven pin 5 a of the barrier outer blade 5 slides on the first cam side 200, so that the urging force of the torsion spring 6 is received by the first cam side 200. It will be. Therefore, the barrier outer blade 5 that indirectly receives the biasing force of the torsion spring 6 is closed while slowly rotating in synchronization with the rotation operation of the barrier drive ring 2. For this reason, in this lens barrier apparatus, it can suppress that a pair of barrier outer blade | wings 5 collide and generate | occur | produce a collision sound at the time of closing operation.

  In the operation for shifting to the closed state, after the pair of barrier outer blades 5 are in the closed state, the barrier drive ring 2 is further rotated to the state shown in FIG. In the state of FIG. 3, the driven pin 5 a is in a state of being loosely placed in the deformed U-shaped inner middle of the opening / closing operation cam groove 2 a, and thus the pair of barrier outer blades 5 are indirectly connected to the torsion spring 6. The closed state is maintained by the urging force. Further, in this closed state, the driven pin 5a is in a state of being loosely placed in the deformed U-shaped inner middle of the opening / closing operation cam groove 2a, and the driven pin 5a is restrained by the second cam side 201. Sufficient escape space is secured. Therefore, when an external force is applied to push open the barrier outer blade 5, the pair of barrier outer blades 5 are slightly opened to avoid applying excessive external force to the barrier outer blade 5 and the barrier small blade 7. be able to.

  Further, in the operation of moving the pair of barrier inner blades 4 to the closed state, the operation protrusion of the barrier drive ring 2 comes into contact with the locking protrusion of the barrier inner blade 4 and the coil spring 3 (first urging member) is moved. I am receiving an energizing force. For this reason, the opening operation of the pair of barrier inner blades 4 is slowly closed following the rotation operation of the barrier drive ring 2. Therefore, in this lens barrier apparatus, it can suppress that a pair of barrier inner blade | wings 4 collide and generate | occur | produce a collision sound at the time of closing operation.

  As described above, in this lens barrier device, the opening / closing operation of the barrier outer blade 5 that does not have a member to be directly biased is controlled by the operation of the barrier driving ring 2 by the cam mechanism including the cam groove 2a and the pin 5a. It is configured to be able to. That is, this lens barrier device is configured to suppress the generation of sound due to a collision by controlling the opening / closing operation of the barrier outer blade 5 that does not have a member to be urged directly by the operation of the barrier drive ring 2. Has been.

  Therefore, in this lens barrier device, the opening / closing operation of the barrier outer blade 5 is controlled by the operation of the barrier drive ring 2, thereby suppressing the occurrence of sound due to collision when the pair of barrier outer blades 5 are closed. can do.

  In addition, this invention is not limited to embodiment mentioned above, Of course, in the range which does not deviate from the summary of this invention, a various structure can be taken.

  For example, in the above-described embodiment, the barrier mechanism used for the digital camera has been described. However, the present invention is not limited to this, and may be applied to a barrier mechanism used in an apparatus including a silver salt camera, a video camera, a portable device with a camera function, and other optical devices and optical devices.

1 Group cylinder 2 Drive ring 2a Cam groove 3 Coil spring 4 Barrier inner blade 5 Barrier outer blade 5a Pin 6 Torsion spring 7 Barrier small blade

Claims (2)

In the lens barrier device including the first barrier blade, the second barrier blade, and the third barrier blade for closing the opening on the front surface of the lens in an openable / closable manner,
Urging the first barrier blade to close with a first urging member;
The opening / closing locking mechanism configured between the first barrier blade and the barrier driving member rotatably attached to the opening on the front surface of the lens interlocks with the rotation operation of the barrier driving member. Configured to open the first barrier blade,
The second barrier blade is disposed adjacent to the optical axis direction of the first barrier blade,
Arranged so that the inner edge portion along the outer shape of the third barrier blade is in sliding contact with the outer edge portion along the outer shape of the second barrier blade,
By urging the third barrier blade to be closed by the second urging member, the second urging member is urged to indirectly close the second barrier blade,
The opening / closing control cam mechanism formed between the second urging member and the barrier driving member is interlocked with the rotation operation of the barrier driving member, and the second urging member and the third driving member. The lens barrier device is configured to open the barrier blades. The opening / closing control cam mechanism is:
An opening / closing operation cam groove formed in the light shielding portion of the barrier driving member;
A driven pin projecting from the second urging member so as to be loosely inserted into the opening / closing operation cam groove;
When the barrier driving member is rotationally driven, the driven pin is driven along the opening / closing operation cam groove to open the second urging member. The lens barrier device according to claim 1.