JP2008292869A - Lens barrel, camera and personal digital assistant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a lens barrel having a retracting lens which retracts from an optical axis when it is collapsed and housed, and capable of surely inserting the retracting lens in the optical axis by effectively preventing an operation mechanism for inserting the retracting lens from being stopped in the middle of actuation. <P>SOLUTION: A retracting lens moving frame 32 is provided with a retracting lens operation mechanism which inserts/separates a retracting lens group 3 in/from the optical axis through a retracting lens holding frame 31 and moves the retracting lens group 3 on the optical axis. The retracting lens operation mechanism is provided with a cam surface 32a for ordinary operation to perform ordinary inserting/separating operation of the retracting lens in/from the optical axis, and a cam surface 32c for forcible insertion to forcibly move the retracting lens along the optical axis in the retracting lens moving frame 32. Furthermore, the retracting lens operation mechanism has a cam follower for driving 35a engaged with the cam surface 32a for ordinary operation and the cam surface 32c for forcible insertion on a female screw member 35 driven by a lead screw 38. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention has a so-called collapsible configuration in which the lens group is retracted and stored in one form, and the lens group is extended to a predetermined position and used in the other form, and the lens is retracted when the lens barrel is retracted. This is related to a lens barrel that retracts a part of the group from the optical axis, especially when the retracted lens is inserted on the optical axis and the insertion operation is hindered due to interference with other members or friction. In addition, the present invention relates to a lens barrel, a camera, and a portable information terminal device that are surely inserted on the optical axis.

In an imaging apparatus typified by a camera such as a digital camera, a lens mirror other than the time of shooting has been developed along with the progress of high performance of a shooting lens such as a zoom lens capable of changing a focal length and downsizing according to user requirements. There is an increasing use of a so-called collapsible type taking lens in which a cylinder is housed in an image pickup apparatus main body. Furthermore, it is important not only to reduce the size but also to reduce the thickness of the lens barrel portion in the retracted state to the limit due to the demand for further thinning.
As a technique for coping with such a request for thinning of the image pickup apparatus, there is a retractable structure in which the lens barrel is housed in the image pickup apparatus main body other than at the time of photographing, and some lenses are provided when the lens barrel is retracted. An imaging apparatus using a lens barrel having a configuration for retracting the lens from the optical axis is already known. The configuration of such a lens barrel is disclosed in, for example, Patent Document 1 (Japanese Patent No. 3771932), Patent Document 2 (Japanese Patent Laid-Open No. 2006-337695), Patent Document 3 (Japanese Patent Laid-Open No. 2006-58455), and Patent Document 4 (Japanese Patent Laid-Open No. 2006-58455). No. 2006-243605). According to these lens barrels disclosed in Patent Document 1 to Patent Document 3, when the lens barrel is housed, a part of the lens is retracted from the optical axis, so that the size of the entire lens in the optical axis direction is reduced. And the thickness of the imaging device can be reduced.

That is, in any of Patent Document 1 (Japanese Patent No. 377932), Patent Document 2 (Japanese Patent Laid-Open No. 2006-337695), Patent Document 3 (Japanese Patent Laid-Open No. 2006-58455), and Patent Document 4 (Japanese Patent Laid-Open No. 2006-243605) However, the retractable lens that retracts from the optical axis when retracted is urged by a spring to be placed on the optical axis during shooting, and retracts outward from the optical axis against the spring when retracted. It is disclosed.
As in these Patent Documents 1 to 4, the lens barrel has a collapsible configuration in which the lens barrel is accommodated in the image pickup apparatus body other than during photographing, and some lenses are on the optical axis when the lens barrel is retracted. In an imaging apparatus having a lens barrel configured to be retracted from the lens, in general, in order to insert the retractable lens on the optical axis, the insertion operation is achieved using the force of a spring. If the retractable lens cannot be inserted due to this trouble, the lens system will not be established.
For example, in Patent Document 4 (Japanese Patent Application Laid-Open No. 2006-243605), the lens holding frame is used for photographing in order to further reduce the size of the movable barrel in the photographing optical axis direction without increasing the outer diameter of the movable barrel. In the state, all the lens groups are positioned on the photographing optical axis, and in the retracted state, the two lens groups of the third lens group and the fourth lens group are located at positions different from the photographing optical axis and movable mirrors of the other lens groups. A configuration including a retractable lens holding frame (31, 41) that holds and moves two lens groups (13, 14) in order to retract outside the maximum outer diameter of the tube (22) is disclosed.

Such a rotation operation mechanism for inserting a retractable lens such as the third lens holding frame or the fourth lens holding frame shown in Patent Document 4 (more specifically, for example, implementation of the present application described later) (Refer to the retractable lens moving frame 32 in this form), when it comes into contact with other adjacent parts, it cannot be rotated only by the force of the spring, and the rotation operation mechanism may stop in the middle of rotation. In such a case, a predetermined lens system is not established, and an appropriate optical function cannot be achieved.
In addition, if an imaging device such as a camera is to be thinned for compactness or the like, a fixing space on the side for fixing a biasing member such as a spring for biasing a rotation mechanism (such as a retracting lens moving frame) is fixed. There was also a problem that it was difficult to secure.

Japanese Patent No. 3771932 JP 2006-337695 A JP 2006-58455 A JP 2006-243605 A

The present invention has been made in view of the above-described circumstances, and in a lens barrel having a retractable lens that retracts from the optical axis when retracted, an operating mechanism (or an operating mechanism; the same applies hereinafter) for inserting the retractable lens. The purpose of the present invention is to provide a lens barrel, a camera, and a portable information terminal device that effectively prevent the lens from being stopped during operation and enable the retractable lens to be reliably inserted onto the optical axis. Yes.
The object of the first aspect of the present invention is to forcibly operate the operating mechanism for inserting the retractable lens even when it is stopped during the operation, so that the retractable lens is reliably inserted on the optical axis. It is an object of the present invention to provide a lens barrel that makes it possible.
An object of claim 2 of the present invention is to provide a lens barrel capable of reliably inserting a retractable lens on the optical axis, particularly with a configuration that can operate more reliably.
A third object of the present invention is to provide a lens barrel that can occupy a small space and can insert a retractable lens on the optical axis with a simpler structure.
A fourth object of the present invention is to provide a lens barrel that allows a retractable lens to be smoothly and reliably inserted onto the optical axis with a simpler structure.
The object of claim 5 of the present invention is to enable the optical system to be appropriately established by forcibly operating, particularly when the insertion operation of the retractable lens is hindered and the operation mechanism stops during operation. To provide a lens barrel.

An object of claim 6 of the present invention is to provide a lens barrel that can insert a retractable lens on an optical axis with a simple and less occupied space that can operate more reliably. It is in.
The object of claim 7 of the present invention is to make the operating mechanism for inserting the retractable lens smoothly operate, and as long as it is operating normally, there is no risk of hindering the operation, and the retractable lens can be reliably An object of the present invention is to provide a lens barrel that can be inserted on the optical axis.
The object of the present invention is to make it possible to retract an appropriate retractable lens from the optical axis particularly when retracted, and to reliably insert the retractable lens onto the optical axis when in use. The object is to provide a lens barrel.
The object of claim 9 of the present invention is to enable the retractable lens to be more appropriately retracted from the optical axis when retracted, and to securely insert the retractable lens onto the optical axis during use. It is to provide a lens barrel.
An object of claim 10 of the present invention is to provide a lens barrel capable of reliably and more accurately inserting a retractable lens on an optical axis even when constructed with relatively low dimensional accuracy. is there.

An object of an eleventh aspect of the present invention is to provide a lens barrel that allows a retractable lens to be surely inserted on the optical axis with a compact configuration that can be made thinner.
The object of the present invention is to forcibly operate the operating lens for inserting the retractable lens in the lens barrel even when the operating mechanism stops in the middle of the operation, so that the retractable lens can be securely connected to the optical axis. The object is to provide a camera that can be inserted above.
The object of the thirteenth aspect of the present invention is to ensure that the retractable lens can be reliably operated by forcibly operating it even when the operation mechanism for inserting the retractable lens in the lens barrel stops during operation. An object of the present invention is to provide a portable information terminal device that can be inserted above.

In order to achieve the above-described object, a lens barrel according to the present invention described in claim 1 is provided.
In a lens barrel that is in a photographing state by moving at least a part of the plurality of lens groups to the object side from a retracted state in which at least a part of the plurality of lens groups is retracted to store the lens group,
A plurality of lens holding frames for holding the plurality of lens groups for each lens group;
A movable lens barrel holding the lens holding frame inside;
Lens holding frame driving means for driving the lens holding frame via the movable lens barrel;
The lens holding frame is
In the photographing state, all the lens groups are positioned on the same optical axis, and in the retracted state, the at least one lens group is held so that at least one lens group is retracted outside the inner diameter of the movable lens barrel. A retractable lens holding frame;
A lens barrel including a retractable lens moving frame for holding and moving the retractable lens holding frame,
The retractable lens moving frame is configured such that the at least one lens group is inserted into and removed from the optical axis via the retractable lens holding frame, and the at least one lens group is moved on the optical axis. Provided,
The retracting lens operating mechanism is
A normal operation cam for normal insertion / removal operation with respect to the optical axis;
A forced insertion cam for forcibly moving toward the optical axis;
A drive cam follower that engages with these cams is included.

A lens barrel according to the present invention described in claim 2 is the lens barrel of claim 1,
The normal operation cam and the forced insertion cam are formed as separate bodies.
A lens barrel according to a third aspect of the present invention is the lens barrel according to the first aspect,
The normal operation cam and the forced insertion cam are formed integrally on the same member.
The lens barrel according to the present invention described in claim 4 is the lens barrel according to claim 1 or 3,
The normal operation cam and the forced insertion cam are formed integrally with the retractable lens moving frame.
The lens barrel according to the present invention described in claim 5 is the lens barrel according to any one of claims 1 to 4,
The forcible insertion cam is a cam for forcible insertion when the at least one lens group is inserted on the optical axis and the insertion operation is hindered due to some trouble. Yes.

A lens barrel according to a sixth aspect of the present invention is the lens barrel according to any one of the first to fifth aspects,
The forced insertion cam has a shape substantially similar to that of the normal operation cam.
A lens barrel according to a seventh aspect of the present invention is the lens barrel according to any one of the first to sixth aspects,
The forcibly inserting cam is not in contact with the cam follower when the retracting lens moving frame is in the retracted state.
A lens barrel according to the present invention described in claim 8 is the lens barrel according to any one of claims 1 to 7,
The lens group held by the retractable lens holding frame is at least one of a lens group having the smallest lens diameter among the plurality of lens groups and a lens group having the lowest decentering sensitivity among the plurality of lens groups. It is characterized by.
A lens barrel according to a ninth aspect of the present invention is the lens barrel according to any one of the first to eighth aspects,
Between the lens groups contributing to zooming in the plurality of lens groups, there is provided at least one stop having a variable aperture diameter, and the lens group held by the retractable lens holding frame is more image plane than the stop. It is a lens group on the side.

A lens barrel according to a tenth aspect of the present invention is the lens barrel according to any one of the first to ninth aspects,
The retractable lens holding frame and the retractable lens moving frame are configured such that the retractable lens holding frame can be fixed by being relatively decentered on a surface where the optical axes perpendicularly intersect the retractable lens moving frame. It is characterized by.
The lens barrel according to the present invention described in claim 11 is the lens barrel according to claim 3 or 4,
The retracting lens moving frame has a concave portion for attaching an urging member for generating an operation force for an insertion operation on the optical axis by the normal operation cam. It is characterized by being formed so as to avoid the position of the cam for normal operation.

A camera according to the present invention described in claim 12 is provided.
The imaging optical system includes the lens barrel according to any one of claims 1 to 11.
According to a thirteenth aspect of the present invention, a portable information terminal device includes:
An imaging optical system of the camera function unit includes the lens barrel according to any one of claims 1 to 11.

According to the present invention, in a lens barrel having a retractable lens that retracts from the optical axis when retracted, the operating mechanism for inserting the retractable lens is effectively prevented from being stopped during operation. It is possible to provide a lens barrel, a camera, and a portable information terminal device that enable a lens to be reliably inserted on the optical axis.
That is, according to the lens barrel of claim 1 of the present invention,
In a lens barrel that is in a photographing state by moving at least a part of the plurality of lens groups to the object side from a retracted state in which at least a part of the plurality of lens groups is retracted to store the lens group,
A plurality of lens holding frames that respectively hold the plurality of lens groups for each lens group; a movable lens barrel that holds the lens holding frame inside;
Lens holding frame driving means for driving the lens holding frame via the movable lens barrel;
The lens holding frame is
In the photographing state, all the lens groups are positioned on the same optical axis, and in the retracted state, the at least one lens group is held so that at least one lens group is retracted outside the inner diameter of the movable lens barrel. A retractable lens holding frame;
A retractable lens moving frame for holding and moving the retractable lens holding frame,
The retractable lens moving frame is configured such that the at least one lens group is inserted into and removed from the optical axis via the retractable lens holding frame, and the at least one lens group is moved on the optical axis. Provided,
The retracting lens operating mechanism is
A cam for normal operation for normal insertion / removal operation with respect to the optical axis, a cam for forced insertion for forcibly moving toward the optical axis,
By including a driving cam follower that engages with these cams,
Even when the operation mechanism for inserting the retractable lens is stopped during operation, the retractable lens can be forcibly operated to reliably insert the retractable lens on the optical axis.

According to the lens barrel of claim 2 of the present invention, in the lens barrel of claim 1,
The cam for normal operation and the cam for forced insertion are formed separately,
In particular, the retractable lens can be reliably inserted on the optical axis with a configuration that can operate more reliably.
According to the lens barrel of claim 3 of the present invention, in the lens barrel of claim 1,
The normal operation cam and the forced insertion cam are integrally formed on the same member,
In particular, the retractable lens can be surely inserted on the optical axis with a simpler configuration in which the distance between the two cams is accurately formed and a small occupied space is sufficient.
According to the lens barrel of claim 4 of the present invention, in the lens barrel of claim 1 or claim 3,
The normal operation cam and the forced insertion cam are formed integrally with the retractable lens moving frame,
In particular, the retractable lens can be smoothly and reliably inserted on the optical axis with a simpler configuration.

According to the lens barrel of claim 5 of the present invention, in the lens barrel of any one of claims 1 to 4,
The forcibly inserting cam is a cam for forcibly inserting when the at least one lens group is inserted on the optical axis and the insertion operation is hindered due to some trouble,
In particular, when the operation of inserting the retractable lens is hindered and the operation mechanism stops in the middle of operation, it is possible to forcibly operate the optical system and establish the optical system appropriately.
According to the lens barrel of claim 6 of the present invention, in the lens barrel of any one of claims 1 to 5,
The forced insertion cam has a shape substantially similar to the normal operation cam,
In particular, the retractable lens can be reliably inserted on the optical axis with a simple and small-occupying configuration that can operate more reliably.

According to the lens barrel of claim 7 of the present invention, in the lens barrel of any one of claims 1 to 6,
The forced insertion cam is not in contact with the cam follower in the retracted state in which the retractable lens moving frame is in the retracted position.
In particular, the operating mechanism for inserting the retractable lens is smoothly operated by the one-sided cam, and as long as the operating mechanism is operating normally, the retractable lens is securely inserted on the optical axis without any risk of hindering the operation. It becomes possible.
According to the lens barrel of claim 8 of the present invention, in the lens barrel of any one of claims 1 to 7,
The lens group held by the retractable lens holding frame is at least one of a lens group having the smallest lens diameter among the plurality of lens groups and a lens group having the lowest decentering sensitivity among the plurality of lens groups. By
In particular, when retracted, the retractable lens can be retracted from the optical axis so that the retractable space is small and the effect on image quality can be minimized. Can be inserted.

According to the lens barrel of claim 9 of the present invention, in the lens barrel of any one of claims 1 to 8,
Between the lens groups contributing to zooming in the plurality of lens groups, there is provided at least one stop having a variable aperture diameter, and the lens group held by the retractable lens holding frame is more image plane than the stop. By being the side lens group,
In particular, when retracted, it is possible to retract a more appropriate retractable lens from the optical axis so that the moving distance of the lens group in the retracted to photographing state is short and a simple mechanism. It can be surely inserted on the optical axis.
According to the lens barrel of claim 10 of the present invention, in the lens barrel of any one of claims 1 to 9,
The retractable lens holding frame and the retractable lens moving frame are configured such that the retractable lens holding frame can be fixed by being relatively decentered on a surface where the optical axes perpendicularly intersect the retractable lens moving frame. By
In particular, the dimensional accuracy can be adjusted, and even with a relatively low dimensional accuracy, the retractable lens can be reliably and more accurately inserted onto the optical axis.

According to the lens barrel of claim 11 of the present invention, in the lens barrel of claim 3 or claim 4,
The retracting lens moving frame has a concave portion for attaching an urging member for generating an operation force for an insertion operation on the optical axis by the normal operation cam. By avoiding the position of the cam for normal operation,
In particular, the retractable lens can be reliably inserted on the optical axis with a compact configuration that can be made thinner.
And according to the camera of claim 12 of the present invention,
By including the lens barrel according to any one of claims 1 to 11 as an imaging optical system,
In particular, even when an operation mechanism for inserting the retractable lens in the lens barrel stops during operation, the retractable lens can be surely inserted on the optical axis by forcibly operating it.
According to the portable information terminal device of claim 13 of the present invention,
By including the lens barrel of any one of claims 1 to 11 as an imaging optical system of a camera function unit,
In particular, even when an operation mechanism for inserting the retractable lens in the lens barrel stops during operation, the retractable lens can be surely inserted on the optical axis by forcibly operating it.

Hereinafter, based on an embodiment of the present invention, a lens barrel of the present invention will be described in detail with reference to the drawings.
FIGS. 1-9 has shown the structure of the principal part of 1st Embodiment of the lens barrel which concerns on this invention. FIG. 1 is a perspective view showing an appearance of a lens barrel in a state where the lens group is retracted and housed on the fixed frame side, and FIG. 2 shows an appearance in a state where the lens group is projected from the fixed frame to enable photographing. It is a perspective view. 3 and 4 show the main part of the internal structure of the lens barrel, and FIG. 3 shows the retracting mode of the retracting lens group configured to retract from the optical axis among the plurality of lens groups. FIG. 4 is a perspective view showing a state in which the retractable lens group has advanced on the optical axis. FIGS. 5 and 6 are one of the retractable lens groups, for example, a first retractable lens holding frame for the third lens group, a first retractable lens moving frame, and a retracted for driving the retractable lens group. It is the perspective view which looked at each different operation state which shows the principal part of a lens drive mechanism from a different direction. FIG. 7 is a perspective view showing in detail the vicinity of the cam portion of the retractable lens moving frame for the third lens group, and FIG. 8 shows a lead screw and a part of the drive mechanism for the third lens group. It is a perspective view which shows a female screw member. FIG. 9 is a development view showing the cam shape of the cam portion of the retractable lens moving frame for the third lens group and the sliding contact state of the cam follower portion of the female screw member that is in sliding contact with the cam portion. f) shows different states.

  The lens barrel shown in FIGS. 1 to 9 includes a fixed frame 1, a rotating cylinder 2, a first retracting lens group (third lens group) 3, a second retracting lens group (fourth lens group) 4, and a first lens group. The retractable lens holding frame 31, the first retractable lens moving frame 32, the main shaft 33, the compression torsion spring 34, the female screw member 35, the motor 36, the gear group 37, the lead screw 38 and the auxiliary shaft 39. 3 to 6 specifically show the configuration mainly related to the first retractable lens group 3 that is the third lens group, the second retractable lens group 4 that is the fourth lens group is also shown. 4, a second retractable lens holding frame 41, a second retractable lens moving frame 42 and a countershaft 49, which are substantially the same as those in the case of the first retractable lens group 3, and clearly illustrated. However, it includes a main shaft, a compression torsion spring, a female screw member, a motor, a gear group, a lead screw and the like related thereto. Further, although not clearly shown, the first lens group and the second lens group are provided inside the rotary cylinder 2 and the like.

The first retractable lens group unit, which is the third lens group mainly shown in FIGS. 3 and 4, is a third lens group, that is, the first retractable lens group 3 and the first retractable lens group 3 that holds the first retractable lens group 3. One retractable lens holding frame 31, a first retractable lens moving frame 32 for moving the first retractable lens holding frame 31 by a turning operation, and a main shaft 33 serving as a rotation center of the first retractable lens moving frame 32. A compression torsion spring 34 that applies a rotational force to the first retracting lens moving frame 32 for a rotating operation, and a female screw member 35 including a cam follower portion that appropriately controls the operation of the first retracting lens moving frame 32 , A motor 36 as a drive source of the female screw member 35, a gear group 37 that transmits the rotational driving force of the motor 36, and a lead screw that is rotationally driven by a rotational force applied from the motor 36 via the gear group 37. 38 and a secondary shaft 39 that regulates the rotation range of the first retractable lens moving frame 32 toward the optical axis and is a rotation stopper for positioning the first retractable lens group 3 on the optical axis. is doing. In this embodiment, a mechanism based on substantially the same principle as that of the first retractable lens group 3 is used for the fourth lens group, that is, the second retractable lens group 4.
Here, with reference to FIG. 14 to FIG. 16, an example in the case of adopting the configuration shown in Patent Document 4 for a conventional retractable lens mechanism will be described in detail. FIG. 14 shows a retractable lens moving frame 132 of the retractable lens group (third lens group) (corresponding to the lens holding frame 31 in the patent document 4 which means the whole integrated structure of the lens holding frame and the lens moving frame). FIG. 15 is a perspective view showing a lead screw 138 (corresponding to the lead screw 34 in Patent Document 4) and a female screw member 135 (corresponding to the female screw member 35 in Patent Document 4).

  In FIG. 14, a crank-shaped retractable lens moving frame 132 that rotates a retractable lens retaining frame (not shown in FIG. 14) that retains the retractable lens group (third lens group) has a main shaft (see FIGS. 3 and 3). A cam portion protrudes from the outer peripheral surface of a cylindrical portion that functions as a bearing that is rotatably supported by a shaft (corresponding to a main shaft 33 in FIG. A contact surface 132b (corresponding to the front engagement portion 31d in Patent Document 4) is formed. In FIG. 15, the female screw member 135 (corresponding to the female screw member 35 in Patent Document 4) is screwed to the lead screw 138 (corresponding to the lead screw 34 in Patent Document 4), and the cam of the retractable lens moving frame 132 is engaged. A cam follower portion 135a that abuts and slides on the surface 132a and a rotation stop projection 135b that engages with a rotation stop slit (not shown) protrude outward. The female screw member 135 moves forward and backward along the lead screw 138 by the rotation of the lead screw 138 driven by a motor for driving the retractable lens group (corresponding to the motor 36 in FIGS. 3 and 4).

FIG. 16 shows a developed view of a conventional cam portion and cam follower portion similar to Patent Document 4, and the alternate long and short dash line indicates the optical axis direction. Thus, the cam mechanism in the lens operating mechanism (or lens operating mechanism) for inserting / removing the retractable lens group is a one-sided contact, and the retracted state when the lens is stored changes to the inserted state for normal photographing. The transition is made by the elastic force of an elastic member such as a compression torsion spring (corresponding to the compression torsion spring 34 in FIGS. 3 and 4), and the transition to the retracted state is made by the cam mechanism to make the retractable lens moving frame elastic. On the other hand, the retractable lens group is moved. At this time, the retractable lens group is moved by rotating or sliding the retractable lens moving frame. In FIG. 16, a white portion showing only a contour is a cam portion having a cam surface 132 a and a contact surface 132 b that are formed to protrude from the cylindrical portion of the retractable lens moving frame 132, and a hatched portion is a female screw This is a cam follower portion 135 a formed to project from the member 135.
FIG. 16A shows the positional relationship between the cam surface 132a and the cam follower portion 135a when the retracting lens group is in the retracted state. The cam follower 135a is moved by moving the female screw member 135 by the driving force based on the rotation of the lead screw 138. Moves to the left in the figure. When the state shown in FIG. 16B is passed, the retractable lens moving frame 132 starts rotating, and the retractable lens group is inserted and moved in the direction toward the optical axis.

In the state of FIG. 16C, the retractable lens moving frame 132 is elastically urged in the insertion direction by the compression torsion spring, so that the cam surface 132a on the retractable lens moving frame 132 always contacts the cam follower portion 135a. Follow and touch. Then, after the retractable lens moving frame 132 is locked by the auxiliary axis for positioning the optical axis position (corresponding to the auxiliary axis 39 in FIGS. 3 and 4) and stopped from rotating, the retractable lens moving frame 132 in FIG. Thus, the front surface of the cam follower portion 135a contacts the contact surface 132b, and the retractable lens moving frame 132 is driven in the direction along the optical axis.
However, at this time, the retractable lens moving frame 132 may not move in the insertion direction due to some trouble such as contact with other parts or friction. In such a case, in the conventional configuration, the cam surface 132a and the cam follower portion 135a are separated as shown in FIG. 16 (d), and the contact surface 132b is different from FIG. 16 (f) as shown in FIG. 16 (e). It will come into contact with different places. In this case, the retractable lens moving frame 132 is not rotated, and the third lens group, which is the retractable lens group, is not located on the optical axis. I can't. In addition, in this case, the retractable lens group exists at an indefinite position between the retracted storage position and the optical axis, and at least a part of the retractable lens group, the retractable lens holding frame, and the retractable lens moving frame are other There is a risk of interfering with the mechanical parts, hindering the operation and damaging the parts.

In contrast, in the first embodiment of the present invention, the details of the retractable lens moving mechanism are shown in FIGS. 5 and 6, the details of the retractable lens moving frame 32 are shown in FIG. 7, and the female screw member is shown in FIG. 35 and the details of the lead screw 38 are shown. FIG. 9 is a development view of the cam portion of the retractable lens moving frame 32 and the cam follower portion 35a of the female screw member 35 in this embodiment.
That is, in FIGS. 5 to 9, the third lens group 3 as a retractable lens group is held by a cylindrical retractable lens holding frame 31, and the retractable lens holding frame 31 is bent in a crank shape. The moving frame 32 is integrally held. The retractable lens moving frame 32 has a cam portion protruding from an outer peripheral surface of a cylindrical portion that functions as a bearing that is rotatably supported by the main shaft 33. The cam portion has a conventional cam surface 132a and a contact surface. A cam surface 32c for forced insertion is formed in addition to the cam surface 32a and the abutting surface 32b for normal operation which are substantially the same as 132b.

The female screw member 35 is screwed into a lead screw 38 fixedly arranged in parallel with the main shaft 33, and is connected to a cam surface 32a for normal operation and a cam surface 32c for forced insertion of the cam portion of the retractable lens moving frame 32. A cam follower portion 35a that abuts and slides, and a rotation stop projection 35b (see FIGS. 5 and 8) that engages with a rotation stop slit (not shown) are formed to protrude outward. The lead screw 38 is driven to rotate through a gear group 37 by a motor 36 for driving the retractable lens group. As the lead screw 38 rotates, the female screw member 35 moves forward and backward along the lead screw 38.
The compression torsion spring 34 has a main shaft 33 inserted through a coiled inside, one end fixed to a fixing member 51 fixed to the fixed frame 1 by adhesion or the like, and the other end locked to the retractable lens moving frame 32. . The compression torsion spring 34 always urges the retractable lens moving frame 32 so as to rotate in a direction approaching the optical axis about the main shaft 33.
Note that when the retractable lens holding frame 31 is fixed to the retractable lens moving frame 32, the relative eccentric position of the both can be adjusted as appropriate so as to be fixed by bonding or the like. It is possible to compensate for the relative positional deviation between the optical axis of another lens group such as one lens group and the second lens group and the main shaft 33 that pivotally supports the retractable lens moving frame 32.

That is, in this embodiment, as shown in FIGS. 5 to 7, the cam surface 32 a for normal operation formed on the outer peripheral surface of the cylindrical portion through which the main shaft 33 of the retractable lens moving frame 32 is inserted and the contact surface In addition to the surface 32b, a cam surface is formed by providing a cam surface 32c for forced insertion that is opposed to the normal operation cam surface 32a in a substantially similar shape. Further, the shape of the cam follower portion 35a of the female screw member 35 is substantially diamond-shaped as shown in FIG. FIG. 5 shows a storage state in which the cam follower portion 35a of the female screw member 35 is engaged with the cam portion of the lens moving frame 32 in the storage state. In FIG. 6, the retractable lens moving frame 32 rotates to a predetermined position, the cam follower portion 35a of the female screw member 35 comes into contact with and engages with the contact surface 32b, and the retractable lens moving frame 32 is moved along the optical axis by the female screw member 35. The driving state is shown.
FIG. 9 is a developed view showing the cam shape of the cam portion of the retractable lens moving frame 32 of the third lens group and the sliding contact state of the cam follower portion 35a of the female screw member 35 that is in sliding contact with the cam portion. In the state, when the female screw member 35 is extended toward the object side by the rotation of the lead screw 38 from the retracted state of the retractable lens group shown in FIG. 9A, the retractable lens moving frame 32 causes the retractable lens group 3 to be on the optical axis. Since it is urged by the compression torsion spring 34 so as to approach, the state of FIG. 9 (b) is passed through the state of FIG. 9 (c) to the state of FIG. 9 (f), and the cam follower portion 35a is brought into contact with the contact surface. 32b is contacted.

  However, at this time, the retractable lens moving frame 32 may not move in the insertion direction due to some trouble such as contact with other parts or friction. In such a case, in the configuration of this embodiment, as shown in FIG. 9 (d), the cam follower portion 35a moves the retractable lens moving frame 32 with a slight delay by the action of the cam surface 32c for forced operation. Is forcibly moved in the direction of insertion on the optical axis. In many cases, the obstacle in the rotation operation of the retractable lens moving frame 32 is caused by contact with other parts or friction. For this reason, as shown in FIG. 9 (e), if the retractable lens moving frame 32 is forcibly rotated a little, the problem of contact with other parts and friction are solved, and the same as in the case of normal operation. The state shown in FIG. Accordingly, the retractable lens moving frame 32 rotates to the normal position, and the third lens group 3 that is the retractable lens group is positioned on the optical axis, so that an imaging optical system is formed and appropriate photographing can be performed. Thus, when the retractable lens moving frame 32 does not perform the insertion operation on the optical axis, the cam follower 35a comes into contact with the cam surface 32c for forced insertion as shown in FIG. 9D, and the cam follower portion 35a is further moved. When driven, the retractable lens moving frame rotates along the forcibly inserted cam surface 32c, and finally the cam follower portion 35a contacts the correct position of the contact surface 32b as shown in FIG. 9 (f).

As described above, the cam surface 32a for normal operation is added to the outer peripheral surface of the cylindrical portion through which the main shaft 33 of the retractable lens moving frame 32 is inserted, in addition to the cam surface 32a and the contact surface 32b for normal operation. When the forcibly inserted cam surface 32c is provided so as to be opposed to each other in a substantially similar shape to form the cam portion, the retractable lens is compared with the conventional shape of only the normal operation cam surface 32a and the contact surface 32b. The shape of the moving frame 32 is slightly complicated. For this reason, when the whole is formed by integral molding, if the cost increases, for example, as shown in FIG. 10, the protruding member P2 that forms the cam surface 32c for forced insertion is formed separately, This part may be omitted and integrated with the retractable lens moving frame member P1 having only the cam surface 32a and the contact surface 32b for normal operation integrally molded. In this case, as shown in the drawing, positioning convex portions and concave portions (or holes) may be formed on both sides of the joint portion between the retractable lens moving frame member P1 and the protruding portion member P2.
In the above description, only the third lens group, which is the first retractable lens group, has been described in detail as the retractable lens group. However, when the fourth lens group is included as the second retractable lens group, the fourth lens is used. What is necessary is just to comprise the structure which concerns on a group substantially the same as the case of the 3rd lens group mentioned above.

Next, a second embodiment of the lens barrel according to the present invention will be described. FIGS. 11-13 has shown the structure of the principal part of 2nd Embodiment of the lens barrel which concerns on this invention. 11 and 12 are one of the retractable lens groups, for example, a first retractable lens holding frame for the third lens group, a first retractable lens moving frame, and a retracted for driving the retractable lens group. It is the perspective view which looked at each different operation state which shows the principal part of a lens drive mechanism from a different direction. FIG. 13 shows the cam shape of the cam portion of the retractable lens moving frame for the third lens group in the configuration shown in FIGS. 11 and 12 and the sliding contact state of the cam follower portion of the female screw member that is in sliding contact with the cam portion. FIG.
That is, in FIGS. 11 to 13, the cylindrical retractable lens holding frame 31 of the third lens group which is the retractable lens group is integrally held by the retractable lens moving frame 32 ′ bent in a crank shape. . The retractable lens moving frame 32 ′ has a cam portion protruding from an outer peripheral surface of a cylindrical portion that functions as a bearing rotatably supported by the main shaft 33, and the cam portion has a cam surface 32 a for normal operation, A contact surface 32b and a forced insertion cam surface 32c are formed, and a recess 32d is formed at the feeding side end corresponding to the object side of the cylindrical portion behind the forced insertion cam surface 32c. ing.

The female screw member 35 is screwed into a lead screw 38 disposed in parallel with the main shaft 33, and is connected to the cam surface 32a for normal operation and the cam surface 32c for forced insertion of the cam portion of the retractable lens moving frame 32 '. A cam follower portion 35a that abuts and slides and a rotation stop projection 35b that engages with a rotation stop slit (not shown) are formed to project outward. As the lead screw 38 rotates, the female screw member 35 moves forward and backward along the lead screw 38. The compression torsion spring 34 has a main shaft 33 inserted through the inside of a coil, one end 34a is fixed to a fixing member 51 fixed to the fixed frame 1 by an adhesive 52 or the like, and the other end 34b is connected to the retractable lens moving frame 32 '. It is locked. The compression torsion spring 34 always urges the retractable lens moving frame 32 ′ so as to rotate in the direction approaching the optical axis about the main shaft 33.
Thus, by forming the recess 32d behind the forced insertion cam surface 32c, it is possible to secure a fixing space when the one end 34a of the compression torsion spring 34 is fixed to the fixing member 51 with an adhesive or the like. it can.

Since the cam surface for forced insertion is provided in the configuration as described in detail above, the retractable lens can be surely moved even when the retractable lens moving frame cannot be inserted on the optical axis due to some obstacle. It becomes possible to insert groups.
In addition, the cam surface for normal operation and the cam surface for forced insertion for normal insertion / removal operation are integrally formed, so that the distance between both cams can be accurately formed without increasing the distance. The occupied space based on the arrangement of these cam surfaces can be reduced.
By integrally molding the cam surface for normal operation and the cam surface for forced insertion together with the retractable lens moving frame, the retractable lens moving frame can be operated smoothly.
An optical system can always be established by forcibly operating the retractable lens moving frame when it becomes inoperable due to some obstacle.
By making the cam surface for forcible insertion substantially the same shape as the cam surface for normal operation, the retracting lens moving operation mechanism can be formed with a minimum space.
When forced insertion is not required, the cam surface for forced insertion is not in contact with the cam follower, so the cam follower is in sliding contact with only the cam surface for normal operation. it can.

By retracting the lens group with the smallest lens diameter, it is possible to reduce the retract space, and by retracting the lens group with low eccentricity sensitivity, the influence on the image quality is minimized. be able to.
Between the lens groups contributing to zooming in the plurality of lens groups, an aperture having a variable aperture diameter is provided in at least one place, and the lens group on the image plane side with respect to the aperture is retracted. The moving distance between the storage state and the photographing state can be shortened, and a simple mechanism can be used.
By making the retractable lens holding frame decentered and fixed to the retractable lens moving frame, the requirement for dimensional accuracy of the retractable lens moving frame is relaxed, and the image quality can be easily improved by adjusting the position of the retractable lens holding frame. Is possible.
By providing the cam surface for forced insertion, the retractable lens group can be reliably inserted even when the retractable lens moving frame cannot be inserted on the optical axis due to some obstacle.
By forming the recess behind the forcibly inserting cam surface, it is possible to easily secure a fixed space on the fixed side of the biasing member that biases the retractable lens moving frame.

In order to explain the configuration of the lens barrel according to the first embodiment of the present invention, a perspective view schematically showing the external appearance of the main part of the lens barrel in a state where the lens group is retracted and housed on the fixed frame side. FIG. FIG. 2 is a perspective view schematically showing an external appearance of a main part in a state where a lens group protrudes from a fixed frame to enable photographing in order to explain the configuration of the lens barrel in FIG. 1. FIG. 2 is a perspective view schematically illustrating an internal structure of the lens barrel of FIG. 1 and a retracting mode of a retracting lens group configured to retract from an optical axis among a plurality of lens groups. FIG. 2 is a perspective view schematically showing an internal structure of the lens barrel of FIG. 1, in which a retractable lens group configured to retract from the optical axis among a plurality of lens groups has advanced on the optical axis. . In order to describe the configuration of the lens barrel of FIG. 1 in more detail, a perspective view showing essential parts such as a retractable lens moving frame, a main shaft, a compression torsion spring, a lead screw and a female screw member constituting a mechanism for moving the retractable lens group. FIG. In order to explain the configuration of the lens barrel in FIG. 1, a retracting lens moving mechanism including a retracting lens moving frame, a main shaft, a compression torsion spring, a lead screw, a female screw member, and the like is schematically shown when viewed from other directions. It is a perspective view. FIG. 2 is a perspective view schematically showing a detailed configuration of a retractable lens moving frame in order to explain the configuration of the lens barrel of FIG. 1. FIG. 2 is a perspective view schematically showing a detailed configuration of a lead screw and a female screw member in order to explain the configuration of the lens barrel of FIG. 1. FIG. 2 is a development view illustrating a cam shape of a cam portion of a retractable lens moving frame and a sliding contact state of a cam follower portion of a female screw member that is in sliding contact with the cam portion in order to explain the configuration of the lens barrel of FIG. ) To (f) show different states. FIG. 2 is a perspective view schematically showing a specific configuration of an example of a retractable lens moving frame in order to explain the configuration of the lens barrel of FIG. 1. In order to describe the configuration of the lens barrel according to the second embodiment of the present invention, a retractable lens moving frame, a main shaft, a compression torsion spring, a lead screw, a female screw member, and the like constituting a mechanism for moving the retractable lens group It is a perspective view which shows the principal part. FIG. 12 is a perspective view schematically illustrating a retractable lens moving mechanism including a retractable lens moving frame, a main shaft, a compression torsion spring, and the like for explaining the configuration of the lens barrel of FIG. 11. FIG. 12 is a development view illustrating the cam shape of the cam portion of the retractable lens moving frame and the sliding contact state of the cam follower portion of the female screw member that is in sliding contact with the cam portion in order to explain the configuration of the lens barrel of FIG. 11. FIG. 6 is a perspective view schematically showing a detailed configuration of a conventional retractable lens moving frame in order to explain a configuration of a conventional lens barrel. In order to explain the configuration of a conventional lens barrel, it is a perspective view schematically showing a detailed configuration of a conventional lead screw and female screw member. In order to explain the configuration of a conventional lens barrel, it is a development view showing the cam shape of the cam portion of the retractable lens moving frame and the sliding contact state of the cam follower portion of the female screw member that is in sliding contact with the cam portion, (a) ~ (F) show different states.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed frame 2 Rotating cylinder 3 1st retracting lens group (3rd lens group)
4 Second retractable lens group (fourth lens group)
Reference Signs List 31 First retractable lens holding frame 32 First retractable lens moving frame 32 'Retractable lens moving frame 32a Normal operation cam surface 32b Forced insertion cam surface 33 Main shaft 34 Compression torsion spring 35 Female screw member 36 Motor 37 Gear group 38 Lead screw 39 Secondary shaft 41 Second retractable lens holding frame 42 Second retractable lens moving frame 49 Secondary shaft 51 Fixing member 52 Adhesive 32a Cam surface 32b for normal operation 32b Contact surface 32c Cam surface 32d for forced insertion Concave part 35a Cam follower part 35b Anti-rotation projection part P1 Retraction lens moving frame member P2 Projection part member

Claims (13)

In a lens barrel that is in a photographing state by moving at least a part of the plurality of lens groups to the object side from a retracted state in which at least a part of the plurality of lens groups is retracted to store the lens group,
A plurality of lens holding frames for holding the plurality of lens groups for each lens group;
A movable lens barrel holding the lens holding frame inside;
Lens holding frame driving means for driving the lens holding frame via the movable lens barrel;
The lens holding frame is
In the photographing state, all the lens groups are positioned on the same optical axis, and in the retracted state, the at least one lens group is held so that at least one lens group is retracted outside the inner diameter of the movable lens barrel. A retractable lens holding frame;
A lens barrel including a retractable lens moving frame for holding and moving the retractable lens holding frame,
The retractable lens moving frame is configured such that the at least one lens group is inserted into and removed from the optical axis via the retractable lens holding frame, and the at least one lens group is moved on the optical axis. Provided,
The retracting lens operating mechanism is
A normal operation cam for normal insertion / removal operation with respect to the optical axis;
A forced insertion cam for forcibly moving toward the optical axis;
A lens barrel comprising a driving cam follower that engages with these cams.   The lens barrel according to claim 1, wherein the normal operation cam and the forced insertion cam are formed separately.   2. The lens barrel according to claim 1, wherein the normal operation cam and the forced insertion cam are integrally formed on the same member.   The lens barrel according to claim 1 or 3, wherein the normal operation cam and the forced insertion cam are formed integrally with the retractable lens moving frame.   The forcible insertion cam is a cam for forcible insertion when the at least one lens group is inserted on the optical axis and the insertion operation is hindered due to some trouble. The lens barrel according to any one of claims 1 to 4.   6. The lens barrel according to claim 1, wherein the forcibly inserting cam has a shape substantially similar to the normal operation cam.   The lens barrel according to any one of claims 1 to 6, wherein the forcibly inserting cam is not in contact with the cam follower in the retracted state in which the retractable lens moving frame is in the retracted position. .   The lens group held by the retractable lens holding frame is at least one of a lens group having the smallest lens diameter among the plurality of lens groups and a lens group having the lowest decentering sensitivity among the plurality of lens groups. The lens barrel according to any one of claims 1 to 7, wherein:   Between the lens groups contributing to zooming in the plurality of lens groups, there is provided at least one stop having a variable aperture diameter, and the lens group held by the retractable lens holding frame is more image plane than the stop. The lens barrel according to claim 1, wherein the lens barrel is a side lens group.   The retractable lens holding frame and the retractable lens moving frame are configured such that the retractable lens holding frame can be fixed by being relatively decentered on a surface where the optical axes perpendicularly intersect the retractable lens moving frame. The lens barrel according to any one of claims 1 to 9, wherein:   The retracting lens moving frame has a concave portion for attaching an urging member for generating an operation force for an insertion operation on the optical axis by the normal operation cam. 5. The lens barrel according to claim 3, wherein the lens barrel is formed so as to avoid the position of the cam for normal operation.   A camera comprising the lens barrel according to any one of claims 1 to 11 as an imaging optical system.   A portable information terminal device comprising the lens barrel according to any one of claims 1 to 11 as an imaging optical system of a camera function unit.

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