JP2008268605A - Lens barrel and camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a lens barrel which supports an optical system. <P>SOLUTION: The lens barrel 3 is provided with a master flange 31, a fixed frame 33, a drive frame 34, and a third lens frame 35. A focus lens L3 is provided in the third lens frame 35. A retreat frame is supported by a fixed member so as to rotate relative to the fixed member, and has a second rotary shaft arranged on the outside in the radial direction of a rotating member. The third lens frame 35 can rotate relative to the fixed frame 33 between an insertion position Q1 and a retreat position Q2. The drive frame 34 has a drive projection 34e capable of abutting on the third lens frame 35. The drive frame 34 guides the third lens frame 35 from the insertion position Q1 to the retreat position Q2 by the drive projection 34e, and the third lens frame 35 moves in a Y-axis direction while rotating relative to the fixed frame 33 in such a state that it is positioned at the retreat position Q2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lens barrel and a camera, and more particularly to a lens barrel for supporting an optical system and a camera including the same.

Conventionally, an optical system having at least one optical element has been used in various apparatuses.
An example of a device equipped with an optical system is a camera. An imaging optical system used for a camera has a plurality of lenses. By changing the distance between the lenses, the focal length of the imaging optical system can be changed, and the zoom magnification of the imaging optical system can be adjusted. For example, the imaging optical system is supported by a lens barrel having a plurality of support frames.
On the other hand, there is a demand for miniaturization in any device. For an apparatus equipped with an optical system, there is a demand for downsizing the lens barrel that can contribute to downsizing of the entire apparatus.
Thus, for example, in the camera field, a lens barrel that retracts a part of the optical element out of the optical path has been proposed (see, for example, Patent Documents 1 and 2).
JP-A-11-326737 JP 2006-30297 A

In the lens barrel described in Patent Document 1, the teleconverter 2 is retracted out of the optical path using the rotational motion of the cam can 1.
However, in this barrel, the cam can 1 that drives the teleconverter 2 does not move in the direction along the optical axis. That is, this barrel is not a so-called collapsible barrel. For this reason, even if the teleconverter 2 can increase the magnification, the lens barrel cannot be reduced in size.
In the lens barrel described in Patent Document 2, the third lens group 16 is retracted out of the optical path.
However, in this barrel, the third lens group 16 rotates toward the first lens group 12 and the second lens group 14. For this reason, a wide movement space is required around the third lens group 16, and miniaturization of the lens barrel is hindered.
Thus, the conventional lens barrel is required to be further downsized.

  An object of the present invention is to reduce the size of a lens barrel that supports an optical system.

  A lens barrel according to a first invention is a lens barrel for supporting an optical system. The lens barrel includes a fixing member, an annular rotating member, and a retraction frame. The rotating member is supported by the fixing member so as to be rotatable around the first rotation axis with respect to the fixing member. The retraction frame is a member provided with an optical element included in the optical system. The retraction frame is supported by the fixing member so as to be rotatable with respect to the fixing member, and has a second rotating shaft disposed on the outer side in the radial direction of the rotating member. The retraction frame is rotatable with respect to the fixed member between an insertion position where the optical element is inserted into an effective optical path of the optical system and a retraction position where the retraction frame is disposed radially outside the rotation member. . The rotating member has a contact portion that can contact the retracting frame in the rotation direction of the rotating member. The rotating member guides the retracting frame from the insertion position to the retracted position by the contact portion, and moves in the direction along the first rotation axis while rotating with respect to the fixed member in a state where the retracting frame is disposed at the retracting position. .

In this barrel, when the rotating member rotates with respect to the fixed member, the contact portion of the rotating member contacts the retracting frame, and the retracting frame is guided from the insertion position to the retracted position. In addition, the rotating member moves in the direction along the first rotation axis with respect to the fixed member in a state where the retracting frame is disposed at the retracted position. For this reason, in the collapsible lens barrel in which the rotating member moves in the direction along the first rotation axis with respect to the fixed member, it is not necessary to provide a storage space for the retractable frame in the retracted state inside the rotating member in the radial direction. . Thereby, the dimension of the fixed member or the rotating member in the direction along the first rotating shaft can be shortened, and the size of the lens barrel can be reduced.
Here, “optical system” means an optical system including at least one optical element. Examples of the optical system include an imaging optical system including a plurality of lenses. “Optical element” means an optical component made of an optical material. Examples of the optical element include a lens, a prism, a mirror, and a filter.

In addition, the “collapsed lens barrel” refers to the portability of the device when not in use, and the relative dimensions of the multiple members that make up the lens barrel when not in use This means a lens barrel that is smaller than that. Further, the lens barrel may be configured such that the actuator applies a driving force to the rotating member, or may be configured so that the user applies the driving force to the rotating member.
The lens barrel according to a second aspect of the present invention is the lens barrel according to the first aspect of the present invention, wherein the operating range of the rotating member in the rotational direction relative to the fixed member has a collapsible operating range and a rotating operating range. The collapsible operation range is a range in which the rotating member rotates around the first rotation axis while moving in the direction along the first rotation axis with respect to the fixed member. The rotation operation range is a range in which the rotation member rotates around the first rotation axis without moving in the direction along the first rotation axis with respect to the fixed member. In the rotational operation range, the retraction frame is guided from the insertion position to the retraction position by the rotation member. In the retracting operation range, the retracting frame is held radially outward of the rotating member by the rotating member.

A lens barrel according to a third aspect of the present invention is the lens barrel according to the second aspect of the present invention, further comprising an elastic member that applies torque to the retraction frame so as to rotate from the retraction position to the insertion position. In the retracting operation range, the retracting frame is pressed against the radially outer portion of the rotating member by the torque from the elastic member.
A lens barrel according to a fourth invention is the lens barrel according to the third invention, wherein the fixing member has a stopper. The stopper frame comes into contact with the stopper in the rotational direction at the insertion position.
A lens barrel according to a fifth invention is the lens barrel according to the fourth invention, wherein the rotational operation range has a first rotational operation range and a second rotational operation range. The first rotation operation range is a range in which the contact portion can contact the retraction frame in the rotation direction. The second rotation operation range is a range in which the contact portion cannot contact the retraction frame in the rotation direction.

A lens barrel according to a sixth invention is the lens barrel according to the fifth invention, wherein the retracting frame has a bearing portion and a retracting frame main body. The bearing portion is disposed on the radially outer side of the rotating member and is rotatably supported by the fixed member. The retractable frame body is fixed to the bearing portion and provided with an optical element. When viewed from the direction along the first rotation axis, the retracting frame body is disposed on the radially outer side of the rotating member in a state where the retracting frame body is in contact with the contact portion in the radial direction of the rotating member.
A lens barrel according to a seventh invention is the lens barrel according to the sixth invention, wherein the retracting frame body has a sliding portion. The sliding part comes into contact with or slides on the contact part. When viewed from the direction along the first rotation axis, the sliding portion is curved along the radially outer portion of the rotating member in a state where the retracting frame main body is located at the retracted position.
According to an eighth aspect of the present invention, in the lens barrel according to the seventh aspect of the present invention, the fixing member has an accommodating portion in which the retracting frame is accommodated at the retracted position.

A lens barrel according to a ninth invention is the lens barrel according to the eighth invention, wherein the contact portion is a protrusion extending in a direction along the first rotation axis. The fixing member has a recess in which the contact portion is accommodated in a state where the rotating member is close to the fixing member.
A lens barrel according to a tenth invention is the lens barrel according to the ninth invention, further comprising a first actuator, a retraction sensor, and a control unit. The first actuator is provided on the fixed member and rotationally drives the rotating member. The retraction sensor detects whether or not the retraction frame is arranged at the retraction position. The control unit controls the operation of the first actuator based on the detection result from the retract sensor. The control unit limits the movement of the rotating member in the direction along the first rotation axis based on the detection result that the retracting frame is not disposed at the retracted position.
A lens barrel according to an eleventh invention is the lens barrel according to the tenth invention, and further includes a second actuator. The operation of the second actuator is controlled by the control unit, and drives the retracting frame in the direction along the first rotation axis. The operating range of the retracting frame in the direction along the first rotation axis with respect to the fixed member has a first operating range and a second operating range. The first operation range is a range in which the retractable frame can contact the contact portion in the rotation direction. The second operation range is a range in which the retractable frame cannot contact the contact portion in the rotation direction. When the rotating member is disposed within the retracting operation range, the control unit limits the operation range of the retraction frame by the second actuator within the first operation range. When the rotating member is arranged in the rotation operation range, the control unit limits the operation range of the retraction frame by the second actuator within the second operation range.

A camera according to a twelfth aspect includes a lens barrel according to any one of the first to eleventh aspects, an optical system, an imaging unit, and an exterior part. The optical system is held by a lens barrel. The imaging unit captures an optical image of a subject formed by the optical system. The exterior part holds the lens barrel.
Since this camera includes the lens barrel according to any one of the first to eleventh inventions, it is possible to reduce the size.

  Since the lens barrel and the camera according to the present invention have the above-described configuration, downsizing can be realized.

Hereinafter, a lens barrel and a camera according to the present invention will be described with reference to the drawings.
<First Embodiment>
[1: Overview of digital camera]
A digital camera 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2 are schematic perspective views of the digital camera 1. FIG. 1 shows a case where the lens barrel 3 is in a photographing state.
The digital camera 1 is a camera for acquiring an image of a subject. The digital camera 1 is equipped with a multistage retractable lens barrel 3 for high magnification and miniaturization. The lens barrel 3 is mainly characterized in that the third lens frame 35 is retracted to the outside of the drive frame 34 in the radial direction. The configuration of the third lens frame 35 will be described later.

In the following description, the six surfaces of the digital camera 1 are defined as follows.
The surface facing the subject side when taking a picture with the digital camera 1 is the front surface, and the opposite surface is the back surface. Up and down vertical direction of the subject and rectangular image captured by the digital camera 1 (generally, aspect ratio (ratio of long side to short side) is 3: 2, 4: 3, 16: 9, etc.) When photographing is performed so as to coincide with each other, a surface facing upward in the vertical direction is defined as a top surface, and a surface on the opposite side is defined as a bottom surface. Further, when shooting is performed so that the vertical direction of the subject and the vertical direction of the rectangular image captured by the digital camera 1 coincide with each other, the left side when viewed from the subject side is the left side, and vice versa. The side surface is the right side surface. The above definition does not limit the usage posture of the digital camera 1.
According to the above definition, FIG. 1 is a perspective view showing the front surface, the top surface, and the right side surface.

Note that not only the six surfaces of the digital camera 1 but also the six surfaces of each component arranged in the digital camera 1 are defined in the same manner. In other words, the above definition is applied to the six surfaces of each component member arranged in the digital camera 1.
Further, as shown in FIG. 1, a three-dimensional orthogonal coordinate system (right-handed system) having a Y axis parallel to an optical axis A of an imaging optical system O (described later) is defined. According to this definition, the direction from the back side to the front side along the optical axis A is the Y axis positive direction, and the direction orthogonal to the optical axis A and from the right side to the left side is the X axis positive direction. Yes, the direction perpendicular to the X-axis and Y-axis and from the bottom surface side to the top surface side is the Z-axis positive direction.
Hereinafter, in each drawing, it demonstrates on the basis of this XYZ coordinate system. That is, the X-axis positive direction, the Y-axis positive direction, and the Z-axis positive direction in each drawing indicate the same direction.

[2: Overall configuration of digital camera]
As shown in FIGS. 1 and 2, the digital camera 1 mainly holds an exterior portion 2 that accommodates each unit, an imaging optical system O that forms an optical image of a subject, and the imaging optical system O so as to be movable. And a lens barrel 3. The imaging optical system O is an example of an optical system. The lens barrel 3 is an example of a barrel that supports an optical system.
The imaging optical system O is composed of a plurality of lens groups, and the plurality of lens groups are arranged in a state of being aligned in the Y-axis direction. The optical axis A of the imaging optical system O extends in the Y-axis direction. The lens barrel 3 is a multistage collapsible type and is supported by the exterior portion 2. The plurality of lens groups are supported by the lens barrel 3 so as to be relatively movable in the Y-axis direction. Details of the configuration of the lens barrel 3 will be described later.

The exterior unit 2 includes, for example, a CCD unit (not shown) as an imaging unit that performs photoelectric conversion on an optical image, and an image recording unit 9 that records an image acquired by the CCD unit. Yes. A liquid crystal monitor 8 for displaying an image acquired by the CCD unit is provided on the back surface of the exterior portion 2.
A release button 4, an operation dial 5, a power switch 6, and a zoom adjustment lever 7 are provided on the upper surface of the exterior portion 2 so that the photographer can perform operations such as an imaging operation. The release button 4 is a button for the photographer to input the exposure timing. The operation dial 5 is a dial for the photographer to make various settings regarding the photographing operation. The power switch 6 is a switch for the photographer to operate the digital camera 1 on and off. The zoom adjustment lever 7 is a lever for the photographer to adjust the zoom magnification, and is rotatable within a predetermined angle range around the release button 4.

1 and 2 show only the main configuration of the digital camera 1. FIG. For this reason, a configuration other than the above-described configuration may be provided in the digital camera 1.
[3: Configuration of lens barrel]
The overall configuration of the lens barrel 3 will be described with reference to FIGS. FIG. 3 is an exploded perspective view of the lens barrel 3. FIG. 4 is a schematic plan view of the lens barrel 3. In FIG. 3 and FIG. 4, some constituent members are omitted.
As shown in FIG. 3, the lens barrel 3 mainly includes a master flange 31 fixed to the exterior portion 2, a zoom motor 32 as a first actuator fixed to the master flange 31, and each support frame as a master flange. 31, a fixed frame 33 accommodated between them, a drive frame 34 to which the driving force of the zoom motor 32 is input, a rectilinear frame (not shown) supported by the fixed frame 33 so as to be movable in the Y-axis direction, It is composed of For example, a CCD 39 included in the CCD unit is attached to the master flange 31. For example, the zoom motor 32 is a stepping motor.

The lens barrel 3 further includes a first lens frame (not shown) that holds a first lens group (not shown) and a second lens frame (not shown) that holds a second lens group (not shown). And a third lens frame 35 as a retraction frame for holding the third lens group G3. The first lens group is, for example, a lens group having negative power as a whole, and takes in light from the subject. The second lens group is, for example, a lens group having a positive power as a whole. The third lens group G3 includes a focus lens L3 having a positive power for adjusting the focal point, for example. An imaging optical system O is constituted by the first lens group, the second lens group, and the third lens group G3.
(3.1: Fixed frame)
The fixed frame 33 is a member for guiding the drive frame 34, and constitutes a member on the fixed side of the lens barrel 3 together with the master flange 31. The fixed frame 33 is fixed to the master flange 31 with, for example, screws. The fixed frame 33 mainly includes a substantially cylindrical fixed frame main body 33a constituting a main part, a drive gear 33b rotatably supported by the fixed frame main body 33a, and a housing portion 33f in which the third lens frame 35 is housed. And is composed of.

The fixed frame main body 33a is fixed to the master flange 31, and the drive frame 34 is disposed on the inner peripheral side. The drive gear 33b is a member for transmitting the drive force of the zoom motor 32 to the drive frame 34, and is rotatably supported by the fixed frame main body 33a. The drive gear 33b meshes with the gear 32a of the zoom motor 32. On the inner peripheral side of the fixed frame main body 33a, three inclined grooves 33c and three rotating grooves 33d for guiding the drive frame 34, and a first helicoid portion 33e are formed. The inclined grooves 33c are arranged at equal intervals in the circumferential direction, and are connected to the rotating groove 33d.
The housing portion 33f is a generally box-shaped portion that protrudes in the X-axis direction from the fixed frame main body 33a, and is integrally formed with the fixed frame main body 33a. In a state where the third lens frame 35 is disposed on the outer side in the radial direction of the drive frame 34, the third lens frame 35 is accommodated in the accommodating portion 33f. A retracting sensor 38, which will be described later, is fixed to the housing portion 33f.

(3.2: Drive frame)
The drive frame 34 is a member for guiding each lens frame (not shown), and is disposed on the inner peripheral side of the fixed frame 33. The drive frame 34 is a substantially cylindrical member and can rotate around the optical axis A with respect to the fixed frame 33. The rotation axis (first rotation axis) of the drive frame 34 substantially coincides with the optical axis A. The drive frame 34 is mainly composed of a substantially cylindrical drive frame main body 34a disposed on the inner peripheral side of the fixed frame main body 33a.
Three protrusions 34d are provided on the outer peripheral side of the drive frame main body 34a. The three protrusions 34d are arranged at equal intervals in the circumferential direction. The protrusion 34d is movable in the inclined groove 33c and the rotation groove 33d of the fixed frame 33.
A gear portion 34b and a second helicoid portion 34c are formed on the outer peripheral side of the drive frame main body 34a. The gear portion 34 b meshes with the drive gear 33 b of the fixed frame 33. Thereby, the driving force of the zoom motor 32 is transmitted to the drive frame 34 via the drive gear 33b. The second helicoid part 34 c meshes with the first helicoid part 33 e of the fixed frame 33.

A drive protrusion 34e extending to the Y axis direction negative side is provided at the Y axis direction end of the second helicoid portion 34c. The drive protrusion 34e is a protrusion for rotationally driving the third lens frame 35, and protrudes from the second helicoid portion 34c to the Y axis direction negative side and radially outward.
As shown in FIG. 3, the master flange 31 is formed with an accommodation groove 31 c as a recess for accommodating the drive protrusion 34 e in the retracted state. Considering the amount of movement of the drive protrusion 34e in the rotational direction, the receiving groove 31c is long in the rotational direction. When viewed from the Y axis direction positive side, the accommodation groove 31c has an arc shape. The width of the accommodation groove 31c is longer than the radial dimension of the drive protrusion 34e.
The drive frame 34 is driven to rotate around the optical axis A (R1 direction and R2 direction) by the driving force from the zoom motor 32. For example, when shifting from the retracted state to the photographing state, the drive frame 34 is driven in the R1 direction by the zoom motor 32. As a result, the protrusion 34d moves along the inclined groove 33c of the fixed frame 33, and the drive frame 34 moves to the Y axis direction positive side while rotating with respect to the fixed frame 33. In the photographing state, the protrusion 34d moves along the rotation groove 33d, and the drive frame 34 rotates without moving in the Y axis direction with respect to the fixed frame 33. When shifting from the photographing state to the retracted state, the drive frame 34 is driven in the R2 direction by the zoom motor 32. As a result, the drive frame 34 moves to the Y axis direction negative side while rotating with respect to the fixed frame 33.

Here, the operation range of the drive frame 34 in the rotation direction (that is, the rotation angle of the drive frame 34) will be described with reference to FIG. FIG. 5 is a diagram showing the operation range of the drive frame 34 and the third lens frame 35. Each operation range C1 to C3 shown in FIG. 5 is based on a drive protrusion 34e described later.
As shown in FIG. 5, the operating range of the drive frame 34 has a retractable operating range C1, a retracting driving range C2 as a first rotating operating range, and a zooming operating range C3 as a second rotating operating range. ing. The retract drive range C2 and the zoom operation range C3 are examples of the rotation operation range. Each operation range C1 to C3 shown in FIG. 5 is based on the position of the drive protrusion 34e.
The collapsible operation range C1 and the retract drive range C2 are ranges in which the lens barrel 3 transitions from the retracted state to the photographing state. The retracted state means a state in which the lens barrel 3 is not used, and is a state in which the dimension of the lens barrel 3 in the Y-axis direction is the shortest. The shooting state means a use state of the lens barrel 3. The zoom operation range C3 is a range that is used when shooting is performed by the digital camera 1, and more specifically, is a range in which the drive frame 34 rotates when the zoom magnification is adjusted.

As shown in FIG. 5, the retraction operation range C1 is a rotation operation range of the drive frame 34 from the retraction position P1 to the retreat completion position P2. The retraction drive range C2 is a rotation operation range from the retraction completion position P2 to the wide angle position P3. The zoom operation range C3 is a rotation operation range from the wide-angle position P3 to the telephoto position P4. The retracted position P1 corresponds to a state in which the lens barrel 3 is contracted most. The retreat completion position P2 corresponds to a state in which the third lens frame 35 is disposed on the outer side in the radial direction of the drive frame 34. The wide-angle position P3 corresponds to the wide-angle end of the lens barrel 3. The telephoto position P4 corresponds to the telephoto end of the lens barrel 3. A gap H1 is secured in the rotational direction between the drive projection 34e and the third lens frame 35 at the wide-angle position P3 so that the drive projection 34e does not contact the third lens frame 35.
In the collapsing operation range C1, the protrusion 34d is guided by the inclined groove 33c, and the drive frame 34 rotates while moving in the direction along the optical axis A with respect to the fixed frame 33. In the retreat drive range C2, the protrusion 34d of the drive frame 34 is guided by the rotation groove 33d of the fixed frame 33, and the drive frame 34 rotates without moving in the direction along the optical axis A with respect to the fixed frame 33. As shown in FIGS. 3 and 5, in the retract drive range C <b> 2, the drive protrusion 34 e can contact the third lens frame 35 in the rotation direction.

In the zoom operation range C3, as in the retract drive range C2, the protrusion 34d is guided by the rotation groove 33d, and the drive frame 34 rotates without moving in the direction along the optical axis A with respect to the fixed frame 33. For example, when the drive frame 34 rotates, the first lens frame and the second lens frame move with respect to the fixed frame 33. Thus, the zoom magnification of the imaging optical system O can be adjusted by rotating the drive frame 34.
(3.3: Third lens frame)
The third lens frame 35 as a retracting frame will be described with reference to FIGS. FIG. 6 is a plan view of the third lens frame 35.
The third lens frame 35 is a member for supporting the focus lens L3 for focus adjustment, and supports the focus lens L3 so that it can be inserted into and retracted from the drive frame 34. Specifically, as shown in FIG. 5, the third lens frame 35 is supported by the master flange 31 so as to be movable and rotatable in the Y-axis direction with respect to the master flange 31. The third lens frame 35 is rotatable between the insertion position Q1 and the retracted position Q2 around the rotation axis B as the second rotation axis. The rotation axis B is substantially parallel to the optical axis A and is disposed on the outer side in the radial direction of the drive frame 34.

At the insertion position Q1, the focus lens L3 is inserted into the effective optical path of the imaging optical system O. At the insertion position Q1, the third lens frame 35 is in contact with a stopper 31b provided on the master flange 31. Accordingly, the third lens frame 35 is positioned at the insertion position Q1. At the retracted position Q2, the third lens frame 35 is retracted to the outside of the drive frame 34 in the radial direction. When viewed from the Y-axis direction, the third lens frame 35 does not overlap the drive frame 34 at the retracted position Q2. At the retracted position Q2, the focus lens L3 does not function as a part of the imaging optical system O because the focus lens L3 is not inserted into the effective optical path of the imaging optical system O.
As shown in FIGS. 3, 4 and 6, the third lens frame 35 mainly has a lens frame body 35a as a retracting frame body and a bearing portion 35c. The lens frame main body 35a is integrally formed with the bearing portion 35c. The lens frame main body 35a is supported by the bearing portion 35c so as to be rotatable with respect to the master flange 31 and movable in the Y-axis direction.

The lens frame main body 35a is a plate-like portion disposed substantially perpendicular to the Y axis, and the drive protrusion 34e and the stopper 31b can contact in the rotation direction. A focus lens L3 is fixed to one end of the lens frame main body 35a. A bearing portion 35c is integrally provided at the other end of the lens frame main body 35a. The bearing portion 35c is a cylindrical portion extending in the Y-axis direction. A shaft 31a provided on the master flange 31 is inserted into the bearing portion 35c. The bearing portion 35c can rotate around the rotation axis B with respect to the master flange 31 and can move in the Y-axis direction (direction along the rotation axis B). With these configurations, the third lens frame 35 and the focus lens L3 can rotate with respect to the master flange 31 and the fixed frame 33.
The lens frame main body 35a has a sliding portion 35b that slides with the driving protrusion 34e in the retreat driving range C2. The sliding portion 35 b includes a portion that curves along the radially outer portion of the drive frame 34. Specifically, as shown in FIG. 6, the sliding portion 35b includes a linear first sliding portion E1, an arc-shaped second sliding portion E2, an arc-shaped third sliding portion E3, have. The first sliding portion E1 is a portion that slides with the driving protrusion 34e when the third lens frame 35 is driven from the insertion position Q1 to the retracted position Q2. The second sliding portion E2 and the third sliding portion E3 are portions that slide with the driving protrusion 34e in a state where the third lens frame 35 is disposed at the retracted position Q2. The second sliding portion E2 and the third sliding portion E3 are curved along the second helicoid portion 34c of the drive frame 34.

The first sliding portion E1 and the second sliding portion E2 are portions where the drive protrusion 34e slides when the drive frame 34 rotates in the retreat drive range C2. The third sliding portion E3 is a portion where the driving protrusion 34e slides when the driving frame 34 rotates in the retracting operation range C1. For this reason, in the 3rd sliding part E3, the drive protrusion 34e slides in the rotation direction and the Y-axis direction with the sliding part 35b. A boundary portion between the second sliding portion E2 and the third sliding portion E3 is a portion where the drive protrusion 34e abuts at the retreat completion position P2.
Here, the positioning of the third lens frame 35 in the Y-axis direction will be described with reference to FIGS. 7 and 8. FIGS. 7A and 7B are diagrams illustrating the operating range of the third lens frame 35 in the Y-axis direction. FIG. 7A is a diagram illustrating a state of the third lens frame 35 at the first position U1. FIG. 7B is a diagram illustrating a state of the third lens frame 35 at the second position U2. FIG. 8 is a detailed view around the spring 37.

As shown in FIG. 7, the third lens frame 35 is movable in the Y-axis direction from the first position U1 to the second position U2. The use range U from the first position U1 to the second position U2 is a range in which the third lens frame 35 is driven in the Y-axis direction for focus adjustment of the imaging optical system O. At the first position U1, the third lens frame 35 is close to the drive frame main body 34a in the Y-axis direction. As shown in FIG. 7, at the first position U1, at least a part of the drive protrusion 34e overlaps the third lens frame 35 in the rotation direction. For this reason, when the third lens frame 35 is disposed at the first position U1, the third lens frame 35 can contact the drive protrusion 34e in the rotation direction.
As shown in FIG. 7, a support portion 31d having an outer diameter larger than that of the shaft 31a is provided at the base of the shaft 31a. A spring 37 is fitted into the shaft 31a. Specifically, as shown in FIG. 8, the spring 37 is sandwiched between the support portion 31d and the bearing portion 35c. In a state where the third lens frame 35 is disposed at the first position U1, the spring 37 is compressed in the Y-axis direction between the bearing portion 35c and the support portion 31d. For this reason, in the use range U, the bearing portion 35 c is pushed to the Y axis direction positive side by the spring 37.

As shown in FIG. 3, a focus motor 36 as a second actuator is fixed to the motor fixing portion 31 f of the master flange 31. The focus motor 36 is, for example, a stepping motor, and has a shaft 36b having a thread formed on the outer periphery. A nut 36a is screwed to the shaft 36b. The rotation of the nut 36a relative to the master flange 31 is regulated by the motor fixing portion 31f. For this reason, when the shaft 36b rotates with respect to the nut 36a, the nut 36a moves in the Y-axis direction without rotating with respect to the master flange 31.
The nut 36a is disposed on the Y axis direction positive side of the bearing portion 35c, and presses the bearing portion 35c on the Y axis direction negative side. In other words, in the usage range U, the bearing portion 35 c is pressed against the nut 36 a by the spring 37. For this reason, when the nut 36a moves in the Y-axis direction, the third lens frame 35 also moves in the Y-axis direction accordingly. In this way, the position of the third lens frame 35 in the Y-axis direction can be adjusted by the focus motor 36.

  Further, the spring 37 applies torque around the rotation axis B to the third lens frame 35 in addition to the load in the Y-axis direction. Specifically, as shown in FIG. 8, the bearing portion 35c has a first protruding portion 35d that protrudes to the Y axis direction negative side. The support portion 31d has a second protruding portion 31e that protrudes to the Y axis direction positive side. The spring 37 has a first end 37a and a second end 37b. The first end 37a is in contact with the first protrusion 35d, and the second end 37b is in contact with the second protrusion 31e. When the third lens frame 35 rotates in the R3 direction with respect to the master flange 31, the spring 37 is twisted between the bearing portion 35c and the support portion 31d. Thereby, torque can be applied to the third lens frame 35. Thus, the spring 37 has a function as a torsion spring in addition to a function as a compression spring.

As shown in FIG. 5, in the retraction range C4 from the insertion position Q1 to the retraction position Q2, for example, the spring 37 is always twisted between the bearing portion 35c and the support portion 31d. Therefore, the torque T in the R4 direction always acts on the third lens frame 35 in the retreat range C4.
At the insertion position Q1, the third lens frame 35 is pressed against the stopper 31b by the torque T. Positioning of the focus lens L3 in use is performed by the stopper 31b. As shown in FIG. 5, in a state where the third lens frame 35 is in contact with the stopper 31b, the optical axis D of the focus lens L3 is substantially coincident with the optical axis A of the imaging optical system O. Thereby, even if the posture of the digital camera 1 changes during photographing, the position of the focus lens L3 in the rotation direction with respect to the master flange 31 is stabilized, and the accuracy of focus adjustment does not decrease.

As shown in FIG. 5, when the drive frame 34 rotates in the R2 direction, the drive protrusion 34e contacts the third lens frame 35, and the third lens frame 35 is pushed in the R3 direction by the drive protrusion 34e. As a result, the third lens frame 35 rotates in the R3 direction while resisting the torque T. At this time, the drive protrusion 34e slides with the sliding part 35b of the lens frame main body 35a. When the drive frame 34 rotates in the R1 direction, the third lens frame 35 rotates in the R4 direction while being pressed against the drive protrusion 34e by the torque T. When the third lens frame 35 comes into contact with the stopper 31b, the rotation of the third lens frame 35 stops.
(3.4: Retraction sensor)
As shown in FIG. 3, the lens barrel 3 further includes a retraction sensor 38 and a control unit 10.

The retraction sensor 38 is a sensor for detecting whether or not the third lens frame 35 is disposed at the retraction position Q <b> 2, and is fixed to the housing portion 33 f of the fixed frame 33. The retraction sensor 38 is, for example, a photo sensor. The position of the retraction sensor 38 is set with reference to the retraction position Q2 of the third lens frame 35. Specifically, the position of the retraction sensor 38 is determined so that the retraction sensor 38 faces the lens frame main body 35a in the Y-axis direction in a state where the third lens frame 35 is disposed around the retraction position Q2. . Whether or not the third lens frame 35 is disposed at the retracted position Q2 can be detected by the retract sensor 38. A detection signal from the retraction sensor 38 is transmitted to the control unit 10.
(3.5: Control unit)
FIG. 9 shows a block diagram of the control unit 10. The control unit 10 is electrically connected to, for example, the zoom motor 32, the focus motor 36, the retraction sensor 38, the CCD 39, the liquid crystal monitor 8, and the image recording unit 9, and controls the operation of each unit.

Specifically, as shown in FIG. 9, the control unit 10 mainly includes a zoom motor driving unit 11, a focus motor driving unit 12, a CCD driving unit 13, a liquid crystal monitor driving unit 14, and a recording driving unit 15. And a control unit main body 16. The control unit main body 16 is electrically connected to the zoom motor driving unit 11, the focus motor driving unit 12, the CCD driving unit 13, the liquid crystal monitor driving unit 14, and the recording driving unit 15.
The control unit main body 16 has a CPU, a ROM, and a RAM, and controls the operation of each unit via each drive unit. For example, the control unit body 16 can realize various functions by reading a program stored in the ROM into the CPU. The control unit body 16 has a function of determining whether or not the third lens frame 35 is disposed at the retracted position Q2 based on a detection signal from the retracting sensor 38, and the zoom motor driving unit 11 and the focus motor based on the determination result. A function of generating a control pulse to the drive unit 12 and a function of storing the rotation angle of the drive frame 34 and the position of the third lens frame 35 in the Y-axis direction from the transmitted control pulse are realized.

The zoom motor drive unit 11 drives the zoom motor 32 according to the control pulse from the control unit main body 16. The focus motor drive unit 12 drives the zoom motor 32 according to the control pulse from the control unit main body 16. The rotation angle and rotation speed of the zoom motor 32 and the focus motor 36 are determined by the number and frequency of control pulses generated by the control unit main body 16.
The CCD drive unit 13 drives the CCD 39 in accordance with a command from the control unit main body 16. The liquid crystal monitor drive unit 14 drives the liquid crystal monitor 8 in accordance with a command from the control unit main body 16.
[4: Operation of digital camera]
The operation of the digital camera 1 will be described with reference to FIGS. Here, the operation of the drive frame 34 and the third lens frame 35 will be mainly described. 10 and 11 are explanatory views of the operation of the drive frame 34 and the third lens frame 35. FIG. FIG. 10A shows a state in which the drive frame 34 is in the zoom operation range C3. FIG. 10B and FIG. 11A show a state where the drive frame 34 is in the retract drive range C2. FIG. 11B shows a state where the drive frame 34 is in the retracting operation range C1. FIG. 12 is a diagram showing the positional relationship between the drive frame 34 and the third lens frame 35 in the Y-axis direction. FIG. 13 is an operation flowchart of the lens barrel 3 when the power switch 6 is switched from ON to OFF.

(4.1: Operation in shooting state)
When the digital camera 1 is in the photographing state (the power switch 6 is in the ON state), the drive frame 34 can rotate with respect to the master flange 31 within the zoom operation range C3. Specifically, the drive frame 34 is rotationally driven by the zoom motor 32 in accordance with the direction in which the zoom adjustment lever 7 is operated. For example, when the zoom adjustment lever 7 is operated to the telephoto side, the drive frame 34 is rotationally driven by the zoom motor 32 in the R1 direction. When the zoom adjustment lever 7 is operated to the wide angle side, the drive frame 34 is rotationally driven by the zoom motor 32 in the R2 direction. At this time, the rotation operation range of the drive frame 34 is limited within the zoom operation range C3 by the control pulse transmitted from the control unit body 16 to the zoom motor drive unit 11.
In the zoom operation range C3, the protrusion 34d is guided by the rotation groove 33d. For this reason, the drive frame 34 rotates with respect to the fixed frame 33 without moving in the direction along the optical axis A with respect to the fixed frame 33.

When the drive frame 34 rotates with respect to the fixed frame 33, for example, the first lens frame (not shown) and the second lens frame (not shown) are guided by the cam groove to the Y axis direction with respect to the fixed frame 33. Move to. Thereby, the zoom magnification of the imaging optical system O can be adjusted within a predetermined range.
When the release button 4 is pressed, for example, a defocus amount is detected by a focus detection unit (not shown). It is determined whether or not the defocus amount detected by the control unit 10 is within the allowable range. If the defocus amount exceeds the allowable value range, the third lens frame 35 is driven in the Y-axis direction by the focus motor 36 so that the defocus amount falls within the allowable value range.
At this time, the nut 36a is driven to the Y axis direction positive side by the focus motor 36, and the third lens frame 35 moves to the Y axis direction positive side together with the nut 36a. As shown in FIG. 5, a gap H <b> 1 is secured in the rotational direction between the drive protrusion 34 e and the lens frame body 35 a of the third lens frame 35. For this reason, even if the third lens frame 35 moves to the first position U1, the third lens frame 35 does not interfere with the drive protrusion 34e. By repeatedly detecting the defocus amount and driving the third lens frame 35, the defocus amount falls within the allowable range.

When the defocus amount falls within the allowable range, a shutter (not shown) is opened for a predetermined exposure time, and an optical image of the subject enters the CCD 39 via the imaging optical system O. The optical image of the subject is converted into an electric signal by the CCD 39 and the CCD driving unit 13, and the electric signal corresponding to the optical image is recorded in the image recording unit 9.
(4.2: Operation when power is off)
When the power switch 6 is switched from ON to OFF, the retracting operation of the lens barrel 3 is started. Specifically, as shown in FIG. 13, the third lens frame 35 is driven to the first position U1 by the focus motor 36, and at the same time, the drive frame 34 is rotationally driven by the zoom motor 32 to the wide angle position P3 in the R2 direction. (S1). When the driving of the third lens frame 35 and the drive frame 34 is completed, the drive frame 34 is rotationally driven in the R2 direction by the zoom motor 32 to the retract completion position P2 (S2).

  When the drive frame 34 rotates from the wide angle position P3 to the retract completion position P2, the third lens frame 35 is rotationally driven in the R3 direction from the insertion position Q1 to the retract position Q2 by the drive protrusion 34e. Specifically, as shown in FIG. 10, when the drive frame 34 rotates in the R2 direction from the wide-angle position P3, the drive protrusion 34e contacts the third lens frame 35 in the rotation direction (FIG. 10 (a)). More specifically, the drive protrusion 34e contacts the first sliding portion E1 in the rotation direction. When the drive frame 34 further rotates in the R2 direction, the third lens frame 35 is pushed in the rotation direction by the drive protrusion 34e, and the third lens frame 35 rotates in the R3 direction against the torque T (FIG. 10B). . When the drive frame 34 further rotates, the third lens frame 35 rotates in the R3 direction to the retracted position Q2 (FIG. 11A). When the third lens frame 35 is guided from the insertion position Q1 to the retracted position Q2, the drive protrusion 34e slides with the first sliding portion E1.

When the drive frame 34 rotates to the retract completion position P2, the third lens frame 35 is held at the retract position Q2 (FIG. 11A). When viewed from the Y-axis direction, the second sliding portion E2 of the lens frame main body 35a is curved along the second helicoid portion 34c of the drive frame 34. For this reason, from the middle of the retract drive range C2 to the retract completion position P2, the drive protrusion 34e slides with the second sliding portion E2, and the third lens frame 35 is held at the retract position Q2.
At the retracted position Q2, the third lens frame 35 is disposed on the outer side in the radial direction of the drive frame 34. Specifically, the drive protrusion 34e of the drive frame 34 is in contact with the sliding portion 35b of the third lens frame 35 in the radial direction. When viewed from the Y axis direction positive side, a gap H2 corresponding to the protruding amount of the drive protrusion 34e in the radial direction is secured between the second helicoid portion 34c of the drive frame 34 and the third lens frame 35. (FIG. 5). Thereby, even if the drive frame 34 moves to the Y axis direction negative side with respect to the third lens frame 35 in a state where the third lens frame 35 is disposed at the retracted position Q2, the drive frame 34 is not moved to the third lens frame. 35 does not interfere.

While the drive frame 34 is rotationally driven to the retreat completion position P2, the control unit main body 16 monitors whether or not the third lens frame 35 is disposed at the retreat position Q2. Specifically, based on the detection signal from the retraction sensor 38, the control unit main body 16 determines whether or not the third lens frame 35 is disposed at the retraction position Q2 (S3).
When it is determined by the control unit main body 16 that the third lens frame 35 is disposed at the retracted position Q2, the drive frame 34 is further rotated in the R2 direction to the retracted position P1 by the zoom motor 32 (S4).
In the collapsing operation range C1, the drive frame 34 moves in the Y axis direction negative side (direction approaching the fixed frame 33) while rotating in the R2 direction with respect to the fixed frame 33. For this reason, as shown in FIG. 12, when the drive frame 34 rotates in the R2 direction from the retreat completion position P2, the portion of the drive frame 34 that comes into contact with the third lens frame 35 includes the drive protrusion 34e and the second helicoid portion 34c. Then, it finally moves to the drive frame main body 34a (FIGS. 12A to 12C).

Torque T is applied to the third lens frame 35 by a spring 37. For this reason, the third lens frame 35 rotates in the R4 direction while sliding with the drive protrusion 34e, the second helicoid portion 34c, and the radially outer portion of the drive frame main body 34a (FIG. 11B, FIG. 12). b)). At this time, the third sliding portion E3 slides in the rotational direction and the Y-axis direction with the driving protrusion 34e, the second helicoid portion 34c, and the radially outer portion of the driving frame main body 34a.
When the drive frame 34 rotates to the retracted position P1, the rotation of the drive frame 34 stops. At this time, as shown in FIGS. 14A and 14B, the drive protrusion 34 e is accommodated in the accommodation groove 31 c formed in the master flange 31. Thereby, the axial direction dimension of the lens barrel 3 in the retracted state can be shortened.
On the other hand, when the control unit main body 16 determines that the third lens frame 35 is not disposed at the retracted position Q2, the third lens frame 35 is not normally driven to the retracted position Q2 by the drive frame 34. When the drive frame 34 is further rotationally driven in the R2 direction in this state, the drive frame 34 moves to the Y axis direction negative side while rotating and collides with the third lens frame 35. In this case, in order to normally drive the third lens frame 35 to the retracted position Q2, for example, the positions of the third lens frame 35 and the drive frame 34 are initialized. Specifically, the third lens frame 35 is driven to the Y axis direction negative side by the focus motor 36 to the second position U2 (S5). With the third lens frame 35 disposed at the second position U2, the drive frame 34 is rotationally driven in the R1 direction by the zoom motor 32 to the wide angle position P3 (S6). With the drive frame 34 in the wide-angle position P3, the third lens frame 35 is driven to the Y axis direction positive side to the first position U1 (S7). Thereafter, the above-described operation is repeated from step S2 until the third lens frame 35 is normally driven to the retracted position Q2.

(4.3: Operation when the power is turned on)
When the power switch 6 is switched from OFF to ON, power is supplied to each part, and the drive frame 34 is rotationally driven by the zoom motor 32. Specifically, in the retraction operation range C1, the drive frame 34 is driven in the R1 direction, and the drive frame 34 rotates while moving to the Y axis direction positive side with respect to the fixed frame 33. The drive frame 34 moves to the Y axis direction positive side while sliding with the third lens frame 35. A tapered surface 35 e is formed on the lens frame main body 35 a of the third lens frame 35. Therefore, as shown in FIGS. 12A to 12C, the third lens frame 35 can be prevented from being caught by the second helicoid portion 34c and the drive protrusion 34e of the drive frame 34 by the tapered surface 35e. The third lens frame 35 gets over the second helicoid portion 34c and the drive protrusion 34e along the tapered surface 35e. Accordingly, the third lens frame 35 rotates in the R3 direction to the retracted position Q2.

From the retreat completion position P2, the drive frame 34 is further rotationally driven in the R1 direction. In the retreat drive range C2, the drive frame 34 rotates without moving in the Y axis direction with respect to the fixed frame 33. Therefore, the drive frame 34 rotates in the R1 direction in a state where the sliding portion 35b is in contact with the drive protrusion 34e in the radial direction. As a result, the drive frame 34 and the third lens frame 35 rotate as shown in FIGS. 11 (a), 10 (b), and 10 (c). The drive frame 34 stops at the wide angle position P3. With these operations, the digital camera 1 enters a shooting state.
〔effect〕
The effects obtained by the digital camera 1 and the lens barrel 3 are as follows.
(1)
In the lens barrel 3, when the drive frame 34 rotates with respect to the master flange 31, the drive protrusion 34e of the drive frame 34 contacts the third lens frame 35, and the third lens frame 35 moves from the insertion position Q1 to the retracted position Q2. Led to. In addition, the drive frame 34 moves in the Y-axis direction with respect to the master flange 31 in a state where the third lens frame 35 is disposed at the retracted position Q2. For this reason, it is not necessary to provide an accommodation space for the third lens frame 35 in the retracted state inside the drive frame 34 in the radial direction. Thereby, the dimension of the master flange 31 or the drive frame 34 in the Y-axis direction can be shortened. That is, the lens barrel 3 can be downsized.

(2)
In the lens barrel 3, the third lens frame 35 is guided from the insertion position Q1 to the retracted position Q2 by the drive frame 34 in the retract drive range C2, and the third lens frame 35 is retracted by the drive frame 34 in the retracting operation range C1. Held at Q2. That is, the third lens frame 35 can be rotationally driven using the rotational movement of the drive frame 34, and the third lens frame 35 can be held at the retracted position Q2 using the linear movement of the drive frame 34.
As described above, since the third lens frame 35 can be rotationally driven and held at the retracted position Q2 by using the operation of the drive frame 34, it is necessary to provide a drive unit for retracting the third lens frame 35. There is no. Thereby, the structure which the 3rd lens frame 35 retracts | saves with a simple structure is realizable.

(3)
In the lens barrel 3, the third lens frame 35 is given a torque T in the R4 direction by a spring 37. Therefore, for example, when the third lens frame 35 is rotationally driven by the drive protrusion 34e of the drive frame 34, the position of the third lens frame 35 is stabilized.
Further, for example, in the collapsing operation range C <b> 1, the third lens frame 35 is pressed against the radially outer portion of the drive frame 34. As a result, the position of the third lens frame 35 in the retracting operation range C1 is stabilized.
Further, for example, at the insertion position Q1, the third lens frame 35 is pressed against the stopper 31b. Thereby, the position of the third lens frame 35 in the photographing state is stabilized.
(4)
In the lens barrel 3, a retract drive range C2 in which the drive protrusion 34e can come into contact with the third lens frame 35 and a zoom operation range C3 in which the drive protrusion 34e cannot come into contact with the third lens frame 35 are provided. ing. For this reason, even if the drive frame 34 rotates in the zoom operation range C3, the drive protrusion 34e does not interfere with the third lens frame 35. Thereby, the entire operable range of the third lens frame 35 in the Y-axis direction can be used as the use range U, and a large focus adjustment range can be secured. In addition, since it is not necessary to secure an extra operating range of the third lens frame 35, the lens barrel 3 can be reduced in size.

(5)
In the lens barrel 3, the sliding portion 35 b of the third lens frame 35 has a second sliding portion E 2 that is curved along the radially outer portion of the drive frame 34. For this reason, the focus lens L3 can be disposed close to the drive frame 34 at the retracted position Q2. Thereby, the range in which the third lens frame 35 protrudes radially outward from the drive frame 34 can be reduced, and the lens barrel 3 in the direction perpendicular to the Y-axis direction (for example, the X-axis direction in FIG. 5). Dimensions can be shortened.
Further, the third lens frame 35 is held at the retracted position Q2 by the second sliding portion E2 of the sliding portion 35b even if the drive frame 34 rotates in the retract driving range C2. Therefore, for example, as shown in FIG. 5, it is possible to prevent the third lens frame 35 from further rotating in the R3 direction from the retracted position Q2. Thereby, the operation range of the third lens frame 35 can be minimized, and the size of the lens barrel 3 in the direction perpendicular to the Y-axis direction (for example, the X-axis direction in FIG. 5) can be shortened. .

Further, even if the drive frame 34 rotates and moves to the Y axis direction negative side in the retracting operation range C1, the third lens frame 35 is held at the retracted position Q2 by the third sliding portion E3 of the sliding portion 35b. The Thereby, the drive frame 34 can be prevented from interfering with the third lens frame 35 in the Y-axis direction, and the smooth operation of the drive frame 34 and the third lens frame 35 can be realized.
(6)
In the lens barrel 3, since the second sliding portion E2 is secured in the sliding portion 35b, the retracting operation of the driving frame 34 is started in a state where the driving projection 34e is separated from the rotation axis B. For this reason, the drive protrusion 34e slides in the Y-axis direction with the sliding portion 35b in a state where the load F acting on the third lens frame 35 from the drive frame 34 is small. That is, since the second sliding portion E2 is secured, the frictional resistance between the sliding portion 35b and the drive protrusion 34e is reduced. Thereby, the smooth operation of the drive frame 34 and the third lens frame 35 can be realized in the retracting operation range C1.

(7)
In the lens barrel 3, the third lens frame 35 is accommodated in the accommodating portion 33f of the fixed frame 33 at the retracted position Q2. Thereby, it is possible to prevent dust and the like from adhering to the focus lens L3 at the retracted position Q2, and to prevent deterioration of the optical performance of the imaging optical system O.
(8)
In the lens barrel 3, the drive protrusion 34 e is accommodated in the accommodation groove 31 c of the master flange 31 at the retracted position P1. For this reason, the lens barrel 3 can be further reduced in size.
(9)
In the lens barrel 3, a retraction sensor 38 that detects the third lens frame 35 is provided. For this reason, it is possible to detect a malfunction of the third lens frame 35 and to prevent the drive frame 34 from colliding with the third lens frame 35 in the Y-axis direction. That is, the third lens frame 35 and the drive frame 34 can be prevented from being damaged.

(10)
In the lens barrel 3, the third lens group G3 is a lens group for focus adjustment. The lens group for focus adjustment tends to have a smaller outer diameter and a smaller number of lenses constituting the lens group than the other lens groups. For this reason, compared with other lens groups, the structure which retracts a lens group to the radial direction outer side of the drive frame 34 is easily realizable.
(11)
In the lens barrel 3, a spring 37 included in a mechanism for adjusting the focus is used as an elastic member that generates a torque T to the third lens frame 35. For this reason, it is not necessary to newly provide an elastic member such as a spring in order to apply the torque T to the third lens frame 35, and the structure can be simplified.

(12)
As described above, with the downsizing of the lens barrel 3, the digital camera 1 can be downsized. In particular, since the dimension of the lens barrel 3 in the Y-axis direction is shortened, the digital camera 1 can be thinned.
Second Embodiment
[1. Constitution〕
In the first embodiment described above, the operation range of the drive frame 34 in the rotation direction has the collapsible operation range C1, the retreat drive range C2, and the zoom operation range C3. However, the operation range of the drive frame 34 is not limited to these configurations. For example, the retreat drive range C2 and the zoom operation range C3 may be one rotation operation range.

  Specifically, as shown in FIG. 15, in the lens barrel according to the second embodiment, for example, the operating range of the drive frame 34 is configured by a collapsible operating range C11 and a zoom operating range C12. Compared to the first embodiment described above, the retract drive range C2 is included in the zoom operation range C12, and the retract drive range C2 is omitted. Therefore, in the retracting operation range C11, the drive frame 34 moves in the Y axis direction while rotating with respect to the fixed frame 33, and in the zoom operation range C12, the drive frame 34 moves in the Y axis direction with respect to the fixed frame 33. Rotate without doing. Similar to the zoom operation range C3, the zoom operation range C12 is used to adjust the zoom magnification. The zoom operation range C12 is a rotation operation range between the wide-angle position P12 and the telephoto position P13. For example, the wide angle position P12 of the zoom operation range C12 corresponds to the retreat completion position P2 of the first embodiment. The telephoto position P13 in the zoom operation range C12 corresponds to the wide-angle position P3 in the first embodiment.

In this case, since the drive protrusion 34e interferes with the third lens frame 35 in the zoom operation range C12, the focus cannot be adjusted while adjusting the zoom magnification. For this reason, as shown in FIG. 16, the operation range of the third lens frame 35 in the Y-axis direction is composed of a first operation range U14 and a second operation range V15.
The first operation range U14 is an operation range between the first position U11 and the second position U12, and is used when the third lens frame 35 is retracted. For this reason, the first operation range U14 includes a range in which the third lens frame 35 can come into contact with the drive protrusion 34e.
The second operation range U15 is an operation range between the second position U12 and the third position U13, and is used for focus adjustment. For this reason, in the second operation range U15, the third lens frame 35 is disposed on the Y axis direction negative side with respect to the drive protrusion 34e, and the third lens frame 35 cannot contact the drive protrusion 34e.

When the drive frame 34 is disposed in the retracting operation range C11, the control unit 10 restricts the operation range of the third lens frame 35 by the focus motor 36 within the first operation range U14. More specifically, in this case, the third lens frame 35 is held at the first position U11 by the focus motor 36. On the other hand, when the drive frame 34 is disposed in the zoom operation range C12, the control unit 10 restricts the operation range of the third lens frame 35 by the focus motor 36 within the second operation range U15.
[2. Operation)
The operation of the lens barrel according to the second embodiment will be described with reference to FIG. FIG. 17 is an operation flowchart of the lens barrel according to the second embodiment.
(2.1: Operation in shooting state)
In the case of the present embodiment, there is a possibility that the drive protrusion 34e contacts the third lens frame 35 in the zoom operation range C12. For this reason, when the drive frame 34 is disposed in the zoom operation range C12, the operation range of the third lens frame 35 is limited by the control unit 10 within the second operation range U15. Accordingly, it is possible to prevent the drive protrusion 34e from interfering with the third lens frame 35 when adjusting the zoom magnification.

(2.2: Operation when power is off)
In the present embodiment, the telephoto position P13 corresponds to a position where the driving of the third lens frame 35 is started. Therefore, the drive frame 34 is rotationally driven in the R1 direction to the telephoto position P13 (S101). Next, the third lens frame 35 is driven to the first position U11 by the focus motor 36 (S102). When the driving of the third lens frame 35 and the drive frame 34 is completed, the drive frame 34 is rotationally driven in the R2 direction by the zoom motor 32 to the wide-angle position P12 (retraction completion position) (S103). As a result, the third lens frame 35 contacts the drive protrusion 34e in the rotation direction, and the third lens frame 35 is rotationally driven by the drive frame 34 to the retracted position Q2.
As in the first embodiment, while the drive frame 34 is rotationally driven to the wide angle position P12, the control unit main body 16 monitors whether or not the third lens frame 35 is disposed at the retracted position Q2. Specifically, based on the detection signal from the retract sensor 38, the control unit main body 16 determines whether or not the third lens frame 35 is disposed at the retract position Q2 (S104).

When it is determined by the control unit main body 16 that the third lens frame 35 is disposed at the retracted position Q2, the drive frame 34 is further rotationally driven in the R2 direction by the zoom motor 32 to the retracted position P11 (S105).
On the other hand, when the control unit main body 16 determines that the third lens frame 35 is not disposed at the retracted position Q2, the third lens frame 35 is not normally driven to the retracted position Q2 by the drive frame 34. In this case, in order to normally drive the third lens frame 35 to the retracted position Q2, the positions of the third lens frame 35 and the drive frame 34 are initialized as in the first embodiment. Specifically, the third lens frame 35 is driven to the Y-axis direction negative side by the focus motor 36 to the second position U12 (S106). With the third lens frame 35 disposed at the second position U2, the zoom motor 32 rotates the drive frame 34 to the telephoto position P13 in the R1 direction (S107). With the drive frame 34 in the telephoto position P13, the third lens frame 35 is driven to the Y axis direction positive side to the first position U11 (S108). Thereafter, the above-described operation is repeated from step S103 until the third lens frame 35 is normally driven to the retracted position Q2.

(2.3: Operation when the power is turned on)
When the power switch 6 is switched from OFF to ON, power is supplied to each part, and the drive frame 34 is rotationally driven by the zoom motor 32. In the present embodiment, the drive frame 34 is rotationally driven in the R1 direction by the zoom motor 32 to the telephoto position P13. At that time, the third lens frame 35 rotates in the R4 direction from the retracted position Q2 to the insertion position Q1. When the drive frame 34 rotates to the telephoto position P13, the focus lens 36 drives the third lens frame 35 to the second position U12 on the Y axis direction negative side. With these operations, the digital camera 1 enters a shooting state.
[3. effect〕
As described above, in the lens barrel according to the second embodiment, the retraction drive range C2 is omitted, and thus the rotation angle of the drive frame 34 is smaller than that in the first embodiment. For this reason, it is not necessary to rotate the drive frame 34 in order to retract the third lens frame 35. Thereby, the time for the collapsing operation can be shortened and the power consumption is reduced.

Further, when the drive frame 34 is disposed in the zoom operation range C12, the operation range of the third lens frame 35 is limited by the control unit 10 within the second operation range U15. Accordingly, it is possible to prevent the drive protrusion 34e from interfering with the third lens frame 35 when adjusting the zoom magnification.
<Other embodiments>
The specific configuration of the present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the invention.
(1)
In the first embodiment described above, when the third lens frame 35 is retracted, the drive frame 34 is rotationally driven in the R2 direction to the retract completion position P2. However, the position of the retract completion position P2 is not limited to the first embodiment. For example, as shown in FIG. 18, the position of the drive protrusion 34e when the third lens frame 35 reaches the retreat position Q2 is set to the retreat completion position P22. At this time, the sliding portion 35b of the third lens frame 35 is omitted from the second sliding portion E2, and the first sliding portion E11 corresponding to the first sliding portion E1 and the third sliding portion. And a second sliding portion E12 corresponding to the portion E3.

In this case, the rotation angle of the drive frame 34 can be made smaller than in the first embodiment. Thereby, the time for the collapsing operation can be shortened and the power consumption is reduced.
(2)
The shape of the third lens frame 35 is not limited to the shape described above. For example, as long as it has a portion corresponding to the sliding portion 35b, the lens frame main body 35a may not be plate-shaped.
Further, even when the sliding portion 35b does not have the second sliding portion E2 and the third sliding portion E3, a configuration in which the third lens frame 35 is retracted to the retracted position Q2 can be realized. For example, as shown in FIG. 19, the sliding portion 235b of the third lens frame 235 has only the first sliding portion E21 corresponding to the first sliding portion E1, and the lens frame main body 235a is entirely formed. When bent, or as shown in FIG. 20, the sliding part 335b of the third lens frame 335 has only the first sliding part E31 corresponding to the first sliding part E1, and the lens frame. The case where the main body 335a is entirely linear may be considered. Even in these cases, the lens barrel 3 can be downsized.

(3)
The arrangement and shape of the drive protrusion 34e are not limited to the above-described embodiment. For example, in the above-described embodiment, the drive protrusion 34e protrudes outward in the radial direction from the second helicoid portion 34c. However, the positional relationship between the drive protrusion 34e and the second helicoid portion 34c is not limited to the above-described embodiment. For example, like the drive frame 134 shown in FIG. 21, an embodiment in which the drive protrusion 134e does not protrude radially outward from the second helicoid part 134c is also conceivable. In this case, the radially outer surface 134f of the drive protrusion 134e substantially coincides with the radially outer surface 134g of the second helicoid portion 134c. Thereby, when the drive frame 34 moves in the Y-axis direction with respect to the third lens frame 35, the frictional resistance generated between the third lens frame 35 and the drive frame 34 can be reduced.

For example, like the drive frame 234 shown in FIG. 22, the drive protrusion 234e may be a plate-like part long in the rotation direction. The drive protrusion 234e extends in the rotational direction along the second helicoid portion 234c. Thus, for example, as shown in FIGS. 19 and 20, even if the sliding portions 235b and 335b are linear, the third lens frames 235 and 335 are moved in the R3 direction along with the rotation of the drive frame 34. An operating range that does not rotate in the R4 direction can be secured. This makes it easier to hold the third lens frame 35 at the retracted position Q2, and prevents the drive frame 34 from colliding with the third lens frame 35 in the Y-axis direction when the drive frame 34 is retracted.
(4)
In the above-described embodiment, the torque T is applied to the third lens frame 35 by the spring 37. However, the configuration for applying torque to the third lens frame 35 is not limited to the above-described embodiment. For example, the third lens frame 35 and the master flange 31 may be elastically connected by a spring different from the spring 37.

In the above-described embodiment, the direction of the torque T applied to the third lens frame 35 is clockwise when viewed from the Y axis direction positive side. However, for example, the direction of the torque T may be counterclockwise. In this case, by providing a mechanism for holding the third lens frame 35 at the insertion position Q1, a mechanism for positioning the third lens frame 35 at the retracted position Q2, etc., the third lens frame is driven by the drive protrusion 34e. 35 is guided from the insertion position Q1 to the retracted position Q2.
Furthermore, in the above-described embodiment, the spring 37 presses the third lens frame 35 to the Y axis direction positive side, but the spring 37 may press the third lens frame 35 to the Y axis direction negative side. .
(5)
The retraction sensor 38 is not limited to the above-described embodiment. For example, as long as the sensor can detect whether or not the third lens frame 35 is disposed at the retreat position Q2, the retraction sensor 38 may be a non-contact proximity sensor or the like, or a contact sensor. Also good. Further, the attachment position is not limited to the accommodating portion 33f.

Further, the operation of the lens barrel 3 using the retraction sensor 38 is not limited to the above-described operation. For example, in the case of the first embodiment, the order of steps S5 and S6 may be switched, and steps S5 and S6 may be started simultaneously. In the case of the second embodiment, the order of steps S106 and S107 may be switched, and steps S106 and S107 may be started simultaneously.
(6)
In the above-described embodiment, the third lens frame 35 is provided with the tapered surface 35e in order to facilitate the operation of the drive frame 34 and the third lens frame 35 in the retracting operation range C11. However, for example, the drive frame 34 may be provided with a tapered surface or a portion for guiding the third lens frame 35.

(7)
In the above-described embodiment, the imaging optical system O is taken as an example of the optical system, and the focus lens L3 is taken as an example of the optical element. However, the optical system and the optical element are not limited to the above-described embodiments. For example, the optical system only needs to include at least one optical element. The optical element may be an optical component made of an optical material. Examples of the optical element include a prism, a mirror, and a filter in addition to the lens.
(8)
The configurations of the digital camera 1 and the lens barrel 3 are not limited to the above-described embodiment. For example, the drive source of the drive frame 34 may be configured so that the photographer manually applies a drive force to the drive frame 34 in addition to the zoom motor 32. Further, the configuration of the imaging optical system O is not limited to the above-described embodiment. Other optical systems may be used as long as at least one optical element is included.

(9)
The configuration of the above-described embodiment can be combined in various patterns.

  The lens barrel and camera according to the present invention can be downsized. For this reason, it is useful in the field | area in which size reduction of the apparatus carrying an optical system is calculated | required.

Schematic perspective view of digital camera Schematic perspective view of digital camera Disassembled perspective view of lens barrel Schematic plan view of lens barrel The figure which shows the operation range of the drive frame 34 and a 3rd lens frame Plan view of the third lens frame The figure which shows the operating range of the 3rd lens frame in a Y-axis direction Detailed view around the spring Block diagram of control unit Operation explanatory diagram of drive frame and third lens frame Operation explanatory diagram of drive frame and third lens frame The figure which shows the positional relationship of the Y-axis direction of a drive frame and a 3rd lens frame. Lens barrel operation flow diagram when the power switch is switched from ON to OFF The figure which shows the positional relationship of a drive protrusion and an accommodation groove | channel The figure which shows the operation range of the drive frame 34 and a 3rd lens frame (2nd Embodiment). The figure which shows the operation range of the 3rd lens frame in a Y-axis direction (2nd Embodiment). Operation flow diagram of lens barrel according to the second embodiment The figure which shows the operating range of the drive frame 34 and a 3rd lens frame (other embodiment). The figure which shows the modification of a 3rd lens frame (other embodiment). The figure which shows the modification of a 3rd lens frame (other embodiment). The figure which shows the modification of a drive protrusion (other embodiment). The figure which shows the modification of a drive protrusion (other embodiment).

Explanation of symbols

1 Digital camera (camera)
2 Exterior 3 Lens barrel (barrel)
4 Release button 5 Operation dial 6 Power switch 7 Zoom adjustment lever 8 LCD monitor 9 Image recording unit 10 Control unit 31 Master flange (fixing member)
31a Shaft 31b Stopper 31c Housing groove (concave)
32 Zoom motor (first actuator)
33 Fixed frame (fixing member)
34 Drive frame (rotating member)
34e Driving projection 35 Third lens frame (retraction frame)
35a Lens frame body 35b Sliding part 35c Bearing part 36 Focus motor (second actuator)
37 Spring (elastic member)
38 Retraction sensor 39 CCD (imaging part)
A Optical axis B Rotating axis C1 Retraction operation range C2 Retraction drive range (first rotation operation range)
C3 Zoom operation range (second rotation operation range)
E1 First sliding portion E2 Second sliding portion E3 Third sliding portion L3 Focus lens (optical element)
U Use range U1 1st position U2 2nd position P1 Retraction position P2 Retraction completion position P3 Wide angle position P4 Telephoto position Q1 Insertion position Q2 Retraction position

Claims (12)

A lens barrel for supporting the optical system,
A fixing member;
An annular rotating member supported by the fixing member so as to be rotatable around a first rotation axis with respect to the fixing member;
A member provided with an optical element included in the optical system, wherein the second rotation shaft is supported by the fixing member so as to be rotatable with respect to the fixing member, and is arranged on the radially outer side of the rotating member. A retraction frame having
The retracting frame serves as the fixed member between an insertion position where the optical element is inserted into an effective optical path of the optical system and a retracted position where the retracting frame is disposed radially outside the rotating member. Is rotatable with respect to
The rotating member has an abutting portion capable of abutting on the retraction frame in a rotating direction of the rotating member, and the abutting portion guides the retraction frame from the insertion position to the retraction position. Moving in a direction along the first rotation axis while rotating with respect to the fixed member in a state of being arranged at the retracted position;
The lens barrel. The range of operation of the rotating member in the rotational direction relative to the fixed member is a collapsing operation in which the rotating member rotates about the first rotational axis while moving in the direction along the first rotational axis with respect to the fixed member. A rotation operation range in which the rotating member rotates around the first rotation axis without moving in the direction along the first rotation axis with respect to the fixed member;
In the rotational operation range, the retracting frame is guided from the insertion position to the retracted position by the rotating member,
In the retracting operation range, the retracting frame is held radially outward of the rotating member by the rotating member.
The lens barrel according to claim 1. An elastic member that applies torque to the retraction frame so as to rotate from the retraction position to the insertion position;
In the retracting operation range, the retracting frame is pressed against the radially outer portion of the rotating member by the torque from the elastic member.
The lens barrel according to claim 2. The fixing member has a stopper with which the retraction frame abuts in the rotation direction at the insertion position.
The lens barrel according to claim 3. The rotation operation range includes a first rotation operation range in which the contact portion can contact the retraction frame in the rotation direction, and a second rotation in which the contact portion cannot contact the retraction frame in the rotation direction. An operating range;
The lens barrel according to claim 4. The retraction frame includes a bearing portion that is disposed on the outer side in the radial direction of the rotation member and is rotatably supported by the fixing member, and a retraction frame body that is fixed to the bearing portion and provided with the optical element. And
When viewed from the direction along the first rotation axis, the retracting frame main body is disposed radially outward of the rotating member in a state where the retracting frame main body is in contact with the contact portion in the radial direction of the rotating member. Arranged,
The lens barrel according to claim 5. The retractable frame body has a sliding portion that contacts or slides with the contact portion,
When viewed from a direction along the first rotation axis, the sliding portion is curved along a radially outer portion of the rotating member in a state where the retracting frame main body is located at the retracted position.
The lens barrel according to claim 6. The fixing member has an accommodating portion in which the retracting frame is accommodated in the retracted position.
The lens barrel according to claim 7. The contact portion is a protrusion extending in a direction along the first rotation axis,
The fixing member has a recess in which the contact portion is accommodated in a state in which the rotating member approaches the fixing member.
The lens barrel according to claim 8. A first actuator provided on the fixed member and rotationally driving the rotating member;
A retraction sensor for detecting whether or not the retraction frame is disposed at the retraction position;
A controller that controls the operation of the first actuator based on a detection result from the retraction sensor;
The control unit restricts movement of the rotating member in a direction along the first rotation axis based on a detection result that the retracting frame is not disposed at the retracted position.
The lens barrel according to claim 9. An operation controlled by the control unit, further comprising a second actuator for driving the retraction frame in a direction along the first rotation axis;
The operation range of the retraction frame in the direction along the first rotation axis with respect to the fixing member is a first operation range in which the retraction frame can contact the contact portion in the rotation direction, and the retraction frame includes the A second operating range incapable of contacting the contact portion in the rotation direction,
When the rotating member is disposed within the retracting operation range, the control unit limits the operating range of the retracting frame by the second actuator to the first operating range, and the rotating member is within the rotating operation range. The control unit restricts the operation range of the retraction frame by the second actuator to be within the second operation range.
The lens barrel according to claim 10. The lens barrel according to any one of claims 1 to 11,
The optical system held by the lens barrel;
An imaging unit that captures an optical image of a subject formed by the optical system;
An exterior portion for holding the lens barrel;
With a camera.

Images