JP6271993B2 - Optical equipment - Google Patents

Description

  The present invention relates to an optical apparatus that holds a lens movably.

  As a lens barrel of an imaging device such as a digital camera, a lens barrel having a zoom mechanism for moving a lens to a predetermined position by moving a plurality of lens holding portions that hold a plurality of lenses in the optical axis direction by rotation of a cam barrel It has been proposed (Patent Document 1). In this proposal, cam grooves are respectively formed in the inner peripheral portion and the outer peripheral portion of the cam cylinder. The first lens group holding portion is assembled to the outer peripheral portion of the cam cylinder with the phase shifted from the subject side, so that it does not fall off during normal operation.

  Further, as a technique for restricting the rotation of the zoom operation cylinder when the camera is carried, a technique in which a lock part is provided on the outer peripheral side of the zoom operation cylinder has been proposed (Patent Document 2). According to this proposal, the lock by the lock component is released when a rotational force exceeding a specified value is applied to the zoom operation cylinder at the time of locking.

JP 2010-156870 A JP 2007-33504 A

  Incidentally, in recent years, an imaging apparatus such as a digital camera has been reduced in size, while a higher zoom magnification of a lens barrel is required. For this reason, even in such a lens barrel, it is necessary to improve the strength against a twisting force caused by an external impact or a user's erroneous operation.

  However, in Patent Document 1, when the user forcibly rotates the first group lens holding unit by mistake, the first group lens holding unit is deformed or the like and rotated to the cam cylinder built-in phase, and is dropped from the cam tube. There is a risk that.

  Moreover, in the said patent document 2, the locking components provided in the outer peripheral side of a zoom operation cylinder are needed separately, and it is necessary to also perform a locking operation manually.

  Accordingly, an object of the present invention is to easily determine the mechanical end on the feeding side without separately providing a dedicated locking component and to improve the strength against external impact and twisting force.

In order to achieve the above object, an optical apparatus of the present invention includes a fixed cam ring and a moving cam ring that moves in the optical axis direction while rotating following a cam groove formed in an inner peripheral portion of the fixed cam ring. An inner lens holding portion that moves in the optical axis direction following the cam groove formed in the inner peripheral portion of the moving cam ring, and a light that follows the cam groove formed in the outer peripheral portion of the moving cam ring. An outer lens holding portion that moves in the axial direction and an outer peripheral side of the outer lens holding portion is provided between the fixed cam ring, fixed to the moving cam ring, and rotated integrally with the moving cam ring. An outer cylinder that moves in the axial direction, and the outer locus of the outer lens holding portion is formed on the inner circumference of the outer cylinder and has the same locus as the cam groove formed on the outer circumference of the movable cam ring. projections to be inserted in a curved shape of the inner peripheral groove is provided with, on the outer cylinder, the front A linear insertion groove extending from the opening formed on the image plane side end of the peripheral wall of the outer cylinder toward the subject side along the optical axis direction is formed, and the protrusion is inserted from the opening in the optical axis direction. Thus, the outer lens holding portion is structured to be incorporated in the outer cylinder, and an end portion on the feeding side of the inner circumferential groove includes an end portion on the feeding side and an end portion on the subject side of the insertion groove. The connection portion is provided with a rotation restricting portion on which the protrusion can abut in the circumferential direction .

  According to the present invention, the mechanical end on the feeding side can be easily determined without separately providing a dedicated lock component, and the strength against an external impact or twisting force can be improved.

(A) is the perspective view which looked at the digital camera which is an example of embodiment of an imaging device provided with the lens barrel of this invention from the front side, (b) is the figure which looked at the digital camera shown to (a) from the back side It is. It is a control block diagram of a digital camera. It is sectional drawing in alignment with the optical axis direction in the accommodation state of a lens-barrel. It is sectional drawing in alignment with the optical axis direction in the imaging | photography state (drawing-out state) of a lens-barrel. It is a disassembled perspective view of a lens barrel. It is a perspective view of a lens barrel. It is sectional drawing which follows the radial direction of a lens-barrel. (A) is an exploded perspective view of the outer cylinder, the fifth group lens holding portion, and the movable cam ring, and (b) is a perspective view of the outer cylinder as viewed from the image plane side.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1A is a perspective view of a digital camera, which is an example of an embodiment of an imaging apparatus including a lens barrel, which is an example of an optical apparatus embodying the present invention, as viewed from the front side, and FIG. It is the figure which looked at the digital camera shown to (a) from the back side.

  As shown in FIG. 1A, a digital camera 23 according to this embodiment includes a finder 21 for determining the composition of a subject, an auxiliary light source 20 for performing photometric distance measurement, a strobe device 22, and a lens barrel on the front side. 16 is provided. The lens barrel 16 is of a zoom type in which the zoom magnification is changed by moving in the optical axis direction between the photographing position and the storage position.

  On the upper surface side of the digital camera 23, a release button 17, a power switch button 19, and a zoom switch 18 are provided. As shown in FIG. 1B, operation buttons 26 to 31, a display 25 such as an LCD, and a viewfinder eyepiece 24 are provided on the back side of the digital camera 23.

  FIG. 2 is a control block diagram of the digital camera 23 of the present embodiment. The bus 43 includes a CPU 45, ROM 44, RAM 46, release button 17, operation buttons 26 to 31, display 25, power switch button 19, zoom switch 18, memory 39, compression / decompression unit 40, memory card drive 41, and drive circuit 42. Connected.

  Connected to the drive circuit 42 are a zoom mechanism 32 for zooming the lens barrel 16, a focus drive mechanism 7 for driving the focus lens 6a, a shutter drive mechanism 33 for driving the shutter 2, and an aperture drive mechanism 35 for driving the diaphragm 34. Is done. In addition, the imaging circuit 10 such as a CCD sensor or a CMOS sensor and the strobe device 22 are connected to the drive circuit 42. Each unit connected to the drive circuit 42 is controlled to be driven via the drive circuit 42 based on a signal from the CPU 45.

  The ROM 44 stores various control programs and the like, and the RAM 46 stores data necessary for the various control programs. The analog signal processing unit 36 performs analog processing on the image data output from the image sensor 10 and outputs the processed image data to the A / D conversion unit 37.

  The A / D conversion unit 37 converts analog data captured from the image sensor 10 into digital data and outputs the digital data to the digital signal processing unit 38. The digital signal processing unit 38 performs a predetermined process on the digital data converted by the A / D conversion unit 37 and outputs it to the memory 39 as image data.

  The image data stored in the memory 39 is subjected to compression processing such as JPEG and TIFF by the compression / decompression unit 40, and then output to and stored in a memory card attached to the memory card drive 41.

  Further, the image data stored in the memory 39 and the image data stored in the memory card drive 41 can be expanded by the compression / decompression unit 40 and then displayed on the display 25 via the bus 43. If the user views the image displayed on the display 25 and determines that the image is unnecessary, it can be erased by operating the operation button 31.

  Next, the lens barrel 16 will be described in detail with reference to FIGS.

  FIG. 3 is a cross-sectional view taken along the optical axis direction when the lens barrel 16 is housed. FIG. 4 is a cross-sectional view along the optical axis direction of the lens barrel 16 in the photographing state (the extended state). FIG. 5 is an exploded perspective view of the lens barrel 16.

  As shown in FIGS. 3 to 5, the lens barrel 16 includes a second group lens holding portion 1 that holds the second group lens 1b. A third group lens holding unit 13 for holding the third group lens 2 a is provided on the image plane side of the second group lens holding unit 1, and a shutter 2 is provided on the image plane side of the third group lens holding unit 13. The third group lens holding unit 13 and the shutter 2 constitute a third group lens unit 2A.

  On the image plane side of the shutter 2, a fourth group lens holding unit 3 that holds a fourth group lens 3 a that functions as an anti-vibration lens is provided, and on the image plane side of the fourth group lens holding unit 3, a focus lens 6 a is held. A focus lens holding unit 6 is provided.

  On the image plane side of the focus lens holding unit 6, a sixth group lens holding unit 4 that holds the sixth group lens 4c is provided. The focus lens holding unit 6 and the sixth group lens holding unit 4 constitute a focus unit. Yes. A focus motor 7 is fixed to the sixth group lens holding unit 4, and the focus lens holding unit 6 is moved in the optical axis direction by driving the focus motor 7 to perform a focusing operation. Further, on the image plane side of the sixth group lens holding unit 4, a sensor holding unit 11 that holds the imaging element 10 such as a CCD or a CMOS sensor is provided.

  As described above, in this embodiment, the second group lens holding unit 1, the third group lens unit 2A, the fourth group lens holding unit 3, and the sixth group lens holding unit 4 are sequentially arranged from the subject side to the image plane side. ing. Here, the second group lens holding unit 1, the third group lens unit 2A, and the fourth group lens holding unit 3 correspond to an example of the inner lens holding unit of the present invention. The second group lens holding unit 1, the third group lens unit 2A, the fourth group lens holding unit 3 and the sixth group lens holding unit 4 are respectively a first lens holding unit, a second lens holding unit, and a third lens. This corresponds to an example of a holding unit and a fourth lens holding unit.

  As shown in FIGS. 3 and 4, a moving cam ring 8 is provided on the outer peripheral side of the second group lens holding unit 1, the third group lens unit 2 </ b> A, the fourth group lens holding unit 3, and the sixth group lens holding unit 4. . Cam grooves corresponding to the second group lens holding portion 1, the third group lens unit 2 </ b> A, and the fourth group lens holding portion 3 are formed in the inner peripheral portion of the movable cam ring 8.

  The second group lens holding portion 1, the third group lens unit 2A, and the fourth group lens holding portion 3 move forward and backward in the optical axis direction by following the corresponding cam grooves formed in the inner peripheral portion of the movable cam ring 8. It can be done.

  A first group lens holding portion 5 that holds the first group lens 5 a is provided on the outer peripheral side of the moving cam ring 8. The first group lens 5a is disposed on the subject side of the second group lens 1b. The first group lens holding portion 5 can move forward and backward in the optical axis direction by following a cam groove formed in the outer peripheral portion of the movable cam ring 8. Here, the first group lens holding portion 5 corresponds to an example of the outer lens holding portion of the present invention.

  Further, a fixed cam ring 9 is provided on the outer peripheral side of the first group lens holding portion 5 on the outer peripheral side of the movable cam ring 8. The moving cam ring 8 can move forward and backward in the optical axis direction following a cam groove formed in the inner peripheral portion of the fixed cam ring 9. A driving ring 14 is provided on the outer peripheral side of the fixed cam ring 9, and the outer peripheral side of the driving ring 14 is covered and protected by the cover cylinder 12.

  As shown in FIGS. 4 and 5, the cam follower 4 b and the rectilinear key 4 a are provided on the outer peripheral portion of the sixth group lens holding portion 4 at approximately equal intervals in the circumferential direction. The cam follower 4b follows a cam groove 14a (see FIG. 4) formed in the inner peripheral portion of the drive ring 14. As a result, the drive ring 14 is rotationally driven by the zoom mechanism 32, whereby the sixth group lens holding portion 4 moves forward and backward in the optical axis direction following the cam groove 14a. At this time, the rectilinear key 4 a is engaged with a rectilinear groove formed in the inner peripheral portion of the fixed cam ring 9, thereby restricting rotation of the sixth group lens holding portion 4.

  Further, as the drive ring 14 rotates, the moving cam ring 8 also rotates and advances and retreats in the optical axis direction following the cam groove of the fixed cam ring 9. As the movable cam ring 8 rotates, the second group lens holding unit 1, the third group lens unit 2A, the fourth group lens holding unit 3, the sixth group lens holding unit 4, and the first group lens holding unit 5 are in the optical axis direction. Move forward and backward.

  As shown in FIG. 5, a rotation restricting portion 15 extending toward the subject side in parallel with the optical axis is provided on the outer peripheral portion of the sixth group lens holding portion 4. The shutter 2 of the third group lens unit 2A is integrally provided with a rotation restricting portion 2b.

  The rotation restricting portion 2b is formed in a sheath shape, and the rotation restricting portion 15 is inserted and holds the inserted rotation restricting portion 15 when the sixth group lens holding portion 4 moves forward and backward in the optical axis direction. At this time, since the rotation of the sixth group lens holding unit 4 is restricted by the fixed cam ring 9, as a result, the third group lens unit 2 </ b> A is restricted by the sixth group lens holding unit 4. Here, the rotation restricting portion 2b and the rotation restricting portion 15 correspond to an example of the first rotation restricting means of the present invention.

  A pair of the rotation restricting portion 15 and the rotation restricting portion 2b are arranged at a distance of approximately 180 ° in the circumferential direction of the lens barrel 16, respectively. The sixth group lens holding unit 4 and the third group lens unit 2 move relative to each other in the optical axis direction along different cam loci of the movable cam ring 8, and at this time, the rotation regulating unit 15 is inserted into the rotation regulated unit 2b. The state is maintained.

  On both sides in the circumferential direction of the lens barrel 16 of the rotation restricting portion 2b, rotation restricting contact portions 2c are provided. The rotation restricting contact portion 3b provided on the fourth group lens holding portion 3 is in contact with the rotation restricting contact portion 2c in the circumferential direction. Accordingly, the rotation of the fourth group lens holding unit 3 is restricted by the third group lens unit 2A. Here, the rotation restricting contact portion 2c and the rotation restricting contact portion 3b correspond to an example of a third rotation restricting means of the present invention.

  Further, a plurality of rotation restricting portions 1c extending toward the image plane side in parallel with the optical axis are provided in the outer peripheral portion of the second group lens holding portion 1 in the circumferential direction. When the second group lens holding unit 1 and the third group lens holding unit 13 move relative to each other in the optical axis direction, the rotation restricting unit 1c is inserted into the rectilinear groove 13a provided in the outer peripheral portion of the third group lens holding unit 13 in the optical axis direction. Inserted. Thereby, the rotation of the second group lens holding portion 1 is restricted by the third group lens unit 2A. Here, the rotation restricting portion 1c and the rectilinear groove 13a correspond to an example of a second rotation restricting means of the present invention.

  Further, a plurality of rotation restricting protrusions 1 a projecting radially outward are provided on the outer peripheral portion of the second group lens holding portion 1 in the circumferential direction. The rotation restricting protrusion 1a is formed with respect to the rectilinear groove 5b provided on the inner periphery of the first group lens holding portion 5 when the second group lens holding portion 1 and the first group lens holding portion 5 are relatively moved in the optical axis direction. Inserted in the radial direction. Accordingly, the rotation of the first group lens holding unit 5 is restricted by the second group lens holding unit 1. Here, the rotation restricting protrusion 1a and the rectilinear groove 5b correspond to an example of a fourth rotation restricting means of the present invention.

  FIG. 6 is a perspective view of the lens barrel 16. FIG. 7 is a cross-sectional view of the lens barrel 16 along the radial direction. FIG. 8A is an exploded perspective view of the outer cylinder 81, the first group lens holding portion 5, and the movable cam ring 8. FIG. 8B is a perspective view of the outer cylinder 81 as viewed from the image plane side.

  As shown in FIGS. 3, 4, and 6 to 8, an outer cylinder 81 is provided on the outer peripheral side of the movable cam ring 8 so as to be positioned on the outer peripheral side of the first group lens holding portion 5. As shown in FIG. 8, three cam grooves 81 b are formed at substantially equal intervals in the circumferential direction on the inner peripheral portion of the outer cylinder 81. The cam groove 81b has substantially the same locus as a cam groove formed on the outer peripheral portion of the movable cam ring 8, that is, a cam groove that follows when the first group lens holding portion 5 moves forward and backward in the optical axis direction. The cam groove 81b corresponds to an example of the inner peripheral groove of the present invention.

  Three cam projections 5c projecting radially outward are provided at substantially equal intervals in the circumferential direction on the outer peripheral portion of the end of the first group lens holding portion 5 on the image plane side. The cam protrusion 5 c is disposed on the opposite outer diameter side of the cam follower following the cam groove on the outer peripheral portion of the movable cam ring 8 of the first group lens holding portion 5, and engages with the cam groove 81 b of the outer cylinder 81. The cam follower and the cam protrusion 5c may be provided as an integral part.

  The outer cylinder 81 is fixed to the movable cam ring 8 by three snap fit portions 81 a and moves forward and backward in the optical axis direction integrally with the movable cam ring 8. Further, as shown in FIG. 8, a plurality of cam followers 8f protruding outward in the radial direction are provided at substantially equal intervals in the circumferential direction on the outer peripheral portion of the moving cam ring 8 on the image plane side. The snap fit portion 81a is exposed to the outside when the movable cam ring 8 moves to the vicinity of the end portion on the feeding side with respect to the fixed cam ring 9.

  Hereinafter, the lens barrel 16 will be described in detail according to the assembly order. First, the second group lens holding unit 1, the third group lens unit 2 </ b> A, and the fourth group lens holding unit 3 are incorporated in the inner peripheral portion of the movable cam ring 8. Next, the movable cam ring 8 is assembled from the image plane side of the fixed cam ring 9. In such an assembled state, the cam follower 8f of the movable cam ring 8 engages with a cam groove 9a (see FIG. 5) formed in the inner peripheral portion of the fixed cam ring 9.

  At this time, the fixed cam ring 9 has an insertion groove for assembly extending in the optical axis direction from the image side end toward the subject side at the extended end of the cam groove 9a in which the movable cam ring 8 further rotates from the storage end. 9e is formed. Therefore, by inserting the cam follower 8f of the moving cam ring 8 into the insertion groove 9e from the image plane side, the fixed cam ring 9 and the moving cam ring 8 can be connected to each other.

  Next, the focus unit including the 6-group lens holding unit 4, the drive ring 14, and the cover cylinder 12 are assembled, and the sensor holding unit 11 is assembled so as to cover from the back side and is covered. In this state, the light for correcting the tilt, decentering, etc. of each lens of the second group lens holding unit 1, the third group lens unit 2A, the fourth group lens holding unit 3, the focus lens holding unit 6 and the sixth group lens holding unit 4 Optical adjustment for axial alignment can be performed. Thereby, the lens barrel 16 having excellent optical sensitivity can be obtained.

  Thereafter, the movable cam ring 8 is rotated in the feeding direction to the assembling phase on the feeding side, and the first group lens holding portion 5 is assembled on the outer peripheral side of the moving cam ring 8 in this state. Then, the movable cam ring 8 is once rotated in the storing direction and moved to the mechanical end on the feeding side. In this state, the outer cylinder 81 is assembled on the outer peripheral side of the first group lens holding portion 5 and the movable cam ring 8.

  As shown in FIG. 8 (b), an insertion groove 81d for assembly connected to the circumferential end on the feeding side of the cam groove 81b is formed on the inner peripheral portion of the outer cylinder 81 from the image plane side end to the subject side. It is provided along the optical axis direction. The phase of the cam projection 5c of the first group lens holding portion 5 is adjusted with respect to the insertion groove 81d, and they are inserted in the optical axis direction toward the subject side end in the optical axis direction on the cam groove 81b side of the insertion groove 81d. I assembled it. In this state, the outer cylinder 81 and the moving cam ring 8 are connected and fixed to each other by the snap fit portion 81a.

  In this fixed state, the rotational phase of the movable cam ring 8 becomes the mechanical end on the feeding side of the lens barrel 16. At this time, the cam follower 8f of the moving cam ring 8 engages with the cam groove 9a of the fixed cam ring 9, and the moving cam ring 8 is restricted in rotation at the mechanical end on the feeding side so that the moving cam ring 8 and the fixed cam ring 9 are It does not fall out.

  The moving cam ring 8 moves in the optical axis direction while rotating following the cam groove 9 a of the fixed cam ring 9, but the cam projection 5 c of the first group lens holding portion 5 is also between the cam groove 81 b of the outer cylinder 81. In this state, the cam groove 81b is followed.

  Further, at the extended end of the lens barrel 16, as shown in FIGS. 7 and 8B, the cam projection 5c of the first group lens holding portion 5 is a connecting portion between the cam groove 81b of the outer tube 81 and the insertion groove 81d. It is possible to contact the rotation restricting portion 81c, which is a circumferential wall portion, in the circumferential direction. Thus, further rotation of the first group lens holding portion 5 in the extending direction is restricted without providing a dedicated lock component separately.

  As described above, in the present embodiment, the first group lens holding portion 5 can be held on the moving cam ring 8 so as not to drop off on the subject side without separately providing a dedicated locking component. The mechanical end on the feeding side can be easily determined. Further, even if a twisting force due to an external impact or a user's erroneous operation acts on the first group lens holding portion 5 in the dropping direction, the outer cylinder 81 integrated with the first group lens holding portion 5 and the movable cam ring 8 is formed. Since the rotation is restricted, the strength is improved, and it is difficult for dropout due to deflection.

  In particular, in the present embodiment, since a dedicated component for restricting the rotation of each lens holding portion 1 to 4 is not provided, the lens barrel 16 is configured to easily generate a bending force from the outside. Become advantageous.

  In the present embodiment, the cam projection 5 c of the first group lens holding portion 5 is always engaged with the cam groove 81 b of the outer cylinder 81 while the lens barrel 16 is being driven. For this reason, when an impact or the like is applied to the first group lens holding portion 5, the cam projection 5c can come into contact with the inner wall in the width direction of the cam groove 81b to prevent the first group lens holding portion 5 from falling off.

  The configuration of the present invention is not limited to that exemplified in the above embodiment, and the material, shape, dimensions, form, number, arrangement location, and the like can be changed as appropriate without departing from the scope of the present invention. It is.

1 2nd group lens holding part 2A 3rd group lens unit 2b Rotation restricting part 2c Rotation restricting contact part 3 4th lens holding part 3b Rotation restricting contact part 4 6th group lens holding part 5 1st group lens holding part 5c Cam projection 8 Moving cam ring 9 Fixed cam ring 15 Rotation restricting portion 81 Outer cylinder 81b Cam groove 81c Rotation restricting portion 81d Insertion groove

Claims (5)

A fixed cam ring,
A moving cam ring that moves in the direction of the optical axis while rotating following a cam groove formed in an inner peripheral portion of the fixed cam ring;
An inner lens holding portion that moves in an optical axis direction following a cam groove formed in an inner peripheral portion of the moving cam ring;
An outer lens holding portion that moves in the optical axis direction following a cam groove formed on the outer peripheral portion of the movable cam ring;
An outer cylinder which is provided between the outer lens holding portion and the fixed cam ring, is fixed to the moving cam ring, and moves in the optical axis direction while rotating integrally with the moving cam ring;
The outer lens holding portion is inserted into a curved inner circumferential groove formed on the inner circumferential portion of the outer cylinder and having the same locus as the cam groove formed on the outer circumferential portion of the movable cam ring. A protrusion is provided,
The outer cylinder is formed with a linear insertion groove extending from the opening formed at the image plane side end of the peripheral wall of the outer cylinder to the subject side along the optical axis direction.
The outer lens holding portion is built into the outer cylinder by inserting the protrusion from the opening in the optical axis direction,
At the end on the feeding side of the inner circumferential groove, there is provided a rotation restricting portion on which the projection can abut in the circumferential direction at a connection portion between the end on the feeding side and the end on the subject side of the insertion groove.
An optical apparatus characterized by being. The inner lens holding unit includes a first lens holding unit, a second lens holding unit, and a third lens holding unit that are sequentially arranged from the subject side toward the image plane side.
On the image plane side of the third lens holding portion, a fourth lens holding portion in a state of being restricted in rotation by the fixed cam ring is provided so as to be movable in the optical axis direction.
Between the second lens holding part and the fourth lens holding part, a first rotation restricting engagement part for restricting the rotation of the second lens holding part is provided,
Between the second lens holding part and the first lens holding part, a second rotation restriction engaging part for restricting the rotation of the first lens holding part is provided,
Between the second lens holding part and the third lens holding part, a third rotation restricting engagement part for restricting the rotation of the third lens holding part is provided,
The fourth rotation restricting / engaging portion for restricting rotation of the outer lens holding portion is provided between the outer lens holding portion and the first lens holding portion. Optical equipment. The movable cam ring and the outer cylinder are fixed to each other by engagement by a snap fit structure ,
3. The optical apparatus according to claim 1, wherein the engaging portion is exposed to the outside when the movable cam ring moves to the vicinity of an end portion on a feeding side with respect to the fixed cam ring. . 4. The projection of the outer lens holding portion is provided on the outer diameter side of a cam follower that follows the cam groove formed on the outer peripheral portion of the movable cam ring . The optical apparatus according to one item. 5. The projection according to claim 1, wherein the protrusion of the outer lens holding portion is engaged with the inner circumferential groove formed in the outer cylinder with a gap. 6. Optical equipment.

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