JP6271996B2 - Lens barrel and photographing apparatus - Google Patents

Description

  The present invention relates to a lens barrel and a photographing apparatus.

  An imaging apparatus having a zoom mechanism that moves a plurality of optical lenses in the optical axis direction to change the imaging magnification has been proposed. Patent Document 1 discloses a camera including a lens barrel that extends from a stored state to a photographing state. This camera has a barrier on the front side of the lens barrel. Patent Document 2 discloses a lens barrel having a lens barrier.

JP 2001-337259 A JP 2011-154167 A

  The lens barrel is housed inside a camera housing called a main body, and is generally protected from external pressure by the main body when not in use. However, when the photographing magnification is increased or the photographing performance is improved, the lens barrel may protrude from the housing. However, in the camera of Patent Document 2, since the distance between the barrier group and the lens group is increased during storage, the camera is affected by disturbance during storage.

  In recent years, there has been a demand for an imaging apparatus that increases the strength from disturbance while reducing the size of the lens barrel. Conventionally, there has been proposed an imaging device that can prevent the lens barrel from being largely destroyed when a force is applied to the barrier group from the front while the distance between the barrier group and the lens group is wide when the lens barrel is stored. It has not been.

  An object of the present invention is to provide a lens barrel that can prevent a large breakage when a force is applied to the barrier group from the front during storage.

  A lens barrel according to an embodiment of the present invention includes a movable cam ring, a lens group that follows a cam groove provided on an outer periphery of the movable cam ring, and a barrier group that is disposed closer to the subject side than the lens group, An outer cylinder means disposed on the outer peripheral side of the lens group and the barrier group and connected to the movable cam ring. A protrusion having an outer diameter protruding is provided on the subject side of the barrier group, and the protrusion can contact the outer cylinder means when the lens barrel is stored.

  According to the lens barrel of the present invention, when a force is applied to the barrier group from the front when the lens barrel is stored, the lens barrel can be prevented from being largely destroyed.

It is a figure which shows the external appearance of the imaging device which has a lens barrel. It is a figure which shows the external appearance of the imaging device which has a lens barrel. It is a functional block diagram of a digital camera. It is sectional drawing of the accommodation state of a lens-barrel. It is sectional drawing of the drawing-out state of a lens barrel. It is a perspective view of the components currently used inside the lens barrel. It is a back perspective view of the fixed cam ring used inside a lens barrel. It is a disassembled perspective view of a lens barrel. It is a figure explaining operation | movement of the barrier blade | wing with which a barrier group is provided.

  1 and 2 are views showing an external appearance of a photographing apparatus having a lens barrel of the present embodiment. The digital camera 23 is the photographing apparatus of this embodiment. FIG. 3 is a functional block diagram of the digital camera 23. The digital camera 23 has a zoom mechanism that changes the shooting magnification.

  FIG. 1 is a front perspective view of the digital camera 23. FIG. 2 shows a rear view of the digital camera 23. In front of the digital camera 23, there are provided a finder 21 for determining the composition of the subject, auxiliary light 20 for assisting the light source when performing photometric distance measurement, a strobe 22, and a lens barrel 16.

  On the top surface of the digital camera 23, a release button 17, a zoom changeover switch 18, and a power supply changeover button 19 are arranged. Operation buttons 26, 27, 28, 29, 30, and 31 are arranged on the back, and various functions can be switched. In addition, a display (liquid crystal means) 25 having an LCD and a viewfinder eyepiece 24 are disposed on the back surface. The display 25 is image display means, and displays image data stored in the memory 39 and image data read from the memory card on the screen.

  The control unit that controls the digital camera 23 includes the CPU 45, the ROM 44, and the RAM 46 shown in FIG. Processing units such as the release button 17, the operation buttons 26 to 31, the display 25, the memory 39, and the memory card drive 41 are connected via the bus 43.

  The drive circuit 42 connected to the control system via the bus 43 is connected to the zoom mechanism 32, the focus drive mechanism 7, the shutter drive mechanism 33, the aperture drive means 35, the image sensor 10 such as a CCD or CMOS, and the strobe 22. Yes. Each drive is controlled by a signal from the control system.

  The ROM 44 stores a program for controlling each processing unit. The RAM 46 stores data necessary for each control program. The analog signal processing means 36 performs analog processing on the captured image data and outputs it to the A / D converter 37. The A / D converter 37 converts the captured analog data into digital data. This digital data is output to the digital signal processing means 38. The digital signal processing means 38 processes digital data. Finally, the digital data is stored in the memory 39.

  The compression / decompression unit 40 decompresses image data stored in the memory 39 and image data stored in the memory card drive 41. The control unit displays the decompressed image data 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, the user can delete the image by operating the operation button 26.

  Next, the configuration of the lens barrel 16 will be described. FIG. 4 is a cross-sectional view of the lens barrel stored. FIG. 5 is a cross-sectional view of the lens barrel in the extended state. FIG. 6 is a perspective view of components used in the lens barrel. FIG. 7 is a rear perspective view of a fixed cam ring used inside the lens barrel. FIG. 8 is an exploded perspective view of the lens barrel.

  First, the lens group of this embodiment will be described. The first lens group 1b includes first photographing lens means 1a. The barrier group 1 is disposed in front of the first lens group 1b, that is, on the subject side. A second lens group 2 is disposed behind the first lens group 1 b, and a third lens group 3 is disposed behind the second lens group 2. The second lens group 2 holds second photographic lens means 2b. The third lens group 3 is divided into a shutter portion and a lens holding portion. The third photographic lens means 3a is held by the third lens holding part 13, and a shutter part is provided behind it.

  A fourth lens group 4 which is an anti-vibration lens group is disposed behind the third lens group 3, and the fourth lens group 4 holds fourth photographing lens means 4a. A sixth lens group 6 that is a focus unit is disposed behind the fourth lens group 4.

  The sixth lens group 6 is divided into a focus base means 6 and a focus lens 5a. The focus lens 5a is held by the focus lens holding means 5. The focus lens holding means 5 is driven by a focus motor means 7 fixed to the focus base means 6 and moves in the optical axis direction to focus the camera.

  A movable cam ring 8 is disposed on the outer periphery of the second lens group 2, the third lens group 3, and the fourth lens group 4. The second lens group 2, the third lens group 3, and the fourth lens group 4 can move in the optical axis direction by following a plurality of cam grooves provided on the inner periphery of the movable cam ring 8. Further, by following the cam groove provided on the outer periphery of the movable cam ring 8, the first lens group 1b can move in the optical axis direction.

  The barrier group 1 is disposed on the outer periphery of the first lens group 1b. The barrier group 1 follows a cam groove provided on the outer periphery of the movable cam ring 8 and different from the cam groove followed by the first lens group 1b. That is, the movement trajectories of the first lens group 1b and the barrier group 1 are different.

  A fixed cam ring 9 is disposed on the outer periphery of the moving cam ring 8. The moving cam ring 8 follows the cam groove provided on the inner periphery of the fixed cam ring 9 and moves in the optical axis direction. A drive ring 14 is disposed on the outer periphery of the fixed cam ring 9, and the outer periphery thereof is protected by the cover means 12.

  The image sensor 10 is disposed on the rearmost surface of the lens barrel 16, and the image sensor 10 is held by the image sensor holding means 11. The sixth lens group 6 follows a cam groove provided on the inner periphery of the drive ring 14. The sixth lens is regulated to go straight by the fixed cam ring 9. When the drive ring 14 rotates the outer periphery of the fixed cam ring 9 by the zoom mechanism 32, the sixth lens group 6 moves back and forth in the optical axis direction along the cam groove.

  The moving cam ring 8 itself also rotates on the inner periphery of the fixed cam ring 9 as the drive ring 14 rotates, and the moving cam ring follower means 8 c provided on the moving cam ring 8 is fixed to the fixed cam groove 9 a of the fixed cam ring 9. By following this, it moves back and forth in the optical axis direction.

  As the moving cam ring 8 rotates, the barrier group 1, the first lens group 1b, the second lens group 2, the third lens group 3, the fourth lens group 4, and the sixth lens group 6 move in the optical axis direction. To do. On the focus base of the sixth lens group 6, a straight travel restricting means 15 is integrally provided. The straight travel restricting means 15 holds the straight travel restricting means 3 b provided integrally with the shutter means connected to the third lens group 3.

  The straight travel regulation means 3b has a sheath shape, and the straight travel regulation means 15 is inserted into the sheath. The straight travel regulation means 3b and the straight travel regulation means 15 are arranged in pairs. A fourth lens group linear advancement restricting means 3c is provided on the outer peripheral portion of the sheath shape of the linear movement restricting means 3b, and the fourth lens group linear advancement restricting means 4b provided in the fourth lens group 4 is linearly restricted. The

  The second lens group rectilinear advance restricting means 13 a provided in the second lens group 2 is regulated by the second lens group rectilinear advance restricting means 13 a provided in the third lens group 3. In addition, the first lens group is regulated to go straight by the first lens group rectilinear regulation means 2 a provided in the second lens group 2.

  Outer cylinder means 8a is fixed to the outer peripheral side of the movable cam ring 8 and the first lens group 1b. The outer cylinder means 8a is provided with three preliminary cam follower means 8b having a trapezoidal cross section on the outer periphery. The spare cam follower means 8 b is inserted into a spare cam groove 9 b provided on the inner periphery of the fixed cam ring 9. The outer cylinder means 8a is connected to the moving cam ring 8 by three snap fit means 8d.

  Next, the assembly of the lens barrel will be described step by step. First, the internal lens groups are assembled to the movable cam ring 8 alone. Specifically, the movable cam ring 8 is assembled to the fixed cam ring 9. The moving cam ring 8 is incorporated into the fixed cam ring 9 from the back surface of the fixed cam ring 9. A moving cam ring follower means 8 c provided on the moving cam ring 8 can be incorporated in a fixed cam groove 9 a provided on the fixed cam ring 9. A moving cam ring assembly groove 9e is provided at the extended end of the storage portion where the moving cam ring 8 is further rotated from the storage end, and the moving cam ring follower means 8c is inserted into the moving cam ring assembly groove 9e from the back to each other. Can be connected.

  The drive ring 14 is incorporated, and the cover cylinder 12 covers the periphery, and the image sensor holding means 11 is assembled from the back to cover the image sensor holding means 11. In this state, the assembly is not yet completed, but the lens can be adjusted for alignment of the internal optical axis. A step of improving the optical performance by aligning the lens tilt or eccentricity may be executed. Thereafter, the movable cam ring 8 is rotated in the feeding direction to rotate to the feeding side assembly phase. Then, the first lens group 1b, which is a lens group outside the movable cam ring 8, is assembled, and the barrier group 1 is further assembled. Subsequently, the moving cam ring 8 is once rotated in the storage direction and moved to the feeding side mechanical end. In this state, the outer cylinder means 8a is incorporated on the outer periphery of the first lens group 1b and the movable cam ring 8.

  The moving cam ring 8 moves in the optical axis direction while rotating along the cam groove 9 a, but the auxiliary cam follower means 8 b follows the inside of the auxiliary cam groove 9 b inside the fixed cam ring 9. At this time, the preliminary cam follower means 8b and the preliminary cam groove 9b have a slight gap.

FIG. 9 is a diagram for explaining the operation of the barrier blades provided in the barrier group.
At the front end of the barrier group 1, a barrier blade 1d, which is a blade member, is provided. As shown in FIG. 9A, the barrier blade 1d is opened when the lens barrel is in a shootable state (the extended state in which the lens barrel is extended to the subject side). When the lens barrel is stored, the barrier blade 1d is closed. In order to increase the opening of the barrier, the barrier group 1 is provided with a protruding portion 1c formed by partially protruding the outer diameter of the barrier portion on the subject side. Then, as shown in FIG. 9B, when the lens barrel moves from the retracted position to the photographing enabled position, the barrier blade 1d is inserted into the protrusion 1c.

  When the lens barrel 16 is in the retracted state, the first photographing lens means 1a is located away from the barrier blade 1d so that the barrier blade 1d can be closed. When the lens barrel is moved from the retracted state to the position where the photographing is possible, the barrier group 1 and the first lens group 1b approach each other, and the lens included in the first lens group 1b is inside the opening where the barrier blade 1d is opened. (First photographing lens means 1a) enters. By doing so, the barrier opening of the barrier means 1 can be made as small as possible.

  When the barrier group and the first lens group are moved by different cam tracks, the conventional lens barrel holds the barrier group with a gap in the front during storage and is held only by cam engagement. Therefore, it is easy to destroy when pushed forward in the stowed state. Therefore, the lens barrel of the present embodiment holds the protruding portion 1c provided in the barrier group 1 so as to be in contact with the outer cylinder means 8a fixed to the movable cam ring 8. That is, when the lens barrel is stored, the protrusion 1c can come into contact with the outer cylinder means 8a. As a result, even when a force is applied to the barrier group 1 from the front during the storage of the lens barrel, the protrusion 1c can be held in contact with the outer cylinder means 8a to prevent a large breakage.

  Further, when the lens barrel receives a load from the subject side, the auxiliary cam follower means 8 b provided in the outer cylinder means 8 a comes into contact with the auxiliary cam groove 9 b provided in the fixed cam ring 9. Thereby, destruction of the whole lens barrel can be prevented. By adopting the above configuration, a lens barrel that is resistant to external impact can be obtained.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

DESCRIPTION OF SYMBOLS 1 Barrier group 1b 1st lens group 1c Projection part 8a Outer cylinder means

Claims (4)

A moving cam ring,
A lens group that follows a first cam groove provided on the inner periphery of the movable cam ring;
A barrier ring that is disposed closer to the subject than the lens group and follows a second cam groove provided on the outer periphery of the movable cam ring ;
Is disposed on the outer peripheral side of the front Symbol barrier ring, the moving cam ring, is formed on the object side of the moving cam ring, a lens barrel having an outer barrel means extending the object side,
On the subject side of the barrier ring, a protrusion having a larger outer diameter than the diameter of the ring in which a part of the lenses of the lens group is positioned when the lens barrel is extended is provided.
When the lens barrel is extended, a barrier blade formed on the subject side of the barrier ring is inserted into the protrusion,
The lens barrel according to claim 1, wherein the protruding portion is capable of contacting the outer cylinder means when the lens barrel is stored. The barrier blade opens when the lens barrel is in a shooting state where the lens barrel is extended to the subject side,
When the lens barrel is moved from the position of the stored state in the position of the photographing state, the lens according to claim 1, lens included in the lens group to open interior of the barrier blades characterized in that the invading A lens barrel. A fixed cam ring provided on the outer peripheral side of the movable cam ring;
The moving cam ring follows a third cam groove provided on the inner periphery of the fixed cam ring,
A cam follower is provided on the outer periphery of the outer cylinder means,
The fixed cam ring is provided with a preliminary cam groove into which the cam follower is inserted.
The lens barrel according to claim 1 or 2 , wherein when the lens barrel receives a load from a subject side, the cam follower comes into contact with the spare cam groove. An imaging apparatus comprising the lens barrel according to any one of claims 1 to 3 .