WO2019181679A1 - Lens barrel - Google Patents

Abstract

Provided is a lens barrel that can be driven smoothly while preventing backlash. A fixed cylinder (20) comprises a first pin (110) and a second pin (120) that are elastically deformable. The cam cylinder (30) comprises a first groove (130) and a second groove (140) that extend in a direction orthogonal to the optical axis. The second pin (120) is fitted into the second groove (140) and the outer circumference thereof is pressed against the inner circumferential surface of the second groove (140). The first pin (110) has a tapered shape, is fitted into the first groove (130), and has the outer circumference thereof pressed against an edge of the first groove (130). As a result, a force (F1b) in the pressing direction acts on the first pin (110), causing backlash, and backlash between the fixed cylinder (20) and the cam cylinder (30) is eliminated.

Description

Lens barrel

The present invention relates to a lens barrel, and more particularly, to a lens barrel including a first cylinder and a second cylinder that are fitted and relatively rotatably held.

Generally, a lens barrel that employs a cam mechanism includes a fixed barrel and a cam barrel to be fitted, and the lens group is moved by rotating the cam barrel. In this type of lens barrel, there is a problem that if there is a backlash in the fitting between the cam barrel and the fixed barrel, the shaft is displaced, the shaft is tilted, etc., and the optical performance is lowered. Conventionally, an elastic member is disposed between the cam cylinder and the fixed cylinder to remove the backlash (for example, Patent Document 1).

JP 2011-197519

However, when an elastic member is incorporated between the cam cylinder and the fixed cylinder, there is a disadvantage that uneven rotation occurs and the driving of the lens becomes unstable.

The present invention has been made in view of such circumstances, and an object thereof is to provide a lens barrel that can be smoothly driven while preventing backlash.

Measures for solving the above problems are as follows.

(1) A first cylinder and a second cylinder that are fitted and relatively rotatably held, a plurality of elastically deformable pins provided at a plurality of locations of the first cylinder, and a plurality of locations of the second cylinder. And a plurality of grooves into which the plurality of pins are fitted, and a plurality of grooves extending in a direction orthogonal to the optical axis, wherein the plurality of pins are at least one first A pin and at least one second pin. The first pin has a tapered shape with an outer diameter decreasing radially outward with respect to the first tube and the second tube. When the lens is fitted into the groove, the outer peripheral surface of the first pin is pressed against the edge of the groove to urge the first cylinder radially inward with respect to the second cylinder.

According to this aspect, the first cylinder is provided with a plurality of elastically deformable pins. The second cylinder is provided with a plurality of grooves into which the pins are fitted. Each groove is disposed orthogonal to the optical axis. That is, they are arranged along the rotation direction (direction around the axis centered on the optical axis). Therefore, the optical axis direction can be positioned between the first cylinder and the second cylinder by fitting the pin into the groove. Further, the range of rotation can be restricted by defining the length of the groove. The pins provided in the first cylinder are composed of at least a first pin and a second pin. The first pin has a tapered shape, and the outer diameter decreases toward the outer side in the radial direction (the direction toward the outer side in the radial direction) with respect to the first and second cylinders. The first pin is fitted into the groove so that the outer peripheral surface thereof is pressed against the edge of the groove. Since the first pin is elastically deformable, when the first pin is fitted in the groove in this manner, the first tube is urged toward the inner side in the radial direction (the direction toward the inner side in the radial direction) with respect to the second tube. To do. Thereby, the play which arises between the 1st cylinder and the 2nd cylinder can be offset. That is, it can be loosened. Thereby, the play which arises between the 1st cylinder and the 2nd cylinder can be removed. Moreover, since the groove | channel which each pin fits is arrange | positioned along a rotation direction, the rotation operation between a 1st cylinder and a 2nd cylinder is not inhibited. That is, smooth rotation can be ensured.

Note that a normal pin can be used for the shape of the second pin. That is, a pin that comes into contact with the inner wall surface of the groove by being fitted into the groove can be used.

(2) The lens barrel according to (1), wherein the first pin has an arcuate taper shape whose outer diameter is reduced radially outward with respect to the first and second cylinders.

According to this aspect, the first pin has an arcuate taper shape. That is, the outer peripheral cross section has an arc shape. Accordingly, it is possible to prevent the first pin from fitting into the groove so as not to be elastically deformed (so-called biting can be prevented).

(3) The lens barrel according to (1) or (2), wherein the second pin has a shape in which an outer peripheral surface bulges outward in an arc shape.

According to this aspect, the second pin has a shape in which the outer peripheral surface swells in an arc shape toward the outside. Thereby, it can be made to contact | abut on the inner wall face of a groove | channel in the state near a point or a point, and the load concerning a 2nd pin can be reduced.

(4) The first pin has an annular or cylindrical first pin outer peripheral portion disposed concentrically with a gap between the first pin shaft portion and the first pin shaft portion, and a first pin shaft portion. A lens barrel according to any one of (1) to (3), further comprising a first pin support portion that supports the outer periphery of the first pin.

According to this aspect, the first pin has an annular or cylindrical first pin outer peripheral portion disposed concentrically with a gap between the first pin shaft portion and the first pin shaft portion, and the first pin. A first pin support portion that supports the outer peripheral portion of the first pin with respect to the shaft portion. Thereby, only an outer peripheral part can be comprised so that elastic deformation can be carried out to radial direction.

(5) The lens barrel according to (4), wherein the first pin is an integrally molded product made of resin, and is fixed to the first tube by a fastening member inserted coaxially.

According to this aspect, the first pin is constituted by an integrally molded product made of resin. That is, it is injection-molded with a resin using a predetermined mold and configured as an integrally molded product. Moreover, it fixes to a 1st pipe | tube by the fastening member penetrated coaxially. Thereby, it can manufacture easily.

(6) The second pin includes an annular or cylindrical second pin outer peripheral portion disposed concentrically with a gap between the second pin shaft portion and the second pin shaft portion, and a second pin shaft portion. A lens barrel according to any one of (1) to (5), further comprising a second pin support portion that supports an outer peripheral portion of the second pin.

According to this aspect, the second pin has an annular or cylindrical second pin outer peripheral portion disposed concentrically with a gap between the second pin shaft portion and the second pin shaft portion, and the second pin. And a second pin support portion that supports the outer peripheral portion of the second pin with respect to the shaft portion. Thereby, only an outer peripheral part can be comprised so that elastic deformation can be carried out to radial direction.

(7) The lens barrel according to (6), wherein the second pin is an integrally molded product made of resin and is fixed to the first tube by a fastening member inserted coaxially.

According to this aspect, the second pin is formed of an integrally molded product made of resin. That is, it is injection-molded with a resin using a predetermined mold and configured as an integrally molded product. Moreover, it fixes to a 1st pipe | tube by the fastening member penetrated coaxially. Thereby, it can manufacture easily.

(8) The lens barrel according to any one of (1) to (7) above, wherein the groove into which the first pin is fitted has a chamfered edge.

According to this aspect, the edge of the groove into which the first pin is fitted is chamfered. Thereby, the outer peripheral surface of the first pin can be stably brought into contact with the edge of the groove.

(9) From the above (1), three pins are arranged at equal intervals in the first cylinder, one of the three pins is constituted by the first pin, and the other is constituted by the second pin. The lens barrel according to any one of (8).

According to this aspect, the three pins are arranged at equal intervals in the first cylinder. Of the three pins, one is composed of the first pin and the rest is composed of the second pin. Thereby, play can be removed stably.

(10) A pin is fitted into the groove to position the second cylinder relative to the first cylinder in the optical axis direction, and / or the relative rotatable range of the second cylinder relative to the first cylinder. The lens barrel according to any one of (1) to (9), wherein

According to this aspect, the second cylinder is relatively positioned in the optical axis direction with respect to the first cylinder by fitting the pin into the groove. Alternatively, the relative rotatable range of the second cylinder with respect to the first cylinder is regulated by fitting a pin into the groove. Or do both. Thereby, it is not necessary to separately provide positioning means or means for regulating the rotatable range, and the configuration of the lens barrel can be simplified.

(11) The lens barrel according to any one of (1) to (10), wherein the second tube is fitted to the outer periphery of the fixed first tube and the outer periphery of the first tube is rotatably held. .

According to this aspect, the second cylinder is fitted to the outer periphery of the fixed first cylinder, and the outer periphery of the first cylinder is rotatably held. That is, the first cylinder is a so-called fixed cylinder and the second cylinder is a so-called rotating cylinder, and the second cylinder is rotatably held on the outer periphery of the first cylinder.

(12) The lens barrel according to (11), wherein the first cylinder is a fixed cylinder having a rectilinear groove, and the second cylinder is a cam cylinder having a cam groove.

According to this aspect, the first cylinder is constituted by a fixed cylinder provided with a rectilinear groove, and the second cylinder is constituted by a cam cylinder provided with a cam groove.

According to the present invention, it is possible to drive smoothly while preventing backlash.

Sectional drawing which shows schematic structure of the interchangeable lens to which this invention was applied (at the time of a wide angle) Sectional drawing which shows schematic structure of the interchangeable lens to which this invention was applied (at the time of a telephoto) The figure which shows the movement state of each lens group at the time of zooming operation 4-4 sectional view of FIG. Sectional drawing of the structure in connection with the drive of a 2nd lens holding frame 6-6 sectional view of FIG. Sectional drawing of the structure in connection with the drive of a 3rd lens holding frame and a 4th lens holding frame 8-8 sectional view of FIG. 9-9 sectional view of FIG. 10-10 sectional view of FIG. The perspective view which shows the structure of a 1st pin Front view showing the configuration of the first pin Plan view showing the configuration of the first pin Bottom view showing the configuration of the first pin 15-15 sectional view of FIG. 16-16 sectional view of FIG. The perspective view which shows the structure of a 2nd pin Front view showing the configuration of the second pin Plan view showing the configuration of the second pin Bottom view showing the configuration of the second pin 21-21 sectional view of FIG. 22-22 sectional view of FIG. Sectional drawing which shows the structure of a 1st groove | channel Sectional drawing which shows the structure of a 2nd groove | channel The figure which shows the fitting state of a 1st pin and a 1st groove | channel. The figure which shows the fitting state of a 2nd pin and a 2nd groove | channel. The figure which shows another example of a 1st pin The figure which shows another example of a 2nd pin Sectional drawing which shows the structure of the mechanism which removes the backlash between a fixed cylinder and a cam cylinder with two pins and two grooves.

Hereinafter, preferred embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

Here, a case where the present invention is applied to an interchangeable lens of an interchangeable lens camera will be described as an example. In particular, a case where the present invention is applied to an interchangeable lens having a function of zooming by moving a lens group by a cam mechanism will be described as an example.

[Configuration of interchangeable lens]
1 and 2 are sectional views showing a schematic configuration of an interchangeable lens to which the present invention is applied. FIG. 1 shows a state at the wide-angle end, and FIG. 2 shows a state at the telephoto end.

The interchangeable lens 1 includes a mount 12 at the base end portion (image side end portion) of the lens barrel 10. The interchangeable lens 1 is detachably attached to the camera body via the mount 12. A plurality of lens groups are arranged inside the lens barrel 10.

<Lens configuration>
FIG. 3 is a diagram illustrating a moving state of each lens group when the zooming operation is performed. FIG. 2A shows the lens arrangement at the wide-angle end, and FIG. 2B shows the lens arrangement at the telephoto end.

The lens barrel 10 includes a first lens group G1, a second lens group G2, a third lens group G3, a fourth lens group G4, and a fifth lens group G5 in that order from the object side. Each lens group includes at least one lens. Each lens group is arranged along the optical axis Z.

Among the first lens group G1 to the fifth lens group, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 are lens groups that move during zooming. On the other hand, the fifth lens group G5 is a fixed lens group upon zooming.

The second lens group G2 includes a second lens group front group G2a and a second lens group rear group G2b in order from the object side. The second lens group rear group G2b constitutes a focus lens group and moves independently. Focusing is performed by moving the second lens group rear group G2b along the optical axis Z.

The third lens group G3 includes a diaphragm St. The diaphragm St is constituted by, for example, an iris diaphragm. The amount of light is adjusted by adjusting the opening amount of the diaphragm St.

<Structure of lens barrel>
The lens barrel 10 includes a fixed barrel 20, a cam barrel 30, a movable barrel 40 and an exterior barrel 50. The lens barrel 10 has a first lens holding frame LF1 for holding the first lens group G1, a second lens holding frame LF2 for holding the second lens group G2, and a third lens holding for holding the third lens group G3. A frame LF3, a fourth lens holding frame LF4 that holds the fourth lens group G4, and a fifth lens holding frame LF5 that holds the fifth lens group G5 are provided.

The fixed cylinder 20, the cam cylinder 30, and the movable cylinder 40 are fitted from the inside in the order of the fixed cylinder 20, the cam cylinder 30, and the movable cylinder 40 to form a multiple structure cylinder. Specifically, the cam cylinder 30 is fitted to the outer periphery of the fixed cylinder 20, and the moving cylinder 40 is fitted to the outer periphery of the cam cylinder 30 to form a multiple structure cylinder.

<Fixed cylinder>
The fixed cylinder 20 is configured by a cylindrical cylinder, for example, a metal such as aluminum. The fixed cylinder 20 includes a mount 12 at its base end (image side end). Therefore, when the interchangeable lens 1 is attached to the camera body, the fixed cylinder 20 is fixed to the camera body. The fixed cylinder 20 is provided with a plurality of rectilinear grooves extending along the optical axis Z.

<Cam barrel>
The cam cylinder 30 is constituted by a cylindrical cylinder, for example, a metal such as aluminum. The cam cylinder 30 is fitted to the outer periphery of the fixed cylinder 20 so that the outer periphery of the fixed cylinder 20 is rotatably held in the circumferential direction. The fixed cylinder 20 is an example of a first cylinder, and the cam cylinder 30 is an example of a second cylinder. The cam cylinder 30 is provided with a plurality of cam grooves. For convenience, FIGS. 1 and 2 show only one cam groove (the first cam groove 30A for driving the movable cylinder 40).

The cam cylinder 30 is provided with a mechanism for positioning the cam cylinder 30 with respect to the fixed cylinder 20 in the optical axis direction and removing backlash between the cam cylinder 30 and the fixed cylinder 20. This function will be described later.

<Moving tube>
The moving cylinder 40 is configured by a cylindrical cylinder. The moving cylinder 40 is fitted to the outer periphery of the cam cylinder 30 so that the outer periphery of the fixed cylinder 20 is held movably along the optical axis. A mechanism for moving the movable cylinder 40 will be described later.

<Exterior cylinder>
The exterior cylinder 50 is configured by a cylindrical cylinder. The exterior cylinder 50 constitutes the exterior of the interchangeable lens 1. The outer cylinder 50 is fixed to the fixed cylinder 20 at the base end portion. Therefore, when the interchangeable lens 1 is attached to the camera body, the outer tube 50 is also fixed to the camera body.

The exterior cylinder 50 is provided with a zoom ring 52 as a zoom operation means. The zoom ring 52 is provided so that the outer periphery of the outer cylinder 50 is rotatable in the circumferential direction. The zoom ring 52 is connected to the cam cylinder 30 via a connecting member (not shown), and the rotation is transmitted to the cam cylinder 30. Therefore, when the zoom ring 52 is rotated, the cam cylinder 30 is rotated.

Also, the exterior cylinder 50 is provided with a focus ring 54 as a focus operation means. The focus ring 54 is provided so that the outer periphery of the outer casing 50 can be rotated in the circumferential direction. The rotation amount of the focus ring 54 is detected by a sensor (not shown).

<First lens holding frame>
The first lens holding frame LF1 is formed of a cylindrical tube. The first lens holding frame LF1 holds the first lens group G1 coaxially with the inner periphery thereof.

The first lens holding frame LF1 is disposed coaxially with the inner periphery of the movable barrel 40 and is held integrally with the movable barrel 40. Therefore, it moves together with the moving cylinder 40. The first lens holding frame LF1 is held at the distal end portion (the end portion on the object side) of the movable barrel 40.

<Second lens holding frame>
The second lens holding frame LF2 is configured by a cylindrical tube. The second lens holding frame LF2 holds the second lens group G2 coaxially with the inner periphery thereof.

As described above, the second lens group G2 includes the second lens group front group G2a and the second lens group rear group G2b. The second lens group front group G2a is integrally held on the same axis as the second lens holding frame LF2. On the other hand, the second lens group rear group G2b is movably supported by a pair of guide shafts GS provided on the inner periphery of the second lens holding frame LF2. The pair of guide shafts GS are arranged along the optical axis Z. As a result, the second lens group rear group G2b is held movably independently. The second lens holding frame LF2 is provided with a linear motor (not shown) as driving means for the second lens group rear group G2b. The second lens group rear group G2b is driven to move by the linear motor.

The second lens holding frame LF2 is disposed coaxially with the inner peripheral portion of the fixed cylinder 20. The second lens holding frame LF <b> 2 is held movably along the optical axis Z on the inner periphery of the fixed cylinder 20. A mechanism for moving the second lens holding frame LF2 will be described later.

<Third lens holding frame>
The third lens holding frame LF3 is configured by a cylindrical tube. The third lens holding frame LF3 holds the third lens group G3 coaxially with the inner periphery thereof. Further, the third lens holding frame LF3 holds the aperture unit SU coaxially with the inner periphery thereof.

The third lens holding frame LF3 is disposed coaxially with the inner peripheral portion of the fixed cylinder 20. The third lens holding frame LF3 is held movably along the optical axis Z on the inner peripheral portion of the fixed barrel 20. A mechanism for moving the third lens holding frame LF3 will be described later.

<Fourth lens holding frame>
The fourth lens holding frame LF4 is configured by a cylindrical tube. The fourth lens holding frame LF4 holds the fourth lens group G4 coaxially with the inner periphery thereof.

The fourth lens holding frame LF4 is disposed coaxially with the inner peripheral portion of the fixed cylinder 20. The fourth lens holding frame LF4 is held movably along the optical axis Z on the inner peripheral portion of the fixed cylinder 20. A mechanism for moving the fourth lens holding frame LF4 will be described later.

<Fifth lens holding frame>
The fifth lens holding frame LF5 is configured by a cylindrical tube. The fifth lens holding frame LF5 holds the fifth lens group G5 coaxially with the inner periphery thereof.

The fifth lens holding frame LF5 is disposed coaxially with the inner peripheral portion of the fixed cylinder 20. The fifth lens holding frame LF5 is integrally held by the fixed cylinder 20.

<Driving mechanism for moving cylinder>
4 is a cross-sectional view taken along line 4-4 of FIG.

The movable cylinder 40 includes three first cam followers 60A on the inner periphery of the base end (image side end). The three first cam followers 60A are arranged on the same circumference of the inner peripheral portion of the movable barrel 40 and are arranged at equal intervals. Each first cam follower 60 </ b> A is screwed with a screw (not shown) and attached to the movable cylinder 40.

The cam cylinder 30 includes three first cam grooves 30A having a predetermined locus. The three first cam grooves 30A are arranged at equal intervals corresponding to the three first cam followers 60A.

The fixed cylinder 20 includes three first rectilinear grooves 20A extending along the optical axis Z. The three first rectilinear grooves 20A are arranged at equal intervals corresponding to the three first cam followers 60A.

The three first cam followers 60A provided in the moving cylinder 40 are fitted into the three first cam grooves 30A and the first rectilinear grooves 20A, respectively. Thereby, when the cam cylinder 30 is rotated, the movable cylinder 40 moves along the optical axis Z by the action of the cam.

<< Drive mechanism of second lens holding frame >>
FIG. 5 is a cross-sectional view of a configuration relating to driving of the second lens holding frame. FIG. 6 is a cross-sectional view taken along the line 6-6 in FIG.

The second lens holding frame LF2 includes three second cam followers 60B on the outer periphery. The three second cam followers 60B are arranged on the same circumference of the outer peripheral portion of the second lens holding frame LF2, and are arranged at equal intervals. Each second cam follower 60B is screwed with a screw (not shown) and attached to the second lens holding frame LF2.

The cam cylinder 30 includes three second cam grooves 30B having a predetermined locus. The three second cam grooves 30B are arranged at equal intervals corresponding to the three second cam followers 60B. In FIG. 5, only the second cam groove 30B is shown for convenience.

The fixed cylinder 20 includes three second rectilinear grooves 20B extending along the optical axis Z. The three second rectilinear grooves 20B are arranged at equal intervals corresponding to the three second cam followers 60B.

The three second cam followers 60B provided in the second lens holding frame LF2 are fitted into the three second cam grooves 30B and the second rectilinear grooves 20B, respectively. Accordingly, when the cam cylinder 30 is rotated, the second lens holding frame LF2 moves along the optical axis Z by the action of the cam.

<< Driving mechanism of third lens holding frame and fourth lens holding frame >>
FIG. 7 is a cross-sectional view of a configuration relating to driving of the third lens holding frame and the fourth lens holding frame. 8 is a sectional view taken along the line 8-8 in FIG. 7, and FIG. 9 is a sectional view taken along the line 9-9 in FIG.

The third lens holding frame LF3 includes three third cam followers 60C on the outer periphery. The three third cam followers 60C are arranged on the same circumference of the outer peripheral portion of the third lens holding frame LF3, and are arranged at equal intervals. Each third cam follower 60C is screwed with a screw (not shown) and attached to the third lens holding frame LF3.

In addition, the fourth lens holding frame LF4 includes three fourth cam followers 60D on the outer peripheral portion. The three fourth cam followers 60D are arranged on the same circumference of the outer periphery of the fourth lens holding frame LF4 and are arranged at equal intervals. Each fourth cam follower 60D is screwed with a screw (not shown) and attached to the fourth lens holding frame LF4.

The cam cylinder 30 includes three third cam grooves 30C and a fourth cam groove 30D having a predetermined locus. The three third cam grooves 30C are arranged at equal intervals corresponding to the three third cam followers 60C. Further, the three fourth cam grooves 30D are arranged at equal intervals corresponding to the three fourth cam followers 60D. In FIG. 5, only the third cam groove 30C and the fourth cam groove 30D are shown for convenience.

The fixed cylinder 20 includes three common rectilinear grooves 20CD extending along the optical axis Z. The three common rectilinear grooves 20CD are arranged at equal intervals corresponding to the three third cam followers 60C and the fourth cam followers 60D.

The three third cam followers 60C provided in the third lens holding frame LF3 are fitted into the three third cam grooves 30C and the common rectilinear groove 20CD, respectively. Further, the three fourth cam followers 60D provided in the fourth lens holding frame LF4 are fitted into the three fourth cam grooves 30D and the common rectilinear groove 20CD, respectively. Accordingly, when the cam cylinder 30 is rotated, the third lens holding frame LF3 and the fourth lens holding frame LF4 move along the optical axis Z by the action of the cam.

<< Cam barrel positioning and backlash removal mechanism >>
[Configuration of cam cylinder positioning and backlash removal mechanism]
As described above, the cam cylinder 30 is provided with a mechanism that positions the cam cylinder 30 in the optical axis direction with respect to the fixed cylinder 20 and removes play between the cam cylinder 30 and the fixed cylinder 20. This mechanism is composed of a plurality of pins provided at a plurality of positions of the fixed cylinder 20 (first cylinder) and a plurality of grooves provided at a plurality of positions of the cam cylinder 30 (second cylinder).

FIG. 10 is a cross-sectional view taken along the line 10-10 in FIG.

The three pins are arranged on the same circumference of the outer peripheral portion of the fixed cylinder 20 and are arranged at equal intervals. The three pins are composed of two types of pins having different shapes. One is a first pin 110 and the other is a second pin 120. In the lens barrel 10 of the present embodiment, one of the three lens barrels is composed of the first pin 110 and the rest is composed of the second pin 120.

The three grooves include a first groove 130 into which the first pin 110 is fitted and a second groove 140 into which the second pin 120 is fitted. The first groove 130 and the second groove 140 are disposed at regular intervals on the same circumference of the circumferential surface of the cam cylinder 30 as grooves extending in a direction orthogonal to the optical axis Z.

〔pin〕
(1) First Pin FIG. 11 is a perspective view showing the configuration of the first pin. FIG. 12 is a front view showing the configuration of the first pin. FIG. 13 is a plan view showing the configuration of the first pin. FIG. 14 is a bottom view showing the configuration of the first pin. 15 is a cross-sectional view taken along the line 15-15 in FIG. 16 is a cross-sectional view taken along the line 16-16 in FIG.

The first pin 110 has a tapered shape in which the outer diameter decreases toward the tip (end portion radially outward with respect to the fixed cylinder 20 and the cam cylinder 30). In particular, the first pin 110 of the present embodiment has an arcuate cross section on the outer periphery, and has an arcuate taper shape.

The first pin 110 includes a first pin shaft portion 110a, an annular first pin outer peripheral portion 110b disposed concentrically with a gap between the first pin shaft portion 110a, and a first pin shaft portion 110a. And a first pin support portion 110c that supports the first pin outer peripheral portion 110b.

The first pin shaft portion 110a has a hollow cylindrical shape, and has a hollow portion 110f along the shaft. The hollow portion 110f functions as a screw insertion portion when the first pin 110 is attached to the fixed cylinder 20 with a screw.

The first pin shaft portion 110a has a circular recess 110d on the end surface (upper surface) on the tip side. The recessed portion 110d functions as a seat portion for the screw when the first pin 110 is attached to the fixed cylinder 20 with a screw. The first pin shaft portion 110a has a positioning hole 110e on the end surface (bottom surface) on the base end side (see FIG. 23). The positioning hole 110e has a function of positioning the first pin 110 by fitting the boss 150a provided on the fixed cylinder 20 side when the first pin 110 is attached to the fixed cylinder 20 (see FIG. 23).

The first pin outer peripheral portion 110b constitutes the main body of the first pin 110. Therefore, the outer shape has an arcuate taper shape whose outer diameter decreases toward the tip. The first pin outer peripheral portion 110b is configured to be elastically deformable, and is disposed concentrically with the first pin shaft portion 110a.

The first pin support portion 110c supports the first pin outer peripheral portion 110b at two locations on the inner peripheral portion of the first pin outer peripheral portion 110b.

The first pin 110 is injection-molded with a resin using a predetermined mold and configured as an integrally molded product. For example, POM (POM: Polyoxymethylene or Polyacetal / polyoxymethylene or polyacetal) is injection-molded to form an integrally molded product. The first pin outer peripheral portion 110b is configured to be elastically deformable by using elasticity of resin. The first pin 110 is screwed to the fixed cylinder 20 by passing a screw as a fastening member through the hollow portion of the first pin shaft portion 110a.

(2) Second Pin FIG. 17 is a perspective view showing the configuration of the second pin. FIG. 18 is a front view showing the configuration of the second pin. FIG. 19 is a plan view showing the configuration of the second pin. FIG. 20 is a bottom view showing the configuration of the second pin. 21 is a cross-sectional view taken along line 21-21 in FIG. 22 is a cross-sectional view taken along the line 22-22 in FIG.

The second pin 120 has a shape (so-called barrel shape) in which the outer peripheral surface swells in an arc shape toward the outside. The second pin 120 includes a second pin shaft portion 120a, an annular second pin outer peripheral portion 120b disposed concentrically with a gap between the second pin shaft portion 120a, and a second pin shaft portion 120a. And a second pin support portion 120c for supporting the second pin outer peripheral portion 120b.

The second pin shaft portion 120a has a hollow cylindrical shape and has a hollow portion 90f along the shaft. The hollow portion 120f functions as a screw insertion portion when the second pin 120 is attached to the fixed cylinder 20 with a screw.

The second pin shaft portion 120a has a circular recess 120d on the end surface (upper surface) on the tip side. The concave portion 120d functions as a seat portion of the screw when the second pin 120 is attached to the fixed cylinder 20 with a screw (see FIG. 24). The second pin shaft portion 120a has a positioning hole 120e on the end surface (bottom surface) on the base end side. The positioning hole 120e has a function of positioning the second pin 120 by fitting a boss 160a provided on the fixed cylinder 20 side when the second pin 120 is attached to the fixed cylinder 20 (see FIG. 24).

The second pin outer peripheral portion 120b constitutes the main body of the second pin 120. Therefore, the outer shape has a shape (so-called barrel shape) in which the outer peripheral surface swells in an arc shape toward the outside. The second pin outer peripheral portion 120b is configured to be elastically deformable, and is disposed concentrically with the second pin shaft portion 120a.

The second pin support portion 120c supports the second pin outer peripheral portion 120b at two locations on the inner peripheral portion of the second pin outer peripheral portion 120b.

The second pin 120 is injection-molded with a resin using a predetermined mold and configured as an integrally molded product. For example, it is injection molded by POM and configured as an integrally molded product. The 2nd pin outer peripheral part 120b is comprised so that elastic deformation is possible using the elasticity by resin. The second pin 120 is screwed to the fixed cylinder 20 by passing a screw as a fastening member through the hollow portion of the second pin shaft portion 120a.

〔groove〕
(1) First Groove FIG. 23 is a cross-sectional view showing the configuration of the first groove. The figure shows a cross section parallel to the optical axis Z.

As shown in the figure, the first groove 130 has a structure in which the width is switched in two stages, and has a wide wide portion 130a and a narrow fitting portion 130b. The wide portion 130 a is located inside the cam cylinder 30 in the radial direction.

In the first groove 130, the fitting portion 130 b substantially constitutes a fitting groove, and the wide portion 130 a is constituted as a non-contact region with respect to the first pin 110. Accordingly, the wide portion 130 a has a width larger than the outer diameter of the first pin 110. On the other hand, the fitting portion 130 b has a width that is slightly narrower than the outer diameter of the first pin 110. Therefore, when the first pin 110 is fitted into the fitting portion 130b, the first pin 110 is elastically deformed and fitted into the fitting portion 130b (collapsed and fitted).

The first groove 130 is chamfered at the edge (the inner edge in the radial direction of the cam cylinder 30) 130c of the fitting portion 130b (so-called C chamfering). The edge portion 130c functions as a contact portion with the first pin 110.

(2) Second Groove FIG. 24 is a cross-sectional view showing the configuration of the second groove. The figure shows a cross section parallel to the optical axis Z.

As shown in the figure, the second groove 140 has a certain width. The second groove 140 has a width that is slightly narrower than the outer diameter of the second pin 120. Therefore, when the second pin 120 is fitted into the second groove 140, the second pin 120 is elastically deformed and fitted into the second groove 140 (collapsed and fitted).

The outer peripheral surface of the second pin 120 fitted in the second groove 140 is pressed against the inner wall surface 140a of the second groove 140. Since the second pin 120 has a shape in which the outer peripheral surface swells in an arc shape toward the outside, the second pin 120 contacts the inner wall surface 140a of the second groove 140 in a state close to a point.

[Pin installation]
(1) Attachment of First Pin As shown in FIG. 23, the fixed cylinder 20 is provided with a first pin attachment hole 150 at a position where the first pin 110 is attached.

The first pin mounting hole 150 is formed of a circular recess, and has an inner diameter that is the same as (or slightly smaller than) the outer diameter of the first pin shaft portion 110a of the first pin 110. The first pin 110 is attached to the fixed cylinder 20 by fitting the first pin shaft portion 110 a into the first pin attachment hole 150.

The first pin mounting hole 150 has a boss 150a at the bottom. The boss 150a is fitted into a positioning hole 110e provided on the bottom surface of the first pin shaft portion 110a. The first pin 110 is positioned by attaching the first pin 110 so that the boss 150a fits into the positioning hole 110e. When the first pin 110 is fitted in the first groove 130, the first pin support portion 110 c is positioned so as to be positioned at the center in the width direction of the first groove 130.

The first pin mounting hole 150 has a screw hole 150b at the center of the bottom. The first pin 110 attached to the first pin attachment hole 150 is fixed to the fixed cylinder 20 by screwing a first pin fixing screw 152 into the screw hole 150b. The first pin fixing screw 152 is inserted into the hollow portion 110f of the first pin shaft portion 110a and screwed into the screw hole 150b. The first pin fixing screw 152 is an example of a fastening member.

(2) Attachment of Second Pin As shown in FIG. 24, the fixed cylinder 20 is provided with a second pin attachment hole 160 at a position where the second pin 120 is attached.

The second pin mounting hole 160 is formed of a circular recess, and has an inner diameter that is the same as (or slightly smaller than) the outer diameter of the second pin shaft portion 120a of the second pin 120. The second pin 120 is attached to the fixed cylinder 20 by fitting the second pin shaft portion 120 a into the second pin attachment hole 160.

The second pin mounting hole 160 has a boss 160a at the bottom. The boss 160a is fitted into a positioning hole 120e provided on the bottom surface of the second pin shaft portion 120a. The second pin 120 is positioned by attaching the second pin 120 so that the boss 160a fits into the positioning hole 120e. When the second pin 120 is fitted in the second groove 140, the second pin support portion 120 c is positioned so as to be positioned at the center in the width direction of the second groove 140.

The second pin mounting hole 160 has a screw hole 160b at the center of the bottom. The second pin 120 attached to the second pin attachment hole 160 is fixed to the fixed cylinder 20 by screwing the second pin fixing screw 162 into the screw hole 160b. The second pin fixing screw 162 is inserted into the hollow portion 120f of the second pin shaft portion 120a and screwed into the screw hole 160b. The second pin fixing screw 162 is an example of a fastening member.

<Operation of cam cylinder positioning and backlash removal mechanism>
[Positioning function]
When the lens barrel 10 is assembled, the first pin 110 is fitted into the first groove 130, and the second pin 120 is fitted into the second groove 140.

The width of the fitting portion 130b of the first groove 130 is narrower than the outer diameter of the first pin 110, and the width of the second groove 140 is smaller than the outer diameter of the second pin 120. For this reason, when the 1st pin 110 is made to fit in the fitting part 130b of the 1st groove | channel 130, the 1st pin 110 will press-contact the edge part 130c of the both sides of the fitting part 130b. Further, when the second pin 120 is fitted into the second groove 140, the outer peripheral surface of the second pin 120 presses and contacts the inner wall surfaces 140 a on both sides of the second groove 140. Thereby, the cam cylinder 30 is positioned on the optical axis Z with respect to the fixed cylinder 20.

[Function to remove backlash]
FIG. 25 is a diagram illustrating a fitting state between the first pin and the first groove.

As shown in the figure, when the first pin 110 is fitted in the first groove 130, the outer periphery of the first pin 110 is pressed against the edge 130 c of the fitting portion 130 b of the first groove 130. Thereby, the 1st pin 110 receives force F1 toward the inner side of radial direction from the edge part 130c. The force F1 acts as a radial force F1a and an axial force F1b on the first pin 110 because the outer shape of the first pin 110 is tapered. The radial force F1a acts as a force F1a that crushes the outer peripheral portion of the first pin 110. On the other hand, the axial force F1b acts as a force F1b that pushes the first pin 110 toward the fixed cylinder 20.

FIG. 26 is a diagram illustrating a fitting state between the second pin and the second groove.

As shown in the figure, when the second pin 120 is fitted into the second groove 140, the outer periphery of the second pin 120 is pressed against the inner wall surface 140a of the second groove 140. Since it abuts against the inner wall surface 140a of the second groove 140, the force F2 received by the second pin 120 is substantially only a radial force. That is, only the force for crushing the outer peripheral portion is obtained.

As described above, the first pin 110 receives the force F1b that is pushed toward the fixed cylinder 20. Since both the first pin 110 and the second pin 120 are elastically deformable, when the first pin 110 receives a force F <b> 1 b that is pushed toward the fixed cylinder 20, the fixed cylinder 20 is relative to the cam cylinder 30. Is energized in one direction. That is, the first pin 110 is biased in the direction in which it is pushed toward the fixed cylinder 20 (in the radial direction). As a result, the fixed cylinder 20 and the cam cylinder 30 are relatively displaced, and the play between them is removed. That is, the backlash is removed and the backlash is removed.

[Operation of interchangeable lens]
In the interchangeable lens 1 of the present embodiment configured as described above, the cam cylinder 30 rotates with respect to the fixed cylinder 20 by rotating the zoom ring 52. When the cam cylinder 30 rotates, the moving cylinder 40, the second lens holding frame LF2, the third lens holding frame LF3, and the fourth lens holding frame LF4 move along the optical axis Z by the action of the cam. As a result, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group G4 move along the optical axis Z, and the focal length changes. That is, it zooms.

The cam cylinder 30 is fitted to the fixed cylinder 20 and is rotatably held around the fixed cylinder 20, but the cam cylinder 30 and the fixed cylinder 20 have three pins (first pin 110 and second pin). 120) and the three grooves (the first groove 130 and the second groove 140), the play between them is removed. Thereby, generation | occurrence | production of an axis | shaft shift, a shaft fall, etc. can be prevented.

Further, since the mechanism for removing the backlash is constituted by a groove and a pin extending in a direction orthogonal to the optical axis Z, the cam cylinder 30 is not inhibited from rotating. Thereby, rotation of the cam cylinder 30 can be performed smoothly, and the operational feeling of the zoom ring 52 can be improved. Further, when the cam cylinder 30 is driven by a motor or the like, the drive can be stabilized and the drive can be controlled with high accuracy.

Also, since the pin slides in the groove, it is possible to prevent the generation of dust and noise.

Furthermore, since the mechanism for removing the backlash also has a positioning function, it is not necessary to provide a positioning mechanism separately. Thereby, the whole structure can be simplified.

[Modification]
<< First Pin Modification >>
FIG. 27 is a diagram illustrating another example of the first pin.

The first pin 110 shown in the figure has a frustoconical shape at the outer periphery. That is, the diameter of the outer peripheral portion is linearly reduced toward the tip. Thus, the 1st pin 110 should just have the taper shape which an outer diameter reduces toward a front-end | tip.

In addition, it can prevent that the 1st pin 110 fits into the 1st groove | channel 130 so that elastic deformation is impossible by setting it as an arc-shaped taper shape like the said embodiment. That is, the biting of the pin can be prevented.

Further, as shown in FIG. 27, the edge portion 130c of the wide portion 130a, which is a contact portion between the first pin 110 and the first groove 130, is not necessarily chamfered. When chamfered, the first pin 110 can be stably fitted to the first pin 110.

Further, the shape of the outer peripheral portion of the first pin 110, that is, the shape of the first pin outer peripheral portion 110b extends in the axial direction according to the depth of the first groove 130 to be fitted (the thickness of the cam cylinder 30). Alternatively, the shape may be a cylinder.

In the above embodiment, the first pin shaft portion 110a is fitted into the first pin mounting hole 150 provided in the fixed cylinder 20, and the first pin 110 is attached to the fixed cylinder 20. The structure for attaching 110 to the fixed cylinder 20 is not limited to this. In addition, for example, a convex portion is provided on the fixed cylinder 20 and a concave portion is provided on the bottom surface of the first pin shaft portion 110a, and the convex portion of the fixed cylinder 20 is fitted into the concave portion of the first pin shaft portion 110a. The first pin 110 may be attached to the fixed cylinder 20.

<< Modification of the second pin >>
The 2nd pin 120 should just be a shape which can be fitted in the 2nd groove | channel 140 in the state which the outer peripheral surface press-contacted to the inner wall surface 140a of the 2nd groove | channel 140. FIG. That is, for the second pin 120, a pin having a general shape can be adopted.

FIG. 28 is a diagram illustrating another example of the second pin.

The second pin 120 shown in the figure is a pin having a constant outer diameter. The second pin 120 of this configuration is fitted into the second groove 140 so that the outer peripheral surface thereof is in line contact with the inner wall surface 140 a of the second groove 140.

Further, the shape of the outer peripheral portion of the second pin 120, that is, the shape of the second pin outer peripheral portion 120b, extends in the axial direction according to the depth of the second groove 140 to be fitted (the thickness of the cam cylinder 30). Alternatively, the shape may be a cylinder.

In the above embodiment, the first pin shaft portion 120a is fitted in the second pin mounting hole 160 provided in the fixed cylinder 20, and the second pin 120 is mounted on the fixed cylinder 20. The structure for attaching 120 to the fixed cylinder 20 is not limited to this. In addition, for example, a convex portion is provided on the fixed cylinder 20, and a concave portion is provided on the bottom surface of the second pin shaft portion 120a, and the convex portion of the fixed cylinder 20 is fitted into the concave portion of the second pin shaft portion 120a. The first pin 120 may be attached to the fixed cylinder 20.

<Number of pins and layout>
In the above-described embodiment, the backlash between the fixed cylinder 20 and the cam cylinder 30 is removed using three pins and three grooves, but the number of pins and grooves is limited to this. It is not a thing. It can be composed of at least two pins and two grooves.

FIG. 29 is a cross-sectional view showing a structure of a mechanism for removing play between the fixed cylinder and the cam cylinder with two pins and two grooves.

One of the two pins is a first pin 110 and the other is a second pin 120. Similarly, one of the two grooves is a first groove 130 and the other is a second groove 140. The first pin 110 and the second pin 120 are disposed at positions facing each other. Thereby, the fixed cylinder 20 can be urged in one direction relative to the cam cylinder 30, and the play between the fixed cylinder 20 and the cam cylinder 30 can be removed.

Thus, the pin and the groove can be constituted by at least two pins each including at least the first pin and the second pin, and at least two grooves corresponding to the configuration of the pins.

It is preferable that the plurality of pins and grooves are arranged at equal intervals or close to equal intervals. Thereby, the cam cylinder 30 can be stably held with respect to the fixed cylinder 20.

《Groove function》
In the above embodiment, the cam cylinder 30 is positioned in the optical axis direction by the pin and the groove, but the rotatable range of the cam cylinder 30 may be regulated by the pin and the groove. Moreover, you may comprise so that both the functions may be implement | achieved.

When restricting the rotatable range of the cam cylinder 30 by the pin and the groove, the length of the groove is configured to correspond to the movable range of the cam cylinder 30. For example, when the rotatable range of the cam cylinder 30 is 60 °, the grooves are arranged in an angle range corresponding to 60 °. The cam cylinder 30 is restricted from rotating when the pin contacts the end of the groove.

<< Configuration of the first cylinder and the second cylinder >>
In the above embodiment, the first cylinder is the fixed cylinder 20 and the second cylinder is the cam cylinder 30, but the configurations of the first cylinder and the second cylinder are not limited to this. The present invention can also be applied to lens barrels having other configurations as long as they are relatively rotated.

<Application to other lens barrels>
In the above embodiment, the case where the present invention is applied to the lens barrel of the interchangeable lens of the interchangeable lens camera has been described as an example. However, the application of the present invention is not limited to this. The present invention can be similarly applied to a lens barrel of a lens apparatus incorporated in a so-called lens-integrated camera. The present invention can also be applied to lens barrels of optical devices other than cameras such as projectors, microscopes, telescopes, and binoculars.

In the above embodiment, the case where the present invention is applied to the lens barrel that moves the zoom lens group by the cam mechanism has been described as an example. However, the lens barrel that moves the focus lens group by the cam mechanism is described. Similarly, the present invention can be applied to.

Further, the means for rotating the cam cylinder (rotating cylinder) is not limited to manual operation but may be a motor.

DESCRIPTION OF SYMBOLS 1 Interchangeable lens 10 Lens barrel 12 Mount 20 Fixed cylinder 20A First rectilinear groove 20B Second rectilinear groove 20CD Common rectilinear groove 30 Cam cylinder 30A First cam groove 30B Second cam groove 30C Third cam groove 30D Fourth cam groove 40 Moving cylinder 50 Exterior cylinder 52 Zoom ring 54 Focus ring 60A 1st cam follower 60B 2nd cam follower 60C 3rd cam follower 60D 4th cam follower 110 1st pin 110a 1st pin axial part 110b 1st pin outer peripheral part 110c 1st pin support part 110d Recessed portion 110e Positioning hole 110f Hollow portion 120 Second pin 120a Second pin shaft portion 120b Second pin outer peripheral portion 120c Second pin support portion 120d Recessed portion 120e Positioning hole 120f Hollow portion 130 First groove 130a Wide portion 130b Fitting portion 130c Edge Part 140 second groove 140a inner wall surface 1 50 First pin mounting hole 150a Boss 150b Screw hole 152 First pin fixing screw 160 Second pin mounting hole 160a Boss 160b Screw hole 162 Second pin fixing screw G1 First lens group G2 Second lens group G2a Second lens Group front group G2b Second lens group Rear group G3 Third lens group G4 Fourth lens group G5 Fifth lens group GS Guide shaft LF1 First lens holding frame LF2 Second lens holding frame LF3 Third lens holding frame LF4 Fourth lens Holding frame LF5 Fifth lens holding frame SU Diaphragm unit St Diaphragm Z Optical axis F1 Force F1a received by the first pin F1b received by the first pin in the radial direction F1b Component force F2 received by the first pin in the axial direction F2 Power to receive

Claims (12)

A first cylinder and a second cylinder which are fitted and relatively rotatably held;
A plurality of elastically deformable pins provided at a plurality of locations of the first cylinder;
A plurality of grooves provided in a plurality of locations of the second cylinder and into which the plurality of pins are fitted, and a plurality of grooves extending in a direction perpendicular to the optical axis;
A lens barrel comprising:
The plurality of pins includes at least one first pin and at least one second pin,
The first pin has a tapered shape in which an outer diameter decreases radially outward with respect to the first cylinder and the second cylinder,
When the first pin is fitted into the groove, the outer peripheral surface of the first pin is pressed against the edge of the groove so that the first tube is radially inward with respect to the second tube. Energize
Lens barrel. The first pin has an arcuate taper shape in which an outer diameter decreases radially outward with respect to the first cylinder and the second cylinder.
The lens barrel according to claim 1. The second pin has a shape in which an outer peripheral surface swells in an arc shape toward the outside.
The lens barrel according to claim 1 or 2. The first pin is
A first pin shaft,
An annular or cylindrical first pin outer peripheral portion disposed concentrically with a gap between the first pin shaft portion,
A first pin support portion that supports the first pin outer peripheral portion with respect to the first pin shaft portion;
The lens barrel according to any one of claims 1 to 3, further comprising: The first pin is an integrally molded product made of resin, and is fixed to the first cylinder by a fastening member inserted coaxially.
The lens barrel according to claim 4. The second pin is
A second pin shaft,
An annular or cylindrical second pin outer peripheral portion disposed concentrically with a gap between the second pin shaft portion;
A second pin support portion for supporting the outer peripheral portion of the second pin with respect to the second pin shaft portion;
The lens barrel according to claim 1, comprising: The second pin is an integrally molded product made of resin, and is fixed to the first cylinder by a fastening member inserted coaxially.
The lens barrel according to claim 6. The groove into which the first pin is fitted has a chamfered edge;
The lens barrel according to any one of claims 1 to 7. Three pins are arranged at equal intervals in the first cylinder,
Of the three pins, one is composed of the first pin and the rest is composed of the second pin.
The lens barrel according to any one of claims 1 to 8. The pin is fitted into the groove to position the second cylinder relative to the first cylinder in the optical axis direction, and / or relative to the second cylinder relative to the first cylinder. Restrict the range of rotation,
The lens barrel according to any one of claims 1 to 9. The second cylinder is fitted to the outer periphery of the fixed first cylinder, and the outer periphery of the first cylinder is rotatably held.
The lens barrel according to any one of claims 1 to 10. The first cylinder is a fixed cylinder having a rectilinear groove;
The second cylinder is a cam cylinder provided with a cam groove;
The lens barrel according to claim 11.

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