JP4855977B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel that moves a lens in the optical axis direction, and more particularly to a lens barrel that includes a cam groove and a follower pin.

Conventional lens barrels include a fixed cylinder having a cam groove on the inner peripheral surface, a rotary cylinder having a follower pin inserted into the cam groove of the fixed cylinder on the outer peripheral surface and a cam groove on the inner peripheral surface, and a cam groove of the rotary cylinder. The outer cylinder has a follower pin to be inserted in the outer peripheral surface and a lens barrel that holds the lens on the inner side, and the rotating barrel is rotated and extended in the optical axis direction, and the lens barrel is moved in the optical axis direction by the cam action of the rotating barrel. There are known ones that extend and move the lens in the optical axis direction (see, for example, Patent Document 1 and Patent Document 2).
In this lens barrel, the cam groove is formed in a substantially V-shape (inclined surface) whose cross section spreads outward, and the follower pin is formed in a tapered conical shape corresponding to the cam groove. Then, when the follower pin of the lens cylinder is inserted in the cam groove of the rotary cylinder, when the rotary cylinder is rotated in one direction or in the opposite direction, the follower pin receives a cam action in the optical axis direction, and the lens cylinder becomes the optical axis. It is designed to extend or retract in the direction.

  By the way, in a camera or the like equipped with such a lens barrel, particularly in a state in which the lens barrel is extended (particularly in a state in which the follower pin is located in a region where the cam groove faces in a direction substantially perpendicular to the optical axis direction). When the user drops the camera or causes the tip of the lens barrel to collide with another object and an external force is applied that pushes the lens barrel, the lens barrel follower pin falls out of the cam groove of the rotating barrel and becomes inoperable. There was a risk of becoming.

To deal with this, simply deepening the cam groove and lengthening the insertion margin of the follower pin leads to an increase in the diameter of the rotating cylinder and an increase in the size of the entire lens barrel, and an increase in frictional resistance (driving load) There is a possibility that smooth operation of feeding and feeding cannot be obtained.
In particular, when a rotating cylinder having a cam groove on the inner peripheral surface is molded from a resin material, it is necessary to provide a mold draft that defines the cam groove due to molding restrictions. It still has to be formed in a substantially V shape with an inclined surface.

JP 2003-057705 A JP 2004-361519 A

  The present invention has been made in view of the above-described prior art, and an object of the present invention is to simplify the structure, reduce the diameter, reduce the size, etc. of a lens barrel having a follower pin and a cam groove. On the other hand, it is an object of the present invention to provide a lens barrel that can prevent the follower pin from falling off from the cam groove and can obtain a smooth feeding and retraction operation.

The lens barrel of the present invention includes a cam cylinder having a cam groove having a substantially V-shaped cross section defined by an inclined surface on an inner peripheral surface, a substantially conical tip portion that is inserted into the cam groove and slides, and A follower pin defined by a cylindrical portion formed in contact with the cam groove in a non-contact manner is provided following the tip portion, and a lens barrel that holds the lens is provided, and the lens barrel moves relative to the cam barrel in the optical axis direction. The cam barrel is provided with a cam block that defines an upright surface facing the cylindrical portion of the follower pin from the rear in the optical axis direction in a predetermined region along the cam groove. The block is characterized in that it is fitted into a recess formed so as to cut out a part of an inclined surface defining a cam groove on the inner peripheral surface of the cam cylinder.
According to this configuration, in a predetermined region along the cam groove, the upright surface (a flat surface or a cylindrical curved surface facing in parallel with the outer peripheral surface of the cylindrical portion) facing the cylindrical portion of the follower pin from the rear in the optical axis direction. When the lens cylinder is extended from the cam cylinder and an external force that pushes the lens cylinder toward the rear in the optical axis direction is applied, the follower pin cylinder part stands upright on the cam block. It is regulated by the surface to prevent its falling out. Thus, it is possible to prevent the follower pin from falling out of the cam groove with a simple structure.
Further, since the cam groove has a substantially V-shaped cross section defined by the inclined surface, it is possible to easily form the cam cylinder by forming a draft angle when molding the cam cylinder, and to provide a cylindrical portion of the follower pin. Is formed so as not to be in contact with the cam groove, the frictional force can be reduced at least in the cam region other than the cam block, and smooth operation is possible.
Further, since the cam block is fitted in a recess formed on the inner peripheral surface of the cam cylinder, the cam cylinder can be reduced in diameter, and a desired position along the cam groove can be achieved by appropriately selecting a place where the recess is provided. The cam block can be provided at the position, and the follower pin can be prevented from falling off due to an impact or the like.

In the above-described configuration, the cam block may be configured so as to be opposed to the cylindrical portion with a predetermined gap.
According to this configuration, since the cam block (the upright surface thereof) faces the cylindrical portion of the follower pin with a predetermined gap, the cylindrical portion and the cam block are not in contact with each other in a normal operation where no impact force is received. When the tip of the follower pin is guided by the cam groove and receives an impact force that pushes in from the outside, the cylindrical portion is regulated so as not to come into contact with the cam block (an upright surface thereof) and fall off. This makes it possible to smoothly perform normal feeding and retraction operations and to reliably prevent the follower pins from falling off when receiving an impact force or the like from the outside.

In the above-described configuration, a configuration in which the predetermined region is a region in which the cam groove faces in a direction substantially perpendicular to the optical axis direction can be employed.
According to this configuration, when the follower pin is in a region facing in a direction substantially perpendicular to the optical axis direction, when receiving an impact force that pushes the lens tube, the follower pin is pushed in a direction perpendicular to the cam groove path. Therefore, it is in a state where it easily falls off. Therefore, by providing a cam block in this region, it is possible to reliably prevent the follower pin from falling off.

In the above-described configuration, a configuration in which the predetermined region is a region where the lens tube is positioned at the maximum extension position with respect to the cam tube can be employed.
According to this configuration, when the lens barrel is in the most extended state, the follower pin can be reliably prevented from falling off even if an impact force that pushes the lens barrel is applied.

  According to the lens barrel having the above-described configuration, the follower pin can be cammed even if it receives impact force from the outside while achieving a simplified structure, a small diameter, a small size, etc. in a lens barrel having a follower pin and a cam groove. It is possible to prevent detachment (drop off) from the groove, and a smooth feeding operation and a feeding operation can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
1 to 8 show an embodiment of a lens driving device including a lens barrel according to the present invention. FIG. 1 is a front view of the device, and FIGS. 2 to 5 are retracted positions and wide angles of the lens barrel. FIG. 6 is a development view of the cam barrel included in the lens barrel, and FIGS. 7 and 8 are enlarged views of the cam barrel, the cam block, and the follower pin. It is the partial perspective view and partial sectional view which were shown.

  As shown in FIGS. 1 to 5, this lens driving device is rotated inside a base 10 to which an image pickup element PE such as a filter plate FP and a CCD is attached, a fixed cylinder 20 fixed to the base 10, and the inside of the fixed cylinder 20. And the cam cylinder 30 supported so as to be linearly movable, the key cylinder 40 fitted inside the cam cylinder 30 and restricted so as not to rotate, the cam cylinder 30 and the key cylinder 40 being supported so as to be movable in the optical axis direction L. The first lens barrel 50 and the second lens barrel 60, the lens barrel 70 supported so as to be movable in the optical axis direction L with respect to the first lens barrel 50, the drive mechanism 80 for driving the cam barrel 30, and the lens barrel 70 A driving mechanism 90 for driving the motor.

  The base 10 is formed of a resin material, and as shown in FIGS. 1 to 5, an opening 11 through which light passes, a recess 12 formed behind the opening 11 to attach the filter plate FP and the image sensor PE, 13 and a holding portion 14 for holding the drive mechanism 80 and the like.

  The fixed cylinder 20 is formed into a cylindrical shape having an axis parallel to the optical axis direction L by using a resin material, and as shown in FIGS. A notch portion 21 cut out into three sides, three cam grooves 22 formed on the inner peripheral surface to exert a cam action on the cam cylinder 30 (follower pin 31 described later), and a key cylinder 40 (projection 41 described later). A guide groove 23 and the like for guiding only in the optical axis direction L are formed.

  The three cam grooves 22 have a predetermined amount from the retracted position (position shown in FIG. 2) corresponding to the position where the cam cylinder 30 is most retracted when zooming from the wide-angle end → the intermediate position → the telephoto end. The cam cylinder 30 is placed at the same position in the optical axis direction L without exerting a cam action from the wide angle end to the telephoto end. The cam cylinder 30 is positioned so that only rotation is performed.

  The cam cylinder 30 is molded into a cylindrical shape having an axis parallel to the optical axis direction L using a resin material, and is inserted into the cam groove 22 of the fixed cylinder 20 on the outer peripheral surface thereof as shown in FIGS. It includes three follower pins 31 provided at equal intervals (120 degree intervals) as much as possible, and a tooth row (arc-shaped rack portion) 32 formed on the rear end side so as to mesh with a gear 81 described later, and its inner peripheral surface 30a. 3, three cam grooves 33 into which follower pins 51 of the first lens cylinder 50 described later are inserted, three cam grooves 34 into which follower pins 61 of the second lens cylinder 60 described later are inserted, and latching claws 44 of the key cylinder 40 described later. Is formed to include an annular groove 35 formed on the front end side, three recesses 36 formed in a substantially rectangular shape on the inner peripheral surface, three cam blocks 37 fitted in the recess 36, and the like. ing.

6 to 8, the three cam grooves 33 have a substantially V-shaped cross section on the inner peripheral surface 30a, that is, the groove bottom 33a and a tip 51a of a follower pin 51 described later slide. The inclined surfaces 33b and 33c are formed so as to delimit. Here, the inclined surface 33b is positioned on the front side F in the optical axis direction L with respect to the groove bottom 33a, and the inclined surface 33c is positioned on the rear side R of the optical axis direction L with respect to the groove bottom 33a.
In the zooming from the wide-angle end → the intermediate position → the telephoto end, the three cam grooves 33 first move the first lens barrel 50 relative to the cam barrel 30 in the optical axis direction L as shown in FIG. It is positioned at the wide-angle end (position shown in FIG. 3) that extends most forward F in the optical axis direction L from the retracted position (position shown in FIG. 2) corresponding to the retracted position, and then rearward in the optical axis direction L by a predetermined amount. Positioned at an intermediate position (position shown in FIG. 4) retracted to R, and then, a cam action is performed to position the telephoto end (position shown in FIG. 5) forwarded forward F in the optical axis direction L by a predetermined amount. Is formed.

  The three cam grooves 34 are formed so as to have a substantially V-shaped cross section on the inner peripheral surface 30a. During zooming from the wide-angle end → the intermediate position → the telephoto end, as shown in FIG. First, a wide angle end (FIG. 3) in which a predetermined amount is retracted from the retracted position (the position shown in FIG. 2) corresponding to the most retracted position in the optical axis direction L to the cam cylinder 30. The telephoto end is positioned at an intermediate position (position shown in FIG. 4) that is forwarded forward in the optical axis direction L by a predetermined amount, and is subsequently forwarded forward in the optical axis direction L by a predetermined amount. It is formed so as to exert a cam action to be positioned at (position shown in FIG. 5).

As shown in FIGS. 6 and 7, the three concave portions 36 are formed in a substantially rectangular shape so as to cut out a part of the inclined surface 33 c in a predetermined region along the cam groove 33 of the inner peripheral surface 30 a. A cylindrical fitting protrusion 36 a that is fitted into a fitting hole 37 a of a cam block 37 described later is formed at the approximate center of the recess 36.
Here, the predetermined region in which the recess 36 is formed corresponds to a region where the cam groove 33 faces in a direction substantially perpendicular to the optical axis direction L, and as shown in FIGS. 3 and 6, the first lens. This corresponds to an area where the tube 50 is positioned at the maximum extended position where the cylinder 50 is extended most forward F toward the front F in the optical axis direction L.

As shown in FIGS. 6 and 7, the three cam blocks 37 are formed using metal materials so as to be fitted into the respective recesses 36, and are arranged in the optical axis direction L on a cylindrical portion 51 b of a follower pin 51 to be described later. Are formed so as to include an upright surface 37a facing from behind, a fitting hole 37b for fitting the fitting projection 36a, and the like. The cam block 37 may be fixed to the recess 36 using an adhesive or the like.
The upright surface 37a of the cam block 37 is in the optical axis direction L with respect to a cylindrical portion 51b (the outer peripheral surface) of the follower pin 51, which will be described later, as shown in FIG. 8B when the follower pin 51 is closest. It arrange | positions so that it may oppose with a predetermined clearance from back.

Thus, since the cam block 37 is fitted in the recess 36 formed so as to cut out a part of the inclined surface 33c that defines the cam groove 33 on the inner peripheral surface 30a of the cam cylinder 30, the cam cylinder The cam block 37 can be provided at a desired position along the cam groove 33 by appropriately selecting a place where the concave portion 36 is provided.
Further, since the cam block 37 (the upright surface 37a) faces the cylindrical portion 51b (the outer peripheral surface thereof) of the follower pin 51 with a predetermined gap, in the normal operation not receiving impact force, the cam block 37b and the cam portion 51b When the tip 51a of the follower pin 51 is guided by the cam groove 33 in a non-contact state with the block 37 and receives an impact force that pushes in from the outside, the cylindrical portion 51b contacts the cam block 37 (the upright surface 37a). It is regulated so that it does not fall out in contact. As a result, normal feeding and retraction operations can be performed smoothly, and the follower pin 51 can be reliably prevented from falling off when receiving an impact force or the like from the outside.

  In particular, the cam block 37 has a region in which the cam groove 33 faces in a direction substantially perpendicular to the optical axis direction L on the path of the cam groove 33 (and the first lens cylinder 50 faces the front F in the optical axis direction L). Is located in the region where the follower pin 51 cannot easily escape (moves along the cam groove 33) even if it receives an external force. Even when an impact force that pushes in one lens barrel 50 is applied, the follower pin 51 can be reliably prevented from falling off.

  The key cylinder 40 is molded into a cylindrical shape having a central axis parallel to the optical axis direction L using a resin material, and is inserted into the guide groove 23 of the fixed cylinder 20 at the rear end as shown in FIGS. Projection 41, three guide grooves 42 for receiving and fixing a convex fixing portion 52 for fitting and fixing a follower pin 51 to be described later and guiding in the optical axis direction L, and a fixing portion for fitting and fixing a follower pin 61 to be described later Three guide grooves 43 that receive 62 and guide it in the optical axis direction L, and latching claws 44 inserted into the annular groove 35 of the rotating cylinder 30 on the outer peripheral surface thereof are formed.

  The key cylinder 40 is inserted into the cam cylinder 30 in a nested manner, the latching claw 44 is inserted into the annular groove 35 of the cam cylinder 30, and the protrusion 41 is inserted into the guide groove 23 of the fixed cylinder 20. The rotation of the first lens barrel 50 is held by the fixed barrel 20 so as to be unrotatable and allowed to rotate, and moves in the optical axis direction L together with the cam barrel 30. The movement in the optical axis direction L is allowed while being restricted, and the movement in the optical axis direction L is allowed while restricting the rotation of the second lens cylinder 60 by the guide groove 43.

  The first lens cylinder 50 is molded into a cylindrical shape having a shaft center parallel to the optical axis direction L using a resin material, and the cam groove 33 of the cam cylinder 30 is formed on the outer peripheral surface thereof as shown in FIGS. The three follower pins 51 provided at equal intervals (120 degree intervals) to be inserted into the key tube 40, and the convex fixing that is inserted into the guide groove 42 of the key cylinder 40 protruding in a convex shape so as to be fitted and fixed. A central cylindrical portion 53 that reciprocally supports the lens barrel 70 in the optical axis direction L, an opening 54 that allows the lens barrel 70 to freely move in and out, and the like.

As shown in FIGS. 8A and 8B, the three follower pins 51 are inserted into the cam grooves 33 (inclined surfaces 33b and 33c) using a metal material and slide in a substantially conical tip 51a. The cylindrical part 51b formed following the tip part 51a is defined.
In the area where the cam block 37 is not provided, the follower pin 51 slides with only the tip 51a contacting the cam groove 33 (inclined surfaces 33b and 33c), as shown in FIG. In the region where the cam block 37 is provided, as shown in FIG. 8 (b), only the tip 51a slides in contact with part of the cam groove 33 (part of the inclined surface 33b and inclined surface 33c). In addition, the cylindrical portion 51b is opposed to the upright surface 37a of the cam block 37 with a predetermined gap.
The first lens cylinder 50 moves in the optical axis direction L along the profile (path) of the cam groove 33 by the cam groove 33 exerting a cam action on the follower pin 51 as the cam cylinder 30 rotates. It has become.

  The lens barrel 70 is molded using a resin material, and is inserted into the central cylindrical portion 53 of the first lens barrel 50 and holds the lens G1, as shown in FIGS. 2 to 5, and the cylindrical portion 71. It is formed so as to include a connecting portion 72 and the like extending from the connecting mechanism and connected to a driving mechanism 90 described later. The lens barrel 70 is moved relative to the first lens barrel 50 in the optical axis direction L by a driving force of a driving mechanism 90 described later.

The second lens cylinder 60 is molded into a cylindrical shape having an axis parallel to the optical axis direction L using a resin material, and the cam groove 34 of the cam cylinder 30 is formed on the outer peripheral surface thereof as shown in FIGS. The three follower pins 61 and the follower pins 61 provided at equal intervals (120 degree intervals) to be inserted into and fixed to each other, and the fixing portion 62 inserted into the guide groove 43 of the key tube 40 and the lens G2 are held. The shutter mechanism S is integrally held behind the lens G2.
The second lens cylinder 60 is configured such that when the cam cylinder 30 rotates, the cam groove 34 exerts a cam action on the follower pin 61 and moves in the optical axis direction L along the profile (path) of the cam groove 34. It has become.

  As shown in FIGS. 1 and 2, the drive mechanism 80 includes a gear 81 that meshes with the tooth row 32 of the cam cylinder 30, a reduction gear (not shown) that meshes with the gear 81, a motor 82 that is fixed to the base 10, and the like. Is formed. When the motor 82 rotates, the cam cylinder 30 is rotated relative to the fixed cylinder 20 via the reduction gear and the gear 81.

The driving mechanism 90 is housed inside the first lens cylinder 50 so as to move together with the first lens cylinder 50 in the optical axis direction L as shown in FIGS. Formed by a nut 91 held by the portion 72, a lead screw 92 screwed into the nut 91, a driven gear 93 formed integrally with the lead screw 92, a motor (not shown) that exerts a rotational driving force on the driven gear 93, and the like. Has been.
That is, when the lead screw 92 is rotated via the driven gear 93 by the rotational driving force of the motor, the lens barrel 70 moves in the optical axis direction L together with the nut 91 with respect to the first lens barrel 50. ing.

Next, the operation of the above apparatus will be described.
First, in the retracted state, as shown in FIG. 2, the first lens barrel 50, the second lens barrel 60, and the cam barrel 30 are in the most retracted position toward the rear in the optical axis direction L.
When the drive mechanism 80 generates a rotational driving force in one direction from this retracted state, the follower pin 31 receives the cam action of the cam groove 21, and the cam barrel 30 is rotated toward the front F in the optical axis direction L. .

Further, due to the rotation of the cam cylinder 30, the follower pins 51 and 61 receive the cam action of the cam grooves 33 and 34, respectively, and the first lens cylinder 50 and the second lens cylinder 60 are extended forward F in the optical axis direction L, It reaches the wide-angle end (photographing position) shown in FIG.
Subsequently, when the driving mechanism 80 generates a rotational driving force in the same direction, the cam cylinder 30 does not move in the optical axis direction L but rotates at a predetermined position, and the follower pins 51 and 62 are cams of the cam grooves 33 and 34, respectively. Under the action, the first lens cylinder 50 further extends forward F in the optical axis direction L, and the second lens cylinder 60 retracts by a predetermined amount rearward in the optical axis direction L. To the position.

  Further, when the drive mechanism 80 generates a rotational driving force in the same direction, the cam cylinder 30 does not move in the optical axis direction L but rotates at a predetermined position, and the follower pins 51 and 62 are respectively connected to the cam grooves 33 and 34. Upon receiving the cam action, the first lens cylinder 50 is retracted by a predetermined amount toward the rear R in the optical axis direction L, and the second lens cylinder 60 is extended by a predetermined amount toward the front F in the optical axis direction L. FIG. To the telephoto end (photographing position).

In addition, the driving mechanism 90 appropriately generates a driving force, and the lens barrel 70 moves in the optical axis direction L relative to the first lens barrel 50.
On the other hand, when the driving mechanism 80 generates a reverse rotational driving force, the telephoto end (photographing position) shown in FIG. 5 → the intermediate (photographing) position shown in FIG. 4 → the wide-angle end (photographing position) shown in FIG. The retracted position shown in FIG. 2 is reached.

As shown in FIG. 8B, the upright surface 37a of the cam block 37 at the wide-angle end (photographing position) where the first lens cylinder 50 is most advanced to the front F in the optical axis direction L in the above-described extending and retracting operations. However, the first lens barrel 50 is directed toward the rear F in the optical axis direction L due to dropping or the like because it is opposed to the cylindrical portion 51b of the follower pin 51 with a predetermined gap from the rear in the optical axis direction L. Even if an impact force (external force) that pushes in is applied, the movement of the cylindrical portion 51 b of the follower pin 51 is restricted by the upright surface 37 a of the cam block 37, and the falling off from the cam groove 33 is prevented.
As described above, according to the lens barrel, the follower pin 51 can be prevented from falling off from the cam groove 33 while the structure is simplified, the diameter is reduced, the size is reduced, and the feeding and the feeding operation are smoothly performed. Can be done.

In the above embodiment, as a predetermined region of the cam groove 33 where the cam block 37 is provided, a region where the first lens cylinder 50 is positioned at the wide angle end (a region where the cam groove 33 faces in a direction substantially perpendicular to the optical axis direction L). However, the present invention is not limited to this. As shown in FIGS. 9 and 10, the region where the first lens barrel 50 is positioned at the intermediate position (the cam groove 33 is located in the optical axis direction L). Region that faces in a substantially vertical direction), or a region in which the first lens barrel 50 is positioned at the telephoto end may be applied as shown in FIGS.
In this case, the cam block 37 ′ disposed in the region shown in FIGS. 9 and 10 is substantially flat in which the upright surface 37 a ′ facing the cylindrical portion 51 b of the follower pin 51 extends in a direction substantially perpendicular to the optical axis direction L. The cam block 37 ″ formed so as to form a surface and disposed in the region shown in FIGS. 11 and 12 has an upright surface 37 a ″ facing the cylindrical portion 51 b of the follower pin 51 along the path of the cam groove 33. It is formed so as to form a substantially flat surface extending in the direction.

  As described above, the lens barrel of the present invention can prevent the follower pin from falling off from the cam groove while achieving a simplified structure, a reduced diameter, a reduced size, etc., and allows a smooth extension and retraction operation. Therefore, as long as it can be applied to a portable digital camera or the like, it can be applied to a silver salt camera and other lens optical devices as long as it receives an impact force by dropping or the like.

1 is a front view showing an embodiment of a lens driving device including a lens barrel according to the present invention. It is sectional drawing of the apparatus which shows the state which has a lens barrel in a retracted position. It is sectional drawing of the apparatus which shows the state which has a lens barrel in a wide angle end. It is sectional drawing of the apparatus which shows the state which has a lens barrel in an intermediate position. It is sectional drawing of an apparatus which shows the state which has a lens barrel in a telephoto end. It is an expanded view which shows the internal peripheral surface of the cam cylinder contained in a lens barrel. It is a perspective view which shows the cam block provided in a cam cylinder. (A) is a partial sectional view showing the relationship between the follower pin of the first lens barrel and the cam groove of the cam barrel, and (b) is a portion showing the relationship between the follower pin of the first lens barrel, the cam groove of the cam barrel and the cam block. It is sectional drawing. It is sectional drawing which shows other embodiment of a lens barrel. FIG. 10 is a development view showing an inner peripheral surface of a cam cylinder included in the lens barrel shown in FIG. 9. It is sectional drawing which shows other embodiment of a lens barrel. FIG. 12 is a development view showing an inner peripheral surface of a cam cylinder included in the lens barrel shown in FIG. 11.

Explanation of symbols

L optical axis direction 10 base 20 fixed cylinder 22 cam groove 23 guide groove 30 cam cylinder 31 follower pin 32 tooth row 33, 34 cam groove 33a groove bottom 33b, 33c inclined surface 35 annular groove 36 recess 36a fitting protrusions 37, 37 ', 37 ″ Cam block 37a, 37a ′, 37a ″ Upright surface 37b Fitting hole 40 Key tube 41 Protrusion 42, 43 Guide groove 44 Latching claw 50 First lens tube 51 Follower pin 51a Tip 51b Column 52 Fixed to convex Part 53 Central cylindrical part 54 Opening part 60 Second lens cylinder 61 Follower pin 62 Fixing part 63 Cylindrical part G1 Lens 70 Lens cylinder 71 Cylindrical part G1 Lens 72 Connection part 80 Drive mechanism 81 Gear 82 Motor 90 Drive mechanism 91 Nut 92 Lead screw 93 Driven gear

Claims (4)

A cam cylinder having a cam groove having a substantially V-shaped cross section defined by the inclined surface on the inner peripheral surface, said with following the are inserted into the cam groove substantially conical tip and the tip slides A lens barrel having a lens barrel having a follower pin defined by a cylindrical portion formed in a cam groove in a non-contact manner and holding a lens, wherein the lens barrel moves relative to the cam barrel in the optical axis direction. Because
The cam cylinder is provided with a cam block that defines an upright surface facing the cylindrical portion of the follower pin from the rear in the optical axis direction in a predetermined region along the cam groove,
The cam block is fitted in a concave portion formed so as to cut out a part of an inclined surface defining the cam groove on the inner peripheral surface of the cam cylinder.
A lens barrel characterized by that. The cam block is disposed so as to face the cylindrical portion with a predetermined gap.
The lens barrel according to claim 1. The predetermined region is a region in which the cam groove faces in a direction substantially perpendicular to the optical axis direction.
The lens barrel according to claim 1, wherein the lens barrel is provided. The predetermined area is an area for positioning the lens cylinder at a maximum extension position with respect to the cam cylinder.
The lens barrel according to claim 1, wherein the lens barrel is provided.

Images