JP2002277714A - Extending structure for zoom lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens barrel capable of securing sufficient stroke so as to drive to open/close a barrier by enhancing rigidity in a multistage zoom lens barrel. SOLUTION: In this zoom lens barrel provided with a multistage extending lens barrel, a helicoid idle rotation area 25b1 mentioned later is formed at the female holicoid 25b of a 2nd straight advance guiding ring 25 helicoid- coupled with the male helicoid 30a of a 3rd outside appearance barrel 30 with which a 4th outside appearance barrel 31 is coupled at a leading end in the fixed barrel 12 of a camera body, and the area 25b1 is an area where the lens barrel is not extended even though the barrel 30 is rotated from the housing position of the zoom lens barrel to a photographing feasible shortest extending position. The lens barrel is provided with the area 25b1, and a groove 25e in a peripheral direction is formed along the respective opposite thrust surfaces 25b2 and 25b2 of the area 25b1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extension structure of a multi-stage zoom lens barrel having a barrier.

[0002]

2. Description of the Related Art In recent years, zoom lenses of cameras are required to be reduced in size and increased in magnification. For this purpose, the lens barrel is multi-staged. When multi-stage lens barrels are used, a helicoid feeding structure or a cam feeding structure is used as a structure for connecting the relatively moving lens barrels.
It is known that the cam extension structure has a high degree of freedom in setting the amount of extension with respect to the rotation angle of the lens barrel and a high degree of freedom in how to extend, but it is known that securing the rigidity of the lens barrel and blocking light are difficult.
On the other hand, in the helicoid extension structure, although the extension amount with respect to the rotation angle of the lens barrel is constant, it is known that securing of the rigidity of the lens barrel and light shielding are easy. Therefore, a helicoid extension structure is suitable for a multistage lens barrel. The opening and closing of the barrier provided at the tip of the lens barrel utilizes the relative movement between the tip barrel on which the barrier is mounted and the next-stage barrel. However, when the number of stages of the lens barrel increases, the relative movement amount of each lens barrel decreases, and it becomes difficult to secure a stroke for opening and closing the barrier. In particular, in the case of a so-called wide zoom lens, since the entire length of the optical system at the wide end is short, the extension amount from the lens barrel, the entire length of the optical system, and the shortest storage position to the wide end is reduced. When a helicoid structure is used to solve this problem, the sizes of the individual leads are approximated to effectively utilize the length of the extension barrel, and the extension amounts are nearly equal. Therefore, a stroke required for opening and closing the barrier cannot be secured.

In order to solve this problem, the stroke can be secured if only the most advanced lens barrel is provided with a cam extension structure and the other lens barrels are extended at a short rotation angle so as not to extend much. However, in this case, the lead for extending the state-of-the-art lens barrel in the opening and closing area of the barrier becomes extremely large, and the resistance at the time of retracting the lens barrel in the storage direction becomes too large, resulting in insufficient strength and the like. Is generated. Further, if the leading end lens barrel alone is largely extended, there arises a problem that a flexible printed circuit board connecting a shutter block mounted on the leading end lens barrel and a circuit board in the body is stretched.

Another solution is to extend a plurality of lens barrels connected to the state-of-the-art lens barrel by using a cam extension structure to reduce the amount of extension even when the lens barrel rotates, or to rotate the lens barrel. If a section is not provided, a stroke for opening and closing the barrier can be secured while ensuring a rotation angle from the storage to the wide end. However, it is difficult for such a cam structure to secure the rigidity of the lens barrel. Moreover,
If an idle section that does not extend even when rotated by the helicoid extension structure is to be provided, the position in the optical axis direction must be regulated even if the idle section is not extended, so that it is difficult to process the idle section.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to increase the rigidity of a multi-stage zoom lens barrel and to obtain a zoom lens barrel capable of securing a sufficient stroke for driving a barrier to open and close.

[0006]

SUMMARY OF THE INVENTION The present invention, which achieves this object, is a zoom lens barrel having a multi-stage extending barrel, wherein the most advanced barrel is connected from a barrel connected to a fixed portion of a camera body. Each lens barrel up to the cylinder is connected by a helicoid extension structure, the most advanced lens barrel and the subsequent lens barrel are connected by a cam extension structure, and the helicoid extension structure that connects the latter lens barrel with another lens barrel is A helicoid idling region that does not extend even when rotated between the retracted position of the zoom lens barrel and the photographable shortest extending position, and a helicoid extension structure having the helicoid idling region is a female member formed in one barrel. A helicoid comprising: a helicoid; and a male helicoid formed in the other lens barrel, wherein the one lens barrel and the other lens barrel are allowed to rotate in the circumferential direction when the male helicoid is in the storage position. Rolling to form a region on the female helicoid, characterized in that along each thrust surface against the said helicoid idling region to form circumferential grooves. The present invention is particularly useful for a helicoid feeding structure having a helicoid ring formed by injection molding of a synthetic resin using a mold. Further, the present invention is applicable to a pair of lens barrels connected by a helicoid extension structure. In this case, the helicoid extension structure includes a helicoid idling region that does not extend even when rotated, and includes a helicoid idling region. Has a female helicoid formed in one lens barrel and a male helicoid formed in the other lens barrel, and the male helicoid is formed when the one lens barrel and the other lens barrel are at specific positions. A helicoid idling region that allows circumferential rotation of the helicoid is formed in the female helicoid, and a circumferential groove is formed along each opposing thrust surface in the helicoid idling region of the female helicoid.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. This embodiment is an embodiment in which the present invention is applied to a retractable four-stage zoom lens barrel.

The zoom lens barrel is a collapsible four-stage barrel as shown in FIGS. 1 to 5, and includes a fixed barrel 12 fixed to the camera body and an optical axis supported by the fixed barrel 12 along the optical axis. The first appearance tube 17, the second appearance tube 23, and the third appearance tube (cam ring) 30 as a four-stage extension barrel that relatively moves forward and backward.
And a fourth external cylinder (lens support cylinder) 31.
In this zoom lens barrel, a first exterior barrel 17 is provided for the fixed barrel 12 and a second exterior barrel 2 is provided for the first exterior barrel 17.
The third external cylinder 30 is connected to the second external cylinder 23 by a helicoid extension structure. The fourth external cylinder 31 is connected to the third external cylinder by a cam structure. In the present embodiment, the first external cylinder 1
7 and the second external appearance tube 23 are formed separately from a helicoid ring having a helicoid, and the first external appearance is provided at a position further extended (disassembly / assembly position) from the tele end position where the zoom lens barrel is normally extended most. The tube 17 and the second external tube 23 are formed to be detachable. In this embodiment, when the camera is rotated by 8 degrees from the telephoto end position, it reaches the disassembly / assembly position. The lens barriers 92 and 93 attached to the distal end of the fourth external cylinder 31 are the fourth external cylinder 3.
The first and third external cylinders 30 are driven to open and close by relative movement in the direction of the optical axis between the storage position and the shortest feed-out position (in this embodiment, the wide end position) at which photographing is possible. Further, the zoom lens barrel according to the present embodiment has a helicoid extension structure for moving the second external appearance tube 23 and the third external appearance tube 30, and the second external appearance tube 23 and the third external appearance tube 30 between the storage position and the wide position. Is provided, but an idle rotation section is provided which does not move in the optical axis direction. That is, in the present embodiment, the second appearance tube 23 and the third appearance tube 30 rotate at the same speed during the extension from the stowed state toward the wide position direction, but have an idle section in which the relative movement in the optical axis direction is not performed. In this idle section, the first external cylinder 17 rotates and moves in the optical axis direction, and the fourth external cylinder 31 does not rotate and the third external cylinder 30 does not rotate.
Moves in the optical axis direction relative to
The barriers 92 and 93 are driven to open and close by the relative movement of the third external cylinder 30 in the optical axis direction.

A more detailed overall structure of the zoom lens barrel will be described first with reference to FIGS. FIG. 1 is an exploded perspective view showing the main part of the zoom lens barrel. In this specification, the subject side is referred to as a front side, and the camera body (film) side is referred to as a rear side.

A fixed cylinder 12 fixed to a camera body 11
Has a female helicoid 12a formed on its inner peripheral surface. The female helicoid 12a has a first helicoid ring 1
The male helicoid 14a formed on the outer periphery of No. 4 is screwed. On the other hand, a pinion 16 that is driven to rotate by a zooming motor 15 is located outside the fixed cylinder 12, and a part of the male helicoid 14a is cut off from the pinion 16, and the male helicoid 14a on both sides of the cut portion is cut off. The gear 14b formed on the outer periphery of the first helicoid ring 14 meshes with the gear 14b. A first external cylinder 17 is connected to a front portion of the first helicoid ring 14.

First helicoid ring 14 and first external cylinder 17
Is the connecting portion 1 formed at the front end of the first helicoid ring 14.
41 and the joint 1 formed at the rear end of the first external cylinder 17
By the engagement of 71, they are coupled so as to rotate integrally.
A first linear guide ring 18 that can rotate relative to the first external cylinder 17 and moves together in the optical axis direction (cannot move relative to the optical axis direction) is supported in the first external cylinder 17. Have been. The first rectilinear guide ring 18 allows only the rectilinear movement (advance / retreat) in the optical axis direction without rotating with respect to the fixed cylinder 12 by the rectilinear guide projection 18a engaging with the rectilinear guide groove 12b of the fixed cylinder 12. , Are supported by the first external cylinder 17.

The first external cylinder 17 is formed with two circumferential grooves 172 extending in the circumferential direction on the inner circumferential surface thereof at predetermined intervals in the optical axis direction, and each circumferential groove 172 has a first rectilinear guide ring. A key 181 projecting from the outer peripheral surface of the key 18 is fitted. Therefore, the first external cylinder 17 includes the key 181 and the circumferential groove 172.
And is relatively rotated with respect to the first rectilinear guide ring 18, but is regulated so as to advance and retreat together in the optical axis direction. Therefore, when the zooming motor 15 rotates, the reduction gear train 15a, the pinion 16, and the gear 14b
, The first helicoid ring 14 rotates, the first helicoid ring 14, the first external cylinder 17 and the first straight guide ring 18
Move forward and backward in the optical axis direction. At this time, the first helicoid ring 14 and the first external cylinder 17 advance and retreat in the optical axis direction while rotating in accordance with the leads of the female helicoid 12a and the male helicoid 14a, and the first straight guide ring 18 does not rotate and the first helicoid ring 18 does not rotate.
It advances and retracts in the optical axis direction together with the helicoid ring 14 and the first external cylinder 17. In addition, the connecting portion 141 and the connecting portion 17
1, the key 181 and the circumferential groove 172 are such that the first helicoid ring 14 and the first external cylinder 17 and the first external cylinder 17 and the first straight guide ring 18 are at a predetermined relative rotation angle (assembly / disassembly position). It is formed so as to be sometimes disengaged by moving in the optical axis direction. The movement position of the first rectilinear guide ring 18 in the optical axis direction with respect to the fixed cylinder 12 is a stepwise zoom step at a predetermined interval, and the brush 19 and the code plate 20 fixed to the first rectilinear guide ring 18 and the fixed cylinder 12 respectively. Is detected by In addition, a decorative ring 174 is provided at the tip of the first external cylinder 17.
Is fixed.

A female helicoid 18b is formed on the inner periphery of the first rectilinear guide ring 18, and the male helicoid 2b formed on the outer periphery of the second helicoid ring 21 is formed on the female helicoid 18b.
1a is screwed. The second helicoid ring 21 is provided with a pair of guide pieces 21b on the outer periphery thereof.
Is a frame escape groove 18c formed in the first linear guide ring 18.
And engages with a frame guide groove 17a (FIGS. 6 and 8) formed on the inner periphery of the first external cylinder 17. Top escape groove 18
c is a through-hole having the same inclination as the female helicoid 18b, and the frame guide groove 17a is a straight groove parallel to the optical axis O of the zoom lens system. The guide piece 21b is formed in a columnar shape with a circular cross section at a portion penetrating the piece escape groove 18c.
The leading end fitting into the frame guide groove 17a is the frame guide groove 1
It is formed in the shape of a rectilinear key having a rectangular cross section that is long in the direction in which 7a extends.

A second external cylinder 23 is connected to the front of the second helicoid ring 21. First helicoid ring 14 and first
Similarly to the external appearance tube 17, the second helicoid ring 21 and the second external appearance tube 23 are formed at the joint (recess) 211 formed at the front end of the second helicoid ring 21 and at the rear end of the second external appearance tube 23. It is connected so that it may rotate and move forward and backward integrally by the engagement of the connecting portion (projection) 231. Coupling part 141,
Similarly to 171, these coupling portions 211 and 231 also
When the helicoid ring 21 and the second external cylinder 23 are at a specific relative rotation angle (assembly / disassembly position), they are formed to be detachable.

Inside the second external cylinder 23, the second external cylinder 23 is provided.
The second linear guide ring 25, which is relatively rotatable and moves together in the optical axis direction (cannot move relative to the optical axis direction), is supported. The second rectilinear guide ring 25 allows only the rectilinear movement in the optical axis direction with respect to the first rectilinear guide ring 18 by engaging the rectilinear guide protrusion 25a with the rectilinear guide groove 18d of the first rectilinear guide ring 18. It is supported by.

The second external cylinder 23 is formed with two circumferential grooves 232 extending in the circumferential direction on the inner circumferential surface thereof at predetermined intervals in the optical axis direction, and each circumferential groove 232 has a second straight guide ring. A key 251 protruding from the outer peripheral surface of 25 is fitted. Therefore, the second external cylinder 23 is provided with the key 251 and the circumferential groove 232.
And is relatively rotated with respect to the second straight guide ring 25, but is regulated so as to advance and retreat together in the optical axis direction.

Accordingly, when the zooming motor 15 rotates, the first helicoid ring 14 and the first external cylinder 17 advance and retreat while rotating via the reduction gear train 15a and the pinion 16, and the first straight guide ring 18 does not rotate. , The combined body of the second helicoid ring 21, the second external cylinder 23, and the second straight guide ring 25 advances and retracts in the optical axis direction. At this time, the second helicoid ring 21 and the second external cylinder 23 are combined with the first external cylinder 17 together with the first external cylinder 17 by the engagement relationship between the guide piece 21b and the frame escape groove 18c and the frame guide groove 17a. While rotating forward and backward in the optical axis direction relative to the first external appearance cylinder 17 according to the leads of the male helicoid 21a and the female helicoid 18b,
The second rectilinear guide ring 25 is restricted by the engagement between the rectilinear guide protrusion 25a and the rectilinear guide groove 18d, and moves forward and backward together with the second helicoid ring 21 and the second external cylinder 23 without rotating. In addition, the coupling unit 211 and the coupling unit 231, and the key 25
1 and the circumferential groove 232, the optical axis when the second helicoid ring 21 and the second external cylinder 23 and the second external cylinder 23 and the second straight guide ring 25 are at a predetermined relative rotation angle (assembly / disassembly position). It is formed so as to be disengageable by moving in the direction.

Similarly to the first linear guide ring 18, a female helicoid 25b is formed on the inner peripheral surface of the second linear guide ring 25.
This female helicoid 25b has a third external cylinder (cam ring) 3
The male helicoid 30a formed on the outer periphery of the rear end of the 0 is screwed. The third external cylinder 30 also serves as a third helicoid ring, and has a pair of guide pieces 30b on the outer periphery of the rear end thereof. Each guide piece 30b passes through a piece escape groove 25c formed in the second straight guide ring 25. 8, and is engaged with a frame guide groove 23a formed in the inner periphery of the second external cylinder 23 (FIG. 8, FIG.
(FIG. 14). The guide piece 30b is formed in a cylindrical shape having a circular cross section at a portion penetrating the piece escape groove 25c.
The portion to be fitted into the frame guide groove 23a is formed in a rectangular cross section that is long in the direction in which the frame guide groove 23a extends. The frame escape groove 25c is a through-hole having the same inclination as the female helicoid 25b, and the frame guide groove 23a is a straight groove parallel to the optical axis O.

The third external cylinder 30 is provided inside the third external cylinder 30.
And a third rectilinear guide ring 33 which can rotate relative to the optical axis and move together in the optical axis direction (cannot move relative to the optical axis). The third rectilinear guide ring 33 has a plurality of rectilinear guide protrusions 33a formed on the outer periphery thereof, and each of the rectilinear guide protrusions 33a is engaged with the rectilinear guide groove 25d on the inner periphery of the second rectilinear guide ring 25, so that the third rectilinear guide ring 33 in the optical axis direction. Only straight travel is possible.

Therefore, when the zooming motor 15 rotates, the first helicoid ring 14 and the first external cylinder 17 advance and retreat in the optical axis direction while rotating, and the first straight guide ring 18 does not rotate but the first helicoid ring 14 does not rotate. And the first external cylinder 17
And the second helicoid ring 21 and the second external cylinder 23 relatively advance and retreat in the optical axis direction while rotating together with the first external cylinder 17 at the same rotational speed. (2) The second helicoid ring 21 without rotating the straight guide ring 25
And the third exterior tube 30 and the third rectilinear guide ring 33 are connected to the second exterior tube 23 by the coupling relationship between the guide piece 30b, the frame escape groove 25c, and the frame guide groove 23a. They rotate together at the same rotational speed and have a male helicoid 30a and a female helicoid 25b.
The third rectilinear guide ring 33 is moved forward and backward relative to the second external appearance tube 23 in the optical axis direction in accordance with the lead of the third linear guide ring 33.
a and the rectilinear guide groove 25d, and moves back and forth in the optical axis direction together with the third external cylinder 30 without rotating. In addition, in the third external appearance tube 30, a portion in front of a portion where the helicoid 30a is provided is exposed from the second external appearance tube 23 to constitute the external appearance of the lens barrel.

In the third appearance tube 30, a fourth appearance tube (lens support tube) 31 having a first variable power lens unit (first sub group S1, second sub group S2) L1 in order from the front.
And the rear group lens frame 32 to which the second variable power lens unit L2 is fixed.
The fourth external cylinder 31 and the rear lens group 32 are guided straight by the third rectilinear guide ring 33 in the optical axis direction. Specifically, as shown in FIGS. 9 and 10, three partial cylindrical arms 33b constituting the third rectilinear guide ring 33 have optical axes O on their front and back surfaces (outer and inner peripheral surfaces). Are formed in parallel with the straight guide grooves 33c, 33d. A straight guide projection (not shown) provided on the inner periphery of the fourth external cylinder 31 is slidably fitted in each straight guide groove 33c. Guide groove 3
A straight guide projection 32a provided on the outer periphery of the rear lens frame 32 is slidably fitted in 3d.

A bottomed cam groove 35 and a bottomed cam groove 36 for the fourth appearance cylinder 31 and the rear lens frame 32 are formed on the inner peripheral surface of the third appearance cylinder 30. FIG. 12 shows a developed shape of the bottomed cam grooves 35 and 36. The bottomed cam groove 35 and the bottomed cam groove 36 are respectively formed in three sets at equal angular intervals in the circumferential direction, and the fourth external cylinder 31 and the rear group lens frame 3 are formed.
2 has follower projections 31a and 32b fitted in the bottomed cam groove 35 and the bottomed cam groove 36 so as to protrude in the radial direction. Therefore, the fourth external cylinder 31 and the rear group lens frame 32 move in the optical axis direction while the zooming motor 15 rotates and the third external cylinder 30 rotates together with the first external cylinder 17 and the second external cylinder 23. Reciprocates relatively, and the third straight guide ring 3
When the third member 3 advances and retreats in the optical axis direction together with the third external cylinder 30 without rotating, the straight guide protrusion (not shown) and the straight guide groove 33 are formed.
c and does not rotate due to the engagement relationship with
Due to the engagement relationship between the a and 32b and the bottomed cam grooves 35 and 36, the third outer cylinder 30 advances and retreats in the optical axis direction with a predetermined locus. In addition, the fourth external appearance tube 31 is configured such that a portion in front of a rear end portion where the follower projection 31 a is formed to project is the third external appearance tube 30.
And is exposed to the outside to constitute the appearance of the lens barrel.

The zoom lens barrel is arranged such that a first straight guide ring 18, a second straight guide ring 25, a third straight guide ring 25,
In this configuration, the straight guide ring 33 and the fourth external cylinder 31 move relatively straight (linear) in the optical axis direction without rotating.

In FIG. 12, each of the bottomed cam groove 35 and the bottomed cam groove 36 is a normal use area from the tele end position (T end) to the storage position (storage). The follower projection 31a and the follower projection 32 are located between the tele end position (T end) and the wide end position (W end).
Guide b. The bottomed cam groove 36 is located at the tele end position (T
End) and wide end position (W end) intermediate discontinuous position 36
a. The first variable power lens unit L1 in the fourth external cylinder 31 guided by the bottomed cam groove 35 moves the first sub-unit S1 and the second sub-unit S2 closer to each other between the telephoto end position and the wide end position. And a switching function of moving the lens to the separation position. When the first variable power lens unit L1 switches,
The second variable power lens unit L2 passes through the intermediate discontinuous position 36a of the bottomed cam groove 36. The section at the intermediate discontinuity position 36a is not used for photographing as an actual zooming area (third section).
The external cylinder 30 is not stopped). The bottomed cam grooves 35 and 36 have a region extending from the tele end position to a disassembly / assembly position. That is, assembly and disassembly of the zoom lens barrel are performed in a state where the zoom lens barrel is rotated to the disassembly and assembly position.

[Shutter Block] A shutter block 40 is provided in the fourth external cylinder 31. A front sub-group frame 45 and a rear sub-group frame 46 are fitted in the shutter block 40. The first sub-group S1 is fixed to the front sub-group frame 45, and the second sub-group S2 is fixed to the rear sub-group frame 46.
Has been fixed. Front sub-group frame 45 (first sub-group S
1) and the rear sub-group frame 46 (the second sub-group S2) are moved by the focusing cam mechanism driven by the forward / reverse drive motor 53 so that the relative position in the optical axis direction between the wide end and the tele end is wide. The position is switched to two positions: the position and the approach position for telephoto. At each position, the light is further advanced and retracted in the optical axis direction by a forward / reverse drive motor 53 via a focusing cam mechanism, and used for focusing. In the shutter block 40, a lens shutter device having a shutter sector 60 and an aperture mechanism having an aperture sector 62 are further provided behind the second sub-group S2. In the present zoom lens barrel, the shutter sector 60 is a blade that has both a variable aperture function for determining an arbitrary aperture value and a shutter function, and an opening amount (aperture) of the shutter sector 60 according to the exposure value at the time of shutter release. Value) and the opening time (shutter speed) are electrically controlled via the control circuit 81. on the other hand,
The aperture sector 62 is provided in order to regulate the maximum value of the photographing aperture diameter particularly at the wide-side photographing distance, and the opening amount mechanically changes according to the extended state of the entire zoom lens barrel. In other words, the size of the aperture is restricted so that the periphery of the zoom lens system is not used for photographing at a wide photographing distance.

The aperture driving ring 63 for opening and closing the aperture sector 62 has a driven projection 63 b on the outer periphery thereof, and the driven projection 63 b is a partial cylindrical arm 33 of the third rectilinear guide ring 33.
b engages with the aperture control cam groove 71 formed on the inner periphery (FIG. 10). During zooming, the third rectilinear guide ring 33 and the shutter block 40 (aperture drive ring 63) relatively move in the optical axis direction. Then, the driven projection 63b is moved in the circumferential direction according to the aperture control cam groove 71, the aperture drive ring 63 is rotated, and the opening degree of the aperture sector 62 is changed. As shown in FIG. 11, the aperture control cam groove 71 has a linear regulating portion 71a parallel to the optical axis O and an inclination regulating portion 71b inclined with respect to the optical axis O.
And a regulation release portion 71c that opens at the front end of the third rectilinear guide ring 33. The width of the linear regulation portion 71a and the inclination regulation portion 71b is such that the driven projection 63b fits almost without play. I have.

The electric components of the shutter block 40 and the control circuit 81 (FIG. 13) in the camera body are connected by a shutter block FPC (flexible printed circuit board) 80. The shutter block FPC 80 changes the folding position in accordance with a change in the relative position between the shutter block 40 and the control circuit 81 due to the extension and storage operations of the zoom lens barrel, and moves the Z so as to avoid interference with other lens barrel constituent members. It is folded back in the shape of a letter and stored between the external appearance tubes (see FIG. 2). In the shutter block FPC 80 of the present embodiment, the folded portions 801 and 802 folded in a hairpin shape have a gap between the first external cylinder 17 and the first straight guide ring 18 from the rear to the front, and a second external cylinder. The folded portion 802 which is inserted from the rear to the front in the gap between the second straight guide ring 25 and the second straight guide ring 25, and comes out of the second straight tube 23 and the second straight guide ring 25, crosses over the third outer tube 30 to the fourth position. It enters the appearance tube 31 and is connected to the shutter block 40.

[Operation of Entire Zoom Lens Barrel] When the pinion 16 is driven to rotate via the zooming motor 15 in the zoom lens barrel having the above-described configuration, the first helicoid ring 1 is rotated.
4 and the first external cylinder 17 move forward and backward while rotating, and the first straight guide ring 18 advances and retracts in the optical axis direction together with the first helicoid ring 14 and the first external cylinder 17 without rotating, and the second helicoid ring 21 And the second external cylinder 23 moves relative to the first external cylinder 17 in the optical axis direction while rotating at the same rotation speed, and the second helicoid ring 21 and the second The third appearance tube 30 advances and retreats in the optical axis direction while rotating at the same rotational speed with respect to the second appearance tube 23, together with the appearance tube 23, and the third appearance tube 30 moves forward and backward.
The rectilinear guide ring 33 moves back and forth in the optical axis direction together with the third appearance tube 30 without rotating, and the fourth appearance tube 31 relatively moves back and forth in the optical axis direction without rotation (the third appearance tube 30 is the fourth appearance tube). Cylinder 31
Finally, the fourth appearance tube 31 guided straight in the optical axis direction in the third appearance tube 30
(The first variable power lens group L1) and the rear lens group frame 32 (the second variable power lens group L2) are provided with a bottomed cam groove 35 and a bottomed cam groove 36.
, And relatively moves in the optical axis direction along a predetermined locus.

For example, the lens barrel stored state (collapsed state) of FIG.
In FIG. 3, the zoom lens barrel is substantially entirely housed in the camera body 11. When the zooming motor 15 is driven in the lens barrel extending direction from the lens barrel housed state, the zoom lens barrel becomes the wide-angle end in FIG. It is advanced to the shooting position. The zoom lens barrel can be extended from the wide-end photographing position to the telephoto-end photographing position in FIG. 4 by further driving the zooming motor 15 in the lens barrel extending direction. When the zooming motor 15 is further driven in the lens barrel extension direction at the telephoto position, the first external lens barrel 17 and the second external lens barrel 17 shown in FIG.
It can be extended to the disassembly / assembly position of the external cylinder 23. FIG. 6 shows a state in which the first and second external cylinders 17 and 23 have been removed at the disassembly / assembly position.

When the zooming motor 15 is driven in the storage direction opposite to the extending direction, the zoom lens barrel can be changed from the disassembly / assembly state, the tele end state, to the wide end state, and further to the storage (collapsed) state. it can. Actual zooming is controlled stepwise so as to divide the wide-angle end to the telephoto end into a plurality of focal length steps, stop the zooming motor 15 at each focal length step, and perform focusing and exposure. At this time, since the area corresponding to the switching between the first sub-group S1 and the second sub-group S2 described above is not used for photographing, the third external cylinder 30 (the zooming motor 15) is stopped without dividing the steps. Do not let.

FIG. 14 is an exploded view showing the relationship among the second external cylinder 23, the second helicoid ring 21, the second linear guide ring 25, and the guide piece 30b in the storage position as viewed from the outside. In this storage position, the retaining key 251 formed in the outer circumferential surface of the second rectilinear guide ring 25 in the circumferential direction is provided in the inner circumferential groove 232 formed in the inner circumferential surface of the second external appearance cylinder 23 in the circumferential direction.
To restrict the second external cylinder 23 and the second helicoid ring 21 so as to be relatively rotatable and move together in the optical axis direction. Two retaining keys 251 are provided at substantially diametrically separated positions on the same circumference, and two at substantially diametrically separated positions on the same circumference at a predetermined distance in the optical axis direction. It consists of four in total. In addition, guidance piece 3
0b is in the idling region 25c1 of the frame escape groove 25c.

The idling region 25c1 of the frame escape groove 25c
Is an idling section for idling the third external cylinder 30. In other words, when the guide piece 30b enters the idling area 25c1, the guide piece 30b moves along the idling area 25c1 even if the third external cylinder 30 rotates with respect to the second linear guide ring 25, so It does not move relative to the optical axis. The idling region 25c1 is provided in a section between the storage position of the zoom lens barrel and the wide end position.

From this storage position, the zooming motor 15 is rotated in the feeding direction, and when the telescopic end position is reached, the second external cylinder 23, the second helicoid ring 21, the second linear guide ring 25 and the guide piece 30b are moved. FIG. 15 shows the relationship developed in the same manner as FIG. At the tele end position, the second external cylinder 23 and the second linear guide ring 25 are formed such that a part of each of the retaining keys 251 comes out of the circumferential groove 232 and has a cut 2.
33, since a part of each retaining key 251 is in the circumferential groove 232, the second external appearance cylinder 23 is
It engages with the linear guide ring 25 so that it does not move (does not come off) in the optical axis direction, that is, it rotates relatively but moves forward and backward together in the optical axis direction.

From this telephoto end state, the zooming motor 15 is further rotated in the extending direction to reach the disassembly / assembly position, the second external cylinder 23, the second helicoid ring 21, and the second
FIG. 16 shows the relationship between the linear guide ring 25 and the guide piece 30b.
14 is developed and shown in the same manner as FIG. In this disassembly / assembly position, each retaining key 251 is
Exiting from 2 and entering a cut 233. Therefore, at this disassembly / assembly position, the second external cylinder 23 can be moved in the optical axis direction with respect to the second linear guide ring 25.
That is, the second external cylinder 23 can be removed (FIG. 17) and attached (FIG. 16).

In this disassembly / assembly position, when the first and second external cylinders 17 and 23 are pulled out, the guide pieces 21b and 30 are pulled out.
Since b is exposed (FIG. 6), the guide pieces 21b and 3b are further exposed.
When he removes Ob (FIG. 7), a helicoid is formed so that the third external cylinder 30, the second helicoid ring 21, and the first helicoid ring 14 can be further rotated and removed in the feeding direction. That is, the disassembly of the zoom lens barrel can be performed at the disassembly / assembly position. This zoom lens barrel is assembled to the camera body, and the rotation of the zooming motor 15 is controlled so that the zoom lens 15 is not extended from the tele end position to the disassembly / assembly position direction in a completed state where photographing is possible. When a special command or the like is input for repair or the like, the zooming motor 15 is configured to rotate beyond the telephoto end position to the disassembly / assembly position.

In this embodiment, like the second external cylinder 23 and the second straight guide ring 25, the first external cylinder 17 and the first
The rectilinear guide 18 also includes a circumferential groove 172, a cut 173 in the inner peripheral groove, and a retaining key 181, and the first external cylinder 17 with respect to the first rectilinear guide 18 in the disassembly / assembly position.
It can be disassembled and assembled.

[Lens Barrier] A lens barrier mechanism for opening and closing the lens barrel opening in front of the first variable power lens unit L1 is further provided at the tip of the fourth external cylinder 31. The lens barrier mechanism includes a decorative plate 90 fixed to a front portion of the fourth appearance tube 31, a barrier driving ring 91 rotatably supported on the front wall portion 31 b of the fourth appearance tube 31 around the optical axis O, A pair of outer barriers 92 and a pair of inner barriers 93 pivotally supported between the barrier drive ring 91 and the decorative plate 90, respectively.
It has. The decorative plate 90 is provided with a projection (not shown) that rotatably supports the outer barrier 92 and the inner barrier 93. The outer barrier 92 and the inner barrier 93 rotate about the projection, and interlock with each other. The opening of the decorative board 90 is opened and closed. Each of the barriers 92 and 93 includes a barrier urging spring 94.
Is always biased in the closing direction.

The barrier driving ring 91 has barrier engaging projections 91a provided at two locations in the diameter direction, and a driven arm 91b extending rearward in the optical axis direction. The barrier engaging projection 91a engages with the outer barrier 92 or the inner barrier 93 to rotate the barrier driving ring 91.
3 On the other hand, the driven arm portion 91b is the fourth external cylinder 3
1 is inserted through the through hole (not shown) formed in the front wall portion 31b of the front inner peripheral surface into the fourth external cylinder 31, and the driven arm portion 91b is provided with a portion of the third rectilinear guide ring 33. Cylindrical arm 3
3b is formed so as to be slidable in contact with the inclined guide surface 33e formed at the tip of 3b.

The barrier driving ring 91 includes a driving ring urging spring 95.
This causes the barriers 92 and 93 to be rotationally urged to open. The driving ring urging spring 95 has a stronger urging force than the barrier urging spring 94, and in a free state where the barrier driving ring 91 can be rotated by the urging force of the driving ring urging spring 95, the driving ring urging spring 95. Of the barrier drive ring 9
1. Barriers 92 and 93 via barrier engagement projections 91a
To move the barriers 92 and 93 into barrier urging springs 94.
In the open position against the biasing force of In the photographing state between the wide end in FIG. 3 and the tele end in FIG.
1b is not in contact with the inclined guide surface 33e, the barrier drive ring 91 is in a free state, and the barriers 92 and 93 are held at the open position.

In the process of moving the zoom lens barrel from the wide end position in FIGS. 3 and 32 to the storage position in FIGS. 2 and 31,
The inclined guide surface (barrier drive surface) 3 of the third rectilinear guide ring 33
3e (FIG. 9) comes into contact with the driven arm portion 91b of the barrier drive ring 91 to start sliding contact, and the barrier drive ring 91 moves against the drive ring urging spring 95 according to the shape of the inclined guide surface 33e. That is, the barriers 92 and 93 are forcibly rotated in a direction allowing the closing direction rotation. Then, the barrier drive ring 91
The barriers 92, 93, which have been released from the regulation by, rotate to the closed position by the urging force of the barrier urging spring 94 and are held in the closed position.

In the process of moving the zoom lens barrel from the wide end position to the retracted position, the second external appearance tube 23 with respect to the third external appearance tube 30 and the first external appearance tube 23 with respect to the second external appearance tube 23.
The external cylinder 17 has an idling section that rotates together but does not relatively move in the optical axis direction. That is, before the zoom lens barrel as a whole reaches the storage position, in this embodiment, before the fourth appearance tube 31 reaches the storage position with respect to the third appearance tube 30,
The second external appearance tube 23 reaches the storage position in the optical axis direction with respect to the first external appearance tube 17 and enters the idling section. The second external appearance tube 23 starts retreating while rotating together with the first external appearance tube 17, and then moves to the third position. The appearance tube 30 reaches the storage position in the optical axis direction with respect to the second appearance tube 23 and enters the idling section, and the third appearance tube 30, the second appearance tube 23, and the first appearance tube 17 retreat to the storage position while rotating together. I do. Therefore, the inclined guide surface 33e of the third rectilinear guide ring 33 is driven by the driven arm portion 91 of the barrier drive ring 91.
At about the same time as or after the sliding contact is started in contact with b, the second appearance tube 23 and the third appearance tube 30 enter the idling section in this order, and the relative rotation of the third rectilinear guide ring 33 with respect to the fourth appearance tube 31. 4th external appearance tube 31 and 3rd external appearance tube 30 which recede by
That is, the barrier drive ring 91 is rotationally driven in the barrier closing direction by the relative movement of the third rectilinear guide ring 33 in the optical axis direction.

In the process in which the zoom lens barrel is extended from the retracted position to the wide end position, the first and second external appearance tubes and the third external appearance tubes 17, 23, and 30 are extended in the optical axis direction while rotating together. However, the second external cylinder 23 and the third
Since the external appearance cylinder 30 is located in the idling section, the external appearance cylinder 30 rotates along with the first external appearance cylinder 17 and is fed out in the wide end direction together,
The fourth appearance tube 31 is extended in the wide end direction relative to the third appearance tube 30 without rotating. In this idling section, the inclined guide surface 33e of the third rectilinear guide ring 33 moves in the direction away from the driven arm portion 91b, so that the barrier drive ring 91 rotates in the barrier opening direction by the urging force of the drive ring urging spring 95. The barriers 92 and 93 are rotated to the open position by the urging force of the driving ring urging spring 95. And
Before reaching the wide end, the inclined guide surface 33e separates from the driven arm portion 91b, and the barriers 92 and 93 are completely moved to the open position.

In the process of extending the zoom lens barrel from the retracted position to the wide end position, first, the idling section of the third external cylinder 30 ends, so that the third external cylinder 30 is relative to the second external cylinder 23. The feeding starts, and then the idling section of the second external cylinder 23 ends.
Of the first appearance cylinder 17 is also started.

As described above, the opening and closing of the barriers 92 and 93 are as follows.
Since the stroke is performed depending on the relative optical axis direction movement of the fourth appearance tube 31 and the third appearance tube 30 between the storage position and the wide end position, the stroke is performed on one or both of the third appearance tube 30 and the second appearance tube 23. There is also a configuration in which no idle section is provided. However, if the stroke for opening and closing the barriers 92 and 93 is configured to be short, the drive torque increases, so that the stroke is preferably long. However, if the stroke is configured to be long, the rotation angle of the third external cylinder 30 required for opening and closing the barrier is required. Becomes large, and the amount of projection of the fourth external cylinder 31 with respect to the camera body becomes too large, and exceeds the lens extension amount required from the storage position to the wide end position. The idling section can be provided only in the helicoid extension structure of the third external cylinder 30, but in this case, the stroke with respect to the lens barrel rotation angle required for extending the lens from the storage position to the wide end position is reduced, so that the idling section is It is necessary to increase the rotation angle. In other words, since the relative movement distance of the fourth appearance tube 31 in the optical axis direction with respect to the third appearance tube 30 becomes longer, if the play of the portion of the shutter block FPC 80 that straddles the third appearance tube 30 is not increased, this portion may be stretched. (Figures 2 and 3). Therefore, in the embodiment of the present invention, a helicoid idling section is provided in the second external cylinder 23 and the third external cylinder 30 to increase the rotation angle from the storage position to the wide end position, and the cam for extending the fourth external cylinder 31 is provided. Even if the lead is small, the relative movement distance of the fourth appearance tube 31 in the optical axis direction with respect to the third appearance tube 30 can be increased.

The configuration of the idle section of the helicoid will be described with reference to FIGS. FIG. 18A is a perspective view showing the second rectilinear guide ring 25 in a longitudinal section, and FIG.
Is a perspective view showing the first rectilinear guide ring 18 in a longitudinal section, FIG. 19 is an exploded view of the second rectilinear guide ring 25, and FIGS.
Straight running guide ring 25 and third external cylinder (cam / helicoid ring) 3
0 is a developed view showing the relationship of 0, FIG. 23 is a developed view of the first rectilinear guide ring 18, and FIGS.
FIG. 4 is a development view showing a relationship between an appearance cylinder 23 and a second helicoid ring 21. FIGS. 27A, 27B and 27C show the female helicoid 25b of the second straight guide ring 25, the helicoid idle section 25b1, and the male helicoid 3 of the third external cylinder 30.
0a is shown enlarged.

The female helicoid 25b on the inner peripheral surface of the second rectilinear guide ring 25 is a helicoid idling section 25b1 that is wide (wide in the circumferential direction) near the rear end (camera body side) of the second rectilinear guide ring 25. (See FIG. 19). The length of the helicoid idling section 25b1 in the optical axis direction and the third external cylinder 30
Of the optical axis of the male helicoid 30a. That is, when the male helicoid 30a enters the helicoid idle section 25b1, the male and female helicoids 30a, 2b
The restriction by the flank surface of 5b is released, and the movement of the second rectilinear guide ring 25 and the third external cylinder 30 in the optical axis direction is regulated, so that the second linear guide ring 25 and the third external cylinder 30 are relatively rotatable. Top escape groove 25c
Also, an idling section 25c1 for allowing rotation in the helicoid idling section 251b is formed.

When the zoom lens barrel is in the retracted position, the male helicoid 30a helicoidally coupled to the female helicoid 25b is guided into the helicoid idle section 25b1, and the guide piece 30b fitted into the frame escape groove 25c is the idle section. 25c1 (FIG. 20). When the zoom lens barrel is extended from the storage position toward the wide end, the third external appearance cylinder 3 is moved to the second straight guide ring 25.
0, the male helicoid 30a and the guide piece 30b relatively move in the wide direction (right direction in the figure). Since the male helicoid 30a is restricted by the helicoid idling section 25b1, the third external cylinder 30 rotates only relative to the second straight guide ring 25, and reaches the idling section boundary position (FIG. 21).
At the idle section boundary position, the flank of the male helicoid 30a is in contact with the flank of the female helicoid 25b.

When the zoom lens barrel is further extended from the idling boundary position toward the wide position, the second straight guide ring 2
In contrast to 5, since the male helicoid 30a is restrained by the female helicoid 25b, the third external cylinder 30 relatively advances (moves upward in the figure) while rotating according to the lead of the female helicoid 25b, and moves to the wide end position. (Fig. 2
2).

In this embodiment, the third external cylinder 30 is a male helicoid 30a, and the second straight guide ring 25 is a female helicoid 25a.
However, the relationship between the male and female helicoids may be reversed.

The second straight guide ring 25 and the third external cylinder 30
Similarly, the first straight guide ring 18, the second external cylinder 23, and the second helicoid ring 21 also have idle rotation sections. The female helicoid 18b on the inner peripheral surface of the first rectilinear guide ring 18 is a helicoid idle section 18b1 in which the vicinity of the rear end portion (camera body side) of the first rectilinear guide ring 18 is wide (wide in the circumferential direction). (FIG. 23). The length of the helicoid idle section 18b1 in the optical axis direction and the male helicoid 21a of the second helicoid ring 21
Is substantially matched with the length in the optical axis direction. That is, when the male helicoid 21a enters the idle female helicoid region 18b1, the restraint of the male and female helicoids 21a, 18b by the flank surface is released, and the first straight guide ring 18 and the helicoid ring 21 (and the second external cylinder 23). Means a coupled state in which the movement in the optical axis direction is restricted and relatively rotatable. The helicoid idle section 18b is also provided in the top escape groove 18c.
The idle rotation section 18c1 for allowing the rotation at 1 is formed.

When the zoom lens barrel is in the retracted position, the male helicoid 21a helicoidally coupled to the female helicoid 18b is guided into the helicoid idling section 18b1, and the guide piece 21b fitted into the frame escape groove 18c is the idling section. 18c1 (see FIGS. 24 and 27).
(A)). When the zoom lens barrel is extended in the wide end direction from this storage position, the male helicoid 21a and the guide piece 21b with respect to the first rectilinear guide ring 18, that is, the helicoid ring 21 and the second appearance cylinder 23 are in the wide direction (FIG. At the right). During this relative movement, the male helicoid 21a is moved into the helicoid idle section 18
Since the guide piece 21b has entered the idling section 18c1 within b1, the second external cylinder 23 and the second helicoid ring 2
1 rotates only relative to the first straight guide ring 18 and reaches the idling section boundary position (FIGS. 25 and 27B). At the idle section boundary position, the flank surface of the male helicoid 21a is in contact with the flank surface of the female helicoid 18b.

When the zoom lens barrel is further extended from the idling boundary position toward the wide position, the first straight guide ring 1 is moved.
8, a second external cylinder 23 and a second helicoid ring 21
Since the male helicoid 21a is restrained by the female helicoid 18b, the male helicoid 21a advances forward (moves upward in the figure) while rotating according to the leads of the male and female helicoids 21a, 18b and the frame escape groove 18c, and reaches the wide end position (FIG. 26, FIG. 27 (C)).

In this embodiment, it is not sufficient to simply open and close the second appearance tube 23 to open and close the barrier. Therefore, the third appearance tube 30 is also provided with an idling section. The amount of idling of the third external cylinder 30 is set for the purpose of suppressing the amount of feeding and adjusting the balance of feeding. Furthermore, in this embodiment, the rotation angle of the second appearance cylinder 23 is smaller than the rotation angle of the helicoid idling section 25b1 in which the third appearance cylinder 30 idles.
In addition, the rotation angle of the helicoid idling section 18b1 for idling the helicoid ring 21 is set to be larger. When the third appearance tube 30 and the second appearance tube 23 are simultaneously switched from the idling section to the helicoid section, the load suddenly increases, so that the sudden increase in the load can be reduced.

As described above, in this embodiment, the lens barrier is opened and closed by the idling motion of the third external cylinder 30 and the second external cylinder 23 and the relative movement of the fourth external cylinder 31 in the optical axis direction. Thus, in this zoom lens barrel,
The stroke in which the fourth appearance tube 31 moves between the storage position and the wide end position, and the third appearance tube 30 and the second appearance tube 23
Drives the barrier drive ring 91 between the barrier closed position and the barrier open position by the two actions of the rotation angle of the idle rotation in the idle section between the storage position and the wide end position, so that the stroke of the fourth external cylinder 31 is short. Can be supplemented.

FIG. 28A is an enlarged view of the vicinity of the helicoid idle section 18b1 of the female helicoid 18b of the first straight guide ring 18. The first straight guide ring 18 is usually formed by injection molding of a synthetic resin. You. When a mold for this purpose is machined with electrodes for electric discharge machining, when machining the electrodes, for example, the corners of the helicoid idling section 18b1 are rounded, so-called cutters R (FIG. 28).
(B)). When such a cutter R is attached to the corner of the helicoid idling section 18b1, the helicoid idling section 18b1
The circumferential lengths of the thrust surfaces 18b2, 18b2 are short, and the contact area with the male helicoid 21a is also small. It will be stable. Therefore, in this embodiment,
A circumferential groove 18e is formed along each of the front and rear thrust surfaces 18b2 separated from each other in the optical axis direction of the helicoid idling section 18b1.
Was formed, and the cutter R was eliminated by the circumferential groove 18e (FIG. 28C). The width of the circumferential groove 18e (width in the optical axis direction) is set to a width that allows the cutter R to be deleted, that is, approximately equal to the radius of the cutter R.

In this embodiment, a circumferential groove 25e similar to the circumferential groove 18e of the first linear guide ring 18 is formed along the front and rear thrust receiving surfaces of the helicoid idling section 25b1 of the second straight guide ring 25. It is formed.

When the male helicoid 21a enters the female helicoid 18 from the helicoid idling section 18b1, if the second helicoid ring 21 and the first rectilinear guide ring 18 are misaligned or tilted, the male helicoid 21a May come into contact with the thrust surface 18b2 and not enter the female helicoid 18. Therefore, in the embodiment of the present invention, fitting portions (convex portions) 18f and 25f are formed on the inner peripheral surfaces near the rear ends of the first linear guide ring 18 and the second linear guide ring 25 so as to protrude in the circumferential direction. (FIGS. 18A and 18B).
The second helicoid ring 21 and the third external cylinder 30 that have been retracted to the storage position are fitted into these fitting portions 18f and 25f without any gap in a state where the second helicoid ring 21 and the third external cylinder 30 can be slidably contacted (FIG. 29). The second helicoid ring 21 and the third external cylinder 30 are each fitted with the fitting portion 18.
The idle rotation section is rotated while sliding on f and 25f.

Since the positions of the male helicoids 21a, 30a in the diametrical direction are regulated by the fitting portions 18f, 25f, the male helicoids 21a, 30a are moved from the helicoid idling sections 18b1, 25b1 to the female helicoids 18b, 2b.
5b can be smoothly and reliably entered. Then, by the helicoid action, the second helicoid ring 21 and the third external cylinder 3
0 can be moved forward and backward while rotating from the wide end position (FIG. 30) to the tele end position.

In this embodiment, the first straight guide ring 1
8 and a fitting portion 18f on the outer peripheral surface of the second linear guide ring 25,
25f, but the helicoid idling regions 18b1, 2b
A configuration in which the bottom of 5b1 is gradually raised to eliminate play may be used.

[0060]

As apparent from the above description, the present invention provides
In a zoom lens barrel having a multi-stage extension barrel with a helicoid extension structure, a helicoid idling region that does not extend even when the barrel rotates between a storage position of the zoom lens barrel and a shortest extension position at which photographing is possible is provided. The helicoid idling region includes a female helicoid formed in one barrel and a male helicoid formed in the other barrel, and the male helicoid is formed when the one barrel and the other barrel are in the storage position. The helicoid idle region that allows circumferential rotation of the helicoid is formed in the female helicoid, and the circumferential groove is formed along the thrust surface of the helicoid idle region. Can be formed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of constituent members showing a zoom lens barrel according to an embodiment of the present invention.

FIG. 2 is an upper half sectional view of the zoom lens barrel in a housed state.

FIG. 3 is an upper half sectional view of the zoom lens barrel in a wide-end shooting state.

FIG. 4 is an upper half sectional view of the zoom lens barrel in a telephoto end photographing state.

FIG. 5 is a perspective view showing a state in which the zoom lens barrel is extended.

6 is a perspective view of the zoom lens barrel with a part of the lens barrel exterior member removed from FIG. 5;

7 is a perspective view of the zoom lens barrel further disassembled than FIG.

FIG. 8 is a single perspective view of a first external cylinder and a second external cylinder.

FIG. 9 is a single perspective view of a third rectilinear guide ring.

FIG. 10 is an exploded perspective view illustrating a relationship between a third rectilinear guide ring and a shutter block.

FIG. 11 is a development view of the third rectilinear guide ring, showing a throttle control cam groove of the third rectilinear guide ring.

FIG. 12 is a development view of an inner surface of the cam ring, showing an example of a cam groove shape of the cam ring.

FIG. 13 is a block diagram showing a control system of the zoom lens barrel whose entire structure is shown in FIGS. 2 to 4;

FIG. 14 is a view showing a second position of the zoom lens barrel in a storage position;
It is a development view which shows the relationship of an external appearance cylinder, a 2nd helicoid ring, a 2nd linear guide ring, and a guide piece.

FIG. 15 is a development view showing a relationship among a second external cylinder, a second helicoid ring, a second linear guide ring, and a guide piece at a tele end position of the zoom lens barrel.

FIG. 16 is a development view showing a relationship among a second external cylinder, a second helicoid ring, a second linear guide ring, and a guide piece at a disassembled / assembled position of the zoom lens barrel.

FIG. 17 is an exploded view showing the relationship between the second external cylinder, the second helicoid ring, the second linear guide ring, and the guide piece in a disassembled / assembled position of the zoom lens barrel with the second external cylinder removed. .

FIG. 18A is a perspective view showing a second straight guide ring 25 of the zoom lens barrel in a longitudinal section, and FIG. 18B is a perspective view showing a third straight guide ring 18 of the zoom lens barrel in a longitudinal section. It is a perspective view.

FIG. 19 is a development view showing a second straight guide ring of the zoom lens barrel.

FIG. 20 shows a second state in which the zoom lens barrel is housed.
FIG. 10 is a development view showing a relationship between a female helicoid of the straight guide ring 25 and a male helicoid of the third external cylinder 30.

FIG. 21 is a developed view showing a relationship between a female helicoid of the second straight guide ring 25 and a male helicoid of the third external cylinder 30 when the zoom lens barrel is extended to the idling section boundary position.

FIG. 22 is a developed view showing the relationship between the female helicoid of the second rectilinear guide ring and the male helicoid of the third appearance tube when the zoom lens barrel is extended to the wide end position.

FIG. 23 is a development view showing a first straight guide ring of the zoom lens barrel.

FIG. 24 is a developed view showing a relationship between the first straight guide ring, the second external cylinder 23, and the second helicoid ring when the zoom lens barrel is in a housed state.

FIG. 25 is a developed view showing the relationship between the first straight guide ring, the second external appearance cylinder 23, and the second helicoid ring when the zoom lens barrel is at the boundary position of the idling section.

FIG. 26 is a developed view showing a relationship between the first straight guide ring, the second external appearance cylinder 23, and the second helicoid ring when the zoom lens barrel is extended to the wide end position.

FIG. 27 is an expanded view showing a relationship between a female helicoid, a helicoid idle section, and a male helicoid of a second helicoid ring of the first straight guide ring of the zoom lens barrel, and FIG.
FIG. 5B is a diagram illustrating a state of storage, FIG. 6B illustrates a state at a boundary position of an idling section, and FIG.

28A is a diagram schematically showing the shape of a female helicoid and a helicoid idling section of the first straight guide ring, FIG. 28B is a diagram for explaining a problem that occurs at the time of mold production, and FIG. FIG. 3 is a diagram showing an embodiment of the present invention for solving this problem.

FIG. 29 is an upper half section of the stored state of the embodiment in which a convex portion extending in the circumferential direction is formed on the inner peripheral surface near the rear end of the first straight guide ring and the second straight guide ring of the zoom lens barrel; FIG.

FIG. 30 shows a state where a convex portion extending in the circumferential direction is formed on the inner peripheral surface near the rear end of the first straight guide ring and the second straight guide ring of the zoom lens barrel, in the wide-end shooting state. It is a half sectional view.

FIG. 31 is an enlarged top sectional view of the vicinity of a shutter block in a state where a lens barrier is closed in the zoom lens barrel.

FIG. 32 is a top sectional view similar to FIG. 31, showing a state where a lens barrier is opened in the zoom lens barrel.

[Explanation of symbols]

L1 First variable power lens group L2 Second variable power lens group O Optical axis S1 First sub group S2 Second sub group 11 Camera body 12 Fixed cylinder 12a Female helicoid 12b Straight guide groove 14 First helicoid ring 14a Male helicoid 14b Gear 141 Joining part 15 Zooming motor 16 Pinion 17 First appearance cylinder 17a Coma guide groove 171 Joining part 172 Inner circumferential groove 173 Break in inner circumferential groove 18 First straight guide ring 18a Straight guide protrusion 18b Female helicoid 18b1 Helicoid idle section 18b2 thrust Surface 18c Frame escape groove 18d Straight guide groove 18e Circumferential groove 181 Retaining key 19 Brush 20 Code plate 20 21 Second helicoid ring 21a Male helicoid 21b Guide piece 211 Coupling part 23 Second external appearance cylinder 23a Coma guide groove 231 Coupling part 232 Inner circumferential groove 23 Notch of inner circumferential groove 25 Second straight guide ring 25a Straight guide projection 25b Female helicoid 25b1 Helicoid idle section 25c Coma escape groove 25d Straight guide groove 25e Circumferential groove 25f Fitting portion 30 Third external cylinder (cam ring) 30a Male helicoid 30b Guide piece 31 Fourth appearance tube (lens support tube) 31a Follower protrusion 31b Front wall 32 Rear group lens frame 32a Straight guide protrusion 32b Follower protrusion 33 Third straight guide ring 33a Straight guide protrusion 33b Partial cylindrical arm 33c 33d Straight guide groove 33e Inclined guide surface 35 36 Bottomed cam groove 36a Intermediate discontinuous position 40 Shutter block 80 FPC (flexible printed circuit board) for shutter block 80A Annular FPC 80B Strip FPC 81 Control circuit 81A Focal length information 81B Subject distance information 81C Utsushitai luminance information 91 barrier drive ring 91a barrier engaging projection 91b Hidoude 92 outer barrier 93 inner barrier 94 barrier biasing spring 95 the drive ring biasing spring

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazunori Ishizuka 2-36-9 Maenocho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. (72) Maiko Takashima 2-36, Maenocho, Itabashi-ku, Tokyo No. 9 Asahi Gaku Kogyo Co., Ltd. F term (reference) 2H044 BD03 BD06 EF01 EF08 2H083 CC24 CC28 CC47 2H101 BB05 BB08

Claims (3)

[Claims] 1. A zoom lens barrel having a multi-stage extending barrel, wherein each of a lens barrel from a lens barrel connected to a fixed part of a camera body to a lens barrel to which a most advanced lens barrel is connected. At least one of the sets is connected by a helicoid extension structure, the most advanced lens barrel and the rear-stage lens barrel are connected by a cam extension structure, and the helicoid extension structure that connects the latter-stage lens barrel and another lens barrel includes: A helicoid idling area that does not extend even when rotated from the storage position of the zoom lens barrel to the shortest extendable position at which photographing is possible is provided. And a male helicoid formed in the other lens barrel, wherein the helicoid allows the male helicoid to rotate in the circumferential direction when the one lens barrel and the other lens barrel are in the storage position. The de idling region formed in the female helicoid, feeding structure of a zoom lens barrel, characterized in that along each thrust surface against the said helicoid idling region to form circumferential grooves. 2. The helicoid pay-out structure having a helicoid idling region and a circumferential groove is a helicoid ring formed by injection molding of a synthetic resin using a mold.
The extension structure of the described zoom lens barrel. 3. A helicoid feeding structure having a pair of lens barrels connected by a helicoid feeding structure, the helicoid feeding structure including a helicoid idling region that does not extend even when rotated. A female helicoid formed in one lens barrel and a male helicoid formed in the other lens barrel, and when the one lens barrel and the other lens barrel are at specific positions, rotate the male helicoid in the circumferential direction. A feed-out structure for a zoom lens barrel, wherein an allowable helicoid idling region is formed in the female helicoid, and circumferential grooves are formed along opposing thrust surfaces in the helicoid idling region of the female helicoid.