JP2003005016A - Zoom lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a zoom lens barrel which can suppress abnormal sound, vibration, wiring peeling, etc. SOLUTION: A flexible printed wire 15 has at least one folded part 15a when extending from a helicoid member 1 toward a unit along the optical axis and a fitting plate 14 has a 1st beam part 14c sandwiched in the folded part 15a and a 2nd beam part 14d which is provided closer to a camera body side than to the 1st beam part 14c and supports the flexible printed wire 15 closely to the optical side, so even if the flexible printed wire 15 bends when a cam cylinder 4 moves toward a helicoid member 1, the 2nd beam part 14d can suppress the inward spreading of the bent flexible printed wire 15 at right angles to the optical axis, so interference between the bent flexible printed wire 15 and cam cylinder 4 which is possibly caused in the absence of the 2nd beam part 14d can effectively be suppressed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a plurality of payouts.
The present invention relates to a zoom lens barrel which is equipped with a freely retractable barrel and is suitable for a compact camera.

[0002]

2. Description of the Related Art Compact cameras are used by a wide range of users because they have a compact body and thus are excellent in storability and portability. Here, even with a compact camera, there is a demand to shoot various scenes by making the shooting angle of view variable,
For this reason, compact cameras equipped with zoom lenses are now the mainstream.

Here, in the zoom lens, since a plurality of lens groups must be moved in the optical axis direction,
In order to secure a large so-called zooming ratio and to ensure compactness during storage, a telescopic lens barrel that can be freely extended is often provided. In general, if the maximum lengths are the same, the two-stage zoom lens barrel
The three-stage extension zoom lens barrel has an advantage that the length in the optical axis direction during storage can be shortened.

[0004]

On the other hand, in some types of compact cameras, a lens shutter is provided. The lens shutter has a shutter arranged near the lens. Here, the lens shutter is for opening and closing a plurality of blades by a driving unit at a predetermined shutter speed, and the CPU on the camera body side controls the opening and closing. Between the CPU and the drive,
Control signals are connected to be transmitted by a relatively inexpensive flexible printed wiring board.

Here, since the zooming lens is provided in the cylinder closest to the subject, if the printed wiring board is extended from the CPU of the camera body to the drive unit near the lens, it is considerably large. Long ones are needed. However, when the lens barrel is collapsed, CP
Since the U and the driving unit are close to each other, the printed wiring board is slackened, and its handling becomes a problem. In particular, in the three-stage extension zoom lens barrel, the degree of approach between the CPU and the drive unit is further increased, and the elastic force of the flexible printed wiring board tends to further increase the radius of slack, so that the lens barrel sags in a thin barrel. There is a possibility that the lower part may come into contact with the member and cause abnormal noise or vibration, or may cause the wiring board to peel off due to long-term use.

On the other hand, there is an idea to solve the above-mentioned problem by using a so-called U-shaped wiring board which is formed by bending it with a small radius in advance. However, since the U-shaped wiring board is relatively expensive, the use of the wiring board increases the manufacturing cost of the compact camera.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a zoom lens barrel capable of suppressing the occurrence of abnormal noise, vibration, peeling of wiring, and the like.

[0008]

A zoom lens barrel according to the present invention comprises a fixing member attached to a camera body, a first barrel movable in the optical axis direction with respect to the fixing member, and a predetermined driving unit. A second tube movable in the optical axis direction with respect to the first tube, a flexible wiring extending at least from the drive unit to the fixing member, and the flexible wiring to the first tube. Attaching means for attaching, the flexible wiring has at least one turn-back portion when extending toward the drive portion in the optical axis direction from the fixing member, and the attaching means has the turn-back portion. And a second beam portion that is provided closer to the camera body than the first beam portion and that supports the flexible wiring on the side closer to the optical axis.

[0009]

According to the zoom lens barrel of the present invention, the zoom lens barrel includes a fixing member attached to the camera body, a first barrel movable in the optical axis direction with respect to the fixing member, and a predetermined drive section. A second tube movable in the optical axis direction with respect to the first tube; a flexible wiring extending at least from the drive unit to the fixing member; and an attachment means for attaching the flexible wiring to the first tube. The flexible wiring has at least one folding portion when extending from the fixing member in the optical axis direction toward the driving portion, and the mounting means is sandwiched between the folding portions. Since the first beam portion and the second beam portion provided on the camera body side of the first beam portion and supporting the flexible wiring on the side closer to the optical axis are provided, the second tube is fixed to the fixed portion. Move to the member Even when the flexible wiring is bent, the folded portion can be supported by the first beam portion, and the second beam portion can prevent the bent flexible wiring from spreading in the direction approaching the optical axis. Therefore, if the second beam portion does not exist, it is possible to effectively suppress the interference between the bent flexible wiring and other members, which is likely to occur.

Further, if a cam barrel movable in the optical axis direction is provided with respect to the first barrel, and the second barrel is movable in the optical axis direction with respect to the cam barrel. The zoom lens barrel can be of a three-stage extension type, and in that case, since the amount of bending of the flexible wiring also increases, the risk of occurrence increases if the second beam portion does not exist. The interference between the flexible wiring and other members can be effectively suppressed.

Further, if the attaching means is a plate member provided with the first beam portion and the second beam portion, the cost can be kept low and the assembling can be facilitated.

Further, when the plate member is arranged in the opening formed in the peripheral surface of the first cylinder and is fixed by the tape, the assembling property can be enhanced.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to the embodiments. FIG. 1 is a cross-sectional view of a zoom lens barrel according to the present embodiment, in which the lower half shows a state at the telephoto end and the upper half shows a state at the wide-angle end. Figure 2
FIG. 4 is a sectional view of the lens barrel according to the present embodiment when it is retracted (completely retracted).

In FIGS. 1 and 2, a cylindrical helicoid member (fixing member) 1 fixed in a camera body (not shown) has a female helicoid 1a formed on its inner peripheral surface. A rotating cylinder 2 having a male helicoid 2a that engages with the female helicoid 1a formed on the outer peripheral surface is attached so as to be included in the helicoid member 1.

A straight advance cylinder (first cylinder) contained in the rotary cylinder 2.
3 is arranged so as to move integrally with the rotary cylinder 2 in the optical axis direction. The film surface side of the rectilinear barrel 3 in the optical axis direction (see FIG. 1).
A protrusion (not shown) is formed on the outer periphery of the end portion on the right side), and the protrusion engages with a guide groove (not shown) formed on the inner periphery of the helicoid member 1 and extending in the optical axis direction. Therefore, the rectilinear barrel 3 is rotatably supported by the helicoid member 1 regardless of the rotation of the rotary barrel 2 and is movable only along the optical axis direction.

A female helicoid 3a is formed on the inner periphery of the straight-moving barrel 3, and a cam barrel 4 in which a male helicoid 4a that engages with the female helicoid 3a is formed on the outer periphery of the film surface side end,
It is contained in the rectilinear barrel 3 and is arranged so as to be movable in the optical axis direction with respect to it.

As shown in FIG. 2, the drive pin 5 provided on the outer periphery of the cam barrel 4 has a groove 2 formed on the inner periphery of the rotary barrel 2.
The cam cylinder 4 and the rotary cylinder 2 are engaged with each other so that they rotate in the same phase.

On the inner circumference of the end portion of the cam cylinder 4 on the film surface side, three projections 4d formed at intervals in the circumferential direction limit the position in the optical axis direction by ribs 6b formed on the outer circumference of the straight guide ring 6. Has been done. The linear guide ring 6 moves integrally with the cam barrel 4 in the optical axis direction, and is relatively rotatable. Since the protrusion 6a formed on the outer periphery of the film surface side end of the rectilinear guide ring 6 is fitted in the rectilinear groove 3b of the rectilinear cylinder 3, the rectilinear guide ring 6 should rotate relative to the rectilinear cylinder 3. Instead, it moves in the optical axis direction. still,
The straight guide ring 6 has a second lens group 10 for holding the second lens group 10.
A notch (not shown) is provided to avoid interference with the lens frame 11.

Returning to FIG. 1, a female helicoid 4b and a cam groove 4c are formed on the inner peripheral surface of the cam barrel 4. Cam barrel 4
A front cylinder (second cylinder) 7 having a male helicoid 7a that engages with the female helicoid 4b is formed on the outer peripheral surface so as to be included in the cam cylinder 4. The front cylinder 7 is configured such that a key portion (not shown) of the straight-movement guide ring 6 is fitted therein so that the straight movement is possible.

A shutter unit 8 for driving the shutter blades 8a to open and close, and a first lens frame 12 for holding a first lens group 9 are attached to the front barrel 7. Further, a key portion (not shown) of the second lens frame 11 is fitted in a straight advance groove (not shown) of the front barrel 7, and a cam pin 11a is fitted in a cam groove 4c inside the cam barrel 4.

A thin and elongated plate-shaped flexible printed wiring 15 is folded back from the shutter unit 8 which is a drive unit along the inner circumference of the front cylinder 7 and the inner circumference of the cam cylinder 4 at the straight advancing cylinder 3, and from there. The helicoid member 1 extends to reach the inner circumference of the helicoid member 1, passes through the opening 1b of the helicoid member 1 and is pulled out to the outer peripheral surface side, and its end is connected to a CPU of a camera body (not shown).

The operation of this embodiment will be described. When the drive shaft 13 is rotated in either direction by the power from a motor (not shown), the pinion 13a formed on the outer periphery of the drive shaft 13 is rotated.
When the rotary cylinder 2 rotates, the helicoid 1 rotates when the rotary cylinder 2 rotates by receiving a rotational force through the gear portion 2c that meshes with these.
By the action of a and 2a, the rotary cylinder 2 is extended with respect to the helicoid member 1 (moves leftward in FIG. 1).

When the rotary cylinder 2 is extended, the linear cylinder 3 is integrally extended without rotating, and at this time, the cam cylinder 4 is extended while rotating by the action of the helicoids 3a and 4a. When the cam barrel 4 rotates, the helicoid 4
The front cylinder 7 is extended by the action of b and 7a. Front cylinder 7
The first lens group also moves with the movement of. On the other hand, the cam barrel 4
Rotation of the cam pin 11a of the second lens frame 11 causes
Since it moves along the cam groove 4c, the second lens frame 11 is moved relative to the cam barrel 4 in the optical axis direction accordingly, so that the optical axes of the first lens group 9 and the second lens group 10 are changed. The amount of directional movement is different, so at any zoom position,
The subject image can be properly focused on the film surface. By rotating the drive shaft 13 in the reverse direction, the above operation is executed in reverse, and the zoom lens barrel is retracted.

When the photographer presses a release button (not shown) at any zoom position, the CPU inside the camera body
Calculates an appropriate exposure amount, and outputs a signal corresponding thereto via the flexible printed wiring 15 to the shutter unit 8
To the shutter unit 8, the shutter unit 8 drives the shutter blade 8a at an appropriate shutter speed.

FIG. 3 is a perspective view showing a part of the straight advancing cylinder 3 by cutting. In FIG. 3, the back side is the helicoid member 1 (FIG. 1) side, and the front side is the cam barrel 4 side. FIG. 4 is a view of the straight advancement cylinder 3 as seen in the direction of arrow VI in FIG. Here, a rectangular opening 3c is provided on the circumferential surface of the rectilinear cylinder 3. In the rectangular opening 3c, the folded-back portion 15a of the flexible printed wiring 15 is provided with a mounting plate 14 as a mounting means.
Is held by.

As shown in FIG. 4, the mounting plate 14 which is considerably thinner than the wall thickness of the rectilinear barrel 3 has two side portions 14a and 14b extending in the optical axis direction and a first beam connecting them. Part 14
It is composed of c and the second beam portion 14d. As is clear from FIG. 3, the first beam portion 14c is provided on the flexible printed circuit board 15
It is positioned so as to be sandwiched between the folded-back portions 15a, and further, the flexible printed board 15 which is folded back and doubled passes through the outside (the side far from the optical axis) of the second beam portion 14d, and It goes out to the inner peripheral surface, one side is the helicoid member 1
The other side makes a U-turn and faces the cam cylinder 4 side. The outer peripheral surfaces of the mounting plate 14 and the flexible printed wiring 15 are fixed to the outer peripheral surface of the rectilinear cylinder 3 with an adhesive tape 16. Further, the flexible printed circuit board 15 has a sufficient length so as not to hinder the extension of the zoom lens barrel.

5 and 6 are cross-sectional views of the zoom lens barrel according to the present embodiment in a collapsed state, for explaining the effect of the mounting plate 14. First, FIG.
In the comparative example shown in FIG. 3, the double portion extending from the folded-back portion 15 a of the flexible printed circuit board 15 has the mounting plate 14
It passes through the inside and the outside (both sides in the direction intersecting the optical axis). Therefore, when the zoom lens barrel is collapsed, the inner portion of the flexible printed circuit board 15 in the optical axis intersecting direction sags, and the inner portion swells with a large radius due to its own elastic force, and interferes with the outer peripheral surface of the cam barrel 4. There is a risk of

On the other hand, in the present embodiment, as shown in FIG. 6, the folded portion 15a of the flexible printed board 15 sandwiches the first beam portion 14c of the mounting plate 14 and extends from the folded portion 15a. Since both of the parts pass through the outside of the second beam part 14d in the direction intersecting the optical axis, it is possible to suppress the force of expanding the inside of the flexible printed circuit board 15,
Also, when viewed in the state of FIG.
By being bent into an S-shape, it is possible to suppress the floating from the inner peripheral surface of the rectilinear cylinder 3 even after passing through the second beam portion 14d, and thus suppress the interference with the outer peripheral surface of the cam cylinder 4. You can

When the flexible printed circuit board 15 is assembled, a fold line is formed in an appropriate portion of the flexible printed circuit board 15 extending from the front cylinder 7 in a state where the respective cylinders are assembled, and this is used as a folding back portion 15a of the rectilinear tube 3. The first beam portion 14c and the second beam portion 1 of the mounting plate 14 are arranged so that the end portions are once exposed to the outside from the opening 3c and the state shown in FIG.
4d is dipped, and then returned to the inside of the opening 3c. In this state, when the cam cylinder 4 is retracted, the flexible printed board 15 and the mounting plate 14 are pushed outward from the opening 3c, so that the opening 3c is closed and fixed with the adhesive tape 16.

When the mounting plate 14 is fixed to the rectilinear barrel 3 in the posture shown in FIG. 6 as in the present embodiment, the elasticity of the flexible printed circuit board 15 at the time of assembly causes
Since it is possible to prevent a part of the protrusion from being greatly outward from the opening 3c of the straight advancement cylinder 3, the adhesive tape 16
The troublesome work of setting the folded-back portion 15a with respect to the first beam portion 14c while attaching is eliminated, and the assembling property is also improved. Further, even when the flexible printed circuit board 15 can be assembled only in the telephoto state for the convenience of work, the assembling property is improved because the folding portion 15a can be easily positioned.

Although the present invention has been described above with reference to the exemplary embodiments, the present invention should not be construed as being limited to the above-described exemplary embodiments, but it goes without saying that appropriate modifications and improvements are possible. is there. For example, the mounting plate 14 may be made of metal or resin, may be a bent wire part, or may be a part of the rectilinear barrel 3. Further, instead of the adhesive tape 16, a plate member made of metal or resin may be attached to the rectilinear barrel 3 by a method such as screwing. Further, instead of attaching the flexible printed wiring 15 to the straight-ahead tube 3,
It may be attached to the straight guide ring 6. The present invention can be applied not only to the three-stage extension zoom lens barrel but also to the two-stage extension zoom lens barrel and the multi-stage extension zoom lens barrel having four or more stages.

[0032]

According to the present invention, it is possible to provide a zoom lens barrel capable of suppressing abnormal noise, vibration, peeling of wiring, and the like.

[Brief description of drawings]

FIG. 1 is a sectional view of a zoom lens barrel according to an embodiment.

FIG. 2 is a sectional view of the lens barrel according to the present embodiment when the lens barrel is retracted (completely retracted).

FIG. 3 is a perspective view showing a part of a rectilinear barrel 3 cut away.

FIG. 4 is a view of the straight advancement cylinder 3 as seen in the direction of arrow VI in FIG.

FIG. 5 is a cross-sectional view of a zoom lens barrel that is a comparative example.

FIG. 6 is a cross-sectional view of the zoom lens barrel of the present embodiment shown in a state of being compared with a comparative example.

[Explanation of symbols]

1 Helicoid member 2 rotating cylinders 3 straight barrel 4 cam barrel 5 drive pins 6 Straight guide tube 7 front cylinder 8 Shutter unit 9 First lens group 10 Second lens group 11 Second lens frame 12 First lens frame 13 Drive axis 14 Mounting plate 15 Flexible printed wiring 16 Adhesive tape

Claims (4)

[Claims] 1. A fixing member attached to a camera body, a first tube movable in the optical axis direction with respect to the fixing member, and a predetermined drive unit, and an optical axis with respect to the first tube. A second tube movable in a direction, a flexible wiring extending from at least the drive unit to the fixing member, and an attachment unit that attaches the flexible wiring to the first tube. When extending from the fixing member toward the drive unit in the optical axis direction, the mounting member has at least one turn-back portion, and the attachment means includes a first beam portion sandwiched between the turn-back portions and the first beam. A second beam portion that is provided closer to the camera body than the portion and that supports the flexible wiring on the side closer to the optical axis. 2. A cam barrel that is movable in the optical axis direction with respect to the first barrel is provided, and the second barrel is movable in the optical axis direction with respect to the cam barrel. The zoom lens barrel according to claim 1, wherein: 3. The zoom lens barrel according to claim 1, wherein the mounting means is a plate member provided with the first beam portion and the second beam portion. 4. The zoom lens barrel according to claim 3, wherein the plate member is arranged in an opening formed in a peripheral surface of the first barrel and is fixed by a tape.