JPH07120649A - Lens barrel - Google Patents

Abstract

PURPOSE:To provide a radially small-sized lens barrel capable of effectively utilizing the space. CONSTITUTION:The lens barrel has a photographing optical system formed out of a first group lens 12, a second group lens 13, a third group lens 14, and a fourth group lens 15, a substantially disc-like diaphragm mechanism having a diaphragm blade 22 supported by a diaphragm case 20 having an aperture for passing the object light of the photographing optical system almost in the center, a stepping motor 24 for driving the diaphragm mechanism which is arranged on the outside from the aperture on the optical axial end face of the diaphragm, a third lens frame 7 prohibited to relatively rotate around the optical axis, arranged on the outside of the diaphragm mechanism, and having a housing hole 7a for housing the part protruded to the outside from the outer diameter of the diaphragm mechanism of the stepping motor 24, and a first and second group lens frame 8 having a housing hole 8a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel, and more particularly to a lens barrel having a photographing optical system and an exposure device.

[0002]

2. Description of the Related Art Conventionally, various types of lens barrels have been proposed for incorporating an exposure apparatus and a motor for driving the exposure apparatus.

As an example of such a device, for example, in Japanese Patent Application Laid-Open No. 61-270737, a diaphragm / shutter provided immediately after the main optical system is advanced along the optical axis together with the main optical system. In a camera equipped with a photographing lens whose focal length can be switched by inserting a sub-optical system on the optical axis behind the aperture / shutter,
A lens barrier that covers the front part of the main optical system is provided so as to be openable and closable, and a shutter drive device that drives the diaphragm / shutter is provided between the lens barrier and the diaphragm / shutter to surround the main optical system. ,further,
An outer cylinder having a circular cross section surrounding at least the lens barrier and the main optical system is provided except for the sub optical system, and when the sub optical system is inserted on the optical axis, the outer cylinder is at least the shutter drive device. A bifocal camera configured to project and move to the outside of the camera body to a position surrounding a drive unit is described. A stepping motor, which is a driving device that drives the shutter that also serves as the diaphragm, and circuit components for controlling the driving of the stepping motor are arranged on a ring-shaped shutter control circuit board.

Another example is Japanese Patent Laid-Open No. 63-242.
In Japanese Patent Laid-Open No. 31-31991, an exposure apparatus main body incorporating a portion required for exposure such as an optical path hole centered on the optical axis and a light shielding blade for opening and closing the optical path hole, and an end surface of the exposure apparatus main body is disclosed. A light-shielding blade drive motor protruding in parallel with the optical axis at a position eccentric to the optical axis, and a projection motor provided at the end surface of the exposure apparatus main body at a position where the light-shielding blade drive motor does not exist. An electric exposure apparatus comprising: a protrusion having a protrusion length that is at least not longer than the protrusion length of the blade drive motor.

[0005]

However, the one disclosed in Japanese Patent Laid-Open No. 61-270737 has a problem in that the space occupied by the members such as the stepping motor and the stepping motor control circuit in the radial direction is different. , The shutter control circuit board on which these parts are placed needs to match the external shape with the part that occupies the most space in the radial direction, and the outer diameter of the lens barrel and the like located outside the shutter control circuit board is also determined by this shutter control circuit board. As a result, the space was not used efficiently.

In the above-mentioned Japanese Patent Laid-Open No. 63-24231, exactly the same is true, among the members such as the light-shielding blade drive motor and various electric circuits installed on the same end face as the exposure apparatus main body, they are occupied in the radial direction. The size of the lens barrel in which this unit is incorporated is determined by the member that takes up the largest space, and the space has not been used efficiently.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lens barrel that is small in the radial direction and that can effectively use space.

[0008]

In order to achieve the above object, the lens barrel according to the present invention has a photographic optical system and an aperture at substantially the center through which the subject light of the photographic optical system passes. A disc-shaped exposure apparatus, an electric element for driving the exposure apparatus arranged outside the opening on the end face in the optical axis direction of the exposure apparatus, and an outside of the exposure apparatus And a lens frame having a housing hole for housing a portion of the electric element projecting outward from the outer diameter of the exposure apparatus.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show an embodiment of the present invention. FIG. 1 is a sectional view showing the upper half of the optical axis of the interchangeable lens of this embodiment. This lens is a medium-telephoto macro lens, and the first group lens 1 is arranged in order from the front along the optical axis O.
2, 2 group lens 13, 3 group lens 14, 4 group lens 15
Since it is possible to take close-up shots up to the same size, the extension amount is large. Also, the lens is
A floating mechanism is adopted to improve the performance in the macro area, and the number of lens frames involved in the extension is larger than that of a normal single focus lens.

As shown in FIG. 1, the fixed frame, which is immovable with respect to the camera body when the lens barrel is attached, is located at the most suitable position in terms of its function or assemblability. Second fixed frame 2, third fixed frame 3, fourth fixed frame 4 of 4
It is divided into two parts, and each is securely fixed by screws (not shown).

More specifically, a second fixed frame 2 is provided on the rear end side of the lens barrel, and the second fixed frame 2 is provided.
In addition to fixing the mount 5 mounted to the camera body main body to the rear end surface by screws (not shown), the rear frame 19 supporting the fourth group lens 15 is fixed to the inner peripheral surface side.

On the substantially inner peripheral side of the second fixed frame 2,
A fourth fixed frame 4 is provided. A first fixed frame 1 is connected to the front side of the fourth fixed frame, and a third fixed frame 3 is attached to the outer periphery of the front end of the first fixed frame 1. The first fixed frame 1 is provided with an oblique cam 1a that engages with a first roller 9 described later and a rectilinear cam 1b that engages with a second roller 10 described later.

A cam ring 55 is provided on the outer peripheral surface side of the first fixed frame 1. In this cam ring 55,
An oblique cam 55a that engages with a first roller 9 described later is provided. Also, at the rear end of the cam ring 55,
Magnet 35 magnetized with a fine pitch magnetic scale
A plurality of magnetoresistive elements 36 are pressure-bonded to the magnet 35 at appropriate intervals. With such a configuration, the rotation amount of the cam ring 55 is detected. Further, planet gears 33 are rotatably attached to the circumferential surface of the cam ring 55 at three locations along the circumferential direction.

In the ring-shaped space between the cam ring 55 and the fourth fixed frame 4, a ring-shaped vibration wave motor for autofocusing is arranged.

That is, the stator 28 of the vibration wave motor is fixed to the fourth fixed frame 4 by being restricted in rotation, and the generated vibration wave causes the rotor 29 arranged in front of the stator 28 to rotate. It is like this.

A gear frame 30 is provided on the front side of the rotor 29. The gear frame 30 integrally rotates with the rotor 29, has a gear carved on the outer periphery thereof, and has a ball groove on the front end face.
When the gear frame 30 is rotated, the balls 32 are inserted between the gear frame 30 and the ball ring 31, which is fixed to the front surface of the fourth fixed frame 4 and is also provided with ball grooves. The slidability of is improved.

The cam ring 55 is attached to the gear frame 30.
The planetary gear 33 attached to is meshed. The planetary gear 33 meshes with the operation ring 34 on the outer side thereof.

That is, on the outer peripheral side of the cam ring 55, there is provided an operation ring 34 which is manually rotated by the operator during manual focusing, and at the rear end portion of the inner peripheral surface of the operation ring 34. An internal gear 34a is engraved and meshes with the planet gear 33. The operation ring 34 is non-rotatably fixed by a lock mechanism (not shown) in the use state of auto focus, and is set to be rotatable in the use state of manual focus. It is supposed to be done.

A main flexible printed circuit board 39 is fixed to the inner peripheral side of the fourth fixed frame 4, and a lens CPU is mounted on the main flexible printed circuit board 39.
37 is attached.

On the inner peripheral surface side of the first fixed frame 1,
An intermediate frame 6 is provided, and the intermediate frame 6 is the first frame.
Oblique cam 1a of fixed frame 1 and oblique cam 5 of cam ring 55
The first roller 9 projecting from the rear end portion of the peripheral surface thereof is moved by 5a, whereby the feeding operation is performed while rotating. In addition, the intermediate frame 6 has an oblique linear cam 6 for feeding out a first and second lens group frame 8 to be described later.
a and a slanted curve cam 6 for extending the third group lens frame 7
b is provided.

A third group lens frame 7 as a frame member is provided on the inner peripheral surface side of the intermediate frame 6, and on the rear end side of the peripheral surface.
The second roller 10 is provided so as to project, and a straight cam 7d that engages with a third roller 11, which will be described later, is provided on the slightly front side thereof. The third group lens frame 7 is provided with a storage hole 7a (see FIGS. 1 and 4) for mounting a stepping motor 24, which will be described later, and a transformer 38 for boosting, which is an electric element. 2b (see FIGS. 2 and 4), and a storage hole 7c (FIGS. 3 and 4) for arranging the flexible flexible printed circuit board 40 and the motor driver 51 which is an electric element mounted on the circuit board 40. (See 4)
Are drilled respectively. The third group lens frame 7 performs a rectilinear advancing operation by the second roller 10 being fed in the front-rear direction by the slanting curve cam 6b of the intermediate frame 6 along the rectilinear cam 1b of the first fixed frame 1. Is. A second middle frame 18 that supports the third lens group 14 is fixed to the rear end of the third lens group frame 7.

On the inner peripheral surface side of the third group lens frame 7, there are provided first and second group lens frames 8 as frame members. The front frame 16 supporting the first group lens 12 is arranged on the front side, and the second group lens is formed. A first middle frame 17 that supports 13 is fixed to the rear side.
A storage hole 8a for disposing the stepping motor 24 is formed in the peripheral surface of the first and second lens groups 8 (see FIGS. 1 and 4).
And a storage hole 8b for disposing the boosting transformer 38.
(See FIGS. 2 and 4), a retractable flexible printed circuit board 40, and a housing hole 8c for disposing a motor driver 51 mounted on the circuit board 40 (see FIGS. 3 and 4).
Are formed respectively, and they are respectively located on the inner peripheral surface side which is substantially the same position on the peripheral surfaces of the housing holes 7a, 7b, 7c of the third group lens frame 7. Further, a third roller 11 is projectingly provided at the rear end portion of the peripheral surface of the first and second lens group frames 8, and the third roller 11 is intermediate along the straight-moving cam 7d of the third lens group frame 7. The first and second group lens frames 8 are fed by being fed in the front-rear direction by the diagonal linear cam 6a of the frame 6.
Is for performing a straight-advancing operation.

Here, the first group lenses 12 and 2 as described above.
How the group lens 13, the third group lens 14, and the fourth group lens 15 move in the optical axis direction by the focusing operation will be described with reference to FIG. 7. In this medium-telephoto macro lens, the first-group lens 12 is used when the focus is moved from the infinity position to the closest position where 1: 1 shooting at equal magnification is possible.
And the second group lens 13 extends for 50.4 mm, and the third group lens 14 forms the first group and second group lens 1
For example, a delay of 2 and 13 is performed to extend the lens by 46.4 mm, and the fourth group lens 15 is kept stopped.

A diaphragm mechanism as an exposure device is provided between the first lens group 12 and the second lens group 13. That is, the diaphragm case 20 is attached to the rear end side of the first and second lens groups 8 and the diaphragm blades 22 are held therein by the blade retainer 23, and further, the diaphragm blades 22 are attached. The arrow wheel 21 for rotating is provided.

A third gear 21a (see FIG. 4) is engraved on a part of the peripheral surface of the arrow wheel 21 over a certain angular range so that the rotation from the stepping motor 24 can be transmitted. There is.

That is, the stepping motor 24 has a substantially cylindrical shape, and the first gear 25 is attached to the tip of the motor shaft 24a protruding from the stepping motor 24 on the rear side of the optical axis so as to rotate integrally. ing. The first gear 25 meshes with a second gear 26, and the second gear 26 is rotatably supported by a gear shaft 27 protruding from the front end surface of the diaphragm case 20. Further, the second gear 26 is the third gear 21a of the arrow wheel 21.
Is engaged with the stepping motor 2
The driving force of No. 4 is transmitted to the third gear 21a,
Is designed to rotate.

Next, details of the periphery of the diaphragm unit will be described with reference to FIGS. 4, 5 and 6. The front frame 16 and the first group lens 12 are not shown in FIG. As described above, the stepping motor 24 has a substantially cylindrical shape and requires a large space in the radial direction (direction perpendicular to the optical axis) within the lens barrel, so that the inner diameter of the first and second lens groups frame 8 is increased. It is impossible to arrange the entire stepping motor 24 in the donut-shaped space sandwiched between 8d and the outer diameter 16a of the front frame 16.

Therefore, about half of the outside of the stepping motor 24 with respect to the optical axis O is the first and second lens groups frame 8.
It is arranged so as to project outward from the inner diameter 8d of the above and reach near the inner diameter of the intermediate frame 6. Then, the above 1, 2
In the group lens frame 8 and the third group lens frame 7, at the position of the protruding stepping motor 24, the storage hole 8 is formed as described above.
a and 7 a are respectively formed so that the first, second, and third lens frames 8 and 7 do not interfere with the stepping motor 24.

As described above with reference to FIG. 7, the first lens group 12 and the second lens group 13 are designed to extend by about 4 mm more than the third lens group 14, so that the first lens group 12 is used. Also, the first and second group lens frames 8 holding the second group lens 13 are also extended by about 4 mm more than the third group lens frame 7. Therefore, the storage hole 7a of the third group lens frame 7 is provided with an extra front end surface 7a 'so as to absorb the extra feed amount.

The stepping motor 24 is fixed to the motor fixing shaft 42 with a motor first fixing screw 43 sandwiching the motor fixing plate 41, and the motor fixing shaft 42 is further connected to the first and second lens groups 8 It is fixed to the first and second lens group frames 8 by inserting it into a hole (not shown) and screwing a second fixing screw (not shown) from the rear side.

Further, as shown in FIG. 2, the lens barrel is provided with a step-up transformer 38 for driving a vibration wave motor composed of a stator 28, a rotor 29, etc. In this interchangeable lens, as shown in FIG. 4, two transformers 38 of the same type are used. As shown in FIG. 4, the step-up transformer 38 is mounted on an arc-shaped hard printed circuit board 45 at a position substantially opposite to the stepping motor 24 on the substantially same circumference centered on the optical axis O. It is mounted and arranged.

Unlike the other electronic parts, the boosting transformer 38 has a very large volume. Therefore, like the stepping motor 24, the first and second group lens frames 8 are provided.
It is not possible to arrange the whole of it in the donut-shaped space between the inner diameter 8d of the and the outer diameter 16a of the front frame 16.

Therefore, the protruding portion 45a having an outer diameter reaching a portion near the inner diameter of the intermediate frame 6 on a part of the outer periphery of the rigid printed circuit board 45.
Is formed as shown in FIG. 4, and the boosting transformer 38 is mounted therein.

At this time, as described above, the third group lens frame 7 and the first and second group lens frames 8 are provided with the storage holes 7b and 8b, respectively, whereby the third group lens frames 7 and 1 are formed. , The second group lens frame 8 is prevented from positional interference with the projecting portion 45a and the boosting transformer 38. For the same reason that the front end surface 7a 'of the storage hole 7a is provided, the front end surface 7b' of the storage hole 7b of the third group lens frame 7 is notched toward the front side of the optical axis in consideration of a margin. .

Further, the protruding portion 45 of the rigid printed board 45
The parts other than a are set inside the inner diameter 8d of the first and second lens groups 8.

In addition to the boosting transformer 38, the hard printed circuit board 45 is mainly an electronic component of a power system circuit for driving the vibration wave motor, such as an inductor 46, a power MOS transistor 47, and a capacitor 48.
Etc. are mounted on both sides. That is, the rigid printed circuit board 45 is fixed on the diaphragm case 20 at an appropriate interval, so that the rigid printed circuit board 45 can mount electronic components on both sides thereof.

Further, as shown in FIG. 3, the lens barrel is provided with a telescopic flexible printed circuit board 40, and the stepping motor 24, the boosting transformer 38, etc. are provided on the rear side of the lens barrel. Placed lens C
The main flexible printed circuit board 39 on which electronic components such as the PU 37 are mounted is electrically connected.

That is, the elastic flexible printed board 40 is fixed to the aperture case 20 whose front end is fixed to the first and second lens groups 8 and the rear end to the fourth fixed frame 4. It is electrically connected to the main flexible printed circuit board 39 (see FIG. 1). The flexible printed circuit board 40 is provided with a U-shaped bent portion 40 in the middle thereof in order to correspond to the amount of extension of the first and second lens group frame 8 of about 50.4 mm.
a (see FIG. 3) is provided, and the first and second group lens frames 8 are provided.
The bent portion 40a corresponds to the guide plate
It is designed to move back and forth along the line 9.

More specifically, the expandable flexible printed circuit board 40 passes through the inside of the fourth fixed frame 4 from the connecting portion with the main flexible printed circuit board 39, and is double-sided on the guide plate 49 fixed to the first fixed frame 1. After being fixed by tape or the like and folded back by 180 ° at the tip of the guide plate, the pressing plate is fixed to the diaphragm case 20 with screws or the like by changing the direction by 180 ° to the front side again at the bent portion 40a. It is fixed to 50 with tape on both sides.

The bent portion 40a of the expandable flexible printed circuit board 40 moves back and forth in accordance with the extension of the first and second lens groups 8 and the like. If the radius of curvature is too small, the resistance during this movement is increased. Therefore, it is desirable that the radius of curvature of the bent portion 40a be as large as possible. Therefore, since a space in the radial direction (direction perpendicular to the optical axis) is required like the stepping motor 24, the boosting transformer 38, etc., as shown in FIG. 4 and FIG. Storage holes 8c and 7c are formed in the third group lens frame 7 at the positions where the expandable flexible printed circuit board 40 and the guide plate 49 are present, and the space in the radial direction (direction perpendicular to the optical axis) is as wide as possible. By taking this, the radius of curvature of the bent portion 40c is made as large as possible.

The housing holes 8c and 7c are formed so that the first and second lens groups frame 8 and the third lens group frame 7, the guide plate 49 and the flexible flexible printed circuit board 40 can be inserted or moved in the optical axis direction. The second group lens frame 8 and the third group lens frame 7 are respectively extended to the rear end faces, and the end faces 7c ′, 8
c ′ is formed (see FIG. 5).

As shown in FIGS. 4 and 6, the flexible flexible printed board 40 is divided into three branches, namely, a first branch 40b, a second branch 40c, and a third branch 40d at the front end portion thereof. ing. Since the front end of the elastic flexible printed circuit board 40 has a space for branching the branches 40b, 40c, 40d, the stepping motor 2 is provided there.
By mounting the motor driver 51 for four drives, the space is effectively used.

The first branch 40b of the three branches 40b, 40c, 40d is provided with a conductive pattern exposed portion (not shown) at the tip thereof, and the stepping motor 2
It is electrically connected to four terminals protruding from the peripheral surface of No. 4 by soldering.

The stretchable flexible printed circuit board 40 is
In the direction of the second branch 40c, the rigid printed circuit board 45
Is bent in a direction perpendicular to the optical axis by a bending line 40e to a surface opposite to the surface on which the step-up transformer 38 is mounted, and electrically connected to the conductive pattern of the hard printed board 45 by soldering. Has been done.

In the flexible flexible printed circuit board 40, in the direction of the third branch 40d, after a bent portion 40f bent in a direction parallel to the optical axis is provided in the middle, conductive exposure in an arc shape centered on the optical axis is provided. A switch pattern portion 40g having a pattern 40h is formed. This is because the contact 52 fixed to the arrow wheel 21 shown in FIG. 4 with a screw or the like is slid on the conductive pattern 40h to expose the conductive exposed pattern 40h.
The signal of conduction / non-conduction is detected when passing through the break 40i, and is used for detecting the open position of the diaphragm.

Next, the operation of the lens barrel of this embodiment during autofocusing and manual focusing will be briefly described. At the time of autofocus, the lens CPU 37 calculates the rotation amount of the cam ring 55 based on the information from the camera body, and the stator 28 of the vibration wave motor is calculated.
An oscillating wave is generated to rotate the rotor 29. The rotor 29 rotates integrally with the gear frame 30 to rotate the planet gear 33 attached to the cam ring 55.

An internal gear 34 with which the planetary gear 33 meshes
Since the operation ring 34 having a is locked so that it cannot rotate during autofocus, the planetary gear 3
The rotation of 3 rotates the cam ring 55, and when the magnetoresistive element 36 detects a predetermined rotation amount, the vibration wave motor stops.

Next, at the time of manual focusing, the operation ring 34 is rotated by the photographer and the internal gear 34a is rotated.
The planetary gear 33 is rotated via. The planetary gear 33 meshes with the gear frame 30 on the one hand, but the gear frame 3
Since the rotor 29, which rotates together with 0, cannot rotate due to the frictional force generated between the rotor 29 and the stator 28 during manual focusing, the gear frame 30 does not rotate. Therefore, by rotating the operation ring 34, the cam ring 55 rotates.

In the interchangeable lens barrel constructed as described above, a large space is required near the front end surface of the diaphragm unit in the direction perpendicular to the optical axis direction. The diaphragm driving stepping motor 24 and the boosting transformer 38. Extending the flexible flexible printed circuit board 40 and the like, and for the portion protruding from the outer diameter of the aperture unit, by providing a housing hole in a necessary range in the lens frame located outside thereof, the housing hole is provided outside without forming a housing hole. Compared with the case where the lens frame is arranged, the space can be used very efficiently, and the outer diameter of the entire interchangeable lens barrel can be significantly reduced.

Further, in this embodiment, the third group lens frame 7 and the first and second group lens frames 8 provided with the storage holes are moved straight like the stepping motor 24, the step-up transformer 38, and the flexible flexible printed board 40 which are projected. The third group lens frame 7 and the first and second group lens frames 8 are extended.
Since the relative amount of movement of the lens in the optical axis direction is reduced to about 4 mm, the storage hole can be made to have a necessary minimum size, and the strength of the lens frame due to the provision of the storage hole can be improved. Almost no decline.

Further, as shown in FIG. 4, the stepping motor 24 and the boosting transformer 38 are arranged at positions facing each other by about 180 ° in the circumferential direction, and they are provided with a flexible stretchable flexible print. Since they are connected by the board 40, they can be easily inserted into the storage hole by bending them toward the optical axis center, and the stepping motor 24, the rigid printed board 45, and the flexible flexible printed board 40 can be squeezed. By fixing each to 20, it is possible to easily assemble.

Further, as can be seen from FIG. 4, since the hard printed circuit board 45 is arranged over a range smaller than 180 ° in the circumferential direction, the projecting portions 45a are formed in the first, second, and third lens groups. It can be easily inserted into the storage holes 8b, 7b of the frame 7.

Further, in this embodiment, the stepping motor 24 and the hard printed circuit board 4 are provided on the front end surface of the diaphragm unit.
Even if a light leak occurs in the space between the front frame 16 and the first and second group lens frames 8 due to the arrangement of the fifth frame, the space between the front frame 16 and the first middle frame 17 should be avoided. It can be expected that light rays will not easily enter the lens optical path.

Thus, according to such an embodiment, the exposure is performed on one end surface of the exposure apparatus main body such as the diaphragm or the shutter, which is generally arranged at the position where the light flux passes through the interchangeable lens barrel. In the case where actuators for driving the apparatus main body and other members such as electric parts which require a relatively large space are arranged and the members such as the actuators have a projection portion with respect to the outer shape of the exposure apparatus main body. In addition, since the housing hole is provided at a corresponding position of the frame member covering the exposure apparatus main body, and the projecting portion is housed in the housing hole, members such as actuators are Even when compared with a frame member that is not provided, the size of the outer diameter does not change so much, and it is very effective in reducing the outer diameter of the interchangeable lens barrel.
In this way, the lens barrel can be miniaturized not only in a normal lens but also in a macro lens in which the outer diameter of the lens frame tends to be large.

Although the macro lens has been described in the above embodiment, it goes without saying that the present invention can be applied to a normal lens. Further, in the above description, the one in which the diaphragm mechanism is arranged in the lens barrel has been described.
It goes without saying that the present invention can be similarly applied to a lens shutter device and the like.

[0056]

As described above, according to the present invention, it is possible to provide a lens barrel which is small in the radial direction and which can effectively utilize the space.

[Brief description of drawings]

FIG. 1 is a sectional view showing an upper half of an optical axis when a lens barrel showing an embodiment of the present invention is cut at a position of a stepping motor for driving a diaphragm.

FIG. 2 is a cross-sectional view showing the upper half of the optical axis when the lens barrel of the above-described embodiment is cut at the position of a boosting transformer.

FIG. 3 is a cross-sectional view showing the upper half of the optical axis when the lens barrel of the above embodiment is cut at a position where an elastic flexible printed circuit board is arranged.

FIG. 4 is a cross-sectional view showing the inside of a third group lens frame when the lens barrel shown in FIGS. 1, 2, and 3 is cut along the entire circumference along a cutting line AA ′.

FIG. 5 is a perspective view of the third group lens frame of the above-described embodiment as seen from the rear side of the optical axis.

FIG. 6 is a perspective view of the expandable flexible printed circuit board, the stepping motor, and the hard printed circuit board of the above-described embodiment as seen from the front side of the optical axis.

FIG. 7 is a diagram showing the movement of each lens unit in the above-described embodiment in the optical axis direction by focusing.

[Explanation of symbols]

 7 ... 3 group lens frame (frame member) 7a, 8a ... storage hole 8 ... 1, 2 group lens frame (frame member) 12 ... 1 group lens 13 ... 2 group lens 14 ... 3 group lens 15 ... 4 group lens 20 ... Diaphragm case 22 ... Diaphragm blade 24 ... Stepping motor (electrical element) 38 ... Transformer for boosting (electrical element) 40 ... Flexible flexible printed circuit board 45 ... Hard printed circuit board 51 ... Motor driver (electrical element) 55 ... Cam ring

[Procedure amendment]

[Submission date] February 24, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

A cam ring 55 is provided on the outer peripheral surface side of the first fixed frame 1. In this cam ring 55,
An oblique cam 55a that engages with a first roller 9 described later is provided. Also, at the rear end of the cam ring 55,
Magnet 35 magnetized with a fine pitch magnetic scale
Is provided, and a magnetoresistive element 36 is pressed against the magnet 35 at an appropriate interval . With such a configuration, the rotation amount of the cam ring 55 is detected. Further, planet gears 33 are rotatably attached to the circumferential surface of the cam ring 55 at three locations along the circumferential direction.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

The cam ring 55 is attached to the gear frame 30.
The planetary gear 33 attached to is meshed. The planetary gear 33 is an internal gear of the operation ring 34 on the outside thereof.
It meshes with 34a .

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction content]

More specifically, the expandable flexible printed circuit board 40 passes through the inside of the fourth fixed frame 4 from the connecting portion with the main flexible printed circuit board 39, and is double-sided on the guide plate 49 fixed to the first fixed frame 1. After being fixed by tape or the like and folded back by 180 ° at the tip of the guide plate, the pressing plate is fixed to the diaphragm case 20 with screws or the like by changing the direction by 180 ° to the front side again at the bent portion 40a. It is fixed to 50 with double-sided tape or the like.

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (4)

[Claims] 1. A photographing optical system, an exposure device having a substantially disc shape having an opening through which the subject light of the photographing optical system passes, and an end face in the optical axis direction of the exposure device. An electric element for driving the exposure apparatus, which is arranged outside the opening, and an electric element, which is arranged outside the exposure apparatus, projecting outward from the outer diameter of the electric element of the electric apparatus. A lens barrel comprising: a lens frame having a housing hole for housing a portion in which the lens barrel is housed. 2. The electric element is mounted on a printed circuit board, and the printed circuit board has an angle about an optical axis occupied by an arc portion within 180 °. Lens barrel. 3. The lens barrel according to claim 1, wherein a plurality of the electric elements are provided, and the electric elements are connected by a flexible printed board. 4. The lens frame is composed of a plurality of frame members which are fitted in a radial direction and whose relative rotation around the optical axis is prohibited, and the housing holes are formed in these frame members. The lens barrel according to claim 1, wherein: