JPH07181535A - Lens barrel - Google Patents

Abstract

PURPOSE:To prevent the influence of vibration, etc., from respective mechanism parts, to prevent malfunction, to improve the assemblability of the respective parts of a lens barrel and workability and to reduce cost by constituting a fixed member constituting the lens barrel so that it may be divided into plural units. CONSTITUTION:The part which is the fixed member constituting the lens barrel E is divided into plural units 5 to 7 such as a fixed barrel 10, a 1st fixed barrel part 31, and a 2nd fixed barrel part 43, the units are integrally connected by screwing, etc., so that the lens barrel 1 is formed. A focusing mechanism part 2, an image blurring preventing mechanism part 3 consisting of a shake preventing optical system L3 and an image blurring preventing driving mechanism 30, and a shake detection sensor part 4 consisting of a shake detection sensor 40 are respectively and individually assembled and disposed in the respective units 5 to 7. Thus, the direct influence of the vibration caused by the actuation of each driving part and the vibration caused by the actuation of an actuator itself in each driving part exerted on the sensor 40 is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel which is detachably attached to, for example, a single-lens reflex camera or the like,
In particular, the present invention relates to a lens barrel including a shake detection sensor that detects image shake due to hand shake and the like, a shake prevention optical system that prevents this shake, and an image shake prevention mechanism unit including an image shake prevention drive mechanism that drives this.

[0002]

2. Description of the Related Art For example, in an interchangeable lens barrel which is detachably attached to a single-lens reflex camera, a zooming mechanism for variably adjusting a focal length of a photographing lens optical system from a telephoto lens to a wide-angle lens, and a focusing of an object. An automatic AF mechanism (autofocus mechanism) and the like are incorporated. Particularly, in recent lens barrels, an image blur prevention mechanism for compensating for a camera shake of a photographer has also been incorporated, and thus it is remarkably multifunctional.

In the lens barrel provided with such an image blur preventing mechanism, various photographing lens optical systems, various driving mechanisms and control circuit sections thereof, and further, along with the above-mentioned multi-functionalization, are further provided. Sensors and the like for detecting various information have been incorporated, and for this reason, it has been demanded to effectively utilize the space in the lens barrel.

Particularly, according to this type of lens barrel, the size thereof is determined to some extent by the aperture of the photographic lens optical system incorporated therein, and it is not preferable to make it larger than necessary. Therefore, the dead space inside the lens barrel is utilized as effectively as possible, and various drive mechanisms including electric motors, control circuits such as electric circuits, and sensors are efficiently incorporated. Must be placed.

[0005]

By the way, in the lens barrel having the image blur preventing function as described above, when the shake detection sensor is incorporated in the lens barrel, the following problems occur. It was inevitable.

That is, the focusing portion such as the AF mechanism and the driving portion such as the shake prevention driving mechanism described above are generally attached to a fixed member such as a fixed barrel or a fixed barrel that is continuous with the fixed barrel in the lens barrel. Target. Further, when the shake detection sensor is incorporated in such a lens barrel, it is also attached to the fixing member.

Therefore, in such a structure, the shake occurs due to the vibration caused by the operation of the drive unit such as the focusing unit and the shake prevention drive mechanism described above, and further the vibration generated from the drive source (actuator) in each drive unit. There is a possibility that the detection sensor may detect vibrations other than the shake, which causes a malfunction of the image shake preventing mechanism.

Further, conventionally, since various mechanisms are provided for one fixing member constituting the lens barrel, there is a problem that workability such as assembly and adjustment is deteriorated and cost is increased. In consideration of such a point, it is desired to take some measures capable of solving the above-mentioned problems.

The present invention has been made in view of the above circumstances, and prevents the shake detection sensor from being affected by vibrations or the like from each mechanism portion in the lens barrel, and malfunctions in preventing image shake. It is an object of the present invention to obtain a lens barrel which can prevent the above, further improve the workability such as assembling and adjusting each portion of the lens barrel, and can also reduce the cost.

[0010]

In order to meet such a demand, a lens barrel according to the present invention is constructed by dividing a fixing member constituting the lens barrel into a plurality of units, which are integrally formed. The lens barrel is formed by connecting to the lens, and the focusing unit for focusing in the main optical system and the image shake by moving in a plane perpendicular to the optical axis of the main optical system. An image blur prevention mechanism unit including an image blur prevention optical system for preventing the image blur, an image blur prevention drive mechanism for driving the image blur prevention optical system, and a shake detection sensor for detecting a shake are arranged in separate units.

Further, in the lens barrel according to the present invention, an ultrasonic motor is used as a drive source of the focusing unit for focusing in the main optical system, and this is incorporated into the unit constituting the lens barrel together with the focusing unit. It can be arranged.

[0012]

According to the present invention, since the drive mechanism and the shake detection sensor in the focusing portion and the image blur prevention mechanism portion are separately arranged in different units, the vibration caused by the operation of each drive portion and the drive portion It is possible to suppress the direct influence on the shake detection sensor such as vibration due to the operation of the actuator itself.

Further, according to the present invention, by assembling the focusing section, the image blur prevention mechanism section, and the shake detection sensor into separate units constituting the lens barrel, the assembly of the individual mechanism sections and the like can be performed. Adjustment work becomes easy.

Further, according to the present invention, by incorporating the ultrasonic motor as the driving source of the focusing unit in the same unit as the focusing unit, the structure is simplified,
It is possible to improve the efficiency in using the space.

[0015]

1 and 2 show an embodiment of a lens barrel according to the present invention. In these drawings, in this embodiment,
A case where the present invention is applied to an interchangeable lens barrel 1 which is detachably provided in a single-lens reflex camera as a lens barrel will be described.

Here, in this embodiment, as the lens barrel 1, as is apparent from FIG. 1, a focusing mechanism by MF (manual focus) or AF (autofocus) for performing focusing in the main optical system. 2 shows a case where an image blur prevention mechanism 3 for preventing image blur due to a camera shake of a photographer, a blur detection sensor unit 4 for detecting the image blur situation, and the like are incorporated.

More specifically, this lens barrel 1 is
A lens barrel front assembly 5 that is a focusing unit that incorporates a focusing mechanism 2 capable of AF / MF, a lens barrel intermediate assembly 6 that is an image stabilization mechanism unit that incorporates an image blur prevention mechanism 3, and a shake. The detection sensor section 4 and the like are incorporated, and the rear end portion is composed of a lens barrel rear assembly 7 which is a shake detection sensor section unit detachably attached to the camera body side (not shown).

The lens barrel 1 also includes a first lens group L1, a second lens group L2, and a third lens group L1 as a photographing lens optical system.
The group lens L3 is provided. Here, the first group lens L1
Is a fixed-side lens located at the front end of the lens barrel 1, the second lens unit L2 is a focusing lens unit that is supported in the lens barrel 1 so as to move forward and backward in the optical axis direction, and the third lens unit L3 is a focusing lens unit. The X axis in the plane orthogonal to the optical axis I,
It is an image blur preventing lens group that is moved in the Y-axis direction and prevents image blur of a subject image on the film imaging surface due to camera shake or the like.

The lens barrel front assembly (hereinafter referred to as focusing unit) 5 is a fixed barrel 1 as a lens barrel fixing member.
0, and the lens holding frame 11 on the tip side of the fixed barrel 10
Further, the first lens group L1 is held.

Further, in the fixed cylinder 10, each member constituting the focusing mechanism 2 is incorporated and arranged in an inner peripheral portion of the fixed cylinder 10 near the intermediate assembly (hereinafter referred to as a shake prevention mechanism unit) 6. That is, in this fixed cylinder 10,
An outer peripheral portion of the moving barrel 12 is fitted and held so as to be movable back and forth in the optical axis direction (I), and a lens frame 13 for holding the second lens group L2 is provided on the rear end side of the moving barrel 12. .

Further, on the outer peripheral portion of the fixed barrel 10 on the front end side, a rotary barrel 14 serving as a focus ring for moving the second lens group L2 forward and backward is fitted on the outer side of the fixed barrel 10. It is rotatably provided as a mounted rotary cylinder member. When the rotating barrel 14 rotates, the moving barrel 12 moves in the optical axis direction, and in conjunction with this, the second lens group L2 in the lens frame 13 moves for focusing. The rotating barrel 14 is a portion that serves as an MF ring that allows the second group lens L2 to be MF-operated by being manually rotated in the MF mode as described later. Of course, even in the AF mode, it is rotated with the rotation of the AF drive source.

In addition, on the outer peripheral portion of the above-mentioned moving cylinder 12,
Interlocking pins 15 and 16 are erected vertically. The interlocking pin 15 is projected in the radial direction through the clearance portion of the fixed barrel 10 and engages with the spiral guide groove 15a provided in the rotating barrel 14, and the interlocking pin 16 is formed on the inner peripheral surface of the fixed barrel 10. It is well known that the linearly keyed guide groove 16a is engaged to perform a required focusing operation. Further, the rotating barrel 14 is configured to be rotatable in a state in which the movement in the optical axis direction is restricted by the engagement of the engaging pin 10a of the fixed barrel 10 with the annular groove.

A segment gear 14a is formed on the inner periphery of the rear end portion of the rotating cylinder 14, and the segment gear 1
4a has a transmission gear 18 that is allowed to move in the axial direction by spline engagement or the like and is connected in the rotation direction on the power transmission shaft portion 17 to which rotational power is transmitted from the camera body side by the transmission shafts 17a and 17b. It is meshed. And
In the focusing mechanism section 2 having such a configuration, the transmission gear 18 of the power transmission shaft 17 is rotated in a meshed state as shown in FIG. 1, and the rotary cylinder 14 is rotated via the segment gear 14a meshed with this. Then, the moving cylinder 1
The second lens unit L2 for focusing is set to A
The focusing operation is performed by F.

Reference numeral 19 in the drawing denotes an MF / AF switching ring which is arranged on a part of the outer peripheral portion of the fixed barrel 11 so as to be able to perform a slide switching operation in the optical axis direction. A switching lever portion 18 extending from a part of a transmission gear 18 axially movably supported on 17b.
a is continuously provided. And, this switching ring 19 is MF
When the transmission gear 18 is switched to the side and the transmission gear 18 is moved in the axial direction on the transmission shaft 17b to disengage from the segment gear 14a, the rotary cylinder 14 can be separated from the AF drive source. By manually rotating the rotating barrel 14 in this state, the second lens group L2 for focusing can be operated for MF focusing.

Although not shown in the drawing, the inside of the concave portion formed by the small diameter portion 10b of the fixed cylinder 10 in which the rotary cylinder 14 is fitted to the outside in the front assembly 5 is omitted. , CPU
A circuit mounting portion 20 formed of a printed circuit board (FPC board) on which various electric components including the above are mounted is appropriately installed in the entire circumference or a part of the small diameter portion 10b.

In this embodiment, a part of the FPC board which is the above-mentioned circuit mounting portion 20 is extended to the image blur prevention drive unit unit 6 side in the lens barrel 1 as will be described later, and this extension is performed. The connection portion with another FPC board provided at the installation end includes an image blur prevention mechanism 3 disposed in the unit 6, and a shake detection sensor in a lens barrel rear assembly (hereinafter referred to as a shake detection sensor unit) 7. It is designed to be wire-connected to the section 4 and the like.

In the lens barrel 1 described above, the image blur prevention mechanism unit 6 includes an image blur prevention lens (third group lens L3) constituting the image blur prevention mechanism unit 3 and an image blur prevention driving the same. The drive mechanism 30 (only a part of which is shown) is incorporated, and the shake detection sensor unit unit 7 continuously provided continuously to the rear end side of the lens barrel includes a board on which the shake detection sensor 40 is mounted. Sensor mounting part 4
1 is installed and arranged. Further, the diaphragm mechanism unit 42 is provided on the inner side of the front end of the shake detection sensor unit 7.
Is provided.

Incidentally, in each of these units 6 and 7,
F for connecting each electric circuit component and control component
Wiring means such as a PC board is attached, and these are electrically connected to the main FPC board on the focusing unit 5 side and the like in a partial space (not shown) on the outer peripheral side of the unit 6 which is an intermediate assembly. It is designed to be connected by wiring.

Further, the transmission shafts 17b, 17a and the like which constitute the drive transmission shaft portion 17 are also disposed in these units 6, 7 so as to be appropriately supported.

According to the present invention, as described above, the portion of the lens barrel 1 that serves as the fixing member of the lens barrel 1 is the fixed barrel 10, the first fixed barrel portion 31,
The lens barrel 1 is formed by dividing the unit into a plurality of units 5, 6, 7 like the second fixed barrel 43, and integrally connecting these by screws or the like. I am configuring.

Then, for each of these units 5, 6 and 7, the focusing mechanism 2 and the shake prevention optical system L3 are provided.
And the image blur prevention mechanism section 3 by the image blur prevention drive mechanism 30 and the shake detection sensor section 4 by the shake detection sensor 40,
Each of them is separately incorporated and arranged.

According to this structure, the drive mechanism in the focusing mechanism section 2 and the image blur prevention mechanism section 3 and the shake detection sensor 40 are provided in different units 5, 6, respectively.
By arranging them separately in 7, it is possible to suppress the direct influence on the shake detection sensor 40, such as the vibration due to the operation of each drive unit and the vibration due to the operation of the actuator itself in each drive unit. . Therefore, the accuracy of the shake detection by the sensor 40 can be improved, and the shake prevention effect by the prevention mechanism section 3 can be exerted.

Further, the focusing mechanism section 2, the image blur prevention mechanism section 3, and the shake detection sensor section 4 are fixed members (fixed barrel 10, first barrel) of the respective units 5, 6 and 7 constituting the lens barrel 1. Fixed tubular portion 31, second fixed tubular portion 4
Since it is provided in 3), the individual mechanism parts can be assembled individually and the assemblability can be improved. In addition, adjustment in each part in that state can be performed, which is excellent in terms of adjustment workability and integrated. It is easy to do, and there are few product variations,
Cost reduction can also be achieved.

Particularly, in such a structure, the lens barrel 1
Since it is divided into three units, front, middle, and rear, the units 5, 6, and 7, it is extremely easy and reliable to pre-assemble and individually assemble and adjust each unit. The lens barrel 1 is constructed only by assembling and integrating the whole.

FP in each unit 5, 6, 7
It is possible to communicate with the tool by appropriately pressing the FPC connection portion of the adjustment tool or the communication tool against the connection means such as the C board, and the adjustment can be performed individually in an assembled state. it can. In particular, the position of the shake detection sensor 40, which has a great influence on accuracy and the like, can be appropriately and reliably performed, and the effect of preventing shake is great.

FIG. 2 shows another embodiment of the lens barrel according to the present invention. In this embodiment, an ultrasonic motor is used as a drive source for the focusing mechanism section 2 for focusing in the main optical system. The case where 50 is used is shown.

Here, such an ultrasonic motor 50 is
As shown in FIG. 2, the annular stator 51, the stator piece 52 located in the outer annular space thereof, and the stator piece 52 are in contact with the side surface and mesh with the segment gear 14a of the rotary cylinder 14. Rotor 5 having a gear part
3 and 3.

In such an ultrasonic motor 50, the stator 51 is fixedly supported by the fixed barrel 10 during AF, and the rotor 53 is rotatable with respect to the stator 51 and the stator piece 52. On the other hand, during MF, the rotor 53 is immovable with respect to the stator 51 and the stator piece 52, and the stator 51 is rotatable with respect to the fixed cylinder 10. It is well known that this is due to the friction coefficient between the members and the engagement relationship between the members when energized and de-energized.

Further, since the ultrasonic motor 50 as described above is small in size and quiet in operating sound, and has an annular shape as a whole, it is possible to achieve high efficiency in assembling into the lens barrel 1 and, moreover, the above-mentioned rotation. There is an advantage that a clutch for switching between AF and MF is unnecessary due to the connection relationship.

When the ultrasonic motor 50 as described above is used,
In addition to the advantages of the above-described embodiment, the lens barrel 1
By assembling and disposing the focusing mechanism section 2 in the unit 5 constituting the lens barrel, the overall structure of the lens barrel is simplified, the efficiency in utilizing the space in the lens barrel is improved, the assemblability of the entire lens barrel, and the adjustment work in each part. Improve sex,
It has advantages such as cost reduction.

The present invention is not limited to the structure of the embodiment described above, but the shape, structure, etc. of each part of the lens barrel 1 can be changed as follows.
It will be easily understood that various modifications can be considered, as appropriate modification and change are possible.

Further, in the above-described embodiments, the case where the present invention is applied to the lens barrel 1 mounted on a single-lens reflex camera has been described, but the present invention is not limited to this, and image blur prevention is prevented in the lens barrel of various cameras. It can be applied to those having a mechanism to exert the effect.

[0043]

As described above, according to the lens barrel of the present invention, the fixing member constituting the lens barrel is divided into a plurality of units, and these are integrally connected. A lens barrel is formed, and a focusing unit that performs focusing in the main optical system and an anti-shake optical that moves in a plane perpendicular to the optical axis of the main optical system to prevent image shake The system and the image blur prevention mechanism unit including the image blur prevention drive mechanism for driving the system and the shake detection sensor for detecting the shake are arranged in separate units, respectively, so that the structure is simple. Instead, various excellent effects listed below are exhibited.

That is, according to the present invention, the driving mechanism in the focusing unit and the image blur prevention mechanism unit and the shake detection sensor are separately arranged in different units, so that the vibrations and the driving by the operation of the respective drive units are increased. It is possible to reduce the fact that the shake detection sensor directly receives and detects the vibration and the like due to the operation of the actuator itself in the section, the accuracy in detecting the shake is improved, and the shake prevention effect can be exerted.

Further, according to the present invention, the focusing section, the image blur prevention mechanism section, and the shake detection sensor are provided in separate units constituting the lens barrel, so that the individual mechanism sections are individually assembled. In addition to being able to improve the assembling ability, it is also possible to make adjustments in each part in that state, which is also excellent in terms of adjustment workability and easy to integrate.
In addition, there are advantages such as less product variation and cost reduction.

According to the lens barrel of the present invention,
An ultrasonic motor is used as a driving source for the focusing unit that performs focusing in the main optical system, so this ultrasonic motor is focused on the unit that forms the lens barrel, despite the simple structure. By arranging them together with the parts, the overall structure can be simplified, the efficiency in using the space in the lens barrel can be improved, the assemblability of the entire lens barrel, the adjustment workability of each part, etc. can be improved, and the cost can be reduced. Plays the advantage of.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional side view of an entire lens barrel showing an embodiment of the lens barrel according to the present invention.

FIG. 2 is a schematic vertical sectional side view showing another embodiment of the lens barrel according to the present invention.

[Explanation of symbols]

 1 Lens barrel 2 AF / MF capable focusing mechanism 3 Image blur prevention mechanism 4 Shake detection sensor unit 5 Lens barrel front assembly (focusing unit unit) 6 Lens barrel middle assembly (Image blur prevention mechanism unit) 7 Rear barrel assembly (shake detection sensor unit) 10 Fixed barrel (fixed member) 11 Lens holding frame 12 Moving barrel 13 Lens frame 14 Rotating barrel 15 Interlocking pin 16 Interlocking pin 17 Power transmission unit 18 Transmission gear 19 AF / MF switching ring 20 Circuit mounting part 30 Image blur prevention drive mechanism 31 First fixed cylinder part (fixed member) 40 Shake detection sensor 41 Sensor mounting part 42 Aperture control mechanism part 43 Second fixed cylinder part (fixed member) 50 Ultra Sound wave motor L1 First lens group L2 Second lens group L3 Third lens group (anti-shake lens) I Optical axis

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G03B 3/10 13/34

Claims (2)

[Claims] 1. A focusing unit for focusing in a main optical system, an anti-shake optical system for moving an image in a plane perpendicular to an optical axis of the main optical system to prevent image shake, and an anti-shake optical system. In a lens barrel including an image blur prevention mechanism unit configured to drive an image blur prevention drive mechanism and a shake detection sensor for detecting a blur, a fixing member forming the lens barrel is separated into a plurality of units. The lens barrel is formed by integrally connecting these components, and the focusing unit, the image blur prevention mechanism unit, and the shake detection sensor are provided in separate units. Lens barrel characterized by. 2. The lens barrel according to claim 1, wherein an ultrasonic motor is used as a drive source for the focusing unit.