JP2001083389A - Lens barrel provided with electric circuit package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently arrange an electric circuit package in a lens barrel constituted of a rotary barrel engaged with a fixed barrel so as to be extended to rotate and a front group lens barrel engaged with the fixed barrel and the rotary barrel so as to be extended to straight advance. SOLUTION: This lens barrel is equipped with a 1st male helicoid ring 4 helicoid-coupled with the 1st fixed barrel 1 and extended to rotate. Then, a roller 22 provided in a straight advance guiding barrel 7 held to freely turn with respect to a 2nd male helocoid ring 5 integrated with the ring 4 is engaged in the guiding groove 2a of the 2nd fixed barrel 2 integrated with the barrel 1 on its inner peripheral side so as to make the barrel 7 move in an optical axis direction. A roller 23 provided in the front group lens barrel 9 integrated with a female helicoid ring 8 helicoid-coupled with the ring 5 is engaged in the guiding groove 7a of the barrel 1 so as to make the lens barrel 9 move to straight advance, and an electric circuit package 15 is attached to the barrel 2 between the barrels 2 and 7 through a holding plate 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed barrel, a rotary barrel engaged with the fixed barrel and fed out, and a front group mirror engaged with the fixed barrel and the rotary barrel and fed straight forward. The present invention relates to a lens barrel, such as a photographic lens, including a cylinder and having an electric circuit mounted thereon.

[0002]

2. Description of the Related Art In general, in a camera system for controlling electric droplets such as AF and AE, it is necessary to communicate specific coefficients and information to the camera side with respect to a focal length and a focal position of a lens. The cylinder is provided with position detecting means for detecting information such as the current focal length and the focal position. The cylinder also processes these information, receives an instruction from the camera side, and controls each operation such as the aperture. Has circuit implementation. In view of the above, a multi-stage feeder which conventionally includes a fixed barrel, a rotary barrel that is engaged with the fixed barrel and is fed out, and a front lens barrel that is engaged with the fixed barrel and the rotary barrel and is straightly fed out. In the lens barrel described above, the electric circuit mounting is arranged on the camera body side to be fixed.

[0003]

However, none of the lens barrels as in the prior art described above has an electric circuit mounted inside the lens barrel, so that the camera body to be mounted for automatic control is limited. I was

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the conventional example, the present invention provides a fixed barrel, a rotating barrel engaged with the fixed barrel, and rotated and fed, and a linear barrel engaged with the fixed barrel and the rotating barrel to be fed straight. It is an object of the present invention to provide an efficient and low-cost lens barrel having an electric circuit mounting in a lens barrel constituted by a front group barrel.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a front lens barrel which is straight forward and a guide cylinder for moving the front lens barrel in the optical axis direction. The electric circuit package is held between the second fixed cylinder.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention as set forth in claim 1 is a first fixed cylinder and a second fixed cylinder which is integrally disposed on the inner periphery of the first fixed cylinder.
A lens constituted by a fixed barrel, a rotating barrel engaged with the first fixed barrel and rotated and fed out, and a front group barrel engaged with the first fixed barrel and the rotating barrel and straightly fed out. A lens barrel having first guide means rotatably held by the rotary barrel and movably engaged with a first guide groove provided in the second fixed barrel in the optical axis direction; A guide tube having a second guide groove which engages with a second guide means provided in the front lens barrel and movably engages the front lens barrel in the optical axis direction; An electric circuit mounting and holding means held by the second fixed barrel between the fixed barrel and the guide barrel allows an electric circuit to be provided to the second fixed barrel for guiding the extended front lens barrel. Made it possible to keep the implementation. According to the second aspect of the present invention, the electric circuit mounting / holding means has an engaging portion with the second fixed cylinder at a front end portion and a fixing portion at a rear end portion, whereby the electric circuit mounting / holding device is held on the second fixed cylinder. The method can be simplified. According to a third aspect of the present invention, there is provided the connector for connection with another printed wiring board on the electric circuit mounting, wherein the second fixed cylinder has an opening at a position where the electric circuit mounting is located. This makes it easier to perform connection work and inspection of an electric circuit mounting function, and also makes it possible to absorb the height of electric circuit components on the electric circuit and save space.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a longitudinal sectional view of the lens barrel of the present embodiment when shortened, FIG. 2 is a longitudinal sectional view of the same when it is extended, and FIG. 3 is an exploded perspective view of a main part thereof. In the figure, reference numeral 1 denotes a first fixed cylinder having a female helicoid portion 1a formed on an inner peripheral portion thereof. Reference numeral 2 denotes a second fixed cylinder, which is disposed inside the first fixed cylinder 1, has a rear end attached to a rear end opening of the first fixed cylinder 1, and further has a guide groove 2a in the optical axis direction and an opening. 2c is
A mounting holding plate mounting portion 2b is provided near the rear end. Reference numeral 3 denotes a mount, which is attached to the rear end face of the first fixed cylinder 1. Reference numeral 4 denotes a first male helicoid ring, and a male helicoid portion 4a formed on the outer peripheral surface thereof is helicoidally connected to the female helicoid portion 1a of the first fixed cylinder 1. Reference numeral 5 denotes a second male helicoid ring, the rear end of which is fixed to the rear end of the first male helicoid ring 4 at a radial interval, and is disposed on the outer peripheral side of the second fixed cylinder 2. A guide cylinder 7 to be described later is rotatably held on the front edge of the second male helicoid ring 5 by a holding plate 20. Reference numeral 6 denotes an operation ring fixed to the front end of the first male helicoid ring 4 at a radial interval.

[0008] Reference numeral 7 denotes a straight guide tube, the front end of which is the second guide tube.
A roller 22 which is held by a pressing plate 20 at the front end of the male helicoid ring 5 and is provided at its rear end as a guide means engages with the guide groove 2a of the second fixed cylinder 2 from the inner diameter side and moves in the optical axis direction. You can go straight. 8 is a female helicoid ring,
The female helicoid portion 8a formed on the inner peripheral surface is helicoidally connected to the second male helicoid ring 5 on the inner diameter side of the first male helicoid ring 4. Reference numeral 9 denotes a front lens barrel, which is fixed to the inner diameter of the front end portion of the female helicoid ring 8, and a roller 23 serving as a guide means provided at the rear end thereof is provided in the guide tube 7 with a guide groove in the optical axis direction. The guide tube 7 is engaged with the guide tube 7 from the inner diameter side and held so as to be able to move straight on the guide tube 7. The front-group lens barrel 9 has a third-group lens barrel 1 that holds a second-group lens barrel 10 at its inner diameter.
An electric aperture device 14 is held at the front of the first and second lens barrels 10.

Reference numeral 12 denotes a rear group lens barrel, which is integrally attached to a rear end opening of the first fixed barrel 1. Reference numeral 13 denotes an auxiliary ring, which is arranged between the operation ring 6 and the first fixed cylinder 1 and is interlocked with the movement of the operation ring 6 in the straight traveling direction. Reference numeral 15 denotes an electric circuit mounted, which is mounted on the inner peripheral portion of the second fixed cylinder 2 through an opening 2c by a mounting holding plate 16, and the mounting holding plate 16 is engaged at its distal end by an engaging portion 16a. The rear end fixing portion 16b is screwed to the mounting holding plate mounting portion 2b at the rear end of the second fixed cylinder 2. Reference numeral 17 denotes a flexible printed wiring board, which is attached along the outer peripheral surfaces of the straight guide tube 7 and the front lens barrel 9 to connect the electric circuit mounting 15 and the electric aperture device 14.

The camera lens optical system of the present embodiment is a magnifying optical system. However, in the magnifying optical system, an exposure multiple is usually applied depending on a photographing magnification. I call it a number. Also,
In the photographic lens system of the present embodiment, the electric aperture device 14 is driven by communication control with the camera side.
At this time, it is necessary to provide the data of the effective F-number to the camera according to the position of the lens optical system, that is, the photographing magnification. In the present embodiment, the current position of the lens optical system is detected by a position detecting device (not shown), and an effective F-number corresponding to the photographing magnification is given to the camera. Further, the electric circuit mounting 15 performs a process of driving the electric diaphragm device 14 by a control signal from the camera side.

First, an assembling procedure of the embodiment having the above-described configuration will be described. First, the second group lens barrel 10 and the third group lens barrel 11 are fixed to the front group lens barrel 9, and the rollers 23 are engaged with the guide grooves 7 a of the linear guide tube 7. Next, the guide groove 2 of the second fixed cylinder 2 to which the mounting holding plate 16 for holding the electric circuit mounting 15 is attached.
The roller 22 of the straight guide cylinder 7 is engaged with a. In this state, the first fixed cylinder 1 was further attached, and then the operating ring 6, the first male helicoid ring 4 and the second male helicoid ring 5 were partially assembled on the female helicoid part 1a of the first fixed cylinder 1. Helicoid-binding things. At this stage, the linear guide cylinder 7 is held by the presser plate 20 so as to be rotatable with respect to the second male helicoid ring 5. Next, the female helicoid ring 8 is
The male helicoid ring 5 is assembled while being helicoid-bonded, and fixed to the front lens barrel 9 at a predetermined position. Finally, the rear lens barrel 12 and the mount 3 are attached to complete the lens barrel.

Next, the operation of the lens barrel of this embodiment will be described. When the operating ring 6 is rotated, the male helicoid part 4a of the first male helicoid ring 4 and the female helicoid part 1a of the first fixed cylinder 1 are helicoid-coupled to each other. 6 itself moves in the optical axis direction while rotating. Further, the linear guide tube 7 rotatably held with respect to the second male helicoid ring 5 cannot rotate since the roller 22 is engaged with the guide groove 2a of the second fixed cylinder 2, and cannot move in the linear direction. Move only to. Further, the male helicoid portion 5a of the second male helicoid ring 5 has a female helicoid portion 8
Although a is helicoid-coupled, the roller 23 of the front lens barrel 9 that is integrally fixed is engaged with the guide groove 7a of the rectilinear guide cylinder 7, and thus rotates with respect to the rectilinear guide cylinder 7. As a result, the female helicoid ring 8 moves straight.

In this embodiment, the female helicoid portion 1a of the first fixed cylinder 1 and the male helicoid portion 4a of the first male helicoid ring 4, the male helicoid portion 5a of the second male helicoid ring 5 and the female helicoid ring 8 Each of the helicoid portions 8a is formed as a helicoidal connection. However, by making the engagement with a cam and a roller, the amount of feeding can be made non-linear,
For example, when it is desired to improve the resolution of position detection at a certain position, it is possible to perform an operation such as increasing the movement amount of the straight guide tube relative to the movement amount of the front lens barrel. In the present embodiment, the rollers 22, 23, which are the means for engaging with the guide grooves 2a, 7a, are provided as separate parts. Cost reduction can be expected. In this embodiment, the lens optical system has been described as the magnifying optical system. However, the object of the present invention can be achieved even when the zoom optical system is used to provide focal length data to the camera. In this embodiment, the lens barrel is an interchangeable lens barrel, but it goes without saying that the lens barrel may be a lens barrel fixed to the camera body.

[0014]

As described above, according to the first aspect of the present invention, there is provided a first fixed cylinder, a second fixed cylinder integrally disposed on an inner periphery of the first fixed cylinder, and a first fixed cylinder. A lens barrel comprising a rotating barrel engaged with a fixed barrel and rotated out, and a front lens barrel engaged with the first fixed barrel and the rotating barrel and fed straight forward; And a first guide means rotatably held in the second fixed barrel and movably engaged with a first guide groove provided in the second fixed barrel in the optical axis direction. A guide tube having a second guide groove which engages with the second guide means and which movably engages the front lens barrel in the optical axis direction; mounting of an electric circuit; And the electric circuit mounting and holding means held by the second fixed cylinder between the front group lens barrel and the second fixed cylinder that extend straight. It makes it possible to place efficiently electrical circuit mounted. According to the present invention as set forth in claim 2, the electric circuit mounting and holding means has an engaging portion with the second fixing cylinder at the front end and a fixing portion at the rear end, thereby reducing parts such as screws. Electric circuit packaging can be maintained at a low cost. According to a third aspect of the present invention, there is provided the connector for connection with another printed wiring board on the electric circuit mounting, wherein the second fixed cylinder has an opening at a position where the electric circuit mounting is located. This facilitates the work of connection and inspection of the electric circuit mounting function, and also allows the height of electric circuit components on the electric circuit to be absorbed to save space and reduce the size.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a lens barrel according to an embodiment of the present invention when the lens barrel is shortened.

FIG. 2 is a vertical cross-sectional view of the same when it is extended.

FIG. 3 is an exploded perspective view of the main part.

[Explanation of symbols]

1. first fixed cylinder, 1a .. female helicoid part, 2. second fixed cylinder, 2a .. guide groove, 2b .. mounting holding plate mounting part, 2c .. opening, 3 ... mount, 4. ..The first male helicoid ring, 4a..the male helicoid part, 5..the second male helicoid ring, 5a..the male helicoid part, 6, .. the operating ring,
7 ··· Straight guide tube, 7a ··· guide groove, 8 ··· female helicoid ring, 8a ··· female helicoid part, 9 · · · front group barrel 10 ·
・ 2nd group lens barrel, 11 ・ ・ 3rd group lens barrel, 12 ・ ・ Rear group lens barrel, 1
3 ··· Auxiliary ring, 14 ··· Electrical drawing device, 15 ··· Electrical circuit mounting, 16 ··· Mounting holding plate, 16a ··· Engaging part, 1
6b ··· Rear end fixing portion, 17 ··· Flexible printed wiring board, 20 ··· Holding plate, 22, 23 ··· roller.

Claims (3)

[Claims] A first fixed cylinder, a second fixed cylinder integrally disposed on an inner periphery of the first fixed cylinder, a rotary cylinder engaged with the first fixed cylinder and rotated and fed out; A lens barrel composed of the first fixed barrel and a front lens barrel that is linearly extended and engaged with the rotary barrel, the lens barrel being rotatably held by the rotary barrel and provided on the second fixed barrel. First guide means movably engaged in the optical axis direction with the first guide groove provided, and further engages with the second guide means provided on the front lens barrel to move the front lens barrel. A guide tube having a second guide groove movably engaged in the optical axis direction, an electric circuit mounting, and an electric circuit mounting holding held between the second fixed tube and the guide tube by the second fixed tube And a lens barrel having an electric circuit mounting. 2. The electric circuit mounting device according to claim 1, wherein the electric circuit mounting holding means has an engaging portion with the second fixing cylinder at a front end portion and a fixing portion at a rear end portion. Lens barrel. 3. The lens barrel according to claim 1, wherein the second fixed cylinder has an opening at a position where the electric circuit is mounted.