JP2770071B2 - Lens barrel for optical equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for a lens barrel for optical equipment.

2. Description of the Related Art Single-lens reflex cameras and the like vary in mount shape and franchise back depending on the camera manufacturer. Therefore, it is very difficult to use interchangeable lenses. However, CCTV cameras have adopted the C-mount when the screen size is 1 "(inch) and 2/3" (inch). Also used the planned value of fb = 17.5mm, so it could be used with lenses from any manufacturer.

However, with the development of image receiving elements used for CCTV cameras, for example, even in the case of CCD elements, the screen size has changed from 1 "to 2".
The ratio has shifted to / 3 "and further to 1/2", and in the future it has also shifted to 1/3 ", and CCIV cameras have also rapidly started to be downsized. Especially in the 1" and 2/3 "eras As mentioned above, the franco-back of the camera was also a C-mount standard value, but when the camera moved to 1/2 "inch, the franco-back with a C-mount screw commonly called a CS mount was fb = 12.5mm. Has been commercialized, and since this project was in line with the conditions of lens miniaturization and cost reduction, any camera manufacturer
The current situation is that CS mount cameras are being rapidly commercialized. Therefore, as an interchangeable lens maker, a C-mount lens is attached to a CS-mount camera, and a mount adapter with a thickness of the difference between franc and back dimensions is created for use. At present, it is necessary to commercialize as a CS mount lens and to deal with it.

Problems to be Solved by the Invention However, since a lens barrel designed as a CS mount lens cannot be a lens for a C mount camera due to the relationship between franc and back, it may also be used for a C mount camera depending on the user's request. At present, it is necessary to design and commercialize the product, and the number of models increases, and the product management department and the manufacturing department are forced to adopt a very troublesome production system.

Means for Solving the Problems Accordingly, the present invention has been made in view of the above-described problems, and has a fixed body fixed to the optical device main body and a movable body provided along the optical axis with respect to the fixed body. Moving body, and an operating ring interposed between the fixed body and the moving body to move the moving body with respect to the fixed body, and the moving ring holding the optical system by rotating the operating ring. In the lens barrel for an optical device having a function of moving a body along an optical axis and obtaining a moving amount of a mount surface for attaching to a camera having a different Franc-Back and correcting a difference between the Franc-Back, the operation ring Is divided into a first operation ring and a second operation ring. The first operation ring is provided rotatably on the fixed body side, and the second operation ring is provided rotatably on the moving body side having a lens barrel holding an optical system. By rotating one of the first operation ring and the second operation ring, By moving the moving body including the operation ring along the optical axis to correct the difference between the franc and the back, by rotating the other operation ring,
The lens barrel holding the optical system is moved along the optical axis so as to be focused, and the C-mount is rotated by either the first operation ring or the second operation ring. The amount of movement of the mounting surface that compensates for the difference between the franc back of the camera and the franc back of the CS mount camera is secured, and the amount of extension for focusing is secured by rotating the other operation ring. C-mount camera and CS
It is an object of the present invention to provide a device for a lens barrel that also serves as a mount camera.

Embodiments The present invention will be described in detail below based on one embodiment of a lens barrel for a CCTV camera according to the present invention shown in the drawings.

In the embodiment shown in FIGS. 1 and 2, the lens barrel according to the present invention is fixed to the fixed barrel (1) on the fixed body side mounted on the camera body, and to the fixed barrel (1). The mounting ring (2) on the fixed body side, the connecting ring (3) on the moving body side supported by the fixed lens barrel (1) so as to be able to move straight along the optical axis direction, and the mounting ring (2) are rotatably provided. The first operating ring (4), the second operating ring (5) rotatably provided on the connecting ring (3), and the mirror supported by the connecting ring (3) so as to be able to move straight along the optical axis direction. It consists of a torso (6) and the like.

The fixed lens barrel (1) on the fixed body side has a mounting screw (1a) to be attached to the optical device main body, and a flange-like portion (1b) thereof.
Are integrally attached so that one side surface of the optical device body is in close contact with the optical device body. The mounting ring (2) is rotatably fitted to the outer cylindrical portion on the other side of the flange-like portion (1b) of the fixed lens barrel (1), and the mounting position of the mounting ring (2) can be determined at any position. So that the friction spring (14) can be attached to the mounting ring (2).
And the flange-like portion (1b), and the other side is pressed by a fixing ring (15), and the friction spring (14)
The fixed lens barrel (1) and the mounting ring (2) are configured to be integrated at an arbitrary mounting position by the frictional resistance described above.

The small cylinder part of the connection ring (3) is fitted to the inner cylinder side of the fixed barrel (1) so as to be movable in the optical axis direction, and the connection ring (3) on the movable body side is movable in the optical axis direction. I support it. In the case of the embodiment, the inner rear end portion of the mounting ring (2) and the inner wall of the connecting ring (3), which are in an integrated relationship after the positioning of the mount and the mount, are opposed to the key by the key. The connection is performed in a keyway relationship, and the connection ring (3) moves linearly along the optical axis direction with respect to the fixed lens barrel (1) described above.

The connecting ring (3) is provided on the inner cylinder side of the mounting ring (2).
A first operating ring (4) having an operating portion (4c) outside the large cylindrical portion is rotatably fitted with a fitting cylindrical portion, and an inner flange-like portion (4b) of the fitting cylindrical portion is formed. The mounting ring (2) on the fixed body side and the disc-like wall surface (3b) connecting the small and large cylindrical parts of the connecting ring (3) on the moving body side are provided so as to be sandwiched. The inner flange-like portion (4b) and the disc-like wall surface (3b) of the connecting ring (3) preferably have two or more contact points on opposing mutual surfaces, and one contact point is provided. An operation surface such as a cam surface or an inclined surface having a lead angle that increases and decreases in the optical axis direction with respect to a predetermined rotation angle is provided on the surface side, and the other end surface side includes a conical projection or the like abutting on the operation surface. A contact portion is provided.

Further, an elastic member (11) having an elastic force in the optical axis direction is accommodated between the fixed lens barrel (1) and the connecting ring (3), and the elastic member (11) is fixed to the fixed lens barrel ( The holding ring (10) is screwed and fixed to the connecting ring (3) while being held between the connecting ring (3) and the connecting ring (3) and the fixed lens barrel (1) by the repulsive force of the elastic member (11). The elastic member (11) is configured to be pressurized in a direction in which the gap is always narrowed, and the elastic force of the elastic member (11) causes the upper portion (4b) of the inner flange of the first operation ring (4) to be pressed.
The operating surface of the disk-shaped wall portion (3b) of the connecting ring (3) and the contacting portion are configured to be always in close contact with each other, and the elasticity is obtained by rotating the first operating ring (4). It is configured to overcome the repulsive force of the member (11) and obtain a thrust in a direction to increase the distance between the connecting ring (3) and the fixed lens barrel (1).

In addition, the operating surface having a lead angle and the contact portion that comes into contact with the operating surface are preferably two or more, as described above. In this case, it is not necessary that the operating surfaces be completely equidistant. You can set the interval just enough. Further, the fixed lens barrel (1) and the first operation ring (4) are configured to be in direct contact with each other on a plane intersecting the optical axis, and the contact surface has an operation surface having the above-described lead angle directly. The same effect can be obtained as a mechanism in which the abutting portion that abuts on the operation surface is preferably abutted at two or more places. It is also possible to use an operation surface having an angle so that a double movement amount can be secured, and the configuration of the contact point according to the present invention is not limited to the configuration of the above-described embodiment.

On the other hand, a straight guide groove (3a) is provided in the large cylindrical portion of the connection ring (3) linearly along the optical axis direction, and a second operation ring (5) is rotatably provided on the outer periphery thereof. is there. A lead groove (5a) is spirally provided in the overlapped cylindrical portion of the second operating ring (5) overlapping the straight guide groove (3a). The second
The lead groove (5a) of the operation ring (5) has, for example, a lead angle such that the lead ring advances and retreats by 5 mm while rotating by 90 °. A lens barrel (6) is provided on the inner cylinder part of the connecting ring (3) so as to be able to move straight along the optical axis direction, and a straight guide screw (12) implanted in the lens barrel (6) is provided. , Through a guide roller (13) provided on the outer periphery thereof, the straight guide groove (3) of the connection ring (3).
a) and the lead groove (5a) of the second operation ring (5) are fitted simultaneously. Further, the outer periphery of the overlapped cylindrical portion of the second operation ring (5) is covered by the operation portion (4c) of the first operation ring (4), and the operation portion of the second operation ring (5) is provided in front of the operation portion (4c). It is exposed in a protruding form.

Further, a front lens frame (8) and a rear lens frame (9) for holding the front lens group (20) and the rear lens group (30) are screwed into the inner cylinder of the lens barrel (6). An aperture scale ring (7) for operating aperture blades is rotatably provided on the outer cylinder of the lens barrel (6).

The iris scale ring (7) moves linearly and integrally with the connecting ring (3) in the optical axis direction together with the lens barrel (6), and does not move with respect to the connecting ring (3) in the optical axis direction. Ring (5)
As shown in FIG. 1, the display cylinder portion (5b) is provided so as to be exposed when the C mount is set, and to be exposed when the CS mount is set, as shown in FIG.

In the embodiment having the above configuration, FIG.
To compensate for the difference of 5mm between the flange back of the mount camera and the flange back of the CS mount camera, the second
When a correction movement amount of 5 mm is provided in the lead groove (5a) of the operation ring (5) and the second operation ring (5) is rotated, the straight guide screw (12) of the lens barrel (6) in FIG. With the rotation of the lead groove (5a) from the flange-back state of the C-mount drawn toward the disk-shaped wall portion (3b) side of the connection ring (3), the linear guide screw (12) is moved by the operation ring (3). 2), the lens barrel (6) holding the optical system in which the straight guide screw (12) is implanted moves straight along the optical axis, and is guided by the straight guide groove (3a) shown in FIG. This changes to the arrangement of the optical system that secures the Franc / Back dimensions of the CS mount camera. In this state, when the lens barrel is mounted on the CS mount camera and the first operation ring (4) is rotated for focusing, the operation surfaces of the connection ring (3) and the first operation ring (4) are obtained. The distance between the connecting ring (3) and the first operating ring (4) is widened by overcoming the repulsive force of the elastic member (11) by the thrust of the contact portion and the thrust of the elastic member (11), and is held by the lens barrel (6) on the moving body side. The moving optical system moves, and the focusing corresponding to the shooting distance is performed. Further, even when the first operation ring is rotated in the reverse direction, the contact surface of the connection ring (3) and the operation surface of the first operation ring (4) are always in close contact by the repulsive force of the elastic member (11). In this state, the optical system held by the lens barrel (6) moves in the retracting direction, and in this case also, the focusing operation is performed.

In the above-mentioned apparatus, the second operation ring (5) is used to obtain the amount of movement of the mount surface for correcting the difference between the franc and the back.
By rotating, it is possible to provide a display of a munt name to be applied, a photographing magnification at the time of close-up photographing, a photographing distance display, and the like on the exposed outer portion of the display tube portion (5b).

In another embodiment shown in FIGS. 3 and 4, a configuration in which the usage of the first operation ring and the second operation ring shown in FIG. This embodiment shows a configuration in which a rotation operation is performed to correct a difference between a franc and a back dimension, and a rotation operation of a second operation ring is performed to perform focusing. In FIG. 1, the thrust for focusing was obtained from the thrust of the operating surface having a lead angle, the thrust of the contact portion, and the repulsion of the elastic member. In the embodiment, the thrust of a normal helicoid screw is used, and although there are some differences, the configuration of the present invention can be realized by using any of the thrusts.

The lens barrel of the present invention in FIGS. 3 and 4 includes a fixed lens barrel (1) on the fixed body side mounted on the camera body, and a mounting ring (2) on the fixed body side fixed to the fixed lens barrel (1). A connecting ring (3), a first operating ring (4), and a second operating ring on the moving body side, which are supported so as to be able to move straight along the optical axis direction with respect to the mounting ring (2).
An operation ring (5), a lens barrel (6) holding an optical system, a front lens group frame (8) provided to hold a front lens group (20) and a rear lens group (30), and a rear lens group frame ( 9), a straight guide screw (12), a guide roller (13), a straight guide key (16), and the like.

The fixed lens barrel (1) has a mount screw (1a) to be mounted on the optical device main body, and is integrally attached to the optical device main body.
A mounting ring (2) is rotatably fitted to the inner barrel side of the fixed barrel (1), and is mounted to the fixed barrel (1) with set screws (1c) so that the mount can be positioned at any position. Ring (2)
Are configured to be integrally fixed.

An aperture ring (7) is rotatably fitted to the outer ring side of the mounting ring (2), and a first operation ring (4) is rotatably mounted to the inner cylinder side.

The connecting ring (3) on the moving body side is attached to the mounting ring (2) in the first direction.
A linear guide groove (2a) for linearly moving along the optical axis by rotating the operation ring (4), and the lens barrel (6) is moved straight along the optical axis by rotating the second operation ring (5). A straight guide keyway (2b) that fits into the straight guide key (16) is provided.

The first operation ring (4) has a lead groove (4a) for correcting the difference between the flange back of the C-mount camera and the flange back of the CS mount camera, while the connection ring (3) is fitted on the inner cylinder side. We support each other.

The connecting ring (3) has a linear guide that fits simultaneously with the linear guide groove (2a) of the mounting ring (2) and the lead groove (4a) of the first operating ring (4) via the guide roller (13). While the screw (12) is implanted, the second operation ring (5) is rotatably screwed with a small screw in a direction opposite to a helicoid screw described later.

As described above, the second operation ring (5) is rotatably screwed to the connection ring (3) with a small screw, has a helicoid screw (5c) in the inner cylinder portion, and has a lens barrel (5). It is screwed to the helicoid screw (6c) provided on the outer cylinder part of 6).

The lens barrel (6) has a front group lens frame (8) and a rear group lens frame (9) holding an optical system, which are fixed with screws and integrally provided. Further, by a rotation operation of the second operation ring (5), a linear guide key (16) for linearly moving the lens barrel (6) along the optical axis is fixed with a screw, and the linear guide key (16) on the fixed body side is fixed. The key ring (2b) of the mounting ring (2) is engaged with the key ring (2b) so that the key ring and the key groove are connected.

In the above apparatus, the first operation ring (4) is used to obtain the amount of movement of the mount surface for correcting the difference between the franc and the back.
By rotating, a display of a mount name to be applied, a photographing magnification at the time of close-up photographing, a photographing distance display, and the like can be provided on the outer appearance of the display tube portion (4d) that is exposed.

In the lens barrel having the structure shown in FIGS. 3 and 4, when the first operation ring (4) is rotated, the straight guide screw (12) is attached with the guide roller (13) fitted. The connection ring (3) is attached because it is planted in the connection ring (3) in a state where it passes through the straight guide groove (2a) of the ring (2) and the lead groove (4a) of the first operation ring (4). Move straight along the straight guide groove (2a) of the ring (2), and follow the lead groove (4a) for correcting the difference (5 mm) between the franc-back dimension of the C-mount camera and the franc-back dimension of the CS-mount camera. As shown in the figure, the optical system is arranged in such a way that the ヂ -back dimensions of the CS mount umera are secured. In this state, when the second operation ring (5) is rotated, the lens barrel (6) can be focused by a general helicoid screw type focusing mechanism.

The display cylinders (5d) of the first and second operation rings exposed by the rotation operation of the second operation ring (5) in FIG. 1 and the first operation ring (4) in FIG. ), (4d) By displaying the appropriate mount display on the external surface (like CS, for example), the state of the setting of the operation ring can be seen at a glance, and also close-up photography The function of the lens barrel can be enhanced by displaying necessary information at the time, a scale of photographing magnification, and the like.

Effects As described above, according to the lens barrel for an optical device according to the present invention, a fixed body fixed to the optical device body, and a movable body movably provided along the optical axis with respect to the fixed body, An operating ring interposed between the fixed body and the moving body to move the moving body with respect to the fixed body, and the moving body holding the optical system is moved to the optical axis by rotating the operating ring. Move along,
In a lens barrel for an optical device having a function of obtaining a movement amount of a mount surface for correcting a difference in Franc-Back by attaching to a camera having a different Franc-Back, the operation ring is a first operation ring and a second operation ring. The first operation ring is provided rotatably on the fixed body side, the second operation ring is provided rotatably on the moving body side having a lens barrel holding the optical system, and the first operation ring or the second operation ring is provided. One of the rotating operations moves the moving body including the other operating ring along the optical axis to correct the difference between the franc and the back, and the rotating operation of the other operating ring causes the mirror holding the optical system. Since the torso portion is configured to move along the optical axis to focus, a mounting surface that corrects the difference between franc and back by rotating one of the first operating ring and the second operating ring. So that the amount of movement of The square of the operation ring rotation operation, by the way obtain the amount of movement for focusing, can be used also serves to cameras having different Furandjibakku.

In other words, it can be used as a lens mount for C-mount cameras and CS-mount cameras without using an adapter, etc.
In addition, since it is a lens barrel that can ensure perfect compatibility, it is possible to deal with users without increasing the number of models, and conversely, it is possible to increase the production volume collectively In addition to the effects that can be solved in the production process of dispersing and producing in a variety of models and the troubles of parts management, the effect of increasing the production effect can be expected.

When viewed as a product, in the case of a lens barrel for a CCTV camera, the focal length is relatively short, and therefore the amount of extension of the lens barrel is not small, so C-mount for medium telephoto lenses, standard lenses, wide-angle lenses, etc. When a lens mirror copper adopting the mechanism of the present invention is used as a lens barrel for a camera, if this franc-back correction movement amount is used as a movement amount for focusing the lens, a close-up ring with a helicoid can be obtained. It becomes like a built-in lens barrel, and the amount of extension of the macro shooting range can be obtained, and the image magnification target etc. required for close-up shooting is displayed on the external surface of the operation member exposed when the operation member is rotated and extended By doing so, it is possible to set the amount of advance with priority to magnification, and to set shooting conditions such that fine adjustment for focusing is performed by rotating another operating ring for focusing. As Has the effect of improving the function.

Transformation into a lens barrel for macro photography, such as a lens barrel with a built-in close-up ring with a helicoid, leads to the fact that several types of adapters etc. necessary for taking enlarged pictures such as a close-up ring have been eliminated, and the lens barrel This also has the effect of increasing the added value of the product.

In the case where the size of the camera is further reduced in the future and the franc-back becomes even shorter, if the common use of the adapter is viewed, there will be restrictions due to the shape of the C-mount screw. = A shortening condition with no intermediate shortening value of 12.5 mm shorter than 1.5 mm or shorter than 5 mm. In the former case, the adapter is used as a washer, and in the latter case, an adapter having a male screw and a female screw is used. In the case of shortening of 5 mm or more, there are few restrictions on the lens barrel side due to restrictions such as the built-in filter used on the camera side, so the shortening condition of 1.5 mm or less practically remains only. . However, according to the configuration of the present invention, it is possible to efficiently set dimensions on the camera side and the lens barrel side, and there is also an effect of increasing the degree of freedom in design.

As described above, an object of the present invention is to provide a lens barrel device for use with other types of lens barrels for CCTV cameras.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of an embodiment of a lens barrel for a CCTV camera to which the present invention is applied, showing a state having a franc-back dimension for a C-mount camera, and FIG.
FIG. 3 is a similar cross-sectional view showing a state in which the lens barrel of FIG. 1 is switched to a franc-back dimension for a CS mount camera. FIG. FIG. 4 shows the state of the franc-back dimensions for the C-mount camera as in FIG. 1, and FIG. 4 is a similar cross-sectional view showing the state in which the lens barrel of FIG. It is. In Fig. 1 and Fig. 2, 1 ... fixed lens barrel, 1a ... mounting screw 2 ... mounting ring 3 ... connecting ring, 3a ... straight guide groove 4 ... first operating ring 5 ... 2 operation ring, 5a ... lead groove 5b ... display cylinder part 6 ... lens barrel 7 ... aperture scale ring 8 ... front group lens frame, 20 ... front group lens 9 ... rear group lens frame, 30 ... ... Rear group lens 10... Pressing ring 11... Elastic member 12... Straight guide screw 13... Guide roller 14. Friction spring 15... Fixing ring 1 In FIG. 3 and FIG. Body, 1a Mounting screw 2 Mounting ring 2a Straight guide groove 2b Straight guide keyway 3 Connection ring 4 First operation ring 4a Lead groove 4b Display cylinder 5 second operation ring 6 lens barrel 7 aperture scale ring 8 front group lens frame 20 front group lens 9 rear group lens frame 30 rear group lens 12 straight forward Guidance screw 13 …… The inner roller 16 ...... linear guide key

Claims (3)

(57) [Claims] 1. A fixed body fixed to an optical device main body, a movable body movably provided along the optical axis with respect to the fixed body,
An operating ring interposed between the fixed body and the moving body to move the moving body with respect to the fixed body, and the moving body holding the optical system is moved to the optical axis by rotating the operating ring. The operation ring is attached to a camera having a different franc-back and has a function of obtaining the amount of movement of a mount surface for correcting the difference in the franc-back. And a second operation ring. The first operation ring is rotatably provided on the fixed body side, and the second operation ring is rotatably provided on the moving body side having a lens barrel holding the optical system.
By rotating one of the operation ring and the second operation ring, the moving body including the other operation ring is moved along the optical axis to correct the difference between the franc and the back, and the rotation operation of the other operation ring is performed. A lens barrel for an optical apparatus, wherein a lens barrel holding an optical system is moved along an optical axis to focus. 2. The lens barrel for an optical device according to claim 1, wherein the operating ring is a first operating ring and a second operating ring.
The first operating ring is rotatably provided on the fixed body side, and the second operating ring is rotatably provided on the moving body side having the lens barrel holding the optical system. The moving body including the second operation ring is moved along the optical axis by the operation to correct the franc-back difference, and the lens barrel holding the optical system is moved to the optical axis by the rotation operation of the second operation ring. A lens barrel for an optical device, wherein the lens barrel moves along and focuses. 3. An operating ring for obtaining an amount of movement of a mount surface for correcting a difference between a franc and a back in the lens barrel for an optical device according to claim 1 or 2. A lens barrel for an optical device, characterized in that a display of a mount name to be applied or a photographing magnification and a photographing distance at the time of close-up photographing is provided for an exposed appearance.