JP2002023035A - Accessory attaching structure for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide accessory attaching structure for easily attaching an accessory and a photographing lens for a camera with simple constitution without using special space. SOLUTION: This accessory attaching structure for attachably/detachably attaching the accessory (for example, a lens converter 30) having male screw parts 41 and 42 and a male screw part 43 not seen in this figure on the outer periphery to the leading end of the photographing lens barrel 10 of a camera main body 1 is provided with a lens barrel side attaching part having female screw parts 11, 12 and 13 where a female screw is formed in the peripheral direction and notched parts 21, 22 and 23 where the female screw is not formed in an optical axis direction in a partial area in the peripheral direction at the leading end of the lens barrel 10. Meanwhile, it is provided with an accessory side attaching part where the male screw capable of being screwed with the female screw is formed only at a position corresponding to the partial area in the peripheral direction at the trailing end of the accessory, and the accessory is easily attached to the lens barrel 10 by mutual connection of both attaching parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for an accessory mounted on a front surface of a taking lens barrel.

[0002]

2. Description of the Related Art Some of the techniques relating to a structure for mounting accessories to a camera have long been provided with a screw for mounting various standardized optical filters formed around the entire front end of a taking lens barrel. Although it is known, it is necessary to rotate accessories several times when attaching and detaching. Many attempts have been made to further improve the operability at the time of attachment / detachment in order to eliminate this troublesomeness.

For example, in a bayonet-type mounting device taught in Japanese Patent Publication No. 54-8098, an accessory (lens hood) is attached to a bayonet claw of the same type corresponding to a plurality of bayonet claws provided in a lens barrel of a camera. The lens hood is also provided on itself, so that the lens hood is detachable.

Further, as a structure for easily attaching accessories, an attachment structure as taught in Japanese Patent Application Laid-Open No. 11-352545 has been proposed. this is,
The spring-biased holder makes it possible to securely hold existing optical filters, etc., which are presupposed to be screwed together, with a spring-biased holder. This is a method that can be easily performed without turning around.

[0005]

However, the bayonet-type mounting device disclosed in Japanese Patent Publication No. 54-8098 is a special space (space) having protrusions for providing bayonet claws at both ends of the lens barrel and accessories. ) Is required, so that the accessories themselves become longer in the optical axis direction, and when attached, there is a problem that the entire camera becomes longer.

In the mounting structure disclosed in Japanese Patent Application Laid-Open No. H11-352545, a mechanism for a movable part is required. Further, extra members such as an operation ring, a plurality of springs, and a holding body are required, resulting in an increase in the number of parts and an increase in cost. In addition, since the outer shape of the lens barrel tip becomes large, it does not contribute to downsizing. Furthermore, since this is mechanically complicated, there is a high possibility of failure.

[0007] Even if the conventional technology as described above makes it detachable by an easy operation, the mechanism itself for realizing the detachment cannot be made simple, and the complexity and the cost increase. However, a specific technology that balances these has not yet been shown.

Accordingly, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a mounting structure for a camera accessory which can be easily mounted with a simple configuration without using a special space. It is in.

[0009]

Means for Solving the Problems In order to solve the above problems and achieve the object, the present invention takes the following measures. For example, according to the first aspect of the present invention, in an accessory mounting structure in which an accessory having an external thread on the outer periphery (that is, an accessory in a narrow sense) is detachably attached to a distal end portion of a lens barrel, the accessory mounting structure is formed in a circumferential direction of the distal end portion of the lens barrel. Provided on the lens barrel side (female screw side) mounting part having a female screw formed, and a notch part in which the female screw is not formed along the optical axis direction with respect to a partial area in the circumferential direction, and the accessory. And an accessory side (male screw side) mounting part on which the male screw is formed which can be screwed to the female screw only at a position corresponding to the partial area in the circumferential direction. A mounting structure is proposed. The female screw and the male screw are the accessory mounting structure according to the first aspect of the present invention, wherein the female screw and the male screw are formed in a plurality of regions at predetermined intervals in a circumferential direction.

[0010] According to the second aspect of the present invention, an accessory having a male screw on the outer periphery is detachably attached to the female screw formed at the tip of the lens barrel by screwing the male screw. In the accessory mounting structure, when attaching the accessory to the lens barrel, the male screw is not screwed together with the female screw in the optical axis direction in a state where the male screw is aligned with a predetermined position in the circumferential direction. And the female screw can be inserted to a position where they overlap by a predetermined amount or more in the optical axis direction, and after this insertion, the male screw and the female screw are relatively rotated, so that the male screw and the female screw are screwed together. We propose an accessory mounting structure for the constructed camera.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The gist of the present invention will be described below in detail with reference to FIGS. 1A and 1B show an embodiment of a photographing lens of a camera according to the present invention. FIG. 1A is a plan view showing the photographing lens and a photographing lens barrel provided with the photographing lens, and FIG.

A photographic lens 5 whose front surface is exposed and whose outer periphery is circular
A substantially annular pressing frame 6 for pressing the peripheral portion of the front spherical surface of the photographing lens 5 from the front, and an opening protruding inward so that the peripheral portion of the rear spherical surface of the photographing lens 5 abuts and is positioned. Between the abutting wall and the taking lens barrel 10
Is fixed inside.

The photographing lens barrel 10 is formed in an annular cylindrical body, and various accessories (for example, a lens converter described later, or a lens hood, a filter, a cap, etc.) are provided on an extension of the optical axis O of the fixed photographing lens 5. ) Are formed at mounting portions separated at a predetermined interval so that they can be mounted.

More specifically, a first female screw portion 11, a second female screw portion 12, and a second female screw portion 12 having the same length and having female screws of a predetermined pitch are formed on the inner peripheral surface of the front edge portion of the barrel of the taking lens barrel 10. The three female threads 13 are arranged at equal intervals (120 ° intervals), and the first notch 21, the second notch 22, and the third notch are provided between the three female threads 13 without thread. Notch 23
Are formed at equal intervals (120 ° intervals) with the same width W.

Preferably, a photographing lens side index 9 serving as a mark of an accessory mounting position is engraved or protruded near the end of the photographing lens barrel outer peripheral wall in which the second cutout portion 22 is formed. (See FIG. 3).

The first to third notches 21, 22, 23
Is formed simultaneously with the formation of the female screw of the taking lens barrel 10 by a mold as is well known. Or as another method,
After the thread of the female screw is formed continuously over the entire circumference, the thread may be cut off at a predetermined position and in a predetermined range.

As described above, the accessory mounting structure of the present invention is an example of an accessory (accessory) for the above-described photographing lens barrel 10 provided on the camera body 1 side, as shown in FIG. ) And (b) can be mounted.

The lens converter as an accessory of the present embodiment has a longitudinal sectional structure shown in FIG.
FIG. 2B shows a planar structure of the lens converter viewed from a side where a male screw portion described later is formed. The lens converter 30 attached to the above-described photographic lens barrel 10 has first to third external thread portions 41, 42, and 43 at a plurality of locations on the outer periphery, and is detachable from the distal end portion of the photographic lens barrel 10. It has a simple structure.

That is, the lens converter 30 has a conversion lens 35 whose front surface is exposed and whose outer periphery is circular. The conversion lens 35 projects from the inside of the converter lens barrel 40 so that the substantially annular holding frame 36 for pressing the peripheral portion of the lens from the front and the peripheral portion of the rear spherical surface of the conversion lens 35 are in contact with each other and positioned. The lens barrel 40 is fixed inside the converter barrel 40 by the provided lens contact wall.

A first male screw part 41 and a second male screw part 42 of the same length are formed on the outer peripheral surface of the rear end part of the cylindrical body of the converter barrel 40 with male screws having the same predetermined pitch as the female screw described above. And third male screw portions 43 are respectively protruded at equal intervals (120 ° intervals), and the gaps between these are outer peripheral surfaces each having a predetermined diameter without a thread.

Preferably, the lens converter 30
Also on accessories such as, an accessory-side index 39 serving as a mark of a mounting position at the time of mounting is engraved or protruded on, for example, the outer peripheral surface of the rear end portion of the cylindrical body near the first male screw portion 41. (See FIG. 3).

The above-mentioned photographing lens index 9 and the accessory index 39 are preferably provided at positions that are easy to see as alignment marks when a desired accessory is attached to the tip of the photographing lens barrel 10.

These first to third male screw portions 41, 42, 4
3 is screwed into the first to third female screw portions 11, 12, and 13, the end face 45 of the converter barrel 40 in FIG. 2 advances in the direction of the arrow, and the end face of the photographing lens barrel 10 in FIG. The pitch and the like of each screw are set so as to be completed at a position where the screw comes into contact with No. 15. Further, the relative rotation angle (rotation angle) to be turned until the completion is less than 120 °, and preferably within 90 ° is convenient.

Note that such a mounting structure can be similarly applied to, for example, a lens hood, a filter, a cap, and the like, in addition to the illustrated lens converter 30.

Next, the interconnection between the above-described photographic lens barrel 10 and the lens converter 30 as an accessory will be described. FIG. 3 shows that the lens converter 30 is attached to the taking lens barrel 10 of the camera.

The accessory mounting structure of the present invention has a first
A structure for detachably attaching an accessory (lens converter 30) having the third male screw portions 41, 42, 43 to the distal end of the taking lens barrel 10 in the camera body 1,
It is provided for both the wearer and the wearer.

That is, the photographing lens barrel 1 to be mounted.
The first to third female screw portions 11, 12, and 13 each having a female screw formed in the circumferential direction at the leading end of the zero, and the female screw along the optical axis direction with respect to a part of the circumferential region. First not formed
A lens barrel side mounting portion (female screw side) having third notches 21, 22, and 23 is provided, while the rear end of the lens converter 30 to be mounted has the above-mentioned circumferential direction. Only at a position corresponding to the partial area, an accessory-side attachment site (male screw side) in which a male screw that can be screwed to the female screw is formed is provided. Then, these two attachment parts are screwed together by a predetermined rotation operation, so that the lens converter 30 can be easily attached in front of the taking lens barrel 10.

Therefore, when attaching desired accessories to the photographing lens barrel 10 of the camera, first, the photographing lens side index 9 and the accessory 9 provided near the upper end of each upper surface, which are markers of the positional relationship to be attached, are attached. The product side index 39 is set as shown in the figure.

Next, in a state where the male screw is aligned with a predetermined position (index position) in the circumferential direction, the end face 45 of the converter barrel 40 is not screwed with the female screw but along the optical axis direction. Until the female screw substantially contacts the end face 15 of the taking lens barrel 10 and the female screw and the male screw overlap by a predetermined amount or more in the optical axis direction.

After the insertion, by rotating the converter barrel 40 of the lens converter with respect to the photographing lens barrel 10 by a predetermined angle or more, the female screw and the female screw are screwed together, and the lens converter 30 is securely attached.

FIG. 4 shows a state in which the lens converter 30 is mounted by the relative rotation operation as described above. The male and female screws are screwed together at the end face 45 of the converter barrel 40.
2 (see FIG. 2) is completed in a predetermined direction until it firmly contacts the end face 15 (see FIG. 1) of the taking lens barrel 10.

In this embodiment, the rotation angle in the predetermined direction is set to approximately 15 °. Therefore, for example, at a position where the accessory side index 39 is closest to the shooting lens side index 9, the lens converter 3 is attached to the shooting lens barrel 10 side.
When one accessory such as 0 is pressed along the direction of the optical axis, the first to third external thread portions 41, 42, 43 of the accessory are attached to the first to third notch portions 21 of the taking lens barrel 10. , 22, and 23 respectively.

When the accessory is rotated in a predetermined direction from this state, the first to third female screw portions 11 and 11 of the photographing lens barrel 10 are rotated.
The first to third male screw portions 41, 42, 4 of accessories are provided on 12, 13.
3 are engaged with each other and are firmly connected only by turning them by about 15 °, so that they can be used for photographing. Also, when removing the accessory from this state, it is possible to replace the accessory with another desired accessory by a simple operation similarly by performing the above-described mounting operation procedure in reverse.

As described above, according to the camera accessory mounting structure of one embodiment of the present invention, it is not necessary to rotate the accessory several times as in the related art, and only by rotating about 15 ° is required. Quick and easy removal. In addition, since this connection method is based on the assumption that the connection method can be directly applied to a screw-type accessory, it is structurally very simple and does not require any new space for the engagement portion.

Of course, according to this accessory mounting structure, even a "screw-in" type accessory having a connecting external thread formed over the entire circumference of the existing photographing lens barrel 10 can be mounted. To respond. Similarly,
The converter barrel 40 in which the male screw of the present embodiment is formed on the circumference and several places can be attached to the photographing lens barrel 10 and the like in which the female screw portion for connection is formed over the entire existing circumference. Can respond.

The photographing lens barrel 10 having such an accessory mounting structure includes an existing screw type lens converter which has been widely sold conventionally, and an existing screw type lens converter which is frequently used in exchange for photographing. The various correction filters and the like can be used as they are as accessories to the camera by a conventional mounting operation. That is, the accessory mounting structure has bidirectional compatibility between the photographing lens barrel 10 and the accessory.

(Modification) The above embodiment may be modified as follows. The illustrated first to third notches 21,
22 and 23 are equally provided with three same widths W,
It is not limited to this depending on the type and use of the accessory. For example, when the mounting direction (up-down direction or the like) affecting the photographing result is predetermined (for example, a special lens hood, a special effect filter, or the like), the first to third notches 21, 22, and 23 are provided. Instead of arranging them at equal intervals, they may be modified so that they can be interconnected only at predetermined positions, for example, by forming them only one wide.

Alternatively, a predetermined index may be separately provided, and may be attached only by fitting at that position.

Further, the pair of related indices 9 and 39 may be used as a mark of the mounting start position or a mark of the mounting completed position, and the present invention is not limited to this. It can be devised.

The number of the male screw, the female screw and the notch is not limited to three, but may be two or four or more.

Further, the embodiment may be modified as follows, and the same effect as that of the above-described embodiment can be expected. For example, it is also possible to use a screw which is already continuously engraved on the entire circumference and cut out only a predetermined portion thereof with a predetermined tool. In the case of a conventional filter or a photographing lens barrel in which a female screw is formed, a predetermined cutout portion may be formed only by cutting off the corresponding thread portion, and the same result as described above can be obtained.
In addition, various modifications can be made without departing from the spirit of the present invention.

Although the embodiments have been described above, the present invention includes the following inventions. For example, (1) in the accessory attachment structure for attaching accessories to the cylindrical portion at the tip of the lens barrel, the lens barrel has cutouts having no screw portion at at least two places around the circumference. Female screw part, and a male screw part formed at the rear end of the accessory and capable of screwing with the female screw of the lens barrel, wherein the male screw part is formed of the female screw part. An accessory attachment structure characterized by being provided only at the circumferential position corresponding to the notch can be provided.

(2) Accessories having external threads on the outer periphery
In the accessory mounting structure in which the above male screw is screwed into the female screw formed at the tip of the lens barrel to be detachably attached,
The accessory can provide an accessory mounting structure, characterized in that the accessory has a cutout in which the male screw is not formed along the optical axis direction with respect to a part of the circumferential direction where the female screw is formed.

(3) An accessory having a male screw on the outer periphery
In the accessory mounting structure in which the male screw is screwed into the female screw formed at the tip of the lens barrel to be detachably attached,
The accessory mounting structure can be provided, wherein the lens barrel has a cutout portion in which the female screw is not formed along a part of the female screw in a circumferential direction along the optical axis direction.

(4) An accessory having a male screw on the outer periphery
In the accessory mounting structure in which the male screw is screwed into the female screw formed at the distal end of the lens barrel to be detachably attached, the lens barrel is arranged in the optical axis direction with respect to a part of the circumferential direction of the female screw. Has a notch where the female screw is not formed along,
The accessory has a male screw portion in which the male screw is formed in a circumferential range corresponding to a partial region in a circumferential direction of the notch portion,
When attaching the accessory to the lens barrel, the male screw portion is inserted along the optical axis direction in a state in which the male screw portion is aligned with the notch portion in the circumferential direction, and then the male screw portion is relatively rotated. An accessory attachment structure characterized in that the screw and the female screw are screwed together.

(5) In the above (1) or (4),
The plurality of male screw portions and the plurality of female screw portions are arranged at intervals in the circumferential direction. (6) In the above (2), a plurality of the male screw portions are arranged at intervals in a circumferential direction. (7) In the above (3), a plurality of the female screw portions are arranged at intervals in a circumferential direction.

(8) Accessories having an external thread on the outer periphery
In the accessory mounting structure in which the male screw is screwed into the female screw formed integrally with the distal end portion of the lens barrel to be detachably attached, the lens barrel is configured such that a part of the female screw in a circumferential direction is partially illuminated. It is possible to provide an accessory mounting structure having a cutout portion in which the female screw is not formed along the axial direction.

(9) Only in the space for the filter screw,
The lens converter can be easily attached, and a standardized filter can be attached to the lens barrel. Conversely, the lens converter can be attached to a lens barrel with only conventional filter screws. Can provide structure.

[0049]

As described above, according to the present invention, a special space is provided.
It is possible to provide an accessory mounting structure that can easily mount camera accessories such as a lens converter with a simple configuration without using (space).

[Brief description of the drawings]

FIGS. 1A and 1B show a photographing lens of a camera according to the present invention, and FIG. 1A is a plan view of a photographing lens barrel provided with the photographing lens, and FIG. Is a longitudinal sectional view thereof.

FIGS. 2A and 2B show a lens converter as an accessory to be attached to a taking lens barrel.
(A) is a longitudinal sectional view of this lens converter, FIG.
(B) is the top view.

FIG. 3 is a perspective view showing attachment of an accessory to a taking lens barrel of the camera according to the present invention.

FIG. 4 is a perspective view showing a state in which accessories are attached to a taking lens barrel of the camera according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Camera body, 5 ... Photography lens, 6 ... Holding frame (for fixing photography lens), 9 ... Photography lens side index, 10 ... Photography lens barrel, 11 ... 1st internal thread part (lens tube side attachment part), Reference numeral 12: second female screw portion (mounting portion on the lens barrel side), 13: third female screw portion (mounting portion on the lens barrel side), 15: end face (end face of the photographing lens barrel side), 21: first notch portion, Reference numeral 22: second cutout portion, 23: third cutout portion, 30: lens converter (accessory), 35: conversion lens, 36: holding frame (for fixing the conversion lens), 39: accessory side index, 40 ... Converter barrel, 41: first male screw part (accessory side mounting part), 42: second male screw part (accessory side mounting part), 43: third male screw part (accessory side mounting part), 45 … End face (accessory side end face).

Claims (3)

[Claims] 1. An accessory mounting structure for detachably mounting an accessory having an external thread on an outer periphery to a distal end of a lens barrel, comprising: a female screw formed in a circumferential direction of a distal end of the lens barrel; A lens barrel side mounting portion having a notch portion in which the female screw is not formed along the optical axis direction with respect to a portion of the region, and only at a position provided on the accessory and corresponding to the portion of the circumferential direction. And an accessory-side attachment portion formed with a male screw that can be screwed to the female screw. 2. The camera according to claim 1, wherein the female screw and the male screw are formed in a plurality of areas at predetermined intervals in a circumferential direction. Construction. 3. An accessory mounting structure for removably mounting an accessory having an external thread on an outer periphery thereof by screwing the external thread onto a female screw formed at a distal end of the lens barrel, wherein the accessory is attached to the lens barrel. When mounting the product, the male screw and the female screw are separated by a predetermined amount in the optical axis direction along the optical axis direction without screwing together with the female screw with the male screw aligned with a predetermined position in the circumferential direction. The camera is characterized in that the male screw and the female screw are screwed into each other by allowing the male screw and the female screw to rotate relative to each other after the insertion, and the male screw and the female screw are relatively rotated after the insertion. Accessory mounting structure.