JP2009300926A - Camera accessory and camera system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera accessory equipped with a dust-proof and drip-proof mechanism which does not require extensive work for structure of an accessory-side mount and a camera-side mount, prevents aligning accuracy of an optical axis and workability from being lowered, and has a simple constitution for facilitating replacement of elastic members. <P>SOLUTION: A teleconverter is equipped with: a lens barrel 110, internally possessing an optical system for transmitting subject light; a converter-side mount 120; provided in the lens barrel 110 and engaged with the camera-side mount 210; and a holding member 320 for holding an annular elastic member and attached detachably to the lens barrel 110. The annular elastic member is formed in shape, having a tip part 313 tightly abutting against a camera outside appearance part, around the camera-side mount 210 substantially in the optical axis direction and having a substantially circular cross section, and a cylindrical part 312 which extends substantially in the optical axis direction and is elastically deformed to be curved to the outside, in a direction which is perpendicular to the optical axis, when the teleconverter is coupled to a camera body 200. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a camera accessory, and more particularly to a dustproof and drip-proof mechanism for a camera accessory that couples a camera accessory and a camera body in a watertight state.

  In an interchangeable lens camera in which a lens barrel can be detachably attached, the camera body and the lens barrel are connected and integrated by a mount mechanism provided between the camera body and the lens barrel. ing. There are various types of mounting mechanisms, and bayonet type mounting mechanisms are common in current interchangeable lens cameras, for example, single-lens reflex cameras.

  The bayonet mount mechanism with a general configuration does not take into account any dust and splash proofing between the lens barrel and the camera body, and the camera may malfunction when used in rainy or dusty environments. There is. For example, when used in the rain, rainwater may enter from the gap between the lens barrel and the camera body, causing mold on the camera and lens components, and possibly causing electronic components to malfunction. For example, when used at a construction site where there is a lot of dust, dust enters from the gap between the lens barrel and the camera body and adheres to the surface of the lens or image sensor, reducing the shooting performance. There is a possibility that the movement of the drive unit may be hindered by entering the drive unit such as the cam groove of the lens barrel or the mirror box of the camera body.

  In order to reduce this possibility, various types of mount mechanisms having dustproof and dripproof performance have been proposed.

  For example, the invention disclosed in Patent Document 1 is a camera accessory configured by attaching an accessory-side mount member that engages with a camera-side mount provided on the camera body to the accessory body. An elastic member that is sandwiched between and held between the accessory side mount member and the camera side mount and that closely contacts a portion of the camera body that surrounds the outer periphery of the camera side mount is provided. The close contact portion is formed in a conical shape that spreads toward the tip.

  In the invention disclosed in Patent Document 2, the waterproof ring in the interchangeable lens barrel is housed and fixed inside an annular cavity region surrounded by the inner peripheral portion of the rear cover member and the outer peripheral portion of the lens mount member. An annular portion, a coated annular portion connected to the fixed annular portion and covering a peripheral portion of the outer surface of the lens mount member, and connected to the coated annular portion and extending along the optical axis direction of the interchangeable lens barrel main body. The mounting member includes a contact annular portion that can contact the mount surface with a predetermined pressure.

Japanese Patent No. 3728080 (Japanese Patent Laid-Open No. 11-174562) JP 2005-17393 A

  The accessory-side mount and the camera-side mount are important members responsible for precise optical axis alignment in a single-lens reflex camera system capable of exchanging lenses, and require high manufacturing accuracy and assembly accuracy as well as strength. In other words, it is necessary to match the central axis of an optical system provided in a camera accessory such as an interchangeable lens barrel and a conversion lens as much as possible with the central axis of a solid-state imaging device in the camera body. It greatly affects the shooting performance. Both of the above prior arts employ a structure in which the elastic member is sandwiched between the accessory side mount and the lens barrel.

  In Patent Document 1, the accessory side mount is attached after the elastic member is housed in the groove for preventing the elastic member from being detached provided on the inner periphery of the lens outer ring. At this time, if the elastic member is not securely stored in the retaining groove, the elastic member is sandwiched between the mount and the lens outer ring, and the mount is inclined. As a result, the optical axis shifts and the image falls, and there is a possibility that the photographing performance will deteriorate.

  In Patent Document 2, in order to prevent the elastic member from coming off, it is necessary to process the mount instead of the rear cover member in order to accommodate the fixed annular portion. A high accuracy is required for the processing of the mount, and the strength of the mount may be reduced by the processing.

  In addition, since the elastic member used for waterproofing generally deteriorates over time, it becomes necessary to replace the elastic member held between the accessory-side mounts when used for a long time. At this time, in the above-mentioned conventional technology, the mount must be removed, and a general user who is unfamiliar with disassembling the lens, etc., touches the mount part to cause a deviation between the lens and the optical axis of the camera. There is a risk of performance degradation.

  The present invention has been made in view of such a situation. A dustproof and drip-proof mechanism having a simple configuration that does not require large processing to the structure of the accessory side mount and the camera side mount and that allows easy replacement of the elastic member. An object of the present invention is to provide a camera accessory.

  In addition, the mount members of interchangeable lens SLR cameras that are currently distributed vary in the amount of protrusion from the camera exterior member depending on the manufacturer and model. For example, there are cameras that project nearly 2 mm, and almost the same as the exterior member. Some cameras are in the same plane. Among them, an object of the present invention is to provide a camera accessory equipped with a dustproof and splashproof mechanism suitable for a single-lens reflex camera having a structure in which the mounting surface of the camera side mounting member is substantially flush with the camera appearance member. .

In order to achieve the above object, the present invention provides:
An accessory body containing an optical system that transmits subject light;
Provided on the accessory body, an accessory side mounting member that engages with a camera side mounting member provided on the camera body,
A holding member that holds an annular elastic member and is detachable from the accessory body;
With
The annular elastic member includes a distal end portion having a substantially circular cross section that comes into close contact with the camera external portion around the camera-side mount member in a substantially optical axis direction, extends in a substantially optical axis direction, and the accessory body and the camera body And a cylindrical portion that is elastically deformed so as to be bent outward in the direction perpendicular to the optical axis when coupled to each other.

  Furthermore, in the present invention, the present invention is configured such that the tip end part is in close contact with an accessory side contacted part having a tapered surface.

  Furthermore, the present invention is such that, in the above invention, the tip portion protrudes in a direction substantially parallel to the tapered surface with respect to the cylindrical portion.

  Furthermore, in the above invention, the present invention is configured such that the accessory side contacted portion is at least one of an outer peripheral surface of the accessory main body rear end and an outer peripheral surface of the accessory side mount member.

  According to the dustproof and drip-proof mechanism of the camera accessory embodying the present invention, the structure of the accessory-side mount and the camera-side mount can be obtained by adopting a structure in which the elastic member is held by the holding member in the appearance portion instead of the mount portion of the camera accessory. A dust-proof and drip-proof mechanism suitable for single-lens reflex cameras with a structure where the mounting surface of the accessory-side mount is approximately flush with the camera exterior member, with no need for large processing, and easy replacement of the elastic member Camera accessories can be provided.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment.

  FIG. 1 is an exploded perspective view showing an appearance of a camera system having a teleconverter according to an embodiment of the present invention and a camera body to which the teleconverter is mounted. FIG. 2 is a cross-sectional view of main components of the dustproof / splashproof mechanism provided in the teleconverter shown in FIG. FIG. 3 is an enlarged view around the mechanism when the teleconverter shown in FIG. 1 is mounted on the camera body. FIG. 4 is an enlarged view around the mechanism when a teleconverter according to another embodiment of the present invention is mounted on the camera body.

  A teleconverter 100 shown in the perspective development view of FIG. 1 includes a lens barrel 110 and a converter-side mount 120. The lens barrel 110 has an optical system having a characteristic of shifting the original focal length of an interchangeable lens (not shown) coupled to the subject side of the teleconverter 100 to the telephoto side. The converter side mount 120 is a bayonet type mount, and is fixed to the rear end surface of the lens barrel 110 by a plurality of converter side mount fixing screws 130.

  An annular elastic member 310 having a predetermined shape, which will be described later, for providing a dustproof and drip-proof function and a holding member 320 for holding the annular elastic member 310 in a predetermined place are provided on the rear outer peripheral surface of the lens barrel 110. It is attached. The holding member 320 is provided with a plurality of screw holes through which the holding member fixing screws 321 for fixing to the lens barrel 110 are passed. The holding member 320 is attached to the lens barrel 110 and fixed with the holding member fixing screws 321. As a result, the annular elastic member 310 is held between the inner peripheral surface of the holding member 320 and the outer peripheral surface of the lens barrel 110.

  The camera body 200 is a typical interchangeable lens single-lens reflex camera for mounting the teleconverter 100 embodying the present invention, and a bayonet-type camera side mount 210 for coupling with a camera accessory such as an interchangeable lens or a converter. I have. The camera side mount 210 is fixed to a part of a main frame (not shown) in the camera body 200 by a plurality of camera side mount fixing screws (not shown). The camera-side mount 210 is arranged such that the mount surface is on the same plane as the external appearance part on the front surface of the camera body 200.

  The camera body 200 and the teleconverter 100 are coupled in the following manner. That is, by engaging the bayonet claws of the converter-side mount 120 with the camera-side mount 210, the bayonet claws on the converter side and the bayonet claws on the camera side are engaged with each other, so that the bayonet claws are engaged with each other. Thus, the teleconverter 100 can be coupled. At this time, the back side of the bayonet claw of the converter side mount 120 is pushed by the strong resistance of a leaf spring (not shown) provided on the back side of each bayonet claw of the camera side mount 210, and the converter side mount surface is placed on the camera side mount surface. It will be in the state of pressure contact.

  The exterior of the camera body 200 includes a release button 220, a mode setting dial 230 for setting a shooting mode, a jog dial for setting a continuous shooting mode, scene selection, and the like (not shown). Is provided. A signal corresponding to the operation on the operation unit is input to the CPU in the main board, and the operation of the camera is controlled.

  The following photographing operations are common for interchangeable lens single-lens reflex cameras. That is, by pressing the release button 220 of the camera body 200, the subject light captured from the photographing optical system of the lens barrel is incident on the solid-state image sensor arranged on the optical axis. The incident subject light is photoelectrically converted into a signal charge corresponding to the amount of charge in a solid-state imaging device such as a CCD or CMOS, and then converted into a voltage and output. The output voltage output from the solid-state imaging device is subjected to predetermined signal processing and image processing by a signal / image processing unit such as an A / D converter, a white balance correction circuit, and a gamma correction circuit. The processed image data is recorded on a recording medium (not shown) such as an SD card (registered trademark).

  As shown in the component cross-sectional view of FIG. 2, by fitting the flange portion 311 provided on the front end portion of the annular elastic member 310 over the entire circumference into the notch portion 322 provided on the inner peripheral surface of the holding member 320, The annular elastic member 310 is held by the holding member 320. In addition, a tapered portion 111 with an inclination is provided on the outer peripheral surface of the rear end portion of the lens barrel 110. In addition to the flange portion 311 described above, the annular elastic member 310 has a cylindrical portion 312 extending in the optical axis direction and a tip portion 313 that contacts the camera body 200, and has a cross section similar to an L shape as a whole. ing. The tip portion 313 is arranged so as to extend closer to the camera imaging surface (not shown) than the mount surface on the converter side in a state where the annular elastic member 310 is arranged at a predetermined position of the converter side mount 120.

  The tip portion 313 is formed with a projecting portion having a circular cross section in a direction parallel to the inclination direction of the taper portion 111 provided on the inscribed lens barrel 110, such as a truncated cone constricted toward the tip. It has a shape. As will be described later, the annular elastic member 310 can be brought into close contact with a camera external portion around the camera-side mount 210 to exhibit a dustproof and drip-proof effect at the coupling portion. The dust-proof and drip-proof mechanism is mounted on the teleconverter 100 by inserting the holding member 320 to which the annular elastic member 310 is attached from behind the lens barrel 110 and fixing with the plurality of holding member fixing screws 321.

  FIG. 3 is an enlarged cross-sectional view of the periphery of the annular elastic member 310 in a state where the teleconverter 100 according to the embodiment of the present invention is coupled to the camera body 200. When the teleconverter 100 is to be attached to the camera body 200, the tip 313 having a circular cross section extending closer to the camera imaging surface than the mount surface on the converter side is in the optical axis direction on the camera external portion around the camera side mount 210. To touch. When the teleconverter 100 is further pushed in, the annular elastic member 310 that is in contact with the camera external appearance part is elastically deformed. As described above, since the annular elastic member 310 is shaped like a truncated cone, when the distal end portion 313 is pushed toward the subject side in the optical axis direction by the camera external appearance portion, the cylindrical portion 312 moves outward in the optical axis vertical direction. While curving, the inner peripheral surface of the tip portion 313 contacts the outer peripheral surface of the rear end portion of the lens barrel 110.

  Since the above-described tapered portion 111 is provided at the rear end portion of the lens barrel 110, when the inner peripheral surface of the tip portion 313 contacts the tapered portion 111, the tip portion 313 is perpendicular to the optical axis along the inclination of the taper portion 111. Pushed outward in the direction. As a result, the curve toward the outside of the cylindrical portion 312 is supplementarily guided to prevent the tip portion 313 from being sandwiched between the mount surface on the converter side and the mount surface on the camera side, thereby avoiding poor mounting of the teleconverter 100. Is done. In this state, the front end portion 313 of the annular elastic member 310 is in close contact with the outer appearance portion of the camera body 200 and the taper portion 111 at the rear end of the lens barrel 110, so that water droplets and dust are inside the camera body 200 and the teleconverter 100. It works to prevent entering. Finally, by rotating either the teleconverter 100 or the camera body 200 in a predetermined direction, both bayonet claws are engaged with each other, and the teleconverter 100 and the camera body 200 are coupled in a watertight state.

  In the above-described embodiment, the tapered portion 111 is provided on the outer peripheral surface of the rear end portion of the lens barrel 110. However, the following case may be considered as another embodiment of the present invention. That is, instead of providing the tapered portion 111 in the lens barrel 110, a tapered portion is provided on the outer peripheral surface of the converter-side mount 120 exposed to the outside in the optical axis vertical direction as shown in FIG. As a result, the tip 313 of the annular elastic member 310 can be brought into contact with the camera exterior and the converter-side mount 120, and the same effect as in the above-described embodiment can be obtained.

  Further, in the above-described embodiment, the dust-proof and drip-proof mechanism is applied to the teleconverter as an example of the camera accessory. However, the same effect as that of the present embodiment can be obtained even when applied to the interchangeable lens barrel as another example of the accessory. It is clear. Even if the present invention is applied to a wide converter instead of a teleconverter, the same effect can be obtained. Furthermore, by applying a dust-proof and drip-proof mechanism to the interchangeable lens barrel and coupling this interchangeable lens to a teleconverter, it is also possible to exhibit a dustproof and drip-proof effect between the interchangeable lens and the teleconverter.

  According to the camera accessory embodying the present invention, the elastic member is structured to be held by the holding member not in the mount part of the camera accessory but by the holding member, so that a large processing to the structure of the accessory side mount and the camera side mount is unnecessary. In addition, a camera accessory equipped with a dustproof and drip-proof mechanism suitable for a single-lens reflex camera having a structure in which the mounting surface of the camera-side mount is substantially flush with the camera exterior member with a simple configuration that allows easy replacement of the elastic member. Can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing an external appearance of a teleconverter that is an embodiment of the present invention and a camera body to which the teleconverter is mounted. It is sectional drawing of the main components of the dustproof drip-proof mechanism with which the teleconverter shown in FIG. 1 was equipped. It is an enlarged view of the mechanism periphery when the teleconverter shown in FIG. 1 is mounted on the camera body. It is an enlarged view of the mechanism periphery when the teleconverter which is other embodiment of this invention is mounted | worn with a camera main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Teleconverter 110 Lens barrel 111 Tapered part 120 Converter side mount 200 Camera body 210 Camera side mount 310 Annular elastic member 311 Flange part 312 Cylindrical part 313 Tip part 320 Holding member

Claims (5)

An accessory body containing an optical system that transmits subject light;
Provided on the accessory body, an accessory side mounting member that engages with a camera side mounting member provided on the camera body,
A holding member that holds an annular elastic member and is detachable from the accessory body;
With
The annular elastic member includes a tip end portion having a substantially circular cross section that is in close contact with the camera external portion around the camera side mount member in a substantially optical axis direction, and extends in a substantially optical axis direction, and the accessory body and the camera body And a cylindrical portion that is elastically deformed so as to bend outward in the direction perpendicular to the optical axis when coupled to each other. The camera accessory according to claim 1, wherein the distal end portion is further in close contact with an accessory-side contact portion having a tapered surface. 3. The camera accessory according to claim 1, wherein the tip portion protrudes in a direction substantially parallel to the tapered surface with respect to the cylindrical portion. 4. The accessory side contacted portion is at least one of an outer peripheral surface of the accessory main body rear end portion and an outer peripheral surface of the accessory side mount member. The listed camera accessories. A camera body in which the mounting surface of the camera-side mount member that engages with the accessory-side mount member is substantially flush with the camera exterior portion;
The camera accessory according to any one of claims 1 to 4,
Having a camera system.

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