JPH0116086Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a bayonet mount for an interchangeable lens camera in which a mount spring is interposed between a camera side mount and a lens side mount.

As shown in FIG. 3, the conventional bayonet mount has a plurality of bayonet claws 12c arranged on the back side of the camera-side mount to provide a camera-side abutting surface 12b with an interchangeable lens. This bayonet claw 12c
An annular stepped portion 12d is provided on the outer side of the annular step portion 12d.
A part of the bayonet pawl 12c is provided with a recess 12e cut slightly deeper than the annular step 12d by milling, and the mount spring 13 is mounted so that its elastic portion 13a faces the recess 12e. It is attached to the annular step portion 12d. When the interchangeable lens is attached to the camera body and the lens-side abutting surface (not shown) and the camera-side abutting surface 12b abut, the elastic portion 13 of the mount spring 13
While being pressed against the lens side abutting surface, the lens side is elastically urged against this, and the interchangeable lens is thus held against the camera body. The recess 12e is
Even if the elastic portion 13a of the mount spring 13 is pressed against the lens-side abutting surface and tilts toward the recess 12e, the depth is designed to allow this.

However, such a configuration has the following problems. That is, if the concave portion is machined by milling, the milling itself is expensive, and therefore the overall machining cost becomes relatively high. Furthermore, since high precision is required for machining each recess, a lot of time is required for machining. In short, with the above configuration, it is extremely difficult to reduce processing costs and labor. The present invention was made to solve such problems with the conventional technology, and does not involve processing the mount spring mounting surface by milling.
The abutting surface with the lens side mount on the back of the camera side mount and the mount spring accommodating part are simultaneously formed into an annular shape using a lathe, etc., which saves processing time and cost and facilitates processing. The purpose is to provide a bayonet mount that can be used.

The details of the present invention will be explained below based on the drawings. 1st
The figure shows a main sectional view of one embodiment of the present invention, and FIG. 2 shows a plan view of the same embodiment as viewed from the direction of the arrow in FIG. 1. The camera side mount 2 fixed to the camera body 1 has a lens 4 on the front.
It has a mounting reference surface 2a, and a bayonet claw 2c.
An arcuate abutment surface 2b is provided on the back surface of the abutment surface 2b.
An annular stepped portion 2d for accommodating the mount spring 3 and the elastic portion 3a is provided on the outside of the abutment surface 2.
b and the annular step portion 2d are both machined simultaneously using a lathe. The accommodating portion (annular stepped portion) 2d accommodates a mount spring elastic portion 3a, and the mount spring 3 is attached thereto. In Figure 2, one mount spring is attached to each bayonet claw of the camera side mount, but there are other types of mount springs, such as those formed in the shape of an integral hollow disk. It may be of any shape. The lens 4 has a bayonet claw 4c formed integrally with an abutting surface 4b that abuts the camera-side abutting surface 2b and presses against the mount spring 3. When the lens 4 is attached to the camera side mount 2 configured as described above,
Due to the elasticity of the mount spring 3 that presses against the lens-side bayonet pawl 4c, the camera-side reference surface 2a and the lens-side reference surface 4a are pressed and held, and positioning in the optical axis direction is performed.

In the bayonet mount of the present invention constructed as described above, the mount spring mounting surface of the camera side mount and the back surface of the camera side mount, which conventionally required separate processing such as milling, are processed simultaneously using a lathe. Therefore, it is possible to reduce the number of processing steps without reducing accuracy, which in turn has the effect of reducing processing time and processing costs.

[Brief explanation of the drawing]

FIG. 1 is a main sectional view of an embodiment of the present invention.
FIG. 2 is a plan view of the same embodiment as seen from the direction of the arrow in FIG. 1, and FIG. 3 is a perspective view of the main part of a bayonet mount according to the prior art seen from the same direction as FIG. 1: Camera body, 2: Camera side mount, 2
a: Camera side mount reference surface, 2b: Abutting surface, 2
c: Camera side bayonet claw, 2d: Annular step,
3: Mount spring, 3a: Mount spring elastic part, 4: Lens, 4a: Lens side reference surface, 4b:
Lens side abutting surface, 4c: Lens side bayonet claw,
4d: Pressure contact part.

Claims (1)

[Claim for Utility Model Registration] The elasticity of the mount spring interposed between the camera-side mount and the lens-side mount allows the attached lens to be pressed against the reference surface in front of the camera-side mount and positioned in the optical axis direction. In bayonet mounts for interchangeable lens cameras in which the abutting surface on the back of the camera-side bayonet claw assists in positioning, the arc-shaped abutting surface provided on the back of the camera-side bayonet claw and this abutting surface a camera-side mount having an annular step portion provided on the outside of the mount spring for accommodating the mount spring; a mount spring having an elastic portion housed in the annular step portion; A bayonet mount for an interchangeable lens camera, comprising a lens side mount configured such that its surface abuts the abutting surface of the camera side mount and its pressure contact portion engages with an elastic portion of a mount spring. .