JPS6057330A - Switching mechanism of variable magnification finder - Google Patents

Abstract

PURPOSE:To simplify an operation mechanism and to improve the efficiency of working and assembling and also to reduce the space by constituting a mechanism so that a holding frame having one optical element is moved directly by a holding frame having the other optical element. CONSTITUTION:When a photographic lens system is set to a long focus lens, a long focus optical element 6 is placed in the optical path and a short focus optical element 7 is removed from the optical path in a finder optical system. When the photographic lens system is set to a short focus lens in this state, a gear 19 is rotated in accordance with this setting, and therefore, a frame body 15 is turned in the vertical direction to place a short focus lens 16 in the optical path. Simultaneously, the tip of the frame body 15 is brought into contact with the lower end of a frame body 8 of the long focus optical element 6 to push up the frame body 8, and a long focus lens is removed from the optical path. When the photographic lens system is set to the long focus lens again, the short focus lens 16 is removed from the optical path, and the long focus lens 9 is placed in the optical path. In such constitution, the space is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to several structures in which two optical elements in a finder optical system attached to a camera are alternately switched in and out of the optical path.

As for the internal structure of this 81, it is JP-A-55-9093.
No. 7 is known, and this camera has an engaging claw on each of the standard finder lens and the telephoto finder lens, and is provided with an elongated lens actuating slide that engages with both engaging claws. By moving the slide in the longitudinal direction, when one finder lens is inserted into the optical path, the other Q finder lens is retracted, or vice versa to alternately switch between the two types of 7 finder lenses. However, with this finder switching mechanism, the drive transmission of the switching stop is to the lens actuating slide, and both optical elements are actuated separately, so the structure becomes complicated, and it is difficult to use within the limited camera body. The disadvantage was that it required a large amount of space.

The present invention improves this well-known - The purpose of this invention is to simplify the fiJJ mechanism, improve the efficiency of processing and assembling beans, and to obtain a switching mechanism that greatly reduces space and is especially applicable to small cameras. .

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. The 7-inder chamber (1) of the camera body has a front chamber (1) and a rear chamber (3), and the rear chamber (3) has an eyepiece lens (4) at the rear end and an Arvada lens (5) at the front end. ) are fixed respectively. The front chamber (2) has a long focus optical element (6) at the rear and a short focus optical element (6) at the front.
7). The long focus optical element (6) has a long focus lens (9) fixed in a frame (8) made of synthetic resin, and has shaft holes (10) (10) bored on both sides of the upper end. This is the shaft bearing hole (
121 (1) is rotatably attached to the pin (13), and a coiled spring (121) is wound around the outer periphery of one shaft bearing hole (1), and one end of the spring is connected to the projecting piece (11) of the frame (8). ),
The other end is the front! (2) The long focal length optical element (6) is latched to the earth wall surface and biased so that it is located within the U pupil optical path.

The short focus optical element (7) fixes the short focus lens 06) in a frame (15) also made of synthetic porcelain, and has a shaft (1η) protruding from both sides of the lower end, which is connected to the front chamber (2). The long focus optical element (6) is rotatably attached to the shaft bearing hole (18) (18) formed in the front and rear sides 14I of the frame body (15), and the long focus optical element (6) are arranged so that the tips of frame # (8) are in close contact with each other.On the other hand, at the outer end of the O axis (17) is a short/long focus switching device (not shown) for the photographing lens system.
Attach the gear (19) that interlocks with the

Note that QO) indicates a cover glass.

Since the invention is constructed as described above, when the photographic lens system is centered on a long focal length lens, the finder optical system linked thereto also has a long focal length optical element (6) that is attached to a coiled spring ( The frame body (8) is held in a vertical state with the pin (13) as a fulcrum by the force of 1→, and the long focal length lens fixed thereto is placed in the optical path.On the other hand, the short focal length optical element (7) ) The Fi axis (frame body 05 with 1η as a fulcrum) is rotated and held in a water SF state, and the short focal length lens α6) fixed thereto is retracted out of the optical path. When the photographic lens system υ lens is set to the short focal length lens from this state, the gear (19) rotates in conjunction with the operation of the switching device, so the frame body (15) moves vertically with the 1 kilometer (17) as the fulcrum. The short focal length lens (16) fixed thereto is positioned within the optical path. At the same time, the tip of the frame (15) is attached to the lower end of the long focal length optical element (6) held vertically and the Q frame (8), and the frame (8) is rolled up. The front chamber (2) is pushed upward against the tension of the α-shaft, rotates the frame (8) to the water position (S) using the pin (13) as a fulcrum, and opens the front chamber (2).
The frame body (15) is positioned on the upper surface and prevents the frame body (8) from moving downward, and the pure focus lens (9) is retracted out of the optical path (see Fig. 1 and line 11ti). Also - photographic lens type Q lens? I- When the long focus lens is set again, the short focus optical element (7) is rotated by the gear (1@) and the frame body (15) is transferred to the water droplet shape 4 to become the short focus lens 06. is retracted out of the optical path, and the long focal length optical element (6) is retracted from the frame (1
5) Since the v support is divided by h, the frame body (8) is shifted to the vertical state by the tension of the coiled spring (1 x), and the long focal length lens (
9) can be located in the optical path.

It should be noted that the long/short focus optical element (6
) (7) The long focal length lens (9), the frame 1 (8), the short focal length lens (16), and the frame body α5)' (i-a) may be integrally formed with a modified fat material.

As described in detail above, the present invention allows the frame of one optical element Q to directly operate the frame of the other optical element, so the configuration is extremely simplified and the efficiency of processing work can be improved. Not only can it be easily assembled into the narrow viewfinder chamber of a small camera, but it can also be operated smoothly and reliably because it has a mechanism that switches by the tension of a coiled spring. Moreover, it has excellent effects such as being able to provide at low cost a uniform product that stably operates over a long period of time without failure due to its simple structure.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional side view of the present invention, and Fig. 2 is a horizontal 1! i
'P-plane view, showing a state in which the short-focus optical detector is positioned within the optical path.

Claims (1)

[Claims] A variable magnification finder that performs magnification by alternately moving the 2aI optical elements that form part of the finder optical system in and out of the optical path is a holder frame that has one optical element and a holder that has the other optical element. A variable magnification 7-inder ■Switching structure characterized in that the frame is engaged with the frame, and movement of one optical element causes the other optical element to be moved.