JPS604169Y2 - Lens changing device for small cameras - Google Patents

Description

[Detailed explanation of the invention] This invention is equipped with two photographic lenses with different focal lengths, such as a telephoto lens and a standard lens, or a telephoto lens and a wide-angle lens, and allows these lenses to be selectively replaced at any time. The present invention relates to a lens changing device for a camera.

Conventionally, cameras in which lenses were exchanged by sliding a lens stand to which multiple photographic lenses were attached linearly or by rotating it in a turret style were developed, for example, in the 1970s.
This is well known as described in Japanese Utility Model Publication No. 23082, Japanese Utility Model Publication No. 48-2374, and the like.

However, in any of the above models, the photographic lens can simply be moved on a flat surface along the front of the camera body, so there is no change in the overall size of the camera, including each photographic lens, making it more compact. I can't hope.

In addition, for a lens stand that has a sliding structure, the sliding structure of the lens stand and the finish of the sliding surface must be sufficiently high precision, while for a lens stand that rotates in a turret type, the rotation of the lens stand must be sufficiently high. In this case, there is an inconvenience in that the lens stand shows variations in the direction of the photographing optical path axis, and providing a structure to prevent this has the disadvantage of high costs, and the structure cannot be simplified from the standpoint of lens back accuracy. These conventional methods are unsuitable from a comprehensive standpoint, especially as a small compact camera.

This idea was developed to reduce the size of the camera body as much as possible in a small camera equipped with two interchangeable photographic lenses as described above. The objective of the present invention is to provide a lens changing device that is small and compact when stored, maintains very good accuracy in terms of lens back accuracy, and has a simple configuration.

To explain the embodiment, in FIGS. 1 and 2,
A long-focus photographic lens 1 for telephoto shooting and a standard photographic lens used for normal photography are mounted upright on a camera body 3 or a base, and the axis is perpendicular to the photographing optical path axis. The base of the lens support member 5 is pivotally attached to the lens support member 4, and the lens support member 5 has two arms formed in the shape of a letter square. It is oriented in the radial direction.

The finder optical system is constructed in an inverted Galilean type consisting of an objective lens 6 and an eyepiece lens 7.
The field image magnification obtained by 7 is set to be equal to the photographed image magnification of the long focus photographing lens 1.

Above (or below) the finder optical system is S゛9.
A lens stand 8 that can be rotated by 0° is provided, and a concave lens 9 constituting an afocal optical system is connected to a convex lens 1 on the lens stand 8.
0 is fixedly installed, and the lens 9 is rotated by the rotation of the lens stand 8.
, 10 can appear and disappear within the finder optical system,
The lenses 9 and 10 are located in the finder optical system.
In the state shown in the figure, the field image magnification obtained by lenses 6, 9, 10 and the 7th group is set to be equal to the image magnification of the standard photographic lens 2.

The lens support member 5 and the lens stand 8 are connected via a connecting rod 11 whose both ends are respectively connected to pins 5d and 8b protruding from them, so that they can rotate in conjunction with each other. When either the operating portion 5c of the member 5 or the operating portion 8a of the lens stand 8 is operated, both the members 5 and 8 rotate in conjunction with each other.

Further, a click roller 13 biased by a spring 12 is brought into elastic contact with the connecting rod 11 to clickly restrict the rotation of the lens stand 8 of the support member 5 for lens exchange. Both the members 5 and 8 can be locked in two setting positions: , telephoto, and standard.

Further, a stopper 14.15 for regulating the rotation angle of the lens support member 5 and a stopper 16.17 for regulating the rotational position of the lens stand 8 are respectively fixedly fixed to the camera body 3 and facing each other. Further, an arc-shaped dustproof cover 18 is provided inside the support part 5a of the long-focus photographing lens 1 that protrudes outside the camera body 3 during telephoto shooting to follow the movement trajectory of the support part 5a to prevent dust from entering the inside of the camera. When the standard photographing lens 2 is set on the photographing optical path, the long focus photographing lens 1 is placed between the end of the cover 18 extending within the contour of the camera body 3 and the front wall of the camera body 3. A pocket portion 19 is provided as shown in the figure.

Further, the distance from the support part 5b to the shaft 4 is set shorter than the distance from the support part 5a to the shaft 4, so that the standard photographic lens 2 can rotate around the shaft 4 further inside the dustproof cover 18. It is located in

FIG. 1 is a diagram showing a state in which telephoto shooting is possible by setting the long focal length photographing lens 1 on the photographing optical path axis in the above configuration. In this state, the lens stand 8 is equipped with an afocal lens. The 9° 10th group is retracted out of the finder optical path.

Therefore, the image magnifications of the photographing system and the finder system are equally balanced, and the click roller 13 is connected to the connecting rod 11.
by elastically pressing the lens support member 5 to the stopper 14.
In addition, the lens stand 8 is pressed against the stopper 16 to maintain a stable state.

At this time, the long focal length photographing lens 1 is at the most forwardly protruding position, and protrudes from the front surface of the camera body 3 as shown in FIG.

Change the shooting lens from long focus shooting lens 1 to standard shooting lens 2.
To change the lens, press the operation part 5c of the lens support member 5.
Alternatively, when the operation part 8a of the lens stand 8 is manually rotated clockwise, the lens support member 5 and the lens stand 8 are rotated clockwise in conjunction with each other via the connecting rod 11, and the long focus photographing lens 1 is rotated clockwise. Pocket part 19 by moving backward while rotating.
It will be contained within.

At the same time, the standard photographing lens 2 rotates behind the dustproof cover 18 and advances onto the photographing optical path.

Then, as shown in FIG. 2, the rotation angles of both members 5 and 8 are regulated by stoppers 15 and 17, respectively, and the members are stopped.

At this time as well, the click roller 13 presses the two parts 5, 8 via the connecting rod 11 against the stopper 15, 17 and stabilizes them.

Therefore, the standard photographing lens 2 is placed on the photographing optical path, and the afocal lenses 9 and 10 of the lens stand 8 are arranged within the finder optical system, so that the image magnifications of the photographing system and the finder system are equally balanced; In this case, the long focal length photographing lens 1 is housed in a pocket section 19 inside the outline of the camera body 3,
Further, the front end of the pocket portion 19 can be closed by the operation portion 5c of the lens support member 5 as shown in the figure.

At this time, since the long focal length photographing lens 1 is housed in the pocket section 19, the camera is more compact than in the above case.

FIGS. 3 and 4 are views showing another embodiment of this invention, in which only the long focus photographing lens 1 is pivoted at its base on a shaft 4 on a camera body (not shown). The support part 25 at the tip of one arm of the lens support member 25 is supported so that the optical axis of the photographing lens 1 is oriented in a radial direction centered on the axis 4 in a focus adjustable manner, and the other lens support member 25 is used for standard photography, for example, for normal photography. The lens 2 is mounted on a sliding base plate 20 that is slidably provided on the camera body, and its protrusion 20a is engaged with a fork portion 25b at the tip of the other arm of the lens support member 25. Within a certain rotation angle range of 25, the photographing optical path axis is moved between the standard photographing possible position (Fig. 4) where the optical axis is aligned with the photographing optical path axis and the retracted position (Fig. 3) where the optical axis is retracted out of the photographing optical path. It is designed to be operated in a direction perpendicular to the

The distance between the fork part 25b and the shaft 4 is the distance between the support part 25a and the shaft 4.
The distance is set shorter than that of the standard shooting lens 2.
operates behind the long focus photographing lens 1 and the dustproof cover 18.

This is because when a taking lens 2 with a relatively short focal length is used, if the taking lens 2 is rotated counterclockwise as shown in Figs. This configuration is advantageous in order to prevent the photographic lens 2 from hitting surrounding members such as the wall of the film cartridge 21 and the like, making it virtually impossible to carry out the operation.

In addition, 22 in the figure is a focus adjustment material, and each photographing lens 1,
2 is set on the photographing optical path, the focus adjustment driven protrusion 1a.

2a to rotate the helicoid ring and adjust its focus.

Further, the lens exchange operation in this embodiment is completely the same as in the embodiments shown in FIGS. The standard photographing lens 2 slides along with the rotation of the lens 25, and the long focus photographing lens 1 is stored in the pocket portion 19 during standard photographing.

Note that the same parts as in FIG. 1 are given the same reference numerals.

As explained above, according to this invention, of the two taking lenses with different focal lengths included in the camera, at least the long focal length taking lens is pivotally mounted on a shaft protruding from the camera body. The optical axis of the lens supporting member is supported in a radial direction centered on the axis, and the other short focal length photographing lens is supported behind it in conjunction with the operation of the long focal length photographing lens. When the short focal length photographing lens is set on the photographing optical path, the optical axis of the long focal length photographing lens is tilted and retracted with respect to the photographing optical path axis, and the pocket is placed in the camera body contour. Since the long focal length photographing lens is retracted, the protrusion of the front of the camera body is reduced, making it possible to make the overall size of the camera body extremely small and compact. In this respect, even when a photographic lens with a long focal length is provided, it can be sufficiently accommodated within the contour of the camera body, greatly improving the convenience of carrying the camera.

In addition, in terms of the accuracy of the lens back, this device has a rotating structure around a single point, and the lens back is determined by the radius of the lens support member that supports the photographic lens, so it is very good. It has the advantage of very high accuracy and is extremely simple in construction.

[Brief explanation of drawings]

FIG. 1 is a plan view of the main part of the embodiment, FIG. 2 is a plan view when the lens is replaced, and FIGS. 3 and 4 are perspective views showing lens replacement in other embodiments. 1.2... Photographing lens, 3... Camera body, 4... Axis, 5, 25... Lens support member, 19... Pocket section.

Claims (1)

[Scope of utility model registration request] In a small camera equipped with two photographing lenses having different focal lengths, the photographing lenses can be selectively exchanged at any time, and a lens support member is provided which is pivoted on an axis substantially perpendicular to the photographing optical path axis, At least one of the photographing lenses, which has a relatively long focal length, is mounted and supported on the support member so that its optical axis coincides with the direction of the force centered on the axis, and rotation of the lens support member causes the lens to have a relatively long focal length. The focal lens can be selectively set to a position facing the photographing optical path axis and a retracted position, and the relatively short focal length lens is linked to the rotational movement of the lens support member. A lens changing device characterized in that the lens is positioned behind the relatively long focal length lens and alternately with the relatively long focal length lens on the photographing optical path axis.