JPH0334734Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a mount adapter that is installed between the body of a single-lens reflex camera and an interchangeable lens, and is particularly applicable to interchangeable lenses that have a photometry interlocking member for TTL aperture metering. There are two types: one that does not have any parts and is only for stop-down photometry, and if the camera body to which this interchangeable lens is attached is equipped with a photometry interlocking member that interlocks with the photometry interlocking member of the interchangeable lens, each replacement The present invention relates to a mount adapter that allows automatic switching between wide-open photometry and closed-down photometry using a lens.

As is well known, TTL metering for single-lens reflex cameras is
If the interchangeable lens has an automatic aperture structure, the interchangeable lens is provided with an aperture interlocking member that rotates together with the aperture value preset ring, and this aperture interlocking member is linked to the photometry interlocking member provided on the camera body. Generally, wide-open photometry is used to provide preset aperture information on the body side. However, it is difficult to use an automatic aperture structure for special interchangeable lenses such as shift lenses, reflective lenses, or certain accessories such as bellows, so photometry is performed while the attached lens is stopped down. It is necessary to perform focusing photometry.

By the way, the photometry interlocking member on the camera body side is rotationally biased in one direction, and this urging force causes it to come into contact with the aperture interlocking member of the interchangeable lens. A type that can be restored to its original position by applying force (for example, Pentax 6x7 in the applicant company's products)
There is also a type (K mount camera) that can be moved to the maximum position against the biasing force.
For this reason, if you attach an interchangeable lens or accessory that does not have an aperture interlocking member to the latter type of body, such as a lens that requires aperture metering, the body-side photometry interlocking member will not move.
There were times when I was unable to perform aperture metering.

In view of these circumstances, the present invention has been devised to develop a camera body of the latter type, that is, a camera body that enables stop-down photometry when the photometry interlocking member for TTL photometry is moved to the moving end side that resists the biasing force. To,
This mount adapter was designed to enable aperture metering when an interchangeable lens without an aperture linking member is attached, and to enable aperture metering when an interchangeable lens with an aperture linker is attached. It is.

In order to achieve this purpose, the mount adapter of the present invention engages with the photometry interlocking member of the camera body in conjunction with the rotating operation of mounting on the camera body,
A stop-down photometry position holding lever rotates the photometry interlocking member and holds it at the stop-down photometry position, and an aperture interlocking member for TTL open metering of the interchangeable lens rotates together in conjunction with the rotating operation of attaching the interchangeable lens. When the camera body is moved, an interlocking ring is provided, and in conjunction with the rotation of the interlocking ring, the focus-down photometry position holding lever is swung to release the restraint of the camera body-side photometry interlocking member by the lever. It is a feature. In other words, when an interchangeable lens without an aperture interlocking member is attached, the interlocking ring does not rotate, so the photometry interlocking member on the camera body side is held at the aperture metering position, enabling aperture metering, and the aperture interlocking member When a certain interchangeable lens is attached, the photometry interlocking member on the camera body side is released, allowing open photometry. When the photometry interlocking member on the camera body side is released, the camera body side photometry interlocking member and the interchangeable lens side diaphragm interlocking member are adapted to interlock with each other.

The invention will now be described with reference to the illustrated embodiments. This example uses the K-mount camera body mentioned above.
It is designed to be equipped with a Pentax 6x7 interchangeable lens. In Figures 1 to 3, 11 is the K mount (female) on the camera body, and 12 is the 6x7 mount on the lens side. (male). The mount adapter of the present invention has a bayonet ring 13 (male mount) attached to the K mount 11 and a mount ring (female mount) 14 attached to the 6x7 mount 12. 14 is fixed by a fixing screw 15. An interlocking ring 16 is rotatably fitted between the bayonet ring 13 and the mount ring 14, and an interlocking protrusion 19 having an interlocking surface 18 that engages with the diaphragm interlocking member 17 of the interchangeable lens is integrated into the interlocking ring 16. It is formed. Further, a linking plate 22 is fixed to the rear surface of the linking ring 16 by a fixing screw 21, and a linking protrusion 2 that has an interlocking surface 24 with a photometry linking member 23 on the camera body side is attached to the linking plate 22.
5 is provided to protrude inwardly, and furthermore, a focusing photometry holding surface 26, a photometry mode switching slope 27, and an open photometry holding surface 28 are formed on its inner peripheral surface. The linking plate 22 equipped with the above elements is the linking plate 22
Spring hook screw 29 installed in and bayonet ring 1
A tension spring 31 is tensioned between the spring hook 30 and a spring hook 30 installed in the spring 3, and the tension spring 31 is biased to rotate in the direction of arrow A in FIG. A spring roller 32 guides the tension spring 31, and is rotatably supported by the linking plate 22 by a spring roller shaft 33.

On the other hand, a stop-down photometry position holding lever 36 is pivotally attached to the bayonet ring 13 with a shaft screw 35. The stop-down photometry position holding lever 36 has its free end bent into a substantially L-shape, and an engagement surface 37 that engages with the photometry interlocking member 23 on the camera body side is formed at its tip. Further, a follower 39 is rotatably supported by a roller shaft 38 at the L-shaped bent portion. This focusing photometry position holding lever 36 is connected to the photometry interlocking member 22 by a switching spring 40 provided around the shaft screw 35.
The follower 39 is urged to rotate in the direction of engagement with the link plate 22, that is, in the direction of arrow B in FIG.
The linking plate 22 is normally urged to rotate in the direction of arrow A in FIG. At this time, the engagement surface 37 of the focus-down photometry position holding lever 36 is rotated to a position where it can engage with the photometry interlocking member 23 .

The photometry interlocking member 23 on the camera body side is the first
It is movable by an angle θ ₁ shown in FIGS.
In the free state, the rotary end 23a is biased to rotate in the direction of arrow C (FIG. 5). And as mentioned above,
When this interlocking member 23 is moved to the maximum position against the rotation biasing force and positioned at the opposite moving end 23b, a state in which focusing photometry is possible is achieved. The notch 41 of the bayonet ring 13 is provided in the range in which the photometry interlocking member 23 and the interlocking protrusion 25 rotate.
In addition, the angle θ ₂ in Fig. 1 indicates the range in which the diaphragm interlocking member 17 on the interchangeable lens side moves when the interchangeable lens is attached to this adapter, and the angle θ ₃ indicates the range from which the aperture linking member 17 on the interchangeable lens side moves from the closed-down metering state to the open metering state. The rotation angle of the interlocking plate 22, that is, the interlocking ring 16 required for the movement is shown. This θ ₃ is the forming angle range of the photometry mode switching slope 27 .

Although not shown, the bayonet ring 13
An automatic diaphragm transmission member for interlocking the camera body and the automatic diaphragm mechanism of the interchangeable lens is separately installed by known means. The thickness d of this adapter is determined so that when a 6×7 interchangeable lens is connected to a K-mount body, the flange backs of both lenses match.

This adapter with the above configuration can be used either by attaching the 6×7 mount 12 of the interchangeable lens to the mount ring 14 and then attaching the bayonet ring 13 to the K mount 11.
The bayonet ring 13 is first attached to the K mount 11, and then the 6×7 mount 12 is attached to the mount ring 14. To explain the latter as an example, the bayonet ring 13 is K
When it is fitted into the mount 11, the photometry interlocking member 23 and the engagement surface 37 of the stop-down photometry position holding lever 36 are in a state where they can engage with each other, as shown in FIG. The follower 39 of the stop-down photometry position holding lever 36 engages with the stop-down photometry holding surface 26, and holds the engagement surface 37 at a position where it can engage with the photometry interlocking member 23. In this state, when the bayonet ring 13, that is, the adapter is rotated in the direction of arrow D in the figure, the photometry interlocking member 2
3 are both rotated in the D direction by the engagement surface 37, and when the photometry interlocking member 23 is finally fixed, the photometry interlocking member 23 is rotated to the end of its movement against the biasing force as shown in FIG. In other words, at this time, focus-down photometry becomes possible.

Mount ring 14 of this adapter in this state now
When an interchangeable lens or accessory that does not have the aperture interlocking member 17 is attached, the lens or accessory that does not have the aperture interlocking member 17 does not have a means for engaging with the interlocking protrusion 19, so the interlocking plate 22 is in the state shown in FIG. is maintained. Therefore, since the focusing photometry position holding lever 36 does not change its position, the photometry interlocking member 23 that engages with the engagement surface 37 is also held at the position shown in FIG. can be done.

On the other hand, an interchangeable lens or accessory for aperture metering having an aperture interlocking member 17 is attached to the mount ring 1.
4, the diaphragm interlocking member 17 connects to the interlocking protrusion 19.
Since the interlocking protrusion 19 is pushed by the diaphragm interlocking member 17 due to the relative rotation of the 6×7 mount 12 and the mount ring 14, the interlocking plate 22 moves in the direction opposite to the arrow A in FIG. Rotate in the direction of.
Then, when the link plate 22 first rotates by θ ₃ ,
The photometry mode switching slope 27 on the inner peripheral surface of the linking plate 22 pushes down the follower 39, and as a result, the focusing photometry position holding lever 36 swings in the direction opposite to the direction of arrow B in FIG. The engagement of the photometry interlocking member 23 is released. The follower 39 then comes into contact with the open photometry holding surface 28 and maintains this disengaged state. Therefore, the photometry interlocking member 23 moves according to the biasing force and comes into contact with the interlocking surface 24 of the interlocking protrusion 25 as shown in FIG. In other words, the diaphragm interlocking member 17 on the interchangeable lens side and the photometry interlocking member 23 on the camera body side are interlocked by the two interlocking protrusions 19 provided on the interlocking plate 22 and the interlocking surface 24, making open photometry possible. It is.

First attach the 6x7 mount 12 to the mount ring 14, then attach the bayonet ring 13 to the K mount 11.
The interlocking relationship is exactly the same as above when it is attached to the holder. However, if the 6×7 mount 12 is attached to the mount ring 14 first, the engagement surface 37 of the focus-down photometry position holding lever 36 will be attached to the photometry interlocking member 23 in that state.
When the bayonet ring 13 is mounted on the K mount 11, the interlocking surface of the photometry interlocking member 23 and the interlocking protrusion 25 is moved as the bayonet ring 13 rotates in the direction of arrow D. 24 come into contact immediately (see Figure 8).

In the above embodiment, the present invention is applied when an interchangeable lens with a large screen size is attached to a camera body with a small screen size.
Even if the interchangeable lens and camera body have the same screen size, they can be similarly used as a mount adapter for close-up photography.

As described above, the single-lens reflex camera mount adapter of the present invention includes a photometry interlocking member for TTL open photometry that is rotationally biased on either side, and the photometry interlocking member moves against the biasing force. For camera bodies that enable stop-down metering when moved to the edge, we recommend using an interchangeable lens or accessory for open metering that has a metering interlocking member, and an interchangeable lens or accessory for stop-down metering that does not have a metering interlocking member. When selected and installed, the effect can be obtained that it is possible to automatically switch to the open photometry state and the closed-down photometry state. Furthermore, according to the mount adapter of the present invention, there is no need to provide any members or processing to the camera body and photographic lens, so it can be used as is for existing camera bodies and existing interchangeable lenses.

[Brief explanation of the drawing]

Figure 1 is a front view of the main parts showing an embodiment of the mount adapter of the present invention, Figures 2 and 3 are sectional views taken along lines - and - in Figure 1, respectively, and Figure 4 is focused photometry. Figure 5 is an exploded perspective view of the position holding lever part, Figure 5 is a front view of the main part showing the position and rotation range of the photometry interlocking member on the camera body side, Figures 6 and 8 are respectively showing how the mount adapter is attached to the camera body. FIG. 7 is a front view of the main parts in different states showing the mounted state, and FIG. 7 is a front view of the main parts when the state shifts to the state where open photometry is performed. 11...K mount (camera body side mount), 12...6x7 mount (interchangeable lens side mount), 13...bayonet ring, 14...mount ring, 16...interlocking ring, 17...diaphragm interlocking member (Interchangeable lens side), 19, 25... Interlocking protrusion, 22
... Linking plate (linking ring), 23... Photometry interlocking member (camera body side), 26... Focusing photometry holding surface, 2
7...Photometry mode switching slope, 28...Open photometry holding surface, 31...Tension spring, 36...Fitting down photometry position holding lever, 37...Engagement surface.

Claims (1)

[Scope of claim for utility model registration] A photometry interlocking member for TTL open photometry that rotates in conjunction with an aperture interlocking member for TTL open photometry of the interchangeable lens, and this photometry interlocking member is biased to rotate in either direction. A single-lens reflex camera that is attached between a camera body that enables stop-down photometry when the camera body is moved against the biasing force toward the moving end corresponding to the open aperture state of the interchangeable lens, and an interchangeable lens. A mount adapter for a camera, which engages with the photometry interlocking member in conjunction with rotational operation when attached to the camera body, and rotates the photometry interlocking member to a moving end side corresponding to an open aperture state of the interchangeable lens. a stop-down photometry position holding lever that is moved and held at the stop-down photometry position; and a stop-down photometry position holding lever that is moved and held in the stop-down photometry position; a ring; a photometry method switching means for swinging the stop-down photometry position holding lever in conjunction with the rotating operation of the interlocking ring, and releasing the restraint of the photometry interlocking member of the camera body by the lever; the photometry method switching means A mount adapter for a single-lens reflex camera, comprising: interlocking means for interlocking the photometry interlocking member and the aperture interlocking member of the interchangeable lens when the photometry interlocking member of the camera body is released.