JPS6039212B2 - Lens mounting device for lens shutter type cameras - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shutter mounting device for a shutter shutter type camera.

Lens-shutter cameras have a shutter built into the lens barrel of the interchangeable lens, so when the interchangeable lens is attached to the camera's lens mount, the shutter drive mechanisms on the camera side and the interchangeable lens side are connected. There is.

To drive the lens shutter, it is necessary to reciprocate the connecting pin on the camera side (to operate the shutter in reciprocating motion, and to charge the shutter in the backward motion), so the engagement part on the camera side and the connecting pin on the camera side The connecting pin must be connected so that the connecting pin on the lens side is pushed by the engaging member on the camera side in both reciprocating motions against the load for driving the shutter mechanism. Therefore, when attaching a lens to a camera, first engage the connecting pin on the lens side in a predetermined position of the engaging member on the lens side, restrain the forward and backward movement of the connecting pin, and then separate the lens without rotating it. The lens had to be fixed to the camera using a fixing means. A specific mounting device for this type of lens that has been used in the past involves creating a notch in the camera shutter drive ring, positioning it so that the lens connecting pin fits within this notch, and then The spigot bayonet mount is known in which the lens barrel is dropped onto the lens mount, the shutter drive ring on the camera side and the continuous pin on the lens side are connected, and then the tightening ring is turned to secure the interchangeable lens to the camera. ing. However, lens-shutter cameras have large camera bodies and interchangeable lenses, and are quite heavy. Therefore, when attaching an interchangeable lens, this spigot bayonet mount allows you to hold the lens with one hand while holding the lens with the other hand. This had the disadvantage that it was difficult to change lenses because the tightening ring had to be turned by hand. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks, and to provide a lens attachment device for a lens-shutter camera that allows easy attachment of an interchangeable lens. The present invention provides a fixed pin and a movable pin on the shutter drive ring on the camera side, and when an interchangeable lens is attached to the lens mount of the camera, the movable pin is retracted to allow the lens barrel to rotate. After rotating the lens by a predetermined amount, the connecting pin on the lens side is supported by the fixed pin of the shutter drive ring on the camera side, and the movable pin that was retracted at that time is pushed out. A feature of the present invention is that a lens-side connecting pin is held between the movable pin and the fixed pin, and the camera-side shutter drive ring is connected to the shutter drive ring so as to be reciprocally driven.

Furthermore, when the lens barrel is stacked on the lens mount, the lock pin that locks the lens attachment is retracted into the lens mount, and the movable pin is also retracted in conjunction with this, so that when the interchangeable lens is rotated, the lock pin locks the lens. aligns with the notch provided at the end of the lens barrel, the connecting pin provided on the lens-side shutter drive ring is in a position past the movable pin, and the lock pin protrudes into the notch due to spring force. The movable pin then protrudes in conjunction with this, and the connecting pin is held between it and the fixed pin. Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a perspective view of the interchangeable lens in the shutter set state, and the interchangeable lens includes a lens barrel 2.
A plurality of bayonet claws 3 bent outward are fixed to the rear end portion 2a of this lens barrel 2.

A pair of protrusions 4 and 5 are located inside this bayonet claw 3.
is provided. A guide rail 6 and a notch 7 adjacent to the guide rail 6 are formed on the same radius as the projections 4 and 5. Further, a pair of annular holes 8 and 9 are bored in the rear end 2a of the lens barrel 2, and connecting pins 11 and 12 are installed through the annular holes 8 and 9 to connect the lens side shutter drive ring 0'. protrudes at a symmetrical position with respect to the center of the lens barrel. In the state shown in FIG. 1, the shutter is in a set state, and the connecting pins 11 and 12 are located at the counterclockwise ends of the rotatable ranges along the annular holes 8 and 9, respectively. FIG. 2 is a front view of the lens mount on the camera side, and a lens mount 14 is provided on the front of the camera body 13.

A plurality of bayonet claws 15 that engage with the bayonet claws 3 are provided on the lens mount 14 so as to be bent inward. A lock pin 17 and a stop pin 18 are provided inside the bayonet pawl 15.
The lock pin 17 is provided in the camera body 13 so as to be urged to protrude and retract by a spring force.
It projects into the notch 7 of the lens barrel 2. A stop pin 18 is fixed to the camera body 13 and collides with one of the stoppers 4 and 5 to restrict rotation of the lens barrel 2. A camera-side shutter drive ring 19 is rotatably provided inside the camera body 13, and a pair of fixing pins 20 and 21 are fixed to this shutter drive ring 19 at symmetrical positions with respect to the center of the ring. ing.

These fixed pins 20 and 21 are connected to the connecting pins 11 and 12.
It is supposed to touch and press this. A movable pin 22 that is biased to protrude is provided at a position on the same radius as the fixed pin 21 and separated by the width of the connecting pin 11 or a length slightly larger than the width of the connecting pin 11 so as to be freely protrusive and retractable. Third
As shown in detail in the figure, when an externally operable lock release button 23 is pressed, the lock pin 17 and movable pin 22 are retracted in conjunction with this. That is, the lock release button 23 is slidably supported by the support portion 24 of the camera body 13, and the release lever 25 is fixed to the lock release button 23. The lock pin 17 is also slidably supported by the support portion 24. The above-mentioned release lever 25 is fixed to this lock pin 17, so that the lock pin 17 and the lock release button 23 are interlocked. A spring 26 is mounted on the lock pin 17 between the release lever 25 and the support portion 24. A flange 27 is provided at one end of the movable pin 22, and one end of a release lever 25 comes into contact with the inside of this flange 27. As a result, the lock release button 23 or the lock pin 17 is retracted (third
The movable pin 22 moves in conjunction with the stone movement (in the figure).
It is designed to be pulled inside. The movable pin 22 is inserted into a spring case 29 containing a spring 28 (see FIGS. 4 to 7), and the spring 28 biases the movable pin 22 in the direction of protrusion via a spring receiver 30. . Next, the operation of the present invention constructed as described above will be explained with reference to FIGS. 4 to 7.

Figure 4 shows the state in which the interchangeable lens is inserted into the lens mount.
The interchangeable lens 1 is stacked on the lens mount 14 so that the mark 32 (see FIG. 1) carved on the lens barrel 2 of the interchangeable lens 1 matches the position (see FIG. 2). As a result, as shown in FIG.
The lock pin 17 is always in contact with the guide rail 6 and is pushed inward. When the lock pin 17 is pushed in, the movable pin 22 is pushed inward by the release lever 25, compressing the spring 29. Thereby, the movable pin 22 is maintained in the retreated position. Next, if the interchangeable lens is rotated in the direction of the arrow in FIG.
5, and through this bayonet connection, the interchangeable lens 1
is tightly attached to the lens mount 14.

At this time, the notch 7 is inserted into the lock pin 1 as shown in FIG.
7, and the connecting pin 11 has passed through the movable pin 22 and is in contact with the fixed pin 21. lock pin 17
When the movable pin 22 protrudes and engages with the notch 7, the movable pin 22 follows the release lever 25 and protrudes due to the force of the spring 28. Therefore, the connecting pin 11 is provided between the movable pin 22 and the fixed pin 21. This completes the installation of the interchangeable lens. FIG. 6 shows the state in which the shutter is activated (after the reciprocating movement of the connecting pin 11). When the camera-side shutter drive ring 19 rotates, the movable pin 22 and the fixed pin 21 The lens-side shutter drive ring 10 is rotated through the connecting pin 11 held between the two.

When the lens-side shutter drive ring 10 rotates, the shutter opens and closes for predetermined exposure (first closes, flips up the light-shielding plate in front of the film, then opens for the exposure time, and closes), and at the same time, the movable pin 22 flange 27
comes off from the tip of the release lever 25. As a result, even if the lock release button 23 is pressed, the movable pin 22 does not retract, so the interchangeable lens 1 cannot be removed. This prevents the lens 1 from being removed with the light-shielding plate flipped up and the film after photography being inadvertently exposed. After the shutter is operated, by turning a film release and shutter setting knob (not shown), the camera-side shutter drive ring 19 is rotated to the position shown in FIG. 7.

FIG. 7 shows the set state in which the interchangeable lens can be removed from the camera. At this time, the fixing pin 2 is linked to the camera side shutter drive ring 19.
0 and the connecting pin 12, and the fixing pin 21 and the connecting pin 11, the lens side shutter drive ring 1
0 rotates and the shutter opens in preparation for shooting.
Immediately before the shutter is opened, the light shielding plate descends to shield the film from light. This returns to the state shown in FIG. When the winding operation is performed as described above, the light shielding plate descends to shield the film from light, so that the interchangeable lens 1 can be removed.

That is, when the lock release button 23 is pressed as shown in FIG. 7 in this state after winding up (FIG. 5), the lock pin 17 is released.
Then, the movable pin 22 is retracted. In this state, if you rotate the interchangeable lens 1 in the opposite direction to the above, the bayonet claw 3
and 15 are disengaged, and the interchangeable lens 1 can be removed. As is clear from the detailed explanation above,
According to the present invention, the fixed pin and the movable pin are provided on the shutter drive ring on the camera side, and when the interchangeable lens is attached to the lens mount, the movable pin protrudes, and the movable pin and the fixed pin are attached to the shutter drive ring on the lens side. Since the provided connecting pin is clamped, the camera-side shutter drive ring and the lens-side shutter drive ring are connected by simply inserting the lens barrel into the lens mount and turning it. Therefore, the interchangeable lens can be attached easily and quickly.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. I is a perspective view of the lens barrel, FIG. 2 is a front view of the lens mount, FIG. 3 is a perspective view of the main parts, and FIG. Figure 5 is a developed view showing the state in which the lens is inserted into the lens mount, Figure 5 is a developed view showing the state in which the interchangeable lens is attached, Figure 6 is a developed view showing the state after the shutter is activated, and Figure 7 is the developed view showing the state in which the interchangeable lens is removed. FIG. 1... Interchangeable lens, 2... Lens barrel, 7.
... Notch, 10 ... Lens side shutter drive ring, 11, 12 ... Connection pin, 14 ... Lens mount, 17 ... Lock pin, 19 ... Camera side Shutter drive ring, 20, 21...
Fixed pin, 22...Movable pin. FIG. l FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 6 FIG. 7

Claims (1)

[Claims] 1. In an attachment/detachment mechanism for an interchangeable lens with a built-in lens shutter, the fixing pin 21 of the camera-side shutter drive ring 19 and the fixing pin 21 are arranged close to the fixing pin 21;
A protruding and biased movable pin 22 is provided to protrude and retract in conjunction with the protruding and biased lock pin 17, and when the interchangeable lens 1 is attached to the lens mount 14 on the camera side, the pin 22 is movable in conjunction with the lock pin 17. Retract the movable pin 22,
When the interchangeable lens 1 is rotated and the lock pin 17 protrudes into the notch 7 provided at the rear end of the lens barrel 2 of the interchangeable lens 1, the movable pin 22 protrudes in conjunction with this, and the movable pin 21 and the movable pin 22 protrude. A lens mounting device characterized in that a connecting pin 11 provided on a lens-side shutter drive ring 10 is held between a pin 22.