JPS5930524A - Cushioning device of mirror and diaphragm driving mechanism in single lens reflrex camera - Google Patents

Abstract

PURPOSE:To improve a silencing effect, by applying the brake to the forward movement of a mirror kicking-up means and a diaphragm means by using an air damper. CONSTITUTION:A piston 41 connected to a mirror kicking-up lever 8 moves slidingly in a cylinder 42 and the movement thereof is decelerated by receiving the brake of air resistance in the stage of the simultaneous operation of a mirror-up and aperture mechanism. On the other hand, the turning or movement of the member 8, a mirror-up lever 11, a driving means 1, an aperture lever 2 and a preset lever 22 is braked as well. Therefore, these members are cushioned and smaller sounds are produced. The movement of the piston 41 connected to the lever 8 in the cylinder 42 is also braked by air resistance and smaller sounds are produced in the stage of resetting of the mirror and the diaphragm mechanism. Since the forward end part 41a of the piston 41 contacts with the elastic material 44 in the cylinder 42 at the final point of the resetting of the piston 41, smaller sounds are produced.

Description

TECHNICAL FIELD The present invention relates to a shock absorber for a mirror and aperture drive mechanism in a single-lens reflex camera.

PRIOR TECHNOLOGY In general, an eye reflex camera has a configuration in which the members of the mirror drive system and the diaphragm drive system each operate instantaneously at the same time in response to the end of exposure at the shutter release operating section. As a result, the sound generated before and after exposure is much louder than a camera with a rangefinder.

To overcome these drawbacks, various noise reduction devices have been proposed in the past, but all of them attempt to reduce the sound emitted by the mirror drive system using, for example, air dampers or cushions.

However, in the various types of photographic lenses used in eye-reflex cameras, there is usually some variation in the spring force used to operate or restore the aperture, depending on the type or product of the photographic lens. The aperture drive system on the camera body side is operated with a stronger force so that the aperture operates or restores normality even if there is a flicker. As a result, the exposure [
11) Later, the sound generated by the aperture drive system usually has twice the energy of the sound generated by the mirror drive system, so even if measures are taken to silence only the mirror drive system, sufficient noise reduction effects cannot be obtained. do not have.

Also, some reflex cameras have a configuration in which manual aperture can be performed with the aperture drive system locked, and then the mirror and aperture drive system can be activated by the release operation. After manual diaphragm, the mirror and diaphragm drive system operate without load, which generates even louder noise than during normal diaphragm operation.

Purpose The present invention is to eliminate the drawbacks of such an optical reflex camera.The purpose of the present invention is to eliminate both the problems caused by the mirror drive system and the aperture drive system even when the mirror drive system and aperture drive system are operated during normal mirror flip-up and aperture operation. An object of the present invention is to provide a shock absorbing device for a mirror and aperture drive mechanism that can reduce noise generated in a drive system.

SUMMARY In the present invention, an air damper is used to brake the forward movement of the mirror bounce means and the diaphragm actuating means, thereby reducing the shear generated in the mirror drive system and the diaphragm drive system.

At this time, the mirror bounce L means and the diaphragm actuation means are simultaneously driven in the forward direction by a common drive means, and either of the drive means, ``mirror bounce'' means 2, and diaphragm actuation means Connect the movable part for braking of the air damper.

The old aperture actuation means is composed of a preset lever and an aperture actuation lever, both of which are rotatably supported, and when only the preset lever is externally operated in the direction of tightening the aperture, only the preset lever is rotated independently. In addition, a manual narrowing operation member is placed opposite to the preset lever.

EXAMPLE The structure of the present invention will be explained below with reference to the drawings shown as an example.

As shown in FIG. 1, a drive means 1 formed as a reciprocating interlocking shaft of a quick-return type mirror drive mechanism is as follows:
It is supported by a bearing on the side plate 39 of the mirror box so that it can slide in the direction of Tosuke, and is constantly moved to the left (
The long groove 1b, which is perpendicular to the sliding direction, is provided in the large diameter portion 1a of the reciprocating interlocking shaft 1 at right angles to the sliding direction. (see) arm 2
The protrusion 3 of a is fitted. Additionally, a locking piece (
There is a locking member) 4. The locking piece 4 has a slit 4a provided therein and a guide pin 5 fixed to the body.
A part of the locking piece 4 and the fixing pin 6 are connected by a spring 7, and the locking piece 4 is set at the position shown. Further, the locking piece 4 moves upward (/) by pressing a shirt button (not shown), and
It is configured to release the blockage in the left (A) direction.

An arm 1c extends from the right end of the large-diameter portion 1a of the driving means 1, and a protrusion 1d at the tip engages with a bifurcated arm 8a of a mirror jumper lever 8, which will be described later.

The mirror flip lever 8 is rotatably attached to a shaft 9 protruding from the mirror box, and the mirror flip lever 1 is rotatably attached to the same shaft 9 as the mirror flip lever 8.
1 is constructed so that the levers 8 and 11 can be rotated together by a spring 13 that connects the two levers 8 and 11 via a pin 12 protruding from the mirror up 1/bar 11. , 11 form a mirror bouncing means.

The mirror 15 is rotated 1'+J around the axis J6 (, t ij
and a spring 17 and an N" stop pin 18 which are connected to a part thereof.
The second end surface 14 of the mirror up lever 11 and the pin 19 protruding from the mirror 15 can be engaged with each other.

Air 9” pump 40 has piston 41 and cylinder 4
The piston 41 is slidable in the cylinder 42 and constitutes a braking member of the air gun bar. It is connected to one end 1o. The shilling 42 is pivoted to the wall of the mirror box with a pin 43. Further, inside the cylinder 42, there is provided an elastic body 44 that causes the piston to move back (at one time colliding with the tip end 41b of the piston 41).

At a position corresponding to the mirror up lever 11, there is a manual mirror up interlock lever 3 that can be operated from outside the camera body.
1, and the interlocking lever 31 rotates by one rotation about the shaft 32, and is normally biased clockwise by a spring 33.

In FIG. 2, an inverted T-shaped aperture operating lever 2 having a protrusion 3 engaged with a long groove 1b of a large diameter portion 1a of a drive means 1 can be rotated by a fixing pin 21 fixed to a mirror box. A portion of the left arm 2c and the mirror box are connected by a spring 2o, giving the aperture operating lever 2 the ability to rotate counterclockwise. Also,
A preset lever 22 that interlocks with the lever 2 is rotatably attached to a fixing pin 23 fixed to the mirror box.
4 and a pin 25 protruding from the right arm of the preset lever 22.
are connected by a connecting piece 26, and a hook 26a opened on one side of the connecting piece 26 and a pin 25 protruding from the preset lever 22 are loosely engaged so that they are interlocked in only one direction.

Further, the right end 22b of the preset lever 22 is protruded from the rear end 30 on the side of the interchangeable photographing lens 28o) which incorporates a known automatic preset diaphragm device (not shown), and the automatic preset diaphragm It engages with an aperture interlocking pin 29 which is always biased in one direction (in the aperture direction) by a spring 27 within the device.

The aperture operating lever 2 and preset lever 22 are
A spring (no figure number) and connecting piece 26 that connects them at one end
Together, they constitute an aperture operating means.

At a position opposite to the preset lever 22, there is formed a protruding piece 38 provided on a manual diaphragm slide 37 which can be operated from outside the camera and is movable in the L direction in FIG.

1. A mirror and aperture restoring lever 34 is provided at a position corresponding to the right end 2b of the lever 2, and the restoring lever 3
The lever 4 is configured to rotate 11 times around a fulcrum 35, and is configured to push back the right end 2b of the lever 2 by the biasing force of a spring 36 when the exposure of the shutter is completed.

This embodiment adopts the configuration as described in L, so when performing normal photography (automatic aperture photography), if you first press the shirt button (not shown), the locking tab on the side of the mirror box will appear in Figure 1. 4 is guided by the guide pin 5 and moves upward ( ) against the spring 7 , and when the locking piece 4 locks the driving means 1 , the driving means 1 moves in the direction of the arrow ( ). Due to this movement of the drive means 1, the lever 8 rotates clockwise, and the lever 8 rotates clockwise.
The mirror up lever 11, which is interlocked with the mirror up lever 11, is rotated clockwise to raise the mirror 15 via the pin 19 (see FIG. 3).

During this time, in FIG. 2, the left side (A) of the driving means 1 is
The aperture operating lever 2, which is fitted into the long groove 1b of the driving means due to the movement in the direction, rotates counterclockwise about the shaft 21, and the preset lever 22, which is connected to this lever by a connecting piece 26, similarly rotates counterclockwise. As it is rotated clockwise, the tip 22b of its right arm moves in one direction, and the aperture interlocking pin 29 that abuts the tip 22b moves upward,
The aperture of the photographing lens 28 having an automatic preset aperture device is narrowed down to a predetermined value (see FIG. 4).

When the mirror amplifier and aperture mechanism described above operate simultaneously, the piston 41 connected to the lever 8 shown in FIG. 2 is member 8, mirror up lever 1.
1. The driving means 1, the aperture operating lever 2, and the preset lever 22 are also subject to braking in their rotation or movement. That is,
These members are damped, thereby reducing the noise generated.

When the mirror 15 is completely raised, the shutter as shown in FIG. 7 is operated to perform a predetermined exposure. At the same time, the mirror and diaphragm restoring lever 34 or the splinter 36 is actuated to move the driving means 1 to the right (in the direction of Q in FIG. Since the mirror up lever 11 is rotated in the direction 71, the mirror up lever 11 which is interlocked therewith is also rotated counterclockwise in the direction 71, and the mirror 15 returns to the original finder position determined by the spring 17 and the blocking pin 18.

Similarly, in FIG. 2, the aperture operating lever 2 is rotated clockwise and the brisset lever is activated via a spring (not numbered).
22 in the clockwise direction, and
Push down the right arm tip 22b or the aperture interlocking pin 29 to open the aperture again.

When the above-mentioned mirror and aperture mechanism return, the piston 41 connected to the lever 8 slides in the (O) direction within the cylinder 42, but this movement is also braked by air resistance. Ru. In this case as well,
Each moving member is damped, reducing the noise generated. Note that at the final point of the return sliding movement of the piston 41, the tip end portion 418a of the piston 41 comes into contact with the bullet body 44 provided in the cylinder 42, so that the contact between the piston 41 and the inner wall of the cylinder 42 is Sound generation due to collisions is also reduced.

When performing manual mirror-up photography, as shown in FIG. Rotate to mirror 15
or rise. After manually raising the mirror in this way, when the locking piece 4 is activated, the aperture operating lever 2,
The preset lever 22 rotates to narrow down the aperture of the photographing lens 28 to a predetermined value, and the driving means 1 and lever 8 also operate to raise the mirror, but this is not the case in manual mirror close-up photography. The mirror jump slides within the piston 41 or cylinder 42 connected to the Renocou 8 while being braked, and gently moves the drive stage 1q9.

In addition, when performing manual aperture photography, as shown in FIG. 6, when the sliding member 37 is pushed from j'fi≦ outside the camera to the L force, the tip 22b of the 71 arm of the preset lever 22 is moved upward. The diaphragm interlocking pin 29 that is aligned with the right arm end 22b at Mj moves upward to narrow the automatic precent diaphragm to a predetermined value, and this state is maintained by a mechanism (not shown). When the locking piece 4 is operated after performing such L-motion aperture reduction, the aperture operating lever 2, the driving means 1, the mirror jumper 42 are activated by the lever 8, and the mirror up lever 11.
However, even in such manual aperture shooting, the mirror 15 slides under braking inside the piston 41 or cylinder 42 connected to the mirror flip-up lens 8. This is to buffer the driving means 1 and the like.

It should be noted that the present invention is described as one embodiment in which the C1 air damper 40 is connected to the mirror lever 8. However, the present invention is not limited to this, and the C1 air damper 40 is used as a drive for operating the mirror and the diaphragm. part, that is, the aperture operating lever 2
It goes without saying that the driving means 1 and the mirror flip-up may be configured to be interlocked with any one member of the lever 8.

Effects In the present invention, as described above, a driving means is provided for linking and driving the mirror jumping means and the aperture operating means so that they move forward, and the driving means and the mirror jumping means are also provided. By connecting a movable braking part of the air damper to either the driving means, the diaphragm actuating means, or the diaphragm actuating means, both of the driving means, the mirror jump means, and the diaphragm actuating means can be damped during their forward movement. As a result, not only the noise generated by the mirror drive system but also the noise generated by the diaphragm drive system can be reduced, and as a result, a noise reduction effect can be achieved.

In addition, the aperture actuating means is composed of a preset lever and an aperture operating lever, and both levers are connected by a spring, so that only the preset lever can be rotated in the aperture direction using the manual aperture member. Regardless of the position of the preset lever, the air damper acts on the driving means, the mirror jumping means, and the diaphragm actuating member, so the generation of noise caused by the forward movement of these members or means is effectively suppressed. I can do it.

[Brief explanation of the drawing]

FIG. 1 is an enlarged side view of the essential parts of an embodiment of the shock absorbing device of the present invention, showing the state before the mirror is raised. FIG. 2 is a bottom view of FIG. 1, showing a state in which the automatic aperture operating mechanism or the lens aperture is in an open state. FIG. 3 is an operation explanatory diagram showing the operating state of FIG. 1, and shows a state in which the mirror is amplified. FIG. 4 is an operation explanatory diagram showing the operating state of FIG. 2, and shows a narrowing down state. FIG. 5 is an explanatory diagram showing a state in which the mirror is manually raised in FIG. 1. FIG. 6 is an explanatory diagram showing a manually narrowed-down state in FIG. 2. 1... Drive means, 8.11... Peller bouncing ball is means,
2.22... Aperture operation means (2... Aperture operation reno<
-, 22...) 17 set lever), 40... Air damper f- (41... Braking movement part), 4... Locking part lever, 37... Manual narrowing member, 29...・Aperture interlocking member. Applicant Minolta Camera Co., Ltd. No. 1 Figure 3 Figure 4

Claims (1)

[Scope of Claims] In response to the release operation, the mirror bounce means and the aperture operating means are moved forward to perform the mirror bounce L and the aperture stop, and in response to the end of exposure, ”
In a single-lens reflex camera in which the mirror bounce means and the aperture actuating means are moved back to lower the mirror and return the aperture to a fully open state, the aperture actuating means is Throttle operation j'KI
It is composed of a preset lever that engages with the S material, and an aperture operating lever that is connected to the same lever so as to allow this preselection, and an air damper that has a movable part for braking; In order to move the operating lever forward at the same time, there is a drive means that connects and drives the mirror flip-up means and the diaphragm actuating member, and this drive means is locked to prevent its operation, and the drive means is locked in response to the release operation. A locking member for releasing the lock, and a manual aperture member for rotating the preset lever in the aperture direction by external operation in a state before the forward movement of the L mirror flip-up means and the aperture operating means. A shock absorbing device for a mirror and aperture mechanism, characterized in that a movable braking portion of an air damper L is connected to any one of the mirror flip-up means, the aperture operating lever, and the drive means.