JPH01293330A - Camera with vertically traveling focal-plane shutter - Google Patents

Abstract

PURPOSE:To shorten the full height of a camera in order to miniaturize by closing the optical axis of a finder optical system to the optical axis of a photographic optical system, thereby placing a finder in a low position. CONSTITUTION:Normally a first blind 6(a) is sin such a position where it covers an exposure opening 2(a) and a second blind 6(b) is in a retreat position below the exposure opening 2(a); finder luminous flux is not intercepted by the first blind 6(a) and second blind 6(b). When a shutter is activated, the first blind 6(a) retreats from the area of the exposure opening 2(a) in order to expose it and is also driven to a storage position above the exposure opening 2(a), the position where a part of the first blind 2(a) enters the area of a finder optical path, thereby intercepting at least a part of the finder luminous flux. After delaying time corresponding to a required shutter speed since the first blind 6(a) was activated, the second blind 69b) is driven to cover the exposure opening 2(a) whereupon exposure operation is completed and the blinds return to the normal condition. Since the finder optical axis is closed to the photographic optical axis, the full height of the camera can be shortened and the camera can be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a camera equipped with a vertically running focal plane shutter, and more particularly, the present invention relates to a camera equipped with a vertically running focal plane shutter, and more specifically, a focal plane shutter that covers a film exposure aperture. and a rear curtain disposed in a lower storage position retracted from the exposure aperture,
when the shutter is activated.

The front curtain is retracted from the exposure aperture area to expose the exposure aperture and is stored above the exposure aperture, and after a delay time corresponding to a required shutter time has elapsed, the rear curtain is moved to the exposure aperture. The present invention relates to a camera equipped with a vertically running focal plane shutter that is driven and controlled to cover the subject.

[Conventional technology]

In general, focal plane shutter cameras have been of the type in which the leading and trailing curtains run horizontally relative to the so-called Leica-sized exposure aperture, but since the curtains run in the longitudinal direction, the traveling distance is long, which results in high speeds. For example, 1/4000
It was difficult to obtain a shutter speed of about seconds. For this reason, vertically running focal plane shutters have appeared in which the leading and trailing curtains run in the short direction with respect to the exposure aperture.

This vertically running focal plane shutter (hereinafter abbreviated as "shutter") is placed at the time when shutter charging (or shutter setting) is completed, that is, the leading curtain covers the exposure aperture of the film, and the trailing curtain covers the exposure aperture. The first state (shutter set state) placed in the lower storage position
When the shutter operation is completed, that is, the front curtain is retracted from the exposure aperture area, exposes the exposure aperture, and is stored above the exposure aperture, and after the delay time corresponding to the required shutter speed has elapsed, the rear curtain is retracted from the exposure aperture area. takes a second state in which it is arranged so as to cover the exposure aperture.

In addition, since the shutter is generally designed on the premise that the shutter is charged manually, in both the first and second states, the shutter components (front curtain, rear curtain, etc.) are used to charge the viewfinder. The finder optical system is placed at a location where it does not block the finder light beam of the system.

In other words, the finder optical system is disposed at a location sufficiently distant above from the photographic optical system.

On the other hand, Japanese Patent Application Laid-Open No. 60-97327 describes a camera in which the output optical axis of a finder optical system is inclined with respect to the optical axis of a photographing optical system. This latter camera achieves this by tilting the output optical axis of the finder optical system.
We are trying to reduce the overall height of the camera as much as possible.

[Problem to be solved by the invention]

In the case of conventional cameras equipped with a vertically running focal plane shutter that is movably arranged just in front of the exposure aperture, there is a limit to how close the viewfinder optical axis can be to the exposure aperture, and as a result, the overall height of the camera has to be significantly increased. could not be reduced to

Furthermore, as described in the above-mentioned Japanese Patent Application Laid-Open No. 60-97327, even if the output optical axis of the finder optical system is tilted with respect to the photographing optical axis, the height of the camera is only slightly lowered. However, it is impossible to achieve a significant reduction in the size of the camera.

The present invention has been made in view of the above circumstances, and its purpose is to replace the conventional finder optical system without interfering with W4 observation of the viewfinder field of view despite using a vertically running focal plane shutter. This makes it possible to move the exposure aperture much closer than before, and the overall height of the camera is significantly reduced, making it much smaller than conventional cameras. An object of the present invention is to provide a camera equipped with a vertically running focal plane shutter.

[Means to solve the problem]

In order to achieve the above object, a camera equipped with a vertically running focal plane shutter of the present invention normally has a front curtain placed in a position covering the exposure aperture of the film, and a lower curtain retracted from the exposure aperture area. and a trailing curtain disposed at a retracted position, and when the shutter is operated, the leading curtain is retracted from the exposure aperture area to expose the exposure area and is stored above the exposure aperture. , a vertically running focal plane shutter that is driven and controlled so that the trailing curtain covers the exposure aperture after a delay time corresponding to a required shutter time has elapsed; and a finder optical system that is disposed near the top of the exposure aperture. and when the front curtain is retracted from the exposure aperture to expose the exposure aperture and is driven to a storage position above the exposure aperture, at least a part of the front curtain is connected to the finder optical The present invention is characterized in that it is configured to enter the finder optical path area of the system and block at least a portion of the finder light beam.

[For production]

A camera equipped with a vertically running focal plane shutter configured as described above has a finder optical system located close to the top of the exposure aperture, but in normal life, that is, before the start of shooting, the shutter is charged, the front curtain is in a position to cover the exposure aperture, and the rear curtain is in a retracted position below the exposure aperture, and the finder light flux is not blocked by the front curtain and the rear curtain, so that the viewfinder field of view cannot be observed. There are no problems.

On the other hand, when the shutter operates, the front curtain is retracted from the exposure aperture area, exposes the exposure aperture, and is driven to a retracted position above the exposure aperture, that is, a position where a part of the front curtain enters the viewfinder optical path area. Although at least a portion of the finder light flux is blocked, it is only for a moment, and since the shutter is still exposing the film, it does not cause any particular trouble.

After the delay time corresponding to the required shutter time has elapsed after the first curtain is activated, the second curtain is driven to cover the exposure aperture, the exposure operation is completed, and the shutter charging operation is subsequently performed to resume normal operation. Return to state.

As described above, by bringing the optical axis of the finder optical system significantly closer to the optical axis of the photographing optical system and disposing the finder at a lower position, it is possible to significantly reduce the overall height of the camera.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram conceptually showing an embodiment of the present invention.
Figures 2 to 4 are diagrams showing the details of the shutter section shown in Figure 1, of which Figure 2 is a plan view when the shutter charging is completed, and Figure 3 is a plan view when the front curtain has completed running. FIG. 4 is a plan view when the trailing curtain has completed running.

In FIG. 1, behind a photographic lens 1 having a photographic optical axis O, a shutter base plate 2 is provided with an exposure aperture 2a for regulating the exposure range for a film (not shown).
A movable mirror 3 for observing the photographic screen is arranged in front of the shutter base plate 2 and behind the photographing lens l at an angle of 45 degrees with respect to the photographing optical axis O. The light beam that has passed through the photographic lens 1 is bent upward by the movable mirror 3, becomes the observation light beam P, and enters the pentagonal roof prism 4, where the image is reversed horizontally and vertically. I! through the eyepiece 5! The image of the detected light flux P can be viewed in an erect state by rotating left and right in the normal direction.

On the other hand, in front of the exposure aperture 2a of the shutter base plate 2, a front curtain part 6a and a rear curtain part 6b are arranged close to each other, the details of which will be described later. A notch 2b is formed, and this notch 2b is disposed between the rear of the exit surface of the pentagonal roof prism 4 and the front of the eyepiece 5.

Although the details will be described later, this notch 2b is located at a position where it is exposed when the shutter charging of the front curtain section 6a is completed and is covered when the front curtain section 6a completes running, in other words, with respect to the photographing optical axis O of the photographic lens 1. The optical axis of the finder optical system is placed very close to the lens.

Next, details of the shutter composed of the front curtain section 6a and the rear curtain section 6b will be explained.

As shown in FIGS. 2 to 4, the shaft 7 supported by the shutter base plate 2 is given counterclockwise rotational behavior by a tension spring 8, and the stopper pin 9 fixed to the shutter base plate 2 is given a counterclockwise rotational habit. An opening release arm 10 for releasing the front curtain restraint is provided, which restricts the rotation angle range in the counterclockwise direction and has a locking pawl 10a at its tip. Also,
A shaft 11 fixedly supported by the shutter base plate 2 is provided near the opening release arm 10, and an opening slit main arm 12 formed of a thin plate member and an opening cover sub-arm 13 are stacked on this shaft 11. It is rotatably supported. Further, a shaft 14 is located below the shaft 11.
is fixedly supported on the shutter base plate 2, and this shaft 14 is also connected to the open slit main arm 12. An opening cover main arm 15 similar to the opening cover sub-arm 13, and an opening cover main arm 1-sub-arm 16 are rotatably provided in a stacked state.

The opening slit main arm 12 is provided with a claw portion 12a at its left end that is locked by the locking claw 108 of the opening release arm 10, and a drive pin 12b is fixed to the middle portion, and a drive spring is attached to the drive pin 12b. One end of the spring 17 is hung, the middle part of the spring 17 is wound around the shaft 11, and the other end is hung on a pin 18 fixed to the shutter base plate 2, causing the entire opening main arm 12 to rotate counterclockwise. Habits are given. A claw part 13a similar to the above-mentioned claw part 12a is also formed at the end of the open cover sub-arm 13 stacked on such an open slit main arm 12, and both claw parts 12a and 13a are simultaneously locked by the locking claw 10a. ing. In addition, the above-mentioned pin 1 is attached to the opening cover sub-arm 13.
2c with a predetermined play, and the opening cover sub-arm 13 is integrally moved by a pin 12e fixed on the opening slit main arm 12 through this hole 13b. It looks like this.

On the other hand, the drive pin 15 is attached to the opening cover main arm 15.
a is fixed, one end of a drive spring 19 is hung on this drive pin 15a, the middle of the spring 19 is wound around the shaft 14, and the other end is hung on a pin 18 fixed to the shutter base plate 2,
The opening cover main arm 15 as a whole is given a counterclockwise rotational habit.

Then, the pin 1 fixed to the opening cover sub-arm 13
3c and a pin 15b fixed to the opening cover main arm 15, the first blade 20 is supported by a pin 13d fixed to the opening cover sub-arm 13, and a pin 15c fixed to the opening cover main arm 15. The second blade 21 is supported, and the third blade 22 is supported by a pin 12d fixed to the open slit main arm 12 and a pin 16a fixed to the open slit sub-arm 16. It should be noted that these first to third blades 20, 21, 22 are arranged so that the adjacent blades overlap each other, and the opening slit main arm 12, the opening cover sub-arm 13. The first to third blades 20, 2 due to the respective play of the opening cover main arm 15 and the opening slit sub-arm 16.
The setting is such that the overlap of 1°22 is eliminated and so-called light ray leakage does not occur and exposure is not given.

Further, since the rear curtain section 6b has a similar structure with symmetry to that of the above-mentioned front curtain section 6a, a detailed explanation thereof will be omitted. Each part of the configuration of 6a is indicated by adding ' to the reference numeral.

In the camera equipped with the vertically running focal plane shutter according to the present embodiment configured as described above, in the normal state (state in which shutter charging is completed), the first
As shown in the figure and FIG. 2, the exposure opening 2a is completely covered by the first to third blades 20°21.22 forming the leading curtain part 6a, and the rear curtain part 6b is formed. The first to third blades 20', 21', 22'
are stored in a stacked state below the exposure aperture 2a.

At this time, the cutout portion 2b is not covered by the front curtain portion 6a, so that the vR of the subject image can be observed without blocking the light flux emitted from the pentagonal roof prism 4, in other words, the viewfinder field light flux.

When a shutter release operation is performed to take a photograph, the opening release arm 10 is rotated clockwise by a mechanism (not shown). Then, the locking of the claw portions 12a and 13a that are locked by the locking claw 10a is simultaneously released, and the drive pin 12b is driven to be suppressed by the spring force of the drive spring 17, so that the opening slit main arm 1
2 rotates counterclockwise. Along with this, pin 1
2c presses the end of the hole 13b, thereby rotating the entire opening cover sub-arm 13 in the counterclockwise direction.

Open slit main arm 12 made in this way
．． A force is added due to the counterclockwise rotation of the opening cover sub-arm 13 and the clockwise rotation of the opening cover main arm 15 and the opening slit sub-arm 16 due to the spring force of the drive spring 19 being applied to the drive pin 15a. Possibly the first to third blades 20.21
．． 22 are moved upward while maintaining parallel state to each other, the exposure opening 2a is exposed, and when the operation of the front curtain portion 6a is completed, the first to third blades 20, 21 .
22 are stacked in the storage position to cover the notch 2b.

After that, when the rear curtain section 6b is driven, the above-mentioned front curtain section 6a
In contrast to the case in which the first to third blades 20'
, 21' and 22' cover the exposure opening 2a as shown in FIG. 4, and the exposure is completed.

Note that if the closing release arm 10' releases the restraint on the rear curtain part 6b from the time when the front curtain starts traveling by the opening release arm 10 and before the exposure aperture 2a is fully opened, exposure with a predetermined slit width can be provided. Of course.

Then, at the same time as the exposure operation performed by the leading curtain part 6a and the trailing curtain part 6b is completed, a mechanism (not shown) opens the slit main arm 12,
Opening cover sub arm 13, opening cover main arm 1
5. Open slit sub-arm 16 etc. are connected to shaft 11 and shaft 1
4 in a clockwise direction, and the front curtain portion 6a is changed from the state shown in FIG. 4 to the state shown in FIG. 2, that is, the shutter is charged (shutter set).

Also, in the rear curtain section 6b, the first to third blades 20', 21 are placed below the exposure opening 2a as shown in FIG.
', 22' are stored in a stacked state.

Now, the notch 2b is covered by the first to third blades 20.degree. 21.22 when the leading curtain section 6a completes its travel, and remains covered until the shutter charging is completed. , this duration is the winding time of one frame on so-called motor drive winding, and is usually a fraction of the winding time.
Since it takes only a few seconds, it will not interfere with the next shooting.

According to the embodiment configured and operated as described above, the optical axis of the finder optical system can be brought much closer to the optical axis of the photographing lens optical system compared to a conventional camera equipped with a vertically running focal plane shutter. Since the finder optical system can be installed at a lower position, the overall height of the camera can be significantly reduced.

Moreover, since this embodiment does not use any special members or complicated configuration, there is no cost increase compared to the conventional one, and furthermore, there is no risk of impairing the function as a finder.

Rather, when exposure is applied to the exposure aperture 2a, the field of view light flux of the finder optical system is blocked by the first to third blades 20, 21, 22, so the eyepiece lens 5
There is also the advantage that reverse incident light from the side is blocked.

Note that the vertically running focal plane shutter camera according to the present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the gist of the present invention.

For example, the divided curtains constituting each of the leading curtain section 6a and the trailing curtain section 6b are composed of three blades: a first rail and a third blade 20° 21.22, or 20', 21', and 22'.
The structure is not limited to this, and may be a two-sheet structure, a four-sheet structure, or more.

Furthermore, the number of arms for driving these divided curtains is completely arbitrary.

Furthermore, it goes without saying that the energy for driving the front curtain section 6a and the rear curtain section 6b may be not only the one using a spring force but also the electric energy of a motor or a solenoid.

Further, the structure of the finder optical system is not limited to a single-lens reflex type using a pentagonal roof prism, but may be a finder generally used in a lens shutter camera.

Furthermore, as shown in FIG. 1, not only the structure in which the rear part of the pentagonal roof prism 4 and the front part of the eyepiece lens 5 is covered by the front curtain part 6a, but also the structure in which the rear part of the eyepiece lens 5 is covered with the front curtain part 6a. good.

〔Effect of the invention〕

As is clear from the above explanation, according to the camera equipped with the vertically running focal plane shutter according to the present invention, by bringing the photographing optical axis and the viewfinder optical axis closer together, the height of the camera can be significantly reduced, resulting in a significantly smaller size. It is possible to provide a camera equipped with a vertically running focal plane shutter, which is designed to be more compact, and is particularly effective when a bulky pentagonal roof prism is used.

Also, when the time is not normal, that is, when the shutter is operating,
Since the finder optical path of the finder optical system is blocked, harmful reverse incident light from behind the finder can be effectively blocked.

Further, when the shutter is not charged for some reason (for example, when the power supply battery is exhausted), the finder is blocked by the front curtain and is dark, so that an abnormal state can be reliably detected.

[Brief explanation of the drawing]

FIG. 1 is a block diagram conceptually showing an embodiment of the present invention, and FIGS. 2 to 4 show details of the shutter section shown in FIG. 1. Of these, FIG. is a plan view when shutter charging is completed. FIG. 3 is a plan view when the leading curtain has completed traveling, and FIG. 4 is a plan view when the trailing curtain has completed traveling. 1...Photographing lens, 2...Shutter base plate, 2a...Exposure aperture, 2b...Notch, 3...Movable mirror , 4...Pentagonal roof prism. 5...Eyepiece. 6a...first curtain, 6b...
・Second curtain. 10...Open release arm, 10'...
... Closed release arm, 12... Open slit main arm. 13... Opening cover sub arm, 15...
...Opening cover main arm, 16...Opening slit sub-arm, 20.20'...First blade, 21.21'...Second blade, 2
2.22'...Third blade.

Claims (1)

[Claims] (1) In a camera equipped with a vertically running focal plane shutter, the front curtain is placed in a position covering the exposure aperture of the film, and the rear curtain is placed in a lower storage position retracted from the exposure aperture area. and when the shutter is operated, the front curtain is retracted from the exposure aperture area to expose the exposure aperture and is stored above the exposure aperture, and a delay time corresponding to a required shutter speed has elapsed. A vertically running focal plane shutter is driven and controlled so that the rear curtain later covers the exposure aperture, and a finder optical system is disposed near the top of the exposure aperture, and the front curtain covers the exposure aperture. When the front curtain is retracted from the aperture to expose the exposure aperture and is driven to a retracted position above the exposure aperture, at least a portion of the front curtain enters the finder optical path area of the finder optical system and the finder light flux A camera equipped with a vertically running focal plane shutter, characterized in that the camera is configured to shield at least a portion of the shutter.