JP3165303B2 - Camera exposure screen switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure screen switching apparatus for a camera, and more particularly to an exposure screen switching apparatus in which a light shielding plate for defining an exposure screen is movably provided in a dark box.

[0002]

2. Description of the Related Art Recently, the horizontal side of a print is two times longer than the vertical side.
A panoramic camera for creating a wide panoramic print by changing the ratio more than twice as long has been provided. In this panoramic camera, for example, Japanese Patent Application No.
As proposed in Japanese Patent No. 153710, there is a method in which an exposure screen is switched between a full size and a panorama size even during the shooting of one film.

The exposure screen switching mechanism according to the above-mentioned application has a structure in which a pair of light-shielding plates are provided up and down inside a dark box so that the light-shielding plates are retracted from a photographing optical path in a falling state. 24mm x 36mm
Exposure is performed in full size (aspect ratio 1.5),
In the upright state, the light-shielding plate is in a panoramic position in which the light-shielding plate enters the shooting path, so that exposure is performed with a panorama size of 13 mm × 36 mm (aspect ratio 2.8).
Then, the pair of light-shielding plates is subjected to matte painting on the surface facing the shooting optical axis or pasting flocking paper, so that the range where the subject light passes in the dark box at the panorama position is narrowed The generated internal reflection is prevented.

In the background of the present lab industry, a photographic film in which a full-size frame and a panorama-size frame are mixed in a single film (hereinafter, referred to as a "film") is provided as a background of providing a large number of such cameras which can be switched midway. The mixed film is referred to as a "combined film.") It is distinguished from a photo film consisting of only full-size frames, and each frame size of the mixed film is automatically detected and a verification is performed to mark the print type. This is because a photographic print system has been established in which full-size frames and panorama-size frames are separately and efficiently printed without changing the print magnification or the size of the mask.

Therefore, an inexpensive film unit with a lens (hereinafter referred to as a "film unit") proposed in Japanese Patent Publication No. 2-32615 or the like has a built-in exposure screen switching mechanism, and a single unit. It has been desired that the exposure screen can be switched between the full size and the panorama size during the filming so that the filming can be performed.

[0006]

However, in a film unit with a lens in which a film is pre-loaded at the time of manufacture and which is collected at a developing laboratory without taking out the film after use, the cost must be lower than that of an ordinary camera. No. Therefore, in order to prevent internal reflection, a matte coating is applied to the surfaces of the pair of light-shielding plates, or if flocked paper is attached, additional processing is required after molding the light-shielding plates. This also increases costs.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide an exposure screen switching apparatus having a light shielding plate for preventing internal reflection at a panoramic position at a low cost. And

[0008]

According to a first aspect of the present invention, there is provided an apparatus for switching an exposure screen of a camera, comprising the steps of:
Removably attached to the body with an exposure frame, front
There is provided an opening for taking in the photographing light,
Shooting light incident from the opening by being coupled to the main body
A dark room to guide the film to the exposure frame for film exposure
A dark box; a shaft detachably mounted in the dark box
Part is provided, and by rotating around the shaft part
Approaching the exposure frame on the surface provided opposite the shooting optical path
When changing the screen size in the width direction of the photo film at the edge
In addition, a pair of the surfaces provided with irregularities for preventing inner surface reflection.
And a light shielding plate. Claim 2
The camera's exposure screen switching device
Holding a shadow lens and a shutter blade for opening and closing the opening;
It is a thing.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Film unit 2 with lens shown in FIG.
(Hereinafter, referred to as a "film unit"), by sliding the operation knob 3 for switching the screen size, the photographing can be performed by selecting the screen size of the film to either the full size or the panorama size. . The film unit 2 has a configuration in which a unit main body is wrapped in an outer case 4. The outer case 4 includes a photographing lens 5, a shutter button 6, an operation knob 3, a strobe switch 7, a winding knob 8, a finder 9, Charge completion lamp confirmation window 1
0, an opening for exposing the number-of-photographs display window 11, the strobe light emission window 12, and the like to the outside are provided.

As shown in FIGS. 3, 4 and 5, the unit main body has a rear cover 15 on the back of the main body 14 and a strobe unit 16 and a mechanical unit 17 on the front in a detachable manner. A front cover unit 18 is detachably attached so as to cover the upper, front, and both side surfaces. The mechanical unit 17 includes an exposure screen switching mechanism 19 and an exposure applying mechanism 20 including the photographing lens 5.

An exposure frame 21 is integrally formed on the optical axis 5a of the main body base 14, and a patrone chamber 22 and a film roll chamber 23 are integrally formed on both sides of the exposure frame 21. Patrone room 22 and film roll room 23
International Standards (ISO: 1007-19)
The film 24 with a 135-type patrone specified in (1979 version) is loaded, and is housed in a light-tight manner with the rear cover 15.

The exposure frame 21 is formed to have a size slightly larger than the full size, and has a curved shape so as to be convex to the rear side in the film feeding direction together with the film supporting surface 25 provided on the rear side. It has become. The rear cover 15 facing the film support surface 25 is formed with a film regulating surface 26 that is curved in the same manner as the film support surface 25. The mechanical unit 17 is removably attached to the front surface of the exposure frame 21 by nail coupling or the like.

The strobe unit 16 is provided with a strobe light emitting section 27, a battery 28, an X contact 29, and the like.
By pressing the elastic flash switch 7 integrally formed on the front cover 34, the circuit of the flash board 16a is closed via the contact plate 30, and the main capacitor 31 is charged. When the charging of the main capacitor 31 is completed, the charging completion lamp 32 blinks, and when the X contact 29 is turned on in conjunction with the operation of the shutter blade, a trigger signal is transmitted. When this trigger signal is obtained, strobe light is emitted from the strobe light emitting unit 27 through the strobe light emitting window 12.

The mechanical unit 17 has a configuration in which an exposure screen switching mechanism 19, an exposure applying mechanism 20, and the like are incorporated in a dark box 50 for guiding only the subject light transmitted through the photographing lens 5 to the exposure frame 21. On the upper right side of the dark box 50, a concave holding frame 71 is integrally formed. This holding frame 71
A detachable inverted Galilean finder lens including an objective lens 72 and an eyepiece 73 (see FIG. 6) is detachably inserted into the finder lens, and is pressed by a top plate 74 from above. These finder lenses are arranged between the objective window 37 of the front cover 34 and the eyepiece window 75 of the rear cover 15. Note that the exposure applying mechanism 20 is the same as the mechanism described in Japanese Patent Publication No. 2-32615, and a detailed description thereof will be omitted.

The front cover unit 18 includes an operation plate 35,
It comprises a cover plate 36 and a front cover 34 in which these are detachably assembled. On the front cover 34, in addition to the finder objective window 37 and the flash emission window 12, the shutter button 6 and the like are integrally formed. On the front surface of the finder objective window 37, an operation plate 35 is incorporated so as to be slidable along the film feeding direction. The operation plate 35 is integrally provided with a panoramic visual field frame 38 and the operation knob 3. The panoramic field frame 38 is formed to have a size that defines the field of view of the finder 9 with the same aspect ratio as the panoramic size. Further, the cover plate 36 is integrally provided with a full-size field frame 40 defining the same aspect ratio as the full size on the finder optical axis 39 and a long hole opening 41 for movably exposing the operation knob 3 to the outside. It is provided in.

The operation plate 35 is configured such that the operation knob 3 is provided with an elongated hole opening 41.
The slide operation within the panoramic view frame 3
8 is slidably mounted between a panoramic photographing position located on the finder optical axis 39 and a normal photographing position retracted from the panoramic photographing position. At these positions, the notches 42 and 43 provided at the lower portions on both sides are click-coupled with the elastic click claws 44 and 45 provided integrally with the front cover 34. The operation plate 35 is integrally provided with a cam 46 for linking an exposure screen switching mechanism 19 to be described later in association with the movement to these positions. In order to reduce the amount of movement of the operation plate 35, the operation plate 3
The edge 47 at one end of the reference numeral 5 has a cross-sectional shape cut out so as not to block the viewfinder visual field range at the full size position.

FIG. 6 shows a main part of the exposure screen switching mechanism 19. The exposure screen switching mechanism 19 is roughly divided into the intermediate lever 8.
0, torsion spring 81, crank lever 82, spring 95,
And upper and lower light shielding plates 83 and 84. The intermediate lever 80 is provided rotatably about a shaft 86 implanted on the upper surface of the top plate 74. This intermediate lever 80
The torsion spring 8 includes a projection 80a that slides on the cam 46 of the operation plate 35 and a lower projection 80b that are integrally formed.
1, the projection 80a is urged in the direction in which it comes into contact with the cam 46 (clockwise direction shown in the figure).

The crank lever 82 has a pin 82a at one end.
However, a bearing 82b is integrally provided at the other end. When the operation plate 35 is moved toward the panoramic photographing position, a downwardly projecting piece 80b hits the pin 82a. The bearing portion 82 b pivotally supports the upper light shielding plate 83 via a bearing opening 89 provided in the dark box 50, and the upper light shielding plate 83 and the crank lever 82 are integrally connected by a press-fit pin 85.

The lower part of the dark box 50 has a curved shape along the contour of the battery 28. The dark box 50 has a front surface and a rear surface along the optical axis 5a for guiding the subject light incident from the photographing lens 5 to the exposure frame 21. , An opening 87 for passing the subject light,
88 are provided. The dark box 50 has the optical axis 5
The bearing opening 89 and the bearing holes 90 to 92, which are through holes, are integrally formed on both side surfaces sandwiching a. The bearing opening 89 and the bearing hole 90 are formed in the upper light shielding plate 83, the bearing hole 91, and the bearing hole 91, respectively. Reference numeral 92 indicates the center of rotation of the lower light shielding plate 84.

On the outside of the dark box 50 in which the bearing holes 90 to 92 are formed, cylindrical projections 90a, 91a, 92a (see FIG. 3) are integrally formed so as to surround the bearing holes 90 to 92. Have been. Tube projections 90a, 91
Reference numerals a and 92a reliably block extraneous light that enters the interior of the dark box 50 from gaps between the bearing holes 90 to 92 and the shaft portions 83b, 84c and 84d of the upper and lower light shielding plates 83 and 84, which will be described in detail later. . Dark box 5 further provided with bearing holes 90 to 92
0, a pair of stoppers 93, 9 for positioning the upper and lower light shielding plates 83, 84 at the panoramic position.
4 are provided integrally.

The upper light shielding plate 83 is provided with shaft portions 8 on both front sides.
3a and 83b are provided integrally, and the rear edge 83c has the same curved shape as the film support surface 25. Notches are provided between the shaft portions 83a and 83b, and the shaft portions 83a and 83b are elastically deformed to form the bearing holes 8a and 83b.
9, 90 snap-fit. Further, between the notch and the edge 83c, a shielding wall 83d for blocking extra light incident from the notch is integrally formed.

The upper light shielding plate 83 has a connecting pin 83e for transmitting the rotation of the crank lever 82 to the lower light shielding plate 84.
Is provided. The projecting piece 84a of the lower light shielding plate 84 abuts on the connecting pin 83e. Then, the projecting piece 84a is brought into contact with the connecting pin 83e by the spring 95,
That is, the upper and lower light shielding plates 83 and 84 are biased toward the full size position defining the full size in the exposure frame 21. The projecting piece 84a is provided with a slit 84b for absorbing the pressure received from the connecting pin 83e. Further, inside the dark box 50, a light-shielding frame 96 for preventing flare during normal photographing is attached.

The lower light shielding plate 84 is provided with shaft portions 84c and 84d on both sides on the front end side. Shaft 84
Notches d and 84d are respectively formed inside these, and are elastically deformed and snap-coupled to bearing holes 91 and 92. Then, the lower light shielding plate 84 is
In conjunction with the rotation of, the camera rotates between a panoramic position (see FIG. 9) protruding into the photographing optical path and a full-size position (see FIG. 10) retracted downward from this.

The lower light shielding plate 84 has a curved shape along the bottom surface of the dark box 50 in order to reliably prevent flare due to internal reflection. The lower light shielding plate 84 also has a curved shape along this curved shape. The lower light-shielding plate 84 has a cross-sectional shape in which the edge 84e is bent upward in an L-shape, and has a shape in which the inner side is deepened to reduce flare due to internal reflection. The edge 84e has the same curved shape as the film support surface 25 along the horizontal direction. Further, a pair of bag-shaped blocking walls 84f are integrally formed with the shaft portions 84c and 84d, respectively, to block extraneous light entering the film surface from the cutout portions. In FIG. 6, in order to prevent the drawing from being complicated,
The exposure applying mechanism 20 is omitted.

More specifically, as shown in FIG. 7, the surface of the upper light shielding plate 83 facing the optical axis 5a has a plurality of sawtooth cross sections along the film feeding direction in order to prevent internal reflection occurring at the panoramic position. A light-shielding groove 83f is formed integrally. Further, the shielding wall 83d is provided with the upper light shielding plate 8 from the notch.
3 is bent away from the optical axis 5a in order to prevent light from sneaking into the back side, and has a shape in which the inner pocket is deepened to reduce flare due to internal reflection. On the inner surface facing the optical axis 5a, a grain 83g having a surface roughness of 10 μm or more is provided.
Is given. The grain 83g is not applied by secondary processing, but is applied at the same time when the upper light shielding plate 83 is formed. The surface roughness of the grain 83g is preferably about 30 μm.

In more detail, as shown in FIG.
A plurality of sawtooth-shaped light-shielding grooves 84g are formed integrally on the surface of the lower light-shielding plate 84 facing the position "a" along the film feeding direction in order to prevent internal reflection at the panorama position. Further, between the shielding groove 84g and the edge 84e, an inner surface opposing the optical axis 5a of the lower light shielding plate 84 opposing the optical axis 5a is provided with a grain 84h having a surface roughness of 10 μm or more. The embossing 84h is not performed by secondary processing, but is performed simultaneously when the lower light shielding plate 84 is formed.
Furthermore, in order to prevent light from sneaking into the back side of the lower light shielding plate 84 from the notch, a blocking piece 84i is formed integrally with the edge opposite to the edge 84e along the film feeding direction. The surface roughness of the grain 84h is as follows.
About 30 μm is preferable.

Next, the operation of the above embodiment will be described. The film unit 2 is provided in a form stored in a moisture-proof bag. When the film unit 2 is taken out of the moisture-proof bag, as shown in FIG. 9, the upper and lower light shielding plates 83 and 84 abut against the stoppers 93 and 94. Panorama position. Therefore, when looking directly through the eyepiece window 75, the panoramic field frame 38 of the operation plate 35 limits the finder field of view to a field of view similar to the panorama size aspect ratio.

In the case of photographing, first, the film winding operation is performed by turning the winding knob 8. The film 24a is transported in conjunction with this film winding operation, and
When the transfer of the frame is completed, the film winding stop mechanism is operated, the operation of the winding knob 8 is locked, and the shutter mechanism is charged.

After completion of the winding operation, the photographer moves the eyepiece window 7
While performing peep framing from 5, the strobe switch 7 is pressed. By this pressing operation, the power of the battery 28 is supplied to the circuit of the strobe unit 16, and the high voltage is charged in the main capacitor 31. Main capacitor 3
When the charging of 1 is completed, the charging lamp 32 blinks. After confirming this blinking, shooting is performed.

The photographing is performed by pressing the shutter button 6. With this operation, the shutter mechanism operates to open and close the shutter blades. During this opening and closing, the shutter blade turns on the X contact 29. The strobe light is emitted from the strobe light emitting unit 27 when the X contact 29 is turned on.

The subject light illuminated by the strobe light passes through the photographing lens 5 and is blocked by upper and lower light blocking plates 83 and 84.
The film 24a is exposed on a panoramic-size screen. At this time, as shown in FIG. 1, the upper and lower light shielding plates 83 and 84 facing the optical axis 5a are provided with light shielding grooves 83f and 84g and embosses 83g and 84h. The dotted lines indicated by reference numerals A and B in the figure) are disturbed, and extra light incident on the film 24a decreases.
Also, light that goes around the upper and lower portions of the upper and lower light shielding plates 83 and 84 inside the dark box 50 (for example, the dotted line indicated by the symbol C in the same figure)
Can be shielded by the shielding wall 83d and the light shielding piece 84i.

When photographing is performed on a full-size exposure screen, the operation knob 3 is slid rightward in FIG. 6 to connect the notch 43 of the operation plate 35 with the click claw 45 of the front cover 34. Cancel. When these couplings are released, the torsion spring 81 urges the intermediate lever 80 clockwise, so that the operation plate 35 smoothly moves rightward. When the notch 42 engages with the click claw 44, the finder optical axis 39 is set.
, The panoramic size field frame 38 is retracted.
At this time, the photographer is given a click feeling to recognize that the size of the exposure screen has been switched.

The movement of the operation plate 35 causes the intermediate lever 80 to move.
Is rotated clockwise about the shaft 86 by the bias of the spring 81. In conjunction with this rotation, the crank lever 82 rotates counterclockwise about the bearing 82b. In conjunction with this rotation, the upper light shielding plate 83 rotates counterclockwise around the shafts 83a and 83b, and the lower light shielding plate 84 is urged by the spring 95.
Also rotates clockwise about the shafts 84c and 84d. As a result, the upper and lower light shielding plates 83 and 84 are in a state where the screen size is defined to the full size as shown in FIG. In this state, the upper and lower light shielding plates 83 and 84 are
Abuts the inner wall to accurately determine the full-size screen.

Thereafter, after performing the film winding operation in the same manner as described above, framing is performed by looking through the eyepiece window 75. At this time, the finder field of view is limited to a field of view corresponding to the full size in the full size field frame 40. Exposure is performed by pressing the shutter button 6 in the same manner as described above.

As described above, the photographing is performed while the operation knob 3 is selectively operated to one of the full size photographing position and the panoramic photographing position. Then, when the photographing of all the frames is completed, the film unit 2 is submitted to the developing laboratory as it is. At the developing station, the cartridge 24b containing the exposed film 24a is taken out. At this time, if a display indicating that the film is a mixed film is given to the patrone 24b, the work at the developing laboratory becomes simple.

The patrone 24b taken out is developed by a film processor and then inspected for frame size and the like by a notch / puncher. In this test, a notch is applied to a full size frame to distinguish it from a panorama size frame. At this time, the panorama size frame is about 13 ×
Since the rectangular size is 36 mm, the process is performed while detecting the frame size. Then, the verified negative film is set on the scanner, where the image of the notched frame, that is, the image of only the full size frame is read,
The correction amount of each frame for obtaining an appropriate exposure amount at the time of printing is calculated. The correction data is written on the LSI card in association with the frame number. When the work on the scanner is completed, the negative film together with the LSI card is set in the printer processor. Here, print processing is continuously performed on only full-size frames, and a print photograph of 89 × 127 mm is obtained.

Next, the negative film is set again in the scanner together with the LSI card, and only a panorama-sized frame is read to calculate a correction amount for obtaining an appropriate exposure amount. Then, the negative film together with the LSI card is set in the printer processor, and only the panorama size frames are continuously printed. This allows 89 ×
A print photograph having a size of 254 mm is obtained.
At this time, the print magnification of the printer and the sizes of the printing paper and the paper mask are changed. The print magnification from a full-size frame to photographic paper is about 3.5 times, and the print magnification from a panorama-size frame to photographic paper is about 7 times. After performing the printing process as described above, the print photo and the negative film are returned to the user. Then, the empty film unit 2 is collected at the factory and recycled.

[0038]

As described above in detail, according to the present invention, in order to prevent the internal reflection, the unevenness is integrally formed on the surface of the light shielding plate for shielding the photographing optical path. As a result, the number of components and the number of steps can be reduced as compared with those described in the related art, so that the cost of the exposure screen switching device can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a film unit with a lens.

FIG. 2 is a perspective view showing an appearance of a film unit with a lens.

FIG. 3 is an exploded perspective view showing a main part of the film unit with a lens.

FIG. 4 is an exploded perspective view of the mechanical unit.

FIG. 5 is an exploded perspective view showing a front cover unit.

FIG. 6 is an exploded perspective view showing an exposure screen switching mechanism.

FIG. 7 is a perspective view showing an upper light shielding plate.

FIG. 8 is a perspective view showing a lower light shielding plate.

FIG. 9 is an explanatory diagram showing a state of a panoramic position of upper and lower light shielding plates.

FIG. 10 is an explanatory diagram showing a state of the upper and lower light shielding plates at a full size position.

[Explanation of symbols]

 17 Mechanical base 50 Dark box 83 Upper light shield 84 Lower light shield 83f, 84g Groove 83g, 84h Surface

Claims (2)

(57) [Claims] 1. A removably mounted main body having an exposure frame.
An opening is provided on the front for taking in the shooting light.
From the opening by being connected to the main body
It guides the incoming photographic light to the exposure frame for film exposure.
A dark box for forming a dark room, and a shaft portion detachably mounted in the dark box.
By rotating around the shaft, the optical path against
The edge of the surface facing the exposure frame close to the exposure frame
Change the screen size in the width direction of the
And a pair of light-shielding plates provided with irregularities for preventing internal reflection
Camera exposure screen switching apparatus characterized by comprising. 2. A photographic lens and a front lens are provided in front of the opening.
2. An exposure screen switching device for a camera according to claim 1, wherein a shutter blade for opening and closing said opening is held .