JPH02262632A - Bifocal switching camera - Google Patents

Abstract

PURPOSE:To securely prevent a movable mirror from being stained and damaged and to enable excellent photography for a long period by providing a movable mirror switching means which switches the movable mirror to the position where its reflecting surface moves back away from in front of an opening for exposure associatively with rewinding starting operation for a film. CONSTITUTION:If the movable mirror 30 is in a wide-angle state, i.e. at a 1st position when the film begins to be rewound, the movable mirror is switched automatically into the wide-angle state. Consequently, the movable mirror 30 is held at the 2nd position where its reflecting surface 30a moves back away from in front of the opening 16 for exposure during the rewinding operation for the film. Therefore, even if dust or dirt sticking in the film or an emulsifying agent peeled off the film enters a camera main body 10 through the opening 16 for exposure during the rewinding operation for the film, they are securely prevented from sticking on the reflecting surface 30a of the movable mirror 30. Consequently, the movable mirror is prevented from being stained and damaged to enable excellent photography for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION (Industrial Field of Application) The present invention relates to a bifocal switching camera equipped with a telephoto lens and a wide-angle lens.

(Prior Art) In recent years, bifocal switching cameras have been provided in which a telephoto lens and a wide-angle lens are installed in the main body of the camera, and these lenses are used by switching between them. usually,
This type of camera has a fixed mirror located on the optical axis of a telephoto lens, an exposure aperture located on the optical axis of a wide-angle lens, and a movable mirror. and,
Switching of the photographic lens is performed by rotating the movable mirror from a telephoto position located on the optical axis of the wide-angle photographing lens to a wide-angle position located away from the optical axis of the wide-angle photographing lens.

However, in a camera with the above configuration, when the movable mirror is moved to the telephoto position, that is, when the reflective surface of the movable mirror is facing the exposure aperture, the camera body must be opened to remove or load film. When the back cover of the camera is opened, there is a risk that strings, debris, etc. may enter the camera body through the exposure opening and become attached to the reflective surface of the movable mirror. In this way, there is dust on the reflective surface of the movable mirror.
If a lump or the like adheres to the lens, it becomes impossible to take good photographs.

Therefore, for example, in the bifocal switching camera disclosed in U.S. Pat. No. 4,772,903, the
The mirror is configured to move the movable mirror to a wide-angle position in response to the opening operation of the IMH, and to prevent dust, chips, etc. from adhering to the reflective surface of the movable mirror.

(Problem to be solved by the invention) However, the above US Patent C;
Focus switching cameras have the following problems:

In other words, if you rewind the film while the rotating mirror has moved to the telephoto position, dust, flakes, etc. on the film may enter the camera body through the exposure opening, causing the movable mirror to move to the telephoto position. It will stick to reflective surfaces. Furthermore, during film rewinding, the film slides on the film guide at high speed. Therefore, the emulsifier coated on the film is peeled off from the film, and the peeled emulsifier passes through the exposure opening and adheres to the reflective surface of the movable mirror. Therefore, it becomes difficult to take good pictures.

Furthermore, the leading end of the film is usually curled inward. Therefore, when the leading edge of the film passes over the exposure opening at the end of the rewinding operation, the leading edge of the film may protrude into the camera body through the exposure opening. Therefore, when the movable mirror is at the telephoto position, there is a risk that the reflective surface of the movable mirror may be damaged by the leading end of the film protruding into the camera body. If the reflective surface of the movable mirror is scratched, it will be difficult to take good pictures.

The present invention has been made in view of the above points, and its purpose is to provide a bifocal switching camera that can reliably prevent dirt and damage to the movable mirror and that can take good pictures over a long period of time. There is a particular thing.

[Structure of the Invention] (Means and Effects for Solving the Problems) In order to achieve the above object, according to the bifocal switching camera of the present invention,
A movable mirror switching means is provided for switching the movable mirror to a second position, that is, a position where the reflective surface is retracted from the front of the exposure opening in conjunction with the start operation of rewinding the film.

According to the above configuration, during the film rewinding operation, the movable mirror is maintained with its reflective surface retracted from the front of the exposure opening. Therefore, staining and damage to the reflective surface of the movable mirror during the film rewinding operation is prevented.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 8 show a bifocal switching camera according to a first embodiment of the present invention. As shown in FIG. 1D, this camera includes a camera body 10 having a back cover 12 that can be opened and closed. By opening the back cover 12, film can be loaded into and removed from the camera body 10. When loaded into the camera body 10, the film 14 is positioned so as to cover one end side of an exposure opening 16 formed in the camera body.

Inside the camera body 10, there is a first photographing optical system 18 that has a relatively long focal length and is used for telephoto photography, and a second photographic optical system that has a relatively short focal length and is used for wide-angle photography. 20 are provided. The second photographing optical system 20 is arranged so that its optical axis passes through the center of the exposure aperture 16 and is orthogonal to the film 14. Further, the first photographing optical system 18 is provided above the second photographing optical system 20 so that its optical axes are parallel to each other. These photographic optical systems 18 and 20 are supported by a support frame 22 so as to be movable along the optical axis direction. Transparent glass windows 24.25 are provided in front of the first and second photographing optical systems 18.20, respectively. Further, a shutter 21 is provided inside the first photographing optical system 18 and behind the second photographing optical system 18.

Behind the first photographing optical system 18 in the camera body 10,
A fixed mirror 26 is provided and is positioned obliquely on the optical axis of the first photographing optical system. Furthermore, a movable mirror 30 fixed on a support plate 28 is disposed within the camera body 10. One end of the support plate 28 is rotatably attached to the camera body 10. Thereby, the movable mirror 30 is rotatable together with the support plate 28 between a first position shown by a solid line in FIG. 1 and a second position shown by a two-dot chain line.

In the first position, the movable mirror 30 is positioned obliquely on the optical axis of the second photographing optical system 20, and its reflective surface 30a faces the exposure aperture 16 and the fixed mirror 26. Therefore, the movable mirror 30 guides the optical image that enters the camera body 10 through the first photographing optical system 18 and is reflected by the fixed mirror 26 onto the film 14 through the exposure aperture 16.

As a result, telephoto shooting using the first photographing optical system 18 becomes possible. In the second position, the movable mirror 30
The reflecting surface 30a moves away from the front of the exposure aperture 16 and blocks the optical path of the optical image reflected by the fixed mirror 26.

Therefore, instead of the optical image that entered through the first imaging optical system 18, the optical image that entered through the second imaging optical system 20 is guided onto the film 14 through the exposure aperture 16. As a result, wide-angle photography using the second photography optical system becomes possible.

In this way, by switching the movable mirror 30 to the first or second position, telephoto shooting and wide-angle shooting can be selectively performed.

As shown in FIG. 2, the bifocal switching camera has a finder mechanism 3 that is switched in conjunction with the rotation of a movable mirror 30.
2. The viewfinder mechanism 32 has first and second lens groups 36.37 each held by a frame 34.35. The first and second frames 34.35 are connected to the second frame by a guide mechanism (not shown).
In the figure, it is guided so as to be movable in the horizontal and vertical directions. And this finder machine fM
32 and the movable mirror 30 are switched in conjunction with each other by a switching mechanism 38.

The switching mechanism 38 includes a rotating shaft 40 rotatably supported by the camera body 10. rotating shaft 40
is connected to the support plate 28 of the movable mirror 30, and can rotate integrally with the support plate. A substantially V-shaped cam 42 having a pair of legs 42a142b is fixed to the rotating shaft 40, and is rotatable together with the rotating shaft. Further, a first rotating arm 44 is fixed to the rotating shaft 40, and a second rotating arm 46 having a rotation center (not shown) is engaged with the rotating shaft 40. It is rotated in a predetermined direction according to the rotation. Also, the first and second rotating arms 44.4
The tips of 6 engage the first and second frames 34, 35 of the finder mechanism 32, respectively.

The switching mechanism 38 includes a switching motor 48 and a drive gear 52 that is rotationally driven by the motor via a gear train 50. The drive gear 52 is provided below the cam 42 and has a suppression pin 54 that is provided so as to be able to come into contact with the legs 42a and 42b of the cam. For example, in FIG. 2, when the drive gear 52 is rotated in the direction of the arrow, the pressure bottle 54
The cams 42 are rotated by predetermined angles in mutually different directions.

FIG. 2 shows a state in which the movable mirror 30 and the finder mechanism 32 are set in a telephoto state (T state). That is, the pressing pin 54 of the drive gear 52 is in contact with the leg portion 42a of the cam 42, and the cam is rotated by a predetermined angle in the direction of arrow B. Thereby, the rotating shaft 40
The support plate 38 and the movable mirror 30 rotate together with the movable mirror, and the movable mirror is located at the first position. Similarly, the first and second frames 34.35 of the finder mechanism 32 have been moved to the positions shown by the first and second pivot arms 44.46. In the telephoto state, only the first lens group 36 of the finder mechanism 32 is used.

From the telephoto state shown in FIG.
When rotated about 180 degrees in the direction, as shown in Figure 3,
The pressing pin 54 presses the leg portion 42b of the cam 42 and rotates the cam in the direction of arrow C by a predetermined angle. At this time, the rotating shaft 40 rotates together with the cam 42, and the movable mirror 30 is rotated together with the support plate 38 to the second position.

Furthermore, in conjunction with the rotation of the rotation shaft 40, the first and second rotation arms 44, 46 rotate in a predetermined direction. As a result, the first lens group 36 of the finder mechanism 32 is moved to the left in FIG.
is moved upward.

Therefore, the movable mirror 30 and finder mechanism 32 are
The wide-angle fiCW shape shown! @).

In the wide-angle state, the first and second lens groups 36.3
7 have their optical axes aligned and are used in combination with each other.

When the drive gear 52 is rotated approximately 180 degrees in the direction of arrow A from the wide-angle state, the leg portion 42 of the cam 42 is
g is pressed, and the cam is rotated by a predetermined angle in the direction of arrow B. Thereby, the movable mirror 30 and the finder mechanism 3
2 is again switched to the telephoto state shown in FIG.

As shown in FIGS. 4 and 5, a position detection switch 56 is provided above the cam 42 to detect the state, that is, the position, of the finder mechanism 32 and the movable mirror 30. The position detection switch 56 has a pair of first terminals 5
8a and a pair of second terminals 58b, these terminals are attached to the support member 60 and positioned parallel to each other.

The cam 42 also has a protrusion 62, which is located between the first terminal 58a and the second terminal 58b. Then, when the cam 42 rotates to the position where the movable mirror 30 and the finder mechanism 32 are set to the telephoto state, the protrusion 62
presses one of the first terminals 58a toward the other and
Close the terminals. Further, when the cam 42 rotates to a position where the movable mirror 30 and the finder mechanism 32 are set to a wide-angle state, the protrusion 62 presses one of the second terminals 58b toward the other, thereby closing the second terminal. By detecting opening of the first and second terminals 58a and 58b, the positions of the movable mirror 30 and the finder mechanism 32 can be detected.

FIG. 6 shows the entire structure of the bifocal switching camera in blocks. Bifocal switching camera uses film 14
It has a film transport mechanism 64 for transporting the film for rewinding and winding. The transport motor drive circuit 65 drives the transport motor 67 of the film transport mechanism 64 based on control signals from the CPU 66, that is, winding signals and rewinding signals. Further, the encoder circuit 68 generates a transport pulse corresponding to the film transport amount and inputs it to the CPU 66. The switching motor drive circuit 69 is
The switching motor 48 of the switching mechanism 38 is driven in response to a switching signal from the CPU. In addition, the position detection switch 56
When the first terminal 58a of the CPU 66 is closed, the port PT of the CPU 66 becomes a low level (L), and when the second terminal 58b is closed, the port Pv of the CPU becomes a low level. Further, when the intermediate rewind switch 70 provided on the outer surface of the camera body 10 is closed, the boat PR of the CPU 66 becomes low level. In addition, the switching mechanism 38, the CPU 66,
The switching motor drive circuit 69 constitutes movable mirror switching means for switching the movable mirror 30 to the second position at the start of a film rewinding operation, which will be described later.

Next, the operation of the bifocal camera configured as above will be explained.

Normal switching between the movable mirror 30 and the finder mechanism 32 is performed by pressing a switch (not shown) provided on the outer surface of the camera body 10. When the changeover switch is pressed, the CPU 66 detects the positions of the movable mirror 30 and the fender machine side 32 based on the detection signal from the position detection switch 56, and outputs a changeover signal to the changeover motor drive circuit 69. In response, the switching mechanism 38 switches the movable mirror 30 and finder mechanism 32 from the telephoto state to the wide-angle state or vice versa. Subsequently, the CPU 66 detects the positions of the movable mirror 30 and the finder mechanism 32 again based on the detection signal from the position detection switch 56, and thereby,
The switching operation ends.

The film rewind operation is performed as follows.

FIG. 7 and FIG. 8 show an operation flow and a flowchart at the time of rewinding, respectively.

When the film 14 is used for a predetermined number of frames and the end of the film is detected by a known film end detection means,
The CPU 66 detects the positions of the movable mirror 30 and the finder mechanism 32 based on the detection signal from the position detection switch 56. When the movable mirror 30 and the finder mechanism 32 are in a telephoto state, that is, when the boat PT-
In the case of L, the switching mechanism 38 is driven to switch the movable mirror and finder mechanism to the wide-angle state. Therefore, the movable mirror 30 is switched from the first position to the second position. After that, the CPU 66 again detects the positions of the movable mirror 30 and the finder mechanism 32 based on the detection signal from the position detection switch 56, and after confirming that these are in the wide-angle state, that is, the boat pw-Ll, moves the film. The mechanism 64 is driven to start rewinding the film 140.

When the end of the film 14 is detected, if the movable mirror 30 and finder mechanism 32 are in the wide-angle state,
Rewinding of the film 14 is immediately started without switching these.

On the other hand, when the halfway rewind switch 70 is pressed while the film 14 remains, the CPU 66ζ detects the positions of the movable mirror 30 and the finder mechanism 32 based on the detection signal from the position detection switch 56. Then, when the movable mirror 30 and the finder mechanism 32 are in the telephoto state, the CPU 66 switches them to the wide-angle state and then starts rewinding the film 14, and when the movable mirror and the finder mechanism are in the wide-angle state, starts rewinding the film without switching these.

For example, when opening the back M12 of the camera body 10 to take out or replace the film 14, the movable mirror 30 and finder mechanism 32 are moved to the wide-angle state by a known holding means in conjunction with the opening of the back cover. Retained.

According to the bifocal switching camera configured as above,
If the movable mirror 30 is in the wide-angle state when starting the film rewinding operation, that is, if the movable mirror is in the first position, the movable mirror is automatically switched to the wide-angle state. Therefore, during the film rewinding operation, the movable mirror 30 is held at the second position where its reflective surface 30a is retracted from the front of the exposure opening 16. Therefore, even if dust or flakes adhering to the film or emulsifier peeled off from the film enter the camera body 10 through the exposure opening 16 during the rewinding operation, these particles will be removed from the reflective surface of the movable mirror 30. It is possible to reliably prevent it from adhering to 30a. Further, when the film is finished being rewound, the leading end of the film passes through the exposure opening 16 to the camera body 10.
Even when the film protrudes inward, the leading end of the film can be prevented from coming into contact with the reflective surface 30a of the movable mirror 30, and as a result, damage to the movable mirror can be reliably prevented.

From the above, according to the bifocal switching camera of this embodiment, it is possible to perform good photography over a long period of time.

9 to 12 show a bifocal switching camera according to a second embodiment of the invention. According to the second embodiment, a movable mirror switching mechanism is provided that switches the movable mirror in conjunction with the operation of the film transport mechanism. Note that the same parts as in the first embodiment are given the same reference numerals and detailed explanation thereof will be omitted.

As shown in FIG. 9, the film transport mechanism 64 includes a transport motor 72 and a drive gear 74 rotationally driven by the transport motor. On both sides of the drive gear 74, a rewinding gear 76 and a winding gear 78 are provided spaced apart from each other. One end of a rotating arm 80 is rotatably attached to the pivot of the drive gear 74. Further, a planetary gear 82 is rotatably supported at the intermediate portion of the rotating arm 80, and this am gear meshes with the drive gear 74. Note that the tip portion 80a of the rotating arm 80 is connected to the planetary gear 8.
Extending beyond the periphery of 2.

The planetary gear 82 and the rotating arm 80 are rotated about the axis of the driving gear in response to the rotation of the driving gear 74.

That is, when the drive gear 74 is rotated counterclockwise by the transfer motor 72, the planetary gear 82 rotates as shown in FIG.
rotates counterclockwise together with the rotating arm 80, and moves to the winding position where it meshes with the winding gear 78. Therefore, the driving force of the transfer motor 72 is transmitted to the winding gear 78 via the driving gear 74 and the planetary gear 82, and the film is wound.

Further, when the drive gear 74 is rotated in the direction S by the transfer motor 72, the planetary gear 82 is rotated as shown in FIG.
rotates clockwise together with the rotating arm 80, and moves to the rewinding position where it meshes with the rewinding gear 76. Therefore, the driving force of the transfer motor 72 is transmitted to the rewind gear 76 via the drive gear 74 and the planetary gear 82, and the film is rewound.

On the other hand, one end of an interlocking arm 84 is fixed to the support plate 28 of the movable mirror 30, and this interlocking arm extends from the support plate to the back side of the movable mirror. In particular, the interlocking arm 84 is
It is located on the movement path of the rotating arm 80 of the film transport mechanism 64, and is provided so as to be able to engage with the distal end portion 80a of the rotating arm. Therefore, as shown in FIG.
0 is in the first position, when the a star gear 82 and the rotating arm 80 are rotated from the winding position to the rewinding position, the interlocking arm 84 is pressed by the tip 80a of the rotating arm 80. to switch the rotating mirror 30 from the first position to the second position. While the rotating arm 80 and the planetary gear 82 are located at the rewinding position, the interlocking arm 84 is moved by the rotating arm to the state shown in FIG. 9, that is, the rotating mirror 30 is located at the second position. held in state.

In this way, the interlocking arm 84, the rotating arm 80 and the
! The first star gear 82 is a movable mirror switching mechanism 8 that switches the movable mirror 30 in conjunction with the operation of the film transport mechanism 64.
6. In addition, this movable killer switching mechanism 8
6 constitutes a movable mirror switching means in this invention.

In the second embodiment, the rewinding operation of the film 14 is performed as follows.

That is, when the end of the film is detected by the film end detection means, or when the rewind switch is pressed halfway, the moving motor 72 of the film transport mechanism 64 is driven in reverse, thereby causing the rotating arm 80 and the planetary Gear 82 is rotated from the winding position to the unwinding position. At this time, when the movable mirror 30 is in the first position, the movable mirror is switched to the second position by the movable mirror switching mechanism 86 while the pivot arm 80 and the planetary gear 82 reach the rewind position. After the above switching operation is completed,
The rewinding operation of the film 14 is started. Figure 12 shows
The above-described rewinding operation flow is schematically shown.

Further, as shown in FIG. 10, when rewinding the film 14 with the movable mirror 30 in the second position,
The movable mirror is held in the second position without being switched.

Note that switching of the movable mirror 30 during photographing is performed by the same switching mechanism as in the first embodiment.

Also in the second embodiment configured as described above, when the rewinding operation of the film 14 is started, the movable mirror 30 is automatically moved to the second position, that is, the position where the reflective surface is retracted from the front of the exposure aperture 16. can be switched. Therefore, the same advantages as the first embodiment can be obtained.

Note that this invention is not limited to the embodiments described above, and can be modified in various ways within the scope of this invention. For example, in the above embodiment, the movable mirror and the finder mechanism were configured to be switched by the same motor, but they may be switched by separate drive sources. An actuator or the like may also be used.

[Effects of the Invention] As detailed above, according to the present invention, the movable mirror is moved to the second position in conjunction with the film rewinding start operation, that is, the position where the reflective surface is retracted from the front of the exposure aperture. Since the movable mirror is provided with a movable mirror switching means for switching to the movable mirror, it is possible to provide a bifocal switching camera that prevents dirt and damage to the movable mirror and allows good shooting over a long period of time.

[Brief explanation of drawings]

1 to 8 show a bifocal switching camera according to a first embodiment of the present invention, FIG. 1 is a sectional view of the camera, and FIG. 2 shows a finder mechanism and a switching mechanism of the camera. 3 is a perspective view of the finder mechanism and the switching mechanism in an operating state different from that in FIG. 2; FIGS. 4 and 5 are a side view and a top view showing the arrangement of the position detection switch and the cam; FIG. 6 is a block diagram schematically showing the overall structure of the camera, FIGS. 7 and 8 are operation flows and flow charts for explaining the film rewinding operation of the camera, and FIGS. 9 to 12 are , shows a bifocal switching camera according to a second embodiment of the present invention, FIGS. 9 to 11 are cross-sectional views schematically showing different operating states of the camera, and FIG. 12 is a film roll of the camera. It is an operation flow for explaining a return operation. DESCRIPTION OF SYMBOLS 10... Camera body, 12... Back cover, 14... Film, 16... Exposure aperture, 18... First photographing optical system, 20... Second photographing optical system, 26... Fixed mirror 30... Movable mirror 30a... Reflective surface, 3
8... Switching mechanism, 64... Film transport mechanism, 8
6...Movable mirror switching mechanism. Applicant's representative Patent attorney Atsushi Tsuboi 4 A 6 5 Figure 1, Indication of the case, Japanese Patent Application No. 1-84442, Title of the invention, Bifocal switching camera 3, Person making the amendment, and Relationship Patent applicant (037) Olympus Optical Industry Co., Ltd. 4, Agent address 3-7-2 Shugaseki, Chiyoda-ku, Tokyo 100
Telephone: 03 (502) 31111 (main representative) 4th friend phrase composition 5゜ spontaneous amendment 7, content of amendment (1) "emulsifier" in lines 8 and 9 of page 4 of the specification is changed to "emulsion" I am corrected. (2) "Wide-angle" in line 11 of page 17 is corrected to "telephoto." (3) "Emulsifier" in line 17, line 18 of the same is corrected to "emulsion." (4) "Killer" in line 6 of page 21 is corrected to "mirror."

Claims (1)

[Scope of Claims] A first photographing optical system; a second photographing optical system that is installed alongside the first photographing optical system and has a focal length different from that of the first photographing optical system; a fixed mirror provided on the optical axis of the second photographing optical system; an exposure aperture located on the optical axis of the second photographic optical system; a reflective surface located opposite the exposure aperture; a first position for guiding an optical image reflected by the fixed mirror through the first photographing optical system to the exposure aperture; and a second position for guiding the optical image reflected by the fixed mirror through the first photographing optical system to the exposure aperture; a movable mirror that is movable to a second position where the optical image that has passed through the system is incident on the exposure aperture; and a movable mirror that is movable to the second position in conjunction with an operation to start rewinding the film. A bifocal switching camera characterized by comprising: a movable mirror switching means for switching to a movable mirror;