JPH11174582A - Single lens reflex camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a photographic film from being inadvertently exposed due to a misoperation. SOLUTION: When a power source is turned on and a timer interruption is executed, a shutter checking operation is performed, that is, the mounting state of a lens unit, the identification of a shutter type and the operating state of the shutter, etc., are checked. In the case of checking the shutter, the mirror position is checked. Based on the checked results, a warning is issued in the case the lens unit is not mounted even through the mirror is positioned in a lifting state and a photographing optical path is open.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-lens reflex camera, and more particularly to a single-lens reflex camera which prevents exposure of a photographic film due to an erroneous operation.

[0002]

2. Description of the Related Art A lens shutter type single-lens reflex camera is known as a camera having a large screen size using a brownie film. This single-lens reflex camera includes a camera body, a lens unit with a built-in shutter mounted on the camera body, a film holder for storing a photo film, and a plurality of photographing units such as an AE finder having an automatic exposure function. By appropriately combining these units, the system camera can cope with shooting under various conditions.

[0003] The camera body of the above-mentioned single-lens reflex camera is provided with a mirror which opens a photographic optical path when ascending and closes a photographic optical path when ascending to form a finder optical path. Further, in order to completely close the photographing optical path when the mirror is lowered, the camera body is provided with a light shielding plate which rises and lowers in conjunction with the mirror.

[0004]

In the single-lens reflex camera described above, the photographic film may be exposed due to an erroneous operation of removing the lens unit from the camera body with the mirror moved to the raised position. Further, when the lens unit is removed while the photo film is loaded in the film holder, the mirror may be erroneously moved to the raised position.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to prevent careless exposure of a photographic film due to erroneous operation.

[0006]

In order to solve the above-mentioned problems, a single-lens reflex camera according to the present invention provides a warning when a lens unit is detached from a camera body when a mirror is in a raised position. It was made. Further, when the photographing optical path is blocked after the warning, the shutter release for one frame is prohibited, and the photographic film is fed for one frame. Further, when the taking lens unit is not attached to the camera body, the operation of moving the mirror to the raised position is invalidated.

[0007]

FIG. 2 shows the appearance of a lens shutter type single-lens reflex camera 2 of the present invention. The single-lens reflex camera 2 includes a camera body 3, a film holder 4 attached to the rear side of the camera body 3, a camera body 3
This is a system camera constituted by a combination of a lens unit 5 mounted on the front side of the camera and various photographing units such as an AE finder 6 mounted on the upper part of the camera body 3.

A plurality of lens units 5 having different focal lengths are prepared, and these can be used interchangeably. The AE finder 6 is also detachable from the camera body 3, so that an angle finder or a waist level finder can be mounted according to the purpose of use. This single-lens reflex camera 2 is obtained by adding various functions to an old-type system camera having the same configuration, and is compatible so that a shooting unit such as an old-type lens unit and a film holder can be used. ing.

The camera body 3 has a box shape in which a mirror mechanism, a control circuit and the like are incorporated, and a focus adjustment mechanism 8 for adjusting focus is attached to a lower portion of the camera body 3. As shown in FIG. 3 which is a side view and a cross-sectional view of a main part of the single-lens reflex camera 2, openings 10 and 11 are formed on the front side and the back side of the camera body 3, respectively. A bellows 13 that shields the photographing optical path is mounted between the front opening 10 and the lens board 12 that forms the focus adjustment mechanism 8. The camera body 3
The opening 11 formed on the back side of the
Are installed facing each other.

A lens unit 5 is mounted on the front surface of the lens board 12 and is fixed by a lock lever 15 provided on the lens board 12. The lens unit 5 has a built-in photographing lens 16, an electronic shutter 17, and an EEPROM 18 (see FIG. 4) for storing the number of operations of the electronic shutter 17. The aperture value of the electronic shutter 17 is set by operating an aperture lever 19 provided outside the lens unit 5, and is driven under the control of the camera body 3.

On the rear side of the lens unit 5 and on the front side of the lens board 12, a main body control unit 21 including an electronic shutter 17 and an EEPROM 18 of the lens unit 5 and a CPU incorporated in the camera main body 3 are provided. (FIG. 4
Connectors 22 and 23 for electrically connecting
Are provided respectively. The lens board 12 and the camera body 3 are electrically connected by a flexible cord wired in the bellows 13.

In front of the rear opening 11 in the camera body 3, a light-shielding plate 25 for closing the opening 11 in a light-tight manner, a mirror 26 for changing the optical path of subject light, and a mirror mechanism 27 for driving these are provided. Is arranged. The light-shielding plate 25 and the mirror 26 are moved between a lowered position where the opening 11 is closed around the shaft attachment portion 28 and a raised position where the opening 11 is opened by rotating in the direction of arrow X in the drawing. It is supposed to be movable. When the light shielding plate 25 and the mirror 26 are at the lowered position, the subject light is reflected by the mirror 26 and travels upward of the camera body 3.

On the upper surface of the camera body 3, a focus glass 2 is provided.
The subject light reflected by the mirror 26 at the lowered position is incident on the focus glass 29 to form an image. A foldable waist level finder, an angle finder for converting an image formed on the focus glass 26 to an eye level, an AE finder 6 shown in the drawing, and the like are mounted on the upper portion of the camera body 3 according to shooting conditions and applications. .

The AE finder 6 is a finder optical system equivalent to an angle finder that bends the subject light formed on the focusing glass 29 so as to be viewed as an erect image. The AE finder 6 is formed on the focusing glass 29. And a light receiving element (not shown) for measuring the brightness of the subject light. The finder optical system of the AE finder 6 has a built-in display meter for displaying an aperture value and a shutter speed, so that the user can check the aperture value and the shutter speed while looking through the AE finder 6. Although not shown in detail, the AE finder 6 is electrically connected to the main body control unit 21 in the camera main body 3 at the lower part of the AE finder 6 and the upper surface of the camera main body 3, and the power supply of the camera main body 3 is Connectors for supplying the AE finder 6 are provided.

On one side surface of the camera body 3, a shutter speed adjustment dial 32 for switching between a shutter speed and an AE mode, turning on / off the power of the single-lens reflex camera 2 and switching between film winding modes. Mode switch dial 33, mirror up switch 3 for forcibly moving mirror 26 in camera body 3 to the raised position
4, an operation panel 36 to which a shutter button 35 and the like are attached is provided. In addition, a liquid crystal panel (LCD) 37 for displaying the state of the camera such as whether or not it can be photographed and a warning or an error display such as a remaining battery level or abnormal exposure is provided on the upper surface of the camera body 3 beside the focus glass 29. Is provided. A backlight is incorporated in the LCD 37 so that display contents can be checked even in a dark place.

A battery pack (not shown) serving as a power source for the single-lens reflex camera 2 is attached to the side of the camera body 3 opposite to the operation panel 36. In the single-lens reflex camera 2 of the present embodiment, an AC power supply can be used instead of the battery pack.

The focus adjustment mechanism 8 includes a base 40 mounted on the lower surface of the camera body 3, a pair of focusing rails 41 and 42 projecting forward from the base 40, and the focusing rails 41 and 42.
And a slide portion 43 on which the lens board 12 is mounted. Slide part 4
An operation knob 4 that is operated to move the slide portion 43 along the focusing rails 41 and 42 is provided on a side of the operation knob 4.
4 is rotatably mounted. This operation knob 44
When the is rotated, the slide unit 43 moves along the focusing rails 41 and 42, and the focus is adjusted by changing the distance between the camera body 3 and the lens unit 5.

The lens board 12 is mounted on a frame 47 mounted on the slide 43. The frame portion 47 is slidable and rotatable in a left-right direction orthogonal to the sliding direction of the slide portion 43. The lens board 12 is attached to the frame unit 47 so as to be rotatable in a vertical direction perpendicular to the rotation direction of the frame unit 47. Thus, the single-lens reflex camera 2 can perform tilting photography without using a special device.

In the film holder 4, a film loading chamber 50 in which a brownie-size photographic film 49 is loaded.
And an aperture 51 for defining an exposure range for the photographic film 49. Various sizes of masks are attached to the aperture 51, and the photographing size can be changed as appropriate. Aperture 5
A light-shielding cover 52 that shields light between the opening 11 of the camera body 3 and the aperture 51 when the film holder 4 is removed from the camera body 3 is inserted in front of 1. This shading lid 5
2 is taken out of the film holder 4 at the time of photographing.

Further, the film holder 4 includes the camera body 3
The rotation of the film holder 4 without changing the position of the single-lens reflex camera 2 makes it possible to switch the vertical and horizontal directions of the shooting screen. The display range of the focus glass 26 is also switched between vertical and horizontal in conjunction with the rotation of the film holder 4.

The photographic film 4 is placed in the film holder 4.
The first frame of No. 9 is set in the aperture 51, and the photo film 49 is wound up by one frame for each photographing.
Furthermore, after all frames have been shot, the photo film 49 is displayed.
Mechanism 5 consisting of gears, motors, etc. that wind up all
3 are incorporated. Although not shown in detail,
Connectors are provided on the back side of the camera body 3 and on the front side of the film holder 4, respectively, so that the main body control unit 21 in the camera body 3 and the control circuit in the film holder 4 can be electrically connected. . On the upper surface of the film holder 4, an LCD 54 for displaying various information of the loaded photo film 49 and information of the single-lens reflex camera 2 is provided.
An operation panel (not shown) for switching the display of the CD 54 is provided.

FIG. 4 is a block diagram showing a circuit configuration of each unit of the single-lens reflex camera 2. In the camera main body 3, a main body control section 21 for controlling each part of the camera main body 3 and for controlling the connected lens unit 5, film holder 4, and AE finder 6 is provided. The main body control unit 21 includes a circuit for driving and controlling a CPU, a RAM, a ROM, and a shutter, a circuit for controlling input and output of signals to and from the film holder 4 and the AE finder 6, and an LCD.
37, a circuit for driving the A / D converter 37, and the like.

The main body control unit 21 automatically identifies the type of the attached photographing unit via a connector electrically connected to each photographing unit, and controls the unit according to the attached photographing unit. I do. For example, in the case of the lens unit 5, the main body control section 21 sends a control signal to the electronic shutter 17 via the connectors 22 and 23. The electronic shutter 17 generates an S signal and an ST signal in response to the control signal, and inputs them to the main body control unit 21. The main body control unit 21 identifies the presence / absence, type, and state of the lens unit 5 based on the S signal and the ST signal.

From the electronic shutter 17 to the main controller 2
The S signal sent to 1 is an identification signal indicating the type of shutter, and is "H" level in the case of an electronic shutter, and "L" level in the case of a mechanical shutter. S
The T signal is an exposure start recognition signal, and is transmitted when the shutter is charged when the electronic shutter 17 is operating normally. This ST signal is also used to determine the state of shutter charge. There are also a new type and an old type of lens unit having a built-in electronic shutter. The new type lens unit 5 incorporates an EEPROM for storing the number of operations, and the old type lens unit has an EEPROM. Not included.

The camera body 3 contains the above-described LC.
D37, a mirror mechanism 27, an operation panel 36, a motor 56 for driving the mirror mechanism 27, and a driver 5 for driving the motor 56 under the control of the main body control unit 21.
7, a mirror detection sensor 58 that detects the rotation and rotation of gears and the like that constitute the mirror mechanism 27 to detect the positions and operating states of the light shielding plate 25 and the mirror 26, an EEPROM 59 that stores the number of times the mirror mechanism 27 has been operated, and an error or warning state. A buzzer 60 or the like that emits a warning sound when an alarm occurs is provided.

In the single-lens reflex camera 2 of the present embodiment, when the power is turned on by the mode changeover switch 33, when various switches are operated, during the shooting sequence, and at regular time intervals, timers are interrupted. A monitoring program that monitors the warning and error conditions of the unit is activated. The monitoring program includes a shutter check program for checking the presence / absence, type, operation state, and the like of the lens unit 5, and a mirror check program for checking whether the mirror 26 can be moved when the mirror up switch 34 is operated. There is.

In the shutter check program, the presence or absence and the type of the lens unit 5 are identified using the S signal and the ST signal generated by the lens unit 5, and the operation state is monitored. Further, the shutter check program monitors removal of the lens unit 5 when the mirror is raised, sounds the buzzer 60, and warns the user. Further, when the lens unit 5 is attached after the warning or the mirror 26 is moved to the raised position and the photographing path is blocked, the photographing of the frame already exposed due to erroneous operation is prohibited. The shutter release for one minute is prohibited, and the film of the frame is wound up.

In the mirror check program, the movement of the mirror 26 to the raised position in a state where the lens unit 5 is not attached is monitored, and in order to prevent the photographic film 49 from being carelessly exposed, a warning by the buzzer 60 and a mirror up are performed. The operation of the switch 34 is invalidated. The shutter check program and the mirror check program can prevent exposure of the photographic film 49 due to an erroneous operation. If the photographic film 49 is exposed due to an erroneous operation, a warning is surely given to the user, and further unnecessary exposure is performed. Can be prevented.

Next, the operation of the above embodiment will be described with reference to the flowcharts of FIGS. In the single-lens reflex camera 2, the shutter is turned on in accordance with the flowchart shown in FIG. 1 when the power is turned on by the mode changeover switch 33, when various switches are operated, during the shooting sequence, and by a periodic timer interrupt. The check program starts.

The main body control section 21 inputs a control signal for starting a check to the lens unit 5 via the connectors 22 and 23 when the shutter check program is started. When the shutter incorporated in the lens unit 5 receives the control signal for starting the check from the main body control section 21, it generates an S signal and an ST signal in response to the control signal.
Enter 1

The main body controller 21 controls the S of the lens unit 5
The presence or absence of the signal and the ST signal determines whether or not the lens unit 5 is attached to the front of the camera body 3. When the S signal and the ST signal are input, the level of these signals determines whether the shutter is an electronic shutter or a mechanical shutter. If the shutter is a mechanical shutter, a mechanical shutter is attached. Is stored in the RAM in the main body control unit 21 and used for various photographing controls.

When the attached lens unit 5 has a built-in electronic shutter, shutter charge is performed. The main body control unit 21 checks the operation state of the electronic shutter according to the ST signal input when the shutter is charged. Next, the main body control unit 21 checks the state of the mirror 26 with reference to the detection result of the mirror detection sensor 58. At this time, if the mirror 26 is in the raised position,
The electronic shutter is closed to prevent the photographic film 49 from being inadvertently exposed.

The main body control unit 21 determines whether the electronic shutter incorporated in the lens unit 5 is a new type or an old type. This identification is performed by the EEP in the lens unit 5.
A process of reading data from the ROM 18 is performed. If the data can be read, the data is stored in the RAM as a new electronic shutter. If the data cannot be read, the data is stored in the RAM as an old electronic shutter.
To memorize.

Further, the main body control section 21 outputs the S signal and the ST signal.
If no signal is obtained, it is determined that the lens unit 5 is not attached, and it is determined in the RAM that there is no shutter.
And whether the lens unit 5 was attached at the time of the previous monitoring is checked with reference to the stored contents of the RAM. If the lens unit 5 is not attached even at the time of the previous monitoring, it is determined that the lens unit 5 is not attached by the user's intention, and the shutter check is ended.

Contrary to the result described above, when the lens unit 5 is attached at the time of the previous monitoring, the main body control section 21 checks the state of the mirror 26 by referring to the detection result of the mirror detection sensor 58. . When the mirror 26 is at the lowered position, there is no problem because the inside of the film holder 4 is shielded from light, and it is determined by the user that the lens unit 5 is not attached, and the shutter check is terminated.

When the lens unit 5 is not mounted and the mirror 26 is at the raised position, the main body control section 21 sounds the buzzer 60 to warn the user. The warning by the buzzer is given for a fixed time by a timer or the like. After the warning processing for the user is performed, the main body control unit 21 sets “1” to the shutter warning flag, and ends the shutter check.

While the power of the single-lens reflex camera 2 is turned on, a shutter check is periodically performed. However, until the lens unit 5 is attached or the mirror 26 is moved to the lower position, the shutter warning flag indicates “1”. Is set. For example, when the mirror up switch 34 is operated during the warning period and the mirror 26 is moved to the lowered position, the photographic film 49 is prevented from photographing one frame of the carelessly exposed photographic film 49. Is wound up for one frame. After this processing, the shutter warning flag is reset to “0”.

When the lens unit 5 is attached to the front of the camera body 3 during the warning period, the shutter type is determined and the shutter type is stored in the RAM. Thereafter, since the shutter warning flag remains “1”, the presence / absence of the shutter is confirmed again with reference to the RAM. At this time, if it is recognized that the shutter is present, the shutter release for one frame is prohibited so that the photographing of one frame of the photographic film 49 which is carelessly exposed is not performed, and one frame of the photographic film 49 is further prevented. The minute is wound up. After this processing, the shutter warning flag is reset to “0”.

As described above, when the lens unit 5 is detached while the mirror 26 is at the raised position, the buzzer 60 gives a warning, so that the user can immediately recognize that an erroneous operation has been performed. be able to. Also, when the lens unit 5 is attached after the warning or the mirror 26 is moved to the lowered position and the photographing optical path is shielded, the photographing is not performed on one frame of the photographic film 49 that has been carelessly exposed. Since the shutter release for one frame is prohibited and the photo film 49 is wound up for one frame, a photographing mistake can be prevented, and the next photographing can be performed immediately.

In the above-described shutter check program, a check is performed when the lens unit 5 is detached when the mirror 26 is at the raised position. As shown in the flowchart of the mirror check program in FIG.
When the mirror up switch 34 is operated, the presence or absence of the lens unit 5 is detected, and the movement of the mirror 26 is prohibited or permitted.

When the mirror up switch 34 is operated, the main body controller 21 checks the voltage of the battery pack attached to the camera main body 3. This is to prevent the battery pack from being exhausted when the mirror 26 is moved to the raised position or the lowered position, and the mirror 26 does not move from the moved position. If an AC power supply is used instead of the battery pack, the check of the power supply voltage may be omitted.

If the voltage of the battery pack has dropped after checking the power supply voltage, the operation of the mirror up switch 34 is ignored and the mirror check program ends. At this time, the LCD 37 of the camera body 3
Alternatively, a low battery warning may be displayed on the LCD 54 of the film holder 4.

If the voltage of the battery pack is OK, a shutter check is performed according to the flowchart of FIG. The purpose of this shutter check is to identify whether or not the lens unit 5 is attached to the camera body 3. Next, the main body control unit 21 detects whether the mirror up switch 34 is operated on the UP side or the DOWN side. If the lens unit 5 is not attached even though the mirror up switch 34 is operated to the UP side, a warning is issued to the user by the buzzer 60 and the operation of the mirror up switch 34 is ignored.

When the mirror up switch 34 is operated to the UP side and the lens unit 5 is attached, the mirror 26 is moved to the raised position. Further, when the mirror up switch 34 is operated to the DOWN side, the mirror 26 is moved to the lowered position regardless of the presence or absence of the lens unit 5.

As described above, when the mirror up switch 34 is operated, the presence or absence of the lens unit 5 is checked, and the mirror up switch 34 is operated to the UP side even though the lens unit 5 is not attached. If so, a warning is issued and the operation of the mirror up switch 34 is invalidated, so that careless exposure of the photographic film 49 can be reliably prevented.

In the above embodiment, a warning is issued by a buzzer. However, the present invention is not limited to this. For example, the warning may be displayed on an LCD, or the backlight of the LCD may be turned on or blinked. Further, although the description has been made of the lens shutter type single-lens reflex camera as an example, the present invention can be applied to a single-lens reflex camera in which a focal plane shutter is incorporated in a camera body.

[0047]

As described above, according to the single-lens reflex camera of the present invention, the wrong lens unit can be removed,
Inadvertent exposure of the photographic film by mirror operation can be effectively prevented. Further, when the photographic film is exposed due to an erroneous operation, the user can be reliably warned. Further, since the photographing is not performed on the carelessly exposed photographic film, the problem that the photographed frame cannot be found does not occur.

[Brief description of the drawings]

FIG. 1 is a flowchart of a shutter check.

FIG. 2 is a perspective view illustrating an appearance of a single-lens reflex camera.

FIG. 3 is a side view and a sectional view of a main part of the camera.

FIG. 4 is a block diagram showing an electrical configuration of the camera.

FIG. 5 is a flowchart of a mirror check.

[Explanation of symbols]

 2 Single-lens reflex camera 3 Camera body 4 Film holder 5 Lens unit 6 AE finder 17 Electronic shutter device 26 Mirror 27 Mirror mechanism 34 Mirror up switch 49 Photo film

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tokuji Sato 3-13-45 Izumi, Asaka-shi, Saitama Fuji Photo Film Co., Ltd.

Claims (3)

[Claims] A camera body having a built-in mirror that moves between a raised position for opening a photographing optical path and a lowered position for closing the photographing optical path and simultaneously forming a finder optical path;
In a single-lens reflex camera including a shutter device and a taking lens, and a lens unit attached to the camera body, a warning is issued when the lens unit is detached from the camera body when the mirror is at the raised position. A single-lens reflex camera characterized by performing. 2. When the photographing optical path is blocked after the warning, shutter release for one frame is prohibited,
The single-lens reflex camera according to claim 1, wherein the photographic film is fed by one frame. 3. A camera body having a built-in mirror which moves between a rising position for opening a photographing optical path and a lowering position for closing the photographing optical path and simultaneously forming a finder optical path;
In a single-lens reflex camera including a shutter device and a photographing lens, and a lens unit attached to the camera body, an operation of moving a mirror to a raised position when the lens unit is not attached to the camera body. A single-lens reflex camera characterized by being invalidated.