JP3431675B2 - instant camera - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instant camera, and more particularly, to an instant camera devised for cleaning a developing roller. 2. Description of the Related Art An instant camera using a self-developing film unit has a great feature that a print photograph can be obtained on the spot, and is used for various purposes. Above all, with an instant camera using a mono-sheet type film unit,
When the release button is pressed and the exposure is completed, the well-known scraping claw moves in conjunction with this and moves through the notch formed in the exposure frame of the film pack to remove the topmost film unit stacked in the film pack. Scrape out. In the scraped-out film unit, the developing solution pod is split open by a pair of developing rollers, and the developing solution contained in the developing solution pod is spread, and then discharged out of the camera. At this point, the film unit has completed the necessary processing, and a print photograph can be obtained after a predetermined time has elapsed. In the above-described instant camera, when the developing solution adheres to the developing roller, the developing roller must be cleaned. This is because if the developing solution is left attached, the developing solution hardens on the surface of the developing roller, causing uneven development. For this reason, the conventional instant camera has a structure in which the developing roller can be removed or a structure in which the developing roller can be exposed in consideration of maintainability. However, such a structure increases the number of parts and leads to an increase in cost.In addition, removing the developing roller may cause a secondary failure or cleaning the entire circumference of the developing roller even if the developing roller is exposed. There was a problem that can not be. From such a background, the present applicant has proposed an instant camera provided with a dedicated reversing button for reversing the developing roller in order to solve these problems (Japanese Patent Laid-Open No. 4-194829). [0004] However, as described above, the method of operating the reverse button to reverse the developing roller does not remove the cause of secondary failure caused by removing the developing roller. Although it is possible, there is a problem that in addition to increasing the number of parts by newly providing a dedicated reversing button, it is disadvantageous to downsize the instant camera because a new space for incorporating the reversing button is required. . An object of the present invention is to provide an instant camera which solves the above-mentioned problems, is advantageous for miniaturization, and enables easy maintenance of a developing roller. In order to achieve the above object, the present invention provides a back cover opening / closing detecting means for detecting opening / closing of a back cover which is opened / closed for loading an instant film unit, and a developing roller. And a controller for rotating the developing roller in reverse by pressing the release button when the back cover is opened by the back cover opening / closing detecting means. When the back cover is opened, the back cover switch detects that the back cover is open. When the release button is pressed in this state, the developing roller rotates in the reverse direction. Therefore, the developing roller can be cleaned from the film pack storage chamber side in a state where the film pack storing the instant film unit is not loaded. When the back cover is closed, the photographing is performed by pressing the release button, and after the exposure to the instant film unit is completed, the developing roller is rotated forward to perform the developing process and the discharging of the film unit. . FIG. 2 shows a state of use of an instant camera embodying the present invention. The camera body of this instant camera has a main body 1 having a thin box-like contour, a lens board 2, and a A lens stay 3 for holding the lens board 2 from below;
And a bellows 4 which covers the photographing optical path. [0009] The lens board 2 has a main body 1
When not in use, it can be folded compactly around the shaft 5 so as to cover the front surface of the main body 1 (not shown). When the lens board 2 is standing up, as shown in FIG. 2, the lens stay 3 having the tip mounted on the lens board 2 slides along the guide groove 3a on the guide pin 6 so as to turn around from the rear side of the main body 1. Move,
The rear end is locked to the lower end of the main body 1 to hold the lens board 2 in an upright state. The lens board 2 has a photographic lens 7 on the front,
A photographing unit 8 (see FIG. 3) including an automatic exposure circuit, a shutter mechanism, and an aperture mechanism is provided inside the front surface, and a battery chamber 9 is provided as shown in FIG. The battery compartment 9 accommodates a battery 10 composed of a lithium battery as a power source for each part, and is covered with a battery cover 9a. As shown in FIG. 2, a release button 11, a strobe 12, a finder 1
3 is provided, and a photographed film unit 22 is provided on the upper surface.
Is provided with an outlet 14 from which the liquid is extracted. The release button 11 is used as a trigger button for operating the photographing unit 8 to develop and discharge the film unit 22 during normal use, but is used as a roller cleaning button when the back cover 18 described later is open. FIG.
As shown in FIG. 1, a release switch 15 for electrically detecting a pressing operation of the release button 11 is provided behind the release button 11.
When 1 is pressed, a release signal is sent from the release switch 15 to the CPU 16 (see FIG. 3). As shown in FIG. 3, the photographing unit 8 operates the aperture mechanism and the shutter mechanism with the exposure pulse signal generated from the CPU 16, and sends an exposure completion signal to the CPU 16 after the operation is completed. The strobe 12 is driven by the driver 12a in synchronization with the operation of the photographing unit 8 when the subject brightness is low, and emits light for each photographing. As shown in FIG. 1, on the back of the main body 1,
A back cover 18 is provided via a hinge 17, and a back cover switch 19 for electrically detecting opening and closing of the back cover 18 is provided on the main body 1 side near the hinge 17. The back cover switch 19 is set to “ON” when the back cover 18 is completely closed to the main body 1, and “O” when the back cover 18 is open.
FF "is sent to the CPU 16 as a back cover signal. The back cover switch 19 is a switch that is conventionally provided in an instant camera for detecting opening and closing of the back cover 18. When the back cover 18 is opened, the film pack storage chamber 20 on the main body 1 side is exposed, and a film pack 21 can be loaded into the film pack storage chamber 20.
The film pack 21 includes a mono-sheet type film unit 22 provided with a developer pod 22a, which is stacked and pressed against an opening frame provided in the film pack 21 by a spring 21a. In the opening frame, the exposed film unit 22 is moved upward with the claw member 23 (FIG. 3).
Cut-outs are provided for scraping out at the same time. Above the film pack storage chamber 20, a pair of developing rollers 24 for crushing the developer pod and developing the developing solution on the photosensitive emulsion surface while discharging the exposed film unit 22 are provided.
Is built-in. As shown in FIG. 3, the claw member 23 moves the notch portion of the opening frame of the film pack 21 by the claw driving mechanism 26 to scrape out the uppermost film unit 22 stacked in the film pack 21. It is sent to the developing roller 24. The driving force is transmitted to the claw driving mechanism 26 from a motor 28 via a one-way clutch mechanism 27. The one-way clutch mechanism 27 is a clutch device that transmits the driving force of the motor 28 to the claw drive mechanism 26 only when the motor 28 rotates forward. The rotation of the motor 28 is controlled by a roller driving mechanism 29.
And is also transmitted to the developing roller 24. The roller drive mechanism 29 rotates the developing roller 24 in the normal rotation direction for discharging the film unit 22 when the motor 28 rotates forward, and the developing roller 2 when the motor 28 rotates in the reverse direction.
4 is rotated in a direction opposite to the direction in which the film unit 22 is discharged. The driver 28a rotates the motor 28 forward or reverse according to a signal input during a period during which the normal rotation signal or the reverse rotation signal from the CPU 16 is input. The CPU 16 includes a ROM in which a program necessary for control is written and a RAM in which necessary variables and the like are stored.
And a timer function. The operation of the instant camera configured as described above will be described. FIG. 4 shows a flowchart of the basic processing of the CPU 16. In the case of normal shooting, shooting is performed with the camera in use as shown in FIG. In this state, the film pack storage chamber 20 is loaded with the film pack 21 and the back cover 18 is completely closed. The photographer presses the release button 11 as is well known. As a result, a release signal is sent from the release switch 15 to the CPU 16. The CPU 16 to which the release signal has been input,
Since the back cover signal from the back cover switch 19 is “ON”, an exposure pulse signal is generated and sent to the photographing unit 8. The photographing unit 8 determines an aperture value corresponding to the subject brightness, and sets the aperture of the aperture mechanism based on the aperture value. When the subject brightness is low, the flash 12 emits light via the driver 12a in synchronization with the shutter.
Further, the photographing unit 8 opens and closes a shutter based on the exposure pulse signal. Thus, the subject light incident from the photographing lens 7 is exposed to the film unit 22. After the operation, the imaging unit 8 sends an exposure completion signal to the CPU 16 indicating that the exposure has been completed. When the exposure completion signal is input, the CPU 16 starts sending a forward rotation signal to the driver 28a.
The motor 28 is rotated forward by the driver 28a, and the rotation is reduced by the roller
4 and the developing roller 24 is moved to the film unit 22.
The rotation is started in the normal rotation direction in which on the other hand,
The driving force of the motor 28 is transmitted to the claw driving mechanism 26 via the one-way clutch mechanism 27, and drives the claw member 23. The claw member 23 sends out the exposed film unit 22 toward the developing roller 24 through a notch provided in the opening frame of the film pack 21.
During the feeding, the developing pod 22a of the film unit 22 is torn by the developing roller 24, and the developing solution contained in the developing pod 22a is uniformly spread on the surface of the photosensitive emulsion, and then discharged from the discharge port 14. . CPU16
Stops the transmission of the forward rotation signal and stops the rotation of the developing roller 24 after a predetermined time required for discharging the film unit 22 has elapsed. At this point, the film unit 22 has completed the necessary processing, and after a lapse of a predetermined time, a print photograph is obtained. The claw member 23
After the single film unit 22 is sent out, it returns to the initial position and stops. Next, a case where the developing roller 24 is cleaned will be described. The cleaning of the developing roller 24 is performed without loading the film pack 21 into the film pack storage chamber 20. In the state of use as shown in FIG. 2, the back cover 18 is opened as shown by the imaginary line in FIG. When the back cover 18 is opened, a back cover signal of “OFF” is sent from the back cover switch 19 to the CPU 16. When the release button 11 is pressed in this state, the CPU 16 sends a reverse rotation signal to the driver 28a only while the release button 11 is pressed. At this time, since no exposure pulse signal is generated, the photographing unit 8 does not operate. The driver 28a rotates the motor 28 in the reverse direction. The driving force of this reverse rotation is the one-way clutch mechanism 27
However, the one-way clutch mechanism 27 does not transmit the driving force to the claw driving mechanism 26 when the reverse-rotating driving force is input, whereby the clutch operates. Therefore, the claw member 23 does not move. On the other hand, the reverse rotation of the motor 28 is transmitted to the developing roller 24 via the roller driving mechanism 29, and the developing roller 24 starts rotating in the direction opposite to the discharge direction of the film unit 22. While the developing roller 24 is rotating in the reverse direction, a cleaning member such as a cotton swab is inserted from the film pack storage chamber 20 so that the developing roller 24 can be cleaned. At this time, when the cleaning member is brought into direct contact with the developing roller 24 to wipe it off, the developing roller 24 is
Since it is rotating in the direction opposite to the direction of discharging 2,
The cleaning member does not get caught in the developing roller 24 during the wiping operation. Further, instead of the swab, the processing liquid may be removed by using a cleaner that ejects a cleaning liquid from a nozzle. In the above embodiment, the release button 1
Although the reverse rotation signal is generated only while 1 is being pressed, a reverse rotation signal may be generated as shown in the flowchart of FIG. In this case, with the back cover 18 opened, release button 1
After the timer value T is reset to "0" when "1" is pressed, the timer is started and at the same time, a reverse rotation signal is sent to the driver 28a. Even when the release button 11 is released, the CPU 16 continues to send the reverse rotation signal until the timer value T reaches the preset value Tc, and stops the reverse rotation signal when the timer value T becomes equal to the specified value Tc. Then, the rotation of the developing roller 24 is stopped. In this way, it is not necessary to keep pressing the release button 11, so that cleaning can be performed using both hands. In each of the above embodiments, the back cover switch 1
9, the developing roller 24 is rotated in reverse to discriminate between normal photographing and cleaning. Instead, as shown in FIG. 6, an AND signal between the film pack switch 30 and the back cover switch 19 is used. , The developing roller 24 may be reversed. The film pack switch 30
It is provided in the film pack storage room 20 for resetting the number-of-photographs counter, so that it is not necessary to newly install it for cleaning the developing roller 24. As shown in FIG. 7, signals from the back cover switch 19 and the film pack switch 30 are detected, and the operation of the release button 11 causes the developing roller 24 to rotate in the reverse direction, thereby cleaning the roller. The same components as those in the above embodiment are denoted by the same reference numerals. As described above, according to the instant camera of the present invention, the state in which the back cover is opened is detected by using the conventional back cover open / close detection switch, and the back cover open state is detected. By operating the release button, the unfolding roller is rotated in the opposite direction to the discharge direction of the film unit, so it is possible to use a conventional release switch such as a back cover open / close detection switch and suppress an increase in the number of parts. . Further, since there is no need to provide a dedicated switch, it is advantageous for miniaturization.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of an instant camera embodying the present invention in use. FIG. 2 is an external view of the instant camera in use. FIG. 3 is a block diagram of a main part of the instant camera. FIG. 4 is a flowchart showing a control procedure of the instant camera. FIG. 5 is a flowchart illustrating another control procedure of the instant camera. FIG. 6 is a block diagram of the instant camera when a film pack switch is used together. FIG. 7 is a flowchart showing a control procedure when a film pack switch is used together. [Description of Signs] 1 Main body 11 Release button 15 Release switch 16 CPU 18 Back cover 19 Back cover switch 24 Roller 28 Motor 29 Roller drive mechanism

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G03B 17/00-17/17 G03B 17/22 G03B 17/26-17/34 G03B 17/38-17 / 55

Claims (1)

(57) [Claims] [Claim 1] Exposure to the instant film unit and normal rotation of the developing roller are performed by pressing the release button, and the instant film unit exposed by the developing roller is outside the camera body. Back opening / closing detecting means for detecting opening / closing of a back cover which is opened / closed for loading an instant film unit, and a roller driving mechanism for rotating forward / reversely the developing roller And a controller that reverses the developing roller by pressing the release button when the back cover is opened by the back cover open / close detection means.