JPH0425527B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an autoload camera in which film is automatically wound by a motor.

Conventionally, a film winding motor was built into the camera body, and was controlled by multiple switches placed in various parts of the camera to wind the film for each shot and to feed the film by a predetermined amount when loading the film. Cameras are known, for example, from Japanese Utility Model Publication No. 42-22329 and Japanese Patent Publication No. 43-5946. However, in these known cameras, each switch is directly connected in series within the circuit that includes the battery and motor, so the excessive current that occurs when the motor starts generates sparks at the switch contacts. There were drawbacks that not only shortened the lifespan of the switch, but also caused it to malfunction. In addition, in the known camera, one frame of film is not wound at the end of the film, and no consideration is given to the case where the film winding stops midway, resulting in damage to the perforation part of the film and This method has major disadvantages such as accidents such as cutting the film during return, burning out the coil of the motor due to the excessive load placed on the motor, and consumption of the battery.

The present applicant has proposed an automatic film winding camera with a built-in electric motor that eliminates these drawbacks and operates smoothly, as disclosed in Japanese Patent Laid-Open No. 55-43502.
However, in the invention described in the specification of the above publication, the main switch is a normally open switch that is turned on by closing the camera back only when there is film in the film chamber of the camera, so it is necessary to check the winding mechanism of the camera. However, it is necessary to load film into the film chamber each time, which is inconvenient for inspecting the camera other than when shooting.

The present applicant has filed Japanese Patent Application No. 151178/1983 for the purpose of providing an automatic film winding camera using a motor that eliminates the above-mentioned drawbacks and operates smoothly. The invention described in the application specification includes a switch that is closed when the back cover is closed regardless of whether or not a film is loaded into the film chamber, a switch that is closed during the film idling time in conjunction with a film counter, and a switch that is closed when the film is wound by a motor. In an automatic film winding camera equipped with an operating switch, a first electronic circuit for controlling the operation of the switch is provided in the power supply circuit to the motor, and the switch is operated through the first electronic circuit during the film feeding time. The present invention proposes an automatic film winding camera equipped with a second electronic circuit for controlling the film, and a third electronic circuit for stopping power supply to the motor through the first electronic circuit after a certain period of time has elapsed during film winding. The motor is controlled by a combination of many installed mechanical switches and an electronic circuit that performs the switching action, and even when each mechanical switch is activated, the current flowing through the electronic circuit is extremely small. Because it is small and does not generate sparks between the contacts,
The life of each switch is not shortened and malfunctions do not occur. In addition, it is not only possible to reliably feed a predetermined length of film and wind the film at each shooting time.
Even if one frame of film is not wound at the end of the film and the film stops mid-way, the power supply to the motor is stopped after a certain period of time, so there is no need to burn out the coil or waste battery power due to excessive current. It has a positive effect.

However, by adopting a well-known autoloading mechanism on the film winding shaft side of the camera and combining it with the proposal in Japanese Patent Application No. 54-151178, an autoloading camera with fully automated film loading and winding was completed. However, it turned out that this was not the case. That is, in a fully automated autoload camera, when a cartridge containing film is loaded into the camera and the back cover is closed, the film is automatically wound to a predetermined length and the first frame of the film can be photographed. When you press the shutter release button, a picture is taken and the next frame is rolled up. The film is wound one after another as the photo is taken.
When the end of the film is reached, one frame of film is not wound up, and the film becomes taut during winding and is stopped. In cameras that automatically rewind the film, the motor is reversed to rotate the cartridge shaft in the rewinding direction based on information such as the film tension in the stretched state or the film stopping mid-frame, and the film is rewinded. It will be done. In a camera in which the film is manually rewound, the cameraman rewinds the film by disconnecting the motor such as the film winding shaft or sprocket and rotating the cartridge shaft in the rewinding direction.

At this point, when the film is completely rewound, it is in the same state as when a new cartridge is loaded into the camera and the back cover is closed, so the film is auto-loaded again and wound up to the first frame. There remains the problem of being lost.

The present invention has been made for the purpose of providing an autoloading camera that distinguishes between the end of rewinding and loading of a new cartridge for autoloading, and autoloads only when a new cartridge is loaded. The above purpose is to provide a first switch that outputs a pulse during the camera back opening/closing operation, a second switch that outputs camera back open information indicating the open state of the camera back, and camera back close information indicating the closed state of the camera back; a control circuit that controls the prohibition and start of the autoload operation based on the back cover open information and the back cover close information output from the second switch; and the control circuit based on the pulse output from the first switch. and timer means for operating the switch for a predetermined period of time, the timer means operates based on the pulse output from the first switch, and while the control circuit is in the operating state, the control circuit operates the second switch. When camera back opening information is detected by
This is achieved by an autoload camera characterized in that the autoload operation is started when back cover closing information from a switch is detected.

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a cross-sectional view of an autoload camera, showing a film F having perforations on both sides loaded inside a camera body 1. Patrone P with built-in film
is loaded into the camera body 1 and the back cover 2 is closed.

One end of the film F is attached to the cartridge shaft 7 and wound around the cartridge shaft 7. The other end of the film passes through the film exposure opening 3, the perforation of the film F meshes with the sprocket teeth of the sprocket 4, and the leading end of the film F is guided by the film guide 5 and wound onto the take-up shaft 6. . The driving force of a motor powered by a battery is transmitted to the winding shaft 6 to wind up the film F, and when the sprocket 3 rotates once, one frame of film is transferred and then stopped.

Now when the shutter release is turned off on the camera,
The film is exposed, and when the film exposure is completed, a film advance start signal is issued, a motor drive signal is issued, the film is moved by one frame, and preparations are made for the next shutter release. The motor-winding camera automatically winds the film in this way, but when one roll of film in the cartridge has been photographed, the motor and winding shaft 6 are automatically or manually disconnected. Rewinding is performed by rotating the cartridge shaft 7 clockwise.

Figure 2 shows sprocket 4 and the micro switch S _SP installed around it.
A cam 41 is provided on the shaft of the rotating sprocket 4, and is designed to issue a transport signal for each frame as the film is wound up or rewound.

Figure 3 shows a back cover opening/closing pulse switch S _K newly provided in accordance _with the present invention. The protrusions 21 provided provide short-term contact and pulse generation.

Figure 4 also shows a back cover opening _/ closing switch S _B newly provided according to the present invention. The state is maintained and the ON state is maintained while the lid is open.

Figure 5 shows an example of the built-in camera.
This shows a block diagram of the control circuit using ICs, etc. Figure 6 shows the auto-rewind operation, opening the camera back, taking out the photographed cartridge, loading a new cartridge, and closing the lid to start auto-loading. This is a mime chart showing the state of preparation for shooting.

When the film in the camera reaches its end, the signal causes the motor to reverse, rotate the cartridge shaft 7 in the rewinding direction (clockwise), and the photographed film is collected into the cartridge. During the film rewinding process, the sprocket 4, which meshes with the perforation of the film through its sprocket teeth, is rotated clockwise, and the micro switch Ssp generates one signal for each revolution of the sprocket. The control circuit is
The timer operates for each Ssp signal, and when the next Ssp signal comes, it is cleared and the timer operates again, but the set time
If the next Ssp signal does not come even after reaching T _A , it is determined that film rewinding has been completed, a buzzer indicating the rewinding completion is sounded, and when the warning time T _BZ has elapsed, the ICs that make up the control circuit etc. are in power hold. Solve the IC
Reduce the power supply voltage Vcc.

When camera back 2 is opened, camera back open/close switch S _B is
It becomes ON. In addition, the back cover opening/closing pulse switch S _K emits a pulse signal in conjunction with the opening operation, and based on the pulse generation, the IC is activated, and a timer is activated for a certain period of time (for example, 5 seconds) as the IC is activated. During operation, power is held and Vcc is supplied to the IC. While the IC is in operation, the open/close status of the back cover can be detected, and at a predetermined timing within the T _O time, the status of the back cover open/close pulse switch S _K is detected and the back cover open/close switch is activated. When it is detected that S _B is in the open state, that is, in the ON state, the film winding operation is not performed. Then, when the set time _TO has elapsed, the supply of the IC power supply Vcc is cut off.

When replacing the cartridge with a new cartridge and closing the back cover 2, the back cover opening/closing pulse switch S _K
generates a pulse signal, and based on the pulse generation, the IC becomes activated in the same manner as described above and T. When the timer operates and the power is held, the IC
Power supply Vcc is supplied. At this time, the back cover open/close switch S _B is in the closed state, that is, in the OFF state, so the IC detects that the back cover is closed this time, and the motor rotates for 3 frames to wind the film, making it ready for shooting. and stop.

Since it is configured as explained above,
The present invention has the effect that the accidents that often occur with conventional autoload cameras, such as autoloading the already shot film again after rewinding the film and before replacing the cartridge, do not occur at all. Ta.

Further, since unnecessary power is not supplied to the IC after the rewinding is completed, unnecessary power consumption can be prevented.

[Brief explanation of drawings]

Fig. 1 shows a sectional view of the camera, Fig. 2 shows a switch installed in the sprocket, Figs. 3 and 4 show a switch newly provided according to the present invention, and Fig. 5 shows a control circuit. The block diagram is shown and the sixth
The figure shows a time chart from film rewind to shooting preparation state. 1... Camera body, 2... Back cover, 4... Sprocket, 6... Winding shaft, 7... Cartridge shaft,
Ssp, S _K , S _B ... Micro switch.

Claims (1)

[Claims] 1. In an autoloading camera that starts autoloading of film by closing the camera back cover, the first
a second switch that outputs camera back open information indicating the open state of the camera back and camera back close information indicating the closed state; and the camera back open information and camera back close information output from the second switch. and a timer means for keeping the control circuit in an operating state for a predetermined period of time based on the pulse output from the first switch. A timer means is activated based on the pulse output from the first switch, and when the control circuit detects camera back opening information from the second switch while the control circuit is in the operating state, the automatic loading is prohibited; The autoload camera is characterized in that the autoload operation is started when back cover closing information is detected by the second switch.