JPH04324432A - Camera - Google Patents

Abstract

PURPOSE:To rapidly detect a state where pushing out a film ends in failure in such a case in a camera where a push out system film cartridge is used. CONSTITUTION:In the camera where the push out system film cartridge 1 which is equipped with a code member which has an information code concerning the film and which rotates integrally with a film supply spool is used, a rotation detecting means for detecting the rotating state of the code member from the information code of the code member, a film push out means for automatically pushing out the film from the cartridge after loading the cartridge, and a decision means for deciding that pushing out the film ends in failure in the case that the rotation detecting means can not detect the rotation even when a specified time elapses after starting the action of pushing out the film by the film push out means are provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera using a push-out film cartridge having a code member that is provided with information about the film and rotates integrally with a film supply spool.

0002

2. Description of the Related Art Conventionally, a so-called extrusion type film cartridge has been proposed in US Pat. No. 4,834,306, in which a film is completely housed in the cartridge and the leading edge of the film is pushed out from inside the cartridge by rotating a film supply spool. .

In this type of extrusion type film cartridge, when extruding the film from inside the cartridge, it is conceivable that the leading end of the film gets caught in the cartridge, making it impossible to extrude the film. In this case, the film supply spool is forcibly rotated by the camera's fork, which could lead to damage to the leading edge of the film or damage to the camera's gear system that drives the fork. .

[Object of the Invention] The present invention has been made in view of the above circumstances, and uses an extrusion type film cartridge that is equipped with a film-related information code and has a code member that rotates integrally with the film supply spool. In the camera, a rotation detecting means for detecting the rotation state of the code member based on the information code of the code member, and a film for automatically extruding the film from the cartridge after loading the film cartridge. The extrusion type film cartridge comprises an extrusion means, and a determination means for determining that extrusion has failed if the rotation detection means cannot detect the rotation even after a predetermined period of time has elapsed after the start of extrusion operation of the film by the film extrusion means. An object of the present invention is to provide a camera that can promptly detect a failure in film extrusion and prevent damage to the film or fork drive system.

[0005]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings.

FIGS. 6 and 7 are a perspective view and a top view of a push-out film cartridge used in a camera according to an embodiment of the present invention.

In FIGS. 6 and 7, 1 is a film cartridge, and 2 is a film supply spool, which has a fork engagement hole 2a that engages with a fork of a camera. Reference numeral 3 denotes a disk serving as a code member, which rotates integrally with the film supply spool 2 and is equipped with a bar code indicating information regarding the film in the cartridge, such as film sensitivity and prescribed number of frames.

FIG. 2 is a rear view of the camera according to the embodiment of the present invention, seen from the back side with the back cover removed.

In FIG. 2, 11 is a release button, 12 is a viewfinder, 13 is a camera body, 14 is a spool chamber,
15 is a film take-up spool, 16 is a film guide rail, 17 is a photoreflector that detects perforations in the film, 18 is an aperture for exposing the film, and 19 is the brightness of the bar code of the disc 3 shown in FIGS. 6 and 7. 20 is a fork that engages with the fork engagement hole 2a of the film cartridge 1 shown in FIG. 6 to rotate the film supply spool; 21 is a film cartridge chamber; This is a pin for detecting opening/closing, and is interlocked with the cartridge chamber cover switch 33 shown in FIG. 3, which will be described later.

FIG. 3 is a block diagram showing the electrical circuit of the camera of FIG. 2. In FIG. 3, 31 is a microcomputer that controls the entire camera sequence, and 32 is the release button 1 in FIG.
1 is a release switch that is linked to 1; 33 is a cartridge chamber cover switch that is turned on and off in conjunction with the pin 22 shown in FIG. 2; 34 is a photometry circuit; 35 is a distance measurement circuit; 37 is an encoder circuit that detects the film perforation signal from the photoreflector 17; 38 is a motor control circuit for feeding the film; Drive to extrude and feed the film,
Controls rewinding. Incidentally, the feeding system of this embodiment first includes the fork 2, as shown in Japanese Patent Application Laid-Open No. 2-67534.
0 extrudes the film from within the cartridge, and then when the leading end of the film wraps around the film take-up spool 15, the film is wound up by the film take-up spool 15 at a faster speed than the fork 20, and at this time, The driving force of the fork 20 is nullified by a one-way clutch system. 39 is a shutter control circuit, 40 is a lens control circuit, and 41 is a display circuit.

Next, the operation of the above configuration will be explained with reference to the flowchart of FIG. 1 showing the operation of the microcomputer 31.

In #1, whether or not the cartridge chamber cover 23 is closed is determined based on the state of the cartridge chamber cover switch 33 which is linked to the pin 22, and when it is determined that the cartridge chamber cover 23 is closed, the process proceeds to #2. The internal timer starts counting, and at #3, the motor control circuit 38 starts driving the fork 20 and film take-up spool 15. As a result, the fork 20 first pushes out the film from the film cartridge loaded in the cartridge chamber 21. At #4, the barcode signal of the disk 3 detected by the photoreflector 19 is input from the barcode encoder circuit 36. In #5, based on the barcode signal input in #4, it is determined whether or not there is a light/dark signal of the barcode (whether there is a change in light/darkness of the barcode), and if there is no light/dark signal, the disk 3 is rotated. If not, proceed to #6, and determine whether the timer that started counting in #2 has finished counting the predetermined time. If not, proceed to #6.
4, the input of the barcode signal from the barcode encoder circuit 36 is repeated. When it is determined in #6 that the counting of the predetermined time has ended, the disk 3 is determined to be unable to rotate, and the winding is stopped in #7, and in #8, the display circuit 41 indicates that extrusion has failed or autoloading (AL).
Display failure and proceed to #20.

That is, the leading edge of the film gets caught in the film cartridge or at the exit of the film cartridge, and cannot be pushed out by the supply spool 15.
It is determined that the rotation of the fork 20 has also been forcibly stopped.

On the other hand, if brightness or darkness of the barcode is detected in #5, the fork 20 is rotating, so the process goes to #9, the timer in #2 is reset, and the process goes to #10.

At #10, film information such as the specified number of frames of the film and film sensitivity is input based on the brightness of the barcode detected at #4.

At #11, a perforation signal of the film is received from the encoder circuit 37, and it is determined whether the film has been fed to the first frame. When the first frame is reached, the film feeding is stopped at #12. do.

At #13, it is detected whether or not the release button 11 has been pressed, and when the release switch 32 is turned on, the process advances to #14. In #14, the photometric circuit 34 measures the brightness of the subject. In #15, distance measuring circuit 35
The distance to the subject is measured.

At #16, a lens (not shown) is controlled by the lens control circuit 15 so that the distance measured at #15 is brought into focus.

At #17, the shutter is controlled by the shutter control circuit 39, and the film is exposed in accordance with the value measured at #12.

At #18, one frame of film is wound based on the outputs of the motor control circuit 38 and encoder circuit 38.

At #19, an internal counter determines whether or not all frames of film that can be photographed have been used.
If it has not finished, return to #13, if it has finished, return to #2
Go to 0.

In #20, the motor control circuit 38
Rewinding of the film is started, and at #21, it is detected whether or not the film is no longer on the aperture 18 based on the film perforation signal inputted from the photoreflector 17 to the encoder circuit 37, and it is detected that the film is no longer present. When detected, a predetermined time is counted so that the entire film is wound into the film cartridge in step #22, and then the rewinding operation is stopped in step #23.

#24 is the cartridge chamber cover switch 33.
The process waits until the cartridge chamber cover 23 is opened, and then returns to #1.

FIG. 4 shows another embodiment in which the flowchart in FIG. 1 is partially modified, and steps that are the same as those in FIG. 1 are given the same step numbers and their explanations will be omitted.

As described above, in the camera of this embodiment, first, the fork 20 rotates the supply spool of the film cartridge to push out the leading edge of the film from inside the cartridge, and then the leading edge of the film is attached to the film take-up spool 15 of the camera. Once wrapped, the film is wound onto the film take-up spool 15 at a faster speed than the fork 20.

Therefore, it is possible to detect that the leading edge of the film is wrapped around the take-up spool 15 of the camera by increasing the film feeding speed.

In view of this, in the flowchart of FIG. 4, when the first frame is detected in #11, the process proceeds to #101, and the rotational speed of the disk 3 is determined based on the barcode signal detected by the barcode encoder circuit 36. It is determined whether or not the speed has become faster than a predetermined speed. If the speed has become faster, it is assumed that the film has been wound around the take-up spool 15 of the camera and the process proceeds to #12. If the speed has not become faster, it is determined that the film has been wound around the spool 15 properly. It is determined that the process does not fail and loose winding has occurred, and the process proceeds to #102, where an AL failure display similar to #8 is displayed. Winding is stopped at #103 and the process proceeds to #20.

FIG. 6 shows still another embodiment in which the flowchart of FIG. 1 is partially modified. Steps that are the same as those in FIG. 1 are given the same step numbers, and their explanations will be omitted.

In this embodiment, timer 1 is activated at #201.
, starts timer 2. Timer 1 is shown in Figure 1.
This is the same as the timer. At #202, it is determined whether or not the timer 1 has finished counting the predetermined time, and the same process as #6 in FIG. 1 is performed. At #203, the timer is reset in the same way as #9 in FIG.

#204 if the first frame is not detected in #11
It is determined whether or not the timer 2 has finished counting the predetermined time. If the process has not finished, the process returns to #4, and if it has finished, the process proceeds to #205.

The predetermined time measured by the timer 2 is set to be slightly longer than the time expected from the start of film extrusion to the first frame. #
At 205, AL failure is displayed in the same way as #8 in Fig. 1.
Proceed to 206.

At #206, winding is stopped in the same way as #7 in FIG. 1, and the process proceeds to #20. This occurs when the leading edge of the film does not come out of the cartridge even though the fork 20 is rotating, or when the fork 20 continues to rotate even though the leading edge of the film is caught inside the camera, causing the film to break inside the cartridge. This makes it possible to determine that AL has failed in such a case.

In the above embodiment, the photoreflector 19 and the barcode encoder circuit 36 correspond to the rotation detection means of the present invention, the fork 20 and the motor control circuit 38 correspond to the film extrusion means of the present invention, and the microcomputer 31 corresponds to the determining means of the present invention, but it goes without saying that the present invention is not limited to these embodiments and may be of any type as long as it has a similar function.

[0034]

[Effects of the Invention] As explained above, according to the present invention, in a camera using an extrusion type film cartridge,
If the extrusion of the film fails, the situation can be quickly detected, so damage to the film and damage to the fork drive system can be prevented, making it extremely effective.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the operation of a microcomputer 31 in FIG. 3.

FIG. 2 is a rear view of a camera according to an embodiment of the present invention.

FIG. 3 is a circuit block diagram showing the circuit of the camera in FIG. 2;

FIG. 4 is a flowchart showing other operations of the microcomputer 31 in FIG. 3;

FIG. 5 is a flowchart showing still another operation of the microcomputer 31 in FIG. 3;

FIG. 6 is a perspective view of a push-out film cartridge used in the camera of FIG. 2;

FIG. 7 is a top view of the film cartridge of FIG. 6;

[Explanation of symbols]

1 Film cartridge 15 Film take-up spool 17 Photo reflector 19 Photo reflector 22 pin 32 Release switch 33 Cartridge chamber cover switch

Claims (1)

[Claims] [Claim 1] An information code regarding the film is provided,
In a camera using a push-out film cartridge having a cord member that rotates integrally with a film supply spool, a rotation detecting means for detecting a rotational state of the cord member from an information code of the cord member; A film extrusion means for automatically extruding the film from the cartridge after the film cartridge is loaded, and the rotation detecting means cannot detect the rotation even after a predetermined period of time has elapsed after the film extrusion operation started to extrude the film by the film extrusion means. and determining means for determining that extrusion has failed if