JPH03167537A - Device for feeding film of camera - Google Patents

Abstract

PURPOSE:To surely judge that a film leader part is wound around a take-up spool by providing a means which receives a signal from moving speed detecting means in response to a moving speed, discriminates whether or not the moving speed of a film is changed and outputs a discrimination signal. CONSTITUTION:A device is provided with a means feeding the film leader part from a film cartridge at prescribed speed and a means taking up the film leader part around the take-up spool at the speed higher than the prescribed speed. At this time, the leader part of the film 3 is wound around the film take-up spool 2, whereby its moving speed is changed. In response to this change, the signal outputted from the moving speed detecting means is changed. The discriminating means discriminates this change of the signal and outputs the discrimination signal showing that the moving speed of the leader part of the film 3 is changed. Thus, it is easily detected that the leader part of the film 3 is wound around the film take-up spool 2.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a film feeding device for a camera. [Prior art 1] As a film cartridge (lower D, referred to as a cartridge) loaded into a camera, USP. 48343oc has been proposed. This cartridge is constructed horizontally so that the film stored inside the cartridge can be sent out by rotating the shaft of the cartridge.

[Problem to be Solved by the Invention 1] In a camera using the above-mentioned cartridge, the camera rotates the shaft of the cartridge to feed out the leader portion of the film stored in the cartridge, and the film leader is placed on the film take-up spool. You will have to wrap up the parts. However, conventionally, in such cameras, it has not been possible to detect that the film has been wound around the film take-up spool.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a film feeding means for feeding out a film leader section at a predetermined speed from a film cartridge loaded in a camera, and a film winding means for automatically winding the leader portion of the film onto the take-up spool at a speed higher than the predetermined speed; and a moving speed for outputting a signal corresponding to the film moving speed. It has a detecting means, and a determining means that receives a signal corresponding to the moving speed from the moving speed detecting means, determines whether or not there is a change in the moving speed of the film, and outputs a determining signal.

Further, the moving speed detecting means may output a signal corresponding to the moving speed of the film itself. Further, the moving speed detecting means outputs a signal corresponding to the rotational speed of the take-up spool that winds the leader portion of the film, and the discriminating means receives a signal corresponding to the rotational speed from the moving speed detecting means. , a determination signal may be output by determining whether or not there has been a change in the rotational speed of the take-up spool. Furthermore, a clutch means may be provided to connect the film feeding means and a motor for driving the film feeding means, and the clutch means may be disconnected in response to a discrimination signal outputted from the discrimination means.

[Operation 1: The leader portion of the film fed from the film cartridge is automatically wound onto the take-up spool. When the leader portion of the film is wound around the film take-up spool, the moving speed of the leader portion of the film changes, and in accordance with this change, the signal output from the moving speed detecting means changes. The determining means that determines the change in this signal outputs a determination signal indicating that there has been a change in the moving speed of the film leader section. Therefore, it can be reliably determined that the film leader section has been wound around the take-up spool.

[Example] Next, this invention will be explained with reference to the drawings. FIG. 1 is a perspective view showing a first embodiment of a film feeding device for a camera according to the present invention, and FIG. 2 is a circuit diagram of the same embodiment.

In FIG. 1, the film cartridge 1 is placed horizontally so that the film 3 is fed out by rotating the central shaft around which the film is wound from the outside.
The film 3 is fed out by rotating a coupling 6 that engages with the central axis of the cartridge. A well-known gear train (not shown) including a clutch means 5 is interposed between the motor 4 and the coupling 6.
The central shaft of the cartridge l rotates in accordance with the operation of the motor 4 and the gear train. A film take-up spool (hereinafter referred to as a take-up spool) 2 winds up the film 3 that has been sent out to the top of the spool by a motor 7. The photointerrupter 8 is arranged to detect perforation holes in the moving film 3.

As shown in FIG. 2, the photointerrupter 8 is
D 2 1 and a photodiode 22. The pulse generation circuit 23, which is a well-known photoelectric conversion circuit, receives the output signal of the photodiode 22 and outputs a pulse signal Sp synchronized with the movement of the perforation holes in the film 3. These LEDs 21, photodiodes 22, and vanores generation circuits 23 are collectively connected to the pulse output means 2.
Call it 0. The pulse signal Sp output from the pulse output means 20 is input to the CPU 24 and is subjected to processing described later. The CPU 24 controls the aforementioned motor (Mt) 4 and motor (M2) 7 via the motor drive circuit 25. The motor drive circuit 25 drives the motor (Ml) 4 using the drive signal d1, and the motor 7 using the drive signal d2 (M2). FIGS. 3(a) to 3(c) are time charts showing the pulse signal Sp and drive signals d2, dl in this first embodiment, and will be explained together with the explanation of the flowchart in FIG. 4.

First, when it is detected that the cartridge 1 is loaded into the camera, the CPU 24 causes the motor drive circuit 25 to drive the motor 4.
, 7 (step Lot). The loading of the cartridge 1 may be detected by a known method, for example, by detecting that the cartridge 1 is loaded into the camera and the opening/closing cover (back cover) of the cartridge chamber is closed.

When the motor drive circuit 25 receives the drive instruction, it outputs drive signals di and d2 (see FIG. 3(a),
(b) ). The motor 4 operates to feed the film 3 from the cartridge 1 via a gear train (not shown), but the motor 7 merely idles the take-up spool 2 at this point. The film 3 fed out from the force cartridge 1 advances toward the take-up spool 2 and passes through a photointerrupter 8 disposed along its path. As a result, the pulse generating circuit 23 outputs a pulse signal SP having a state (pulse width) as shown in area A of FIG. 3(C). As the film 3 continues to be fed out, the leading edge of the film 3 reaches the take-up spool 2. Here, since the take-up spool 2 is already rotating in the winding direction, the film 3 is wound up by this take-up spool 2. Here, by setting the rotational speed Rl of the take-up spool 2 to be larger than the rotational speed R2 of the central shaft that feeds the film of the cartridge 1 (Rl>R2), as shown in FIG. 3(C), The state of the pulse signal sp changes from region A to region B4. That is, with the transition from area A to area B, the pulse width of pulse signal SP changes to a short state.

Steps 102 to 105 in FIG. 4 are for recognizing the above transition phenomenon.

A pulse signal Sp generated in accordance with the movement of the barfing holes in the film 3 passing through the photointerrupter 8.
(Step 102) and determine its pulse width (Step 103). Compare this determined pulse width with the pulse width of the previous pulse, that is, the previous pulse, and see if there is a change. Determine whether or not there has been a change in the moving speed of the foration hole, and return to step 102 if "N". In other words, there is no change, return to step 102, and "Y" if there is a change, proceed to the next step l.
05 (step 104), it is detected whether the amount of change in pulse width exceeds a predetermined value, and "N" is detected. That is, if it has not been exceeded, the process returns to step 102, and if it is "Y", that is, it has been exceeded, the process proceeds to the next step (step 105).

A value is determined in advance for the amount of change in pulse width accompanying the transition from area A to area B. For example, if the relationship between the moving speed of the film 3 before it is wound on the take-up spool 2 and the movement speed of the film 3 after it is wound on the take-up spool 2 is set to 1:2, then the above A value corresponding to the difference between the two moving speeds is adopted as the predetermined value in step 105 above.

When a transition from area A to area B is detected in the operations of steps 1.02 to 105, a command to stop the motor 4 is sent from the CPU 24 to the motor drive circuit 25, and the motor drive circuit 25 stops the motor 4. The output of the drive signal d1 is stopped (FIG. 3(b)), and the motor 4 is stopped (step 106). When the motor 4 is stopped, the clutch 5 described above operates to disconnect the motor 4 from the coupling 6, thereby preventing the motors 4 and 7 from being subjected to an excessive load on each other.

Even after the motor 4 is stopped, the motor 7 continues to rotate, so the winding spool 2 continues to wind the film. Detection of the perforation holes is continued, and counting of the perforation holes that have passed through is started after the motor 4 is stopped (step l07). This is a so-called operation for empty film feeding, and it is determined whether or not the number of pulses corresponding to the amount of empty feeding of film 3 has been counted (step L08>, "Y", that is, if it has been counted, , the motor 7 is stopped and the winding operation of the film 3 by the take-up spool 2 is completed (step 109); if "N", that is, the count has not been made, the process returns to step 107.

FIG. 5 is a flowchart showing a second embodiment which is an application of the first embodiment explained in FIG.

First, as in FIG. 4, the two motors are started to drive (step 201), and the timer starts timing operation (
Step 202).

Next, it is determined whether there is human power for the pulse signal Sp from the pulse generation stage 20 (step 203), and the loop with step 204 is repeated until the pulse signal SP is input. If the input of the pulse signal Sp is not obtained within the predetermined timer time, the motor 4
．． 7 are both stopped and stop operating (step 20
5〉. This indicates that although an attempt was made to send out the film 3 from the cartridge 1, the film 3 could not pass through the photointerrupter 8 for some reason, and this is a countermeasure against this. In step 203, if the pulse signal Sp is normally input, the time setting of the timer is changed and the timer is restarted (steps 206, 207).
, operations similar to steps 103 to 105 shown in FIG. 4 are performed, and the movement state of the film 3 is monitored (
Step 208. 209>. Here, film 3
As long as there is no change in the moving state of the film 3, the loop including step 211 is repeated, and if no change in the moving state of the film 3 is recognized within the time set in the timer, the driving of the motors 4 and 7 is stopped. to end the operation (step 2
12). In other words, here, although the film 3 was able to pass through the photointerrupter 8, it was detected that the film 3 was not wound normally on the take-up spool 2. This is a countermeasure. Further, after a change in the moving state of the film 3 is detected (step 210), the motor 4 is stopped (step 213), and the same film feeding operation as in steps 107 to 109 in FIG. 4 is performed (step 214). .

FIG. 6 is a perspective view showing the third embodiment, and the same reference numerals as in FIG. 1 indicate the same or corresponding parts, and the explanation thereof will be omitted. Further, FIG. 7 is an elliptic circuit diagram of the same embodiment, and the same reference numerals as in FIG. 2 indicate the same or corresponding parts, and the explanation thereof will be omitted.

In FIG. 6, reference numeral 9 divides a transparent circular plate into a predetermined number of regions in the radial direction, and alternately provides transmissive regions that transmit the light projected from the photointerrupter 10 and opaque regions that do not transmit the light. This encoder plate is provided on the motor shaft of the motor 7.

The photointerrupter 10 detects the rotation state of the motor 7 by detecting the transparent area and non-transparent area according to the rotation of the encoder plate 9.

Although the third embodiment shows that the rotational state of the motor 7 is detected directly from the encoder plate 9 provided on the motor shaft, the present invention is not limited to this; Of course, the rotating state may be detected from the B mechanism provided between the take-up spool 2 and the motor 7.

Furthermore, the movement of the film 3 is detected by the photointerrupter 8, as in the first embodiment.

In FIG. 7, the photointerrupter 10 of FIG.
It is shown by an LED 26a and a photodiode 26b. The pulse generation circuit 26c, which is a well-known photoelectric conversion circuit,
The output signal of the photodiode 26b is input and a pulse signal Sp' synchronized with the rotation of the encoder plate 9 is output.

The LED 26a, photodiode 26b, and pulse generation circuit 26c are collectively referred to as pulse output means 26.

The pulse signal SP' from this pulse output stage 26 is CP
It is input to U24, and the processing described below is performed. FIG. 8 is a time chart showing the second embodiment, and will be explained in conjunction with the explanation of the flowchart shown in FIG. 9.

First, when it is detected that the cartridge 1 is loaded into the camera, the CPU 24 causes the motor drive circuit 25 to drive the motor 4.
, 7 (step 30l). When the motor drive circuit 25 receives this motor drive instruction and outputs drive signals di and d2 (FIGS. 8(a) and 8(b)), the motor 4 operates to feed the film 3 from the cartridge 1. However, the motor 7 only idles the take-up spool 2 at this point. Further, since the encoder plate 9 rotates at the same time as the motor 7 starts rotating, the pulse generating means 26 outputs a pulse signal SP' based on the detection signal of the photointerrupter 10 (FIG. 8(C)). The signal Sp' appears simultaneously with the start of rotation of the motor 7.

On the other hand, the film 3 fed out from above the cartridge advances toward the take-up spool and passes through a photointerrupter 8 disposed along its path.

As a result, the pulse output stage 20 outputs a pulse signal SP as shown in FIG. 8(d). Furthermore, as the film 3 continues to be fed out, the leading edge of the film 3 is attached to the take-up spool 2.
reach. Here, since the take-up spool 2 is already rotating in the winding direction, the film 3 is wound up by this take-up spool 2. Here, by setting the rotation speed R1 of the take-up spool 2 to be larger than the rotation speed R2 of the central shaft that feeds the film of the cartridge 1 (RL>R2>, as shown in FIG. 8(C)
As shown in , the state of the pulse signal SP" transitions from area A to area B. In other words, as the transition from area A to area B occurs, the pulse width of the pulse signal SP changes to a longer state. In other words, when the winding When the film 3 is wound around the spool 2, a load is applied to the take-up spool 2, which had previously been rotating with no load, resulting in a change in the number of revolutions. This is an attempt to determine whether the film 3 is wound around the take-up spool 2 by detecting it.

Steps 302 to 305 are for recognizing the above transition phenomenon.

Step 302): Detect the pulse signal SP' output according to the rotational speed of the motor 7 detected by the photointerrupter 10. The pulse width is determined (Step 3+) 3), and with respect to the determined pulse width, it is determined whether or not there has been a change in the rotational state of the motor 7 compared to the pulse width of the previous pulse, that is, the previous pulse. It is determined whether or not there is a change in the rotation speed of the motor 7. Step 304>, "N". In other words, if there is no change, step 3
Returning to 02, r'y, that is, if there is a change, it is determined whether the detected amount of change in pulse width is greater than or equal to a predetermined value (step 305). Area A in advance
A value is determined for the amount of change in pulse width due to the transition from to region B. That is, the pulse width before the film 3 is wound onto the take-up spool 2, that is, when the motor 7 is rotating under no load, and the pulse width after the film 3 is wound onto the take-up spool 2. In other words, if the pulse width when the motor 7 is rotating under load is set to an appropriate value, a value corresponding to the difference between the two pulse widths will be set as the predetermined value in step 305. It will be adopted. If the result in step 305 is "N", that is, the value is not greater than or equal to the predetermined value, the process returns to step 302, and "
Y”, that is, if the value is greater than the predetermined value, the motor drive circuit 25
stops supplying the drive signal d1 to the motor 4 (see Fig. 8).
b)), motor 4 is stopped (step 308)
．． When the motor 4 is stopped, the clutch means 5 described above operates to disconnect the motor 4 from the coupling 6, thereby preventing the motors 4 and 7 from being subjected to an undue load on each other.

Even after the motor 4 is stopped, the take-up spool 2 continues to take up the film 3, and when the motor 4 is stopped, counting of perflation holes in the film 3 is started (steps 309, 310). As described above, this is an operation for the blank feed, and it is determined whether or not the number of pulses corresponding to the blank feed amount of the film 3 has been counted (step 311>, "Y", that is, a predetermined number of pulses). When the counting is completed, the motor drive circuit 25
The supply of the drive signal d2 to is stopped (FIG. 8(a)),
The winding operation of the film 3 by the take-up spool 2 is completed (step 312), and if "N", that is, the counting of the predetermined number of pulses has not been completed, the process returns to step 309.

In this embodiment described above, separate and independent motors are used for film feeding and film winding, but the present invention is not limited to this, and a single motor may be used for both purposes. Needless to say.

[Effects of the Invention] As explained above, according to the camera film feeding device of the present invention, the moving speed of the film leader changes as the film leader wraps around the film take-up spool. In response to this change, a change occurs in the signal output from the moving speed detection means. The determining means that determines the change in this signal outputs a determination signal indicating that there has been a change in the moving speed of the film leader section. Therefore, it is possible to easily detect that the leader portion of the film is wound around the film take-up spool.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a first embodiment of a film feeding device for a camera according to the present invention, Fig. 2 is a circuit diagram of the same embodiment, and Figs. 3(a) to (C) are the same implementation. A time chart in the example, FIG. 4 is a flow chart in the same example,
Fig. 5 is a flowchart in the second embodiment, Fig. 6 is a perspective view showing the third embodiment, Fig. 7 is a circuit configuration diagram in the same embodiment, and Figs. 8(a) to (d) are the same. A time chart in the embodiment and FIG. 9 is a flowchart in the embodiment. 1...Cartridge, 2...Film take-up spool, 3...Film, 4, 7--Motor, 5...
・Clutch means, 8.10... photo interrupter,
9...1 encoder plate, 20.26-... pulse generating means.

Claims (4)

[Claims] (1) In a film feeding device for a camera that uses a film cartridge configured such that the leader portion of the film stored inside the cartridge is sent out to the outside of the cartridge by rotation of the shaft of the cartridge, loading the film into the camera a film feeding means for feeding out a leader portion of the film from the film cartridge at a predetermined speed; a film winding means for winding the film onto the take-up spool; a moving speed detecting means for outputting a signal corresponding to the moving speed of the film; a signal corresponding to the moving speed from the moving speed detecting means; 1. A film feeding device for a camera, comprising discriminating means for discriminating whether or not there has been a change in speed and outputting a discriminating signal. (2) A film feeding device for a camera according to claim 1, wherein the moving speed detecting means outputs a signal corresponding to the moving speed of the film itself. (3) In claim 1, the moving speed detecting means outputs a signal corresponding to the rotational speed of the take-up spool for winding the film, and the discriminating means detects the rotational speed from the moving speed detecting means. 1. A film feeding device for a camera, which receives a corresponding signal, determines whether or not there is a change in the rotational speed of the take-up spool, and outputs a determination signal. (4) In claim 1, a clutch means is provided for connecting the film feeding means and a motor for driving the film feeding means, and the clutch means is disengaged in response to a discrimination signal outputted from the discrimination means. A camera film feeding device characterized by: