JPH0915680A - Consecutive photographic camera - Google Patents

Abstract

PURPOSE: To accurately execute next consecutive photographing without being effected by the positional fluctuation of a sensor gear even in the case the slight positional fluctuation is caused in the sensor gear by providing the sensor gear, a detection means and a motor control means. CONSTITUTION: Assuming that a stepping motor 3 has a rotation range equivalent to 10 driving pulses for a detection period from the time when a PI signal is obtained from a PI sensor 32 till the time when the PI signal is not obtained, the driving of the motor 3 is stopped when the counted value by a counter attains '5', whereby the rotation of the sensor gear 30 is stopped in a state where the center of the width of the slit 30a is positioned between the light projecting part and the light receiving part of the sensor 32 and the gear 30 is set to an initial position. Thus, even if the gear 30 is rotated in any direction by five driving pulses, it is not out of the detection range of the PI signal. Therefore, when processing for detecting the initial position is performed before the next consecutive photographing, the PI signal is immediately obtained at the specified judging time point, and the camera is instantaneously shifted to a consecutive photographing sequence.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous shooting camera in which a plurality of frames are sequentially shot at short time intervals by one shutter release operation.

[0002]

2. Description of the Related Art A continuous shooting camera known by Japanese Patent Application Laid-Open No. 4-269729 or "Caldia View" (trade name) provided by the present applicant has two slits each serving as a shutter opening. The two formed shutter discs are used, and when one shutter release operation is performed, the shutter discs are simultaneously rotated once by driving the stepping motor. During this rotation, each slit sequentially traverses eight horizontally aligned exposure openings for about 1 to 3 seconds, and an exposure of eight frames is performed through a photographing lens provided in front of each exposure opening. Done. By this single continuous shooting, 8 continuous shooting frames horizontally arranged in 2 frames of 35 mm full size are obtained, and at the exposure position, the upper and lower parts of the film of 2 frames correspond to the panoramic size screen. Since it is masked, it is possible to obtain two panoramic prints with four continuous frames printed on each print.

This continuous shooting camera can be conveniently used, for example, when analyzing the form of a golf swing, but attempts have been made to further increase the number of continuous shooting frames so that more sophisticated analysis can be performed. . For example, in the continuous shooting camera proposed in Japanese Patent Application No. 6-165877 by the applicant of the present invention, a high-definition size film of 2 frames is
A total of 16 frames of continuous shooting will be performed, with 8 shots in each of the upper and lower rows. This 16-frame continuous shooting camera uses eight shutter discs each having one slit and two stepping motors. One stepping motor drives four shutter discs. Has become.

FIG. 6 is an exploded view of an example of a shutter unit for a 16-frame continuous shooting camera, and FIG. 7 schematically shows an arrangement of shutter disks as seen from the front side. The shutter unit accommodates the case 8 in which the stepping motors 3 and 4 and the finder lens are fixed, the gear train and the pair of shielding plates 5 and 6 are incorporated, and eight shutter discs 10 to 17 and 8 A partition plate 20 having 16 exposure apertures 18 arranged in two rows and 16 aperture windows corresponding to the exposure apertures 18 are provided, and a taking lens 21 is provided in front of each of the aperture windows. And a front plate 22 to be assembled.

As shown in FIG. 7, the shutter disks 10 to 10 are arranged.
Slits 10a to 17a are formed in each of 17,
The exposure is performed when the exposure aperture 18 having a constant aperture diameter is traversed. The set of shutter discs 10, 11, 14, 15 and the set of shutter discs 12, 13, 16, 17 are arranged symmetrically, and are driven by stepping motors 3, 4 for each block.

Spindle gear 3 of stepping motor 3
a meshes with a large-diameter gear of the drive gear 24, a small-diameter gear of the drive gear 24 meshes with an outer peripheral gear formed on the peripheral edges of the shutter discs 14 and 15, and further the outer peripheral gears of the shutter discs 14 and 15 have shutter discs. The outer gears 10 and 11 mesh with each other. The shield plate drive gear 25 is further meshed with the small diameter gear of the drive gear 24. A drive pin 25a is planted in the shield plate drive gear 25 and is engaged with the shield plate 6 on the right block side. Shutter discs 10, 11, 1
The outer peripheral gears 4 and 15 all have the same number of teeth, and the blocks on the right side have the same structure from the stepping motor 4 to the shutter disks 12, 13, 16 and 17.

When the shutter release is performed, the stepping motor 3 is driven first, and the shutter discs 10, 11, 1 are driven.
4, 15 rotate once in the direction of the arrow. In the meantime, the slit 10a of the shutter disk 10 keeps the lower exposure opening 1 shown in FIG.
When crossing 8, the second opening and closing are sequentially performed from the left side, and subsequently the slit 11a of the shutter disk 11 opens and closes the third and fourth exposure openings 18 from the left side to perform continuous shooting for four frames. At this time, the shutter disks 14 and 15 also make one rotation, and the slits 14a and 15a open and close the upper exposure opening 18 by four in order from the left side, but since the shielding plate 5 closes the upper exposure opening 18. No exposure is done.

The shutter disks 10, 11, 14, and 15 are 1
The stepping motor 3 is stopped at the time of rotation,
At the same time or immediately before the stop, the stepping motor 4 starts driving, and the exposure is performed by the right block. The shutter disk 1 is driven by driving the stepping motor 4.
When 2 and 13 rotate once, the slits 12a and 13a cross the 5th to 8th exposure openings 18 from the left side of the lower stage, and four frames are continuously shot. During this time, the slits of the shutter disks 16 and 17 open and close the upper exposure opening 18, but at this time, the shield plate drive gear 25 is at a position half-rotated from the position shown in the figure, and the shield plate 6 causes the upper right side four shutters to move. The exposure opening 18 is closed.

The shutter disks 12, 13, 16 and 17 are
When it rotates, the stepping motor 4 is stopped, but the driving of the stepping motor 3 is restarted immediately before that, and the shutter disks 14 and 15 rotate once. And slit 14
The exposure openings 18 on the upper stage are opened and closed up to a fourth opening from the left by a and 15a, and exposure for four frames is further performed. At this time, since the lower exposure opening 18 is closed by the shield plate 5, the shutter disks 10, 11 are closed.
The slit does not expose. Subsequently, the stepping motor 4 restarts driving, and the shutter disk 1
The continuous rotation of the remaining 4 frames is performed by one rotation of 6 and 17.
When one continuous shooting sequence is completed in this way, 16 continuous shooting frames 26 are exposed on the film F in two frames of high-definition size (36 mm × 20 mm).

By the way, since such continuous shooting mostly targets a moving subject, a shorter exposure time is preferable. However, simply increasing the rotation speed of the shutter disc shortens the continuous shooting period from the first frame to the 16th frame. For example, when a golf swing is targeted, a series of movements from the start of the downswing to the follow-through. The problem arises that the image cannot be stored within the continuous shooting period. Under these circumstances, the drive programs for the stepping motors 3 and 4 have been devised so that the speed of the shutter disk is increased at the moment when each slit crosses the exposure opening 18, and the slit has finished passing through the exposure opening 18. The speed of the shutter disk is kept low during the movement to the next exposure opening.

By setting the drive programs for the stepping motors 3 and 4 as described above, it is possible to shorten the exposure time and secure a sufficient continuous shooting period. In order to make the most of it, it is necessary to accurately synchronize the rotation of the shutter disk and the drive program of the stepping motor. Therefore, when the driving of the stepping motors 3 and 4 is started, it is confirmed by using a photo interrupter (hereinafter referred to as PI sensor) whether or not the shutter mechanism portion including the shutter disk is at the initial position as set. I am trying.

In order to confirm the initial position, as shown in FIG. 7 or 8, the small diameter gear of the drive gear 24 is further meshed with the large diameter gear of the interlocking gear 28, and the interlocking gear 2
The sensor gear 30 is meshed with the small diameter gear of 8. The sensor gear 30 is formed with a slit 30a having a constant slit width as a through hole that allows light to pass therethrough. The rotation ratio of the sensor gear 30 is set so that it makes exactly one rotation when the stepping motor 3 rotates by a rotation amount that rotates the shutter disk of the left block twice.

A PI sensor 32 is provided so as to sandwich the sensor gear 30 from the front and back, and the sensor gear 30 rotates between a light projecting portion and a light receiving portion of the PI sensor 32. The PI sensor 32 outputs a PI signal when the slit 30a of the sensor gear 30 is located between the light projecting section and the light receiving section. When the slit 30a is detected by the PI sensor 32 in the initial state as shown in FIGS. 7 and 8, one rotation of the sensor gear 30 is detected by the PI sensor 32 after continuous shooting. The drive of the stepping motor 3 may be stopped at this time.

Then, as shown in FIG. 9, by starting the driving of the stepping motor 3 after confirming the presence or absence of the PI signal at the start of the continuous shooting, the rotation of the shutter disk and the driving program of the stepping motor are set. It becomes possible to synchronize correctly. When the PI signal is not detected in step 1 (ST1) of this initial position detection processing, the stepping motor 3 is driven until the PI signal is obtained in ST2. The same can be said for the shutter mechanism of the right block after the stepping motor 4.

[0015]

However, if the driving of the stepping motor 3 is stopped when the PI signal is detected by the PI sensor 32 as described above, the following problems are likely to occur. The PI sensor 32 has a slit 30a
The PI signal is output at the moment when the light incident on the light receiving section through the light sensor reaches the threshold level. In most cases, as shown in FIG. 10, the light receiving section 32a of the PI sensor 32 is
Is partially exposed from the slit 30a of the sensor gear 30, the PI signal is output, and the driving of the stepping motor 3 is stopped at this point.
Rotation also stops.

However, in particular, as shown in FIG. 7, the drive gear 2 is provided between the stepping motor 3 and the sensor gear 30.
4. Since the reduction gear train including the interlocking gear 28 is provided, the sensor gear 30 tends to reverse in the direction shown by the broken line in FIG. 10 due to the backlash of the meshing portion of the gear. If external vibration is applied to the camera body after photographing, this tendency is further promoted, and the sensor gear 30 often returns to a position where the PI signal cannot be obtained from the PI sensor 32. Then, when the initial position detection process shown in FIG. 9 is performed at the start of shooting, the PI signal detection fails in most cases, and the timing of the start of shooting is missed for the subsequent initial position setting process. It could be done.
It should be noted that such an adverse effect similarly appears even if the threshold level is set to a high level, and cannot be solved at all.

The present invention has been made in consideration of the above circumstances, and accurately detects the end of the continuous shooting sequence based on the position of the sensor gear, and also causes a slight backlash to the sensor gear or vibration from the outside. An object of the present invention is to provide a continuous shooting camera in which the next continuous shooting is correctly executed without being affected by the position change even if the position change occurs.

[0018]

In order to achieve the above object, the present invention has a width in the rotation direction of a sensor gear that makes an integer rotation of one to several times during one continuous shooting. A signal unit is provided, and the movement of the signal unit is detected by the detection means. The detection means detects the signal portion immediately before the sensor gear rotates an integral number of times and outputs the detection signal, but after the detection signal is obtained, the motor control means drives the motor by a fixed angle determined according to the width of the signal portion. It is designed to stop after rotating.

The motor control means further confirms the presence or absence of the detection signal in response to the shutter release operation, and when the output thereof is detected, the motor control means starts driving to execute the continuous shooting sequence and the shutter disc. To drive. When the shutter disk is driven, the motor control means sequentially switches the rotation speed according to the rotation angle of the motor, and the shutter disk is rotated at a high speed during the photographing by the slit. Further, by using the light transmitting portion formed on the sensor gear as the signal portion and using the photo interrupter as the detecting means, the detection signal can be obtained without being in contact with the sensor gear.

[0020]

With the use of the signal portion having a width in the rotation direction of the sensor gear, the detection signal is obtained just before the sensor gear makes an integral rotation, and thereafter the motor gear is rotated by a fixed angle determined according to the width of the signal portion. Therefore, even if the sensor gear reverses and returns within the range of the predetermined angle or less due to the gear backlash or the like, the signal section is detected by the detecting means.
As a result, it is not necessary to rotate the motor unnecessarily to set the sensor gear to the initial position, and it is possible to quickly and accurately manage the continuous shooting sequence.

[0021]

FIG. 2 shows the appearance of a continuous shooting camera using the present invention. A shutter unit shown in FIG. 6 is incorporated in the camera body 35, and the mechanical structure is common to those shown in FIGS. 7 and 8. Photographing lenses 21 assembled on the front plate 22 by arranging them in two stages of eight each are exposed one by one from the 16 photographing windows on the front surface of the camera body, and each photographing is performed by rotating the shutter disks 10 to 16. 16 frames can be continuously shot through the lens 21.
On the upper surface of the camera body, a power switch knob 36, a shutter button 37 for one frame, a shutter button 38 for continuous shooting, a continuous shooting speed switching knob 39, and a liquid crystal display panel 40.
Is provided.

FIG. 3 shows a functional block diagram of the continuous shooting camera. The CPU 42 controls the shooting sequence of the entire continuous shooting camera according to the sequence program stored in the program ROM area 43a of the memory 43. A program for driving the stepping motors 3 and 4 is also stored in the program ROM area 43a, and the rotation speed of the stepping motors 3 and 4 after the continuous shooting sequence is started is thereby controlled. In the RAM area 43b, data, flags and the like that are appropriately obtained before or during the execution of the shooting sequence are appropriately written and read. Further, in the EEPROM area 43c, various data adjusted at the manufacturing stage of the continuous shooting camera, for example, as will be described later in detail, one shooting sequence is completed and PI
After the signal is obtained, the number of drive pulses for determining how many drive pulses the stepping motors 3 and 4 should be driven before stopping is written. The programs and data written in the program ROM area 43a and the EEPROM area 43c together with the CPU 42 constitute motor control means for controlling the driving and stopping of the stepping motors 3, 4.

The release signal generating circuit 44 is set to 1 depending on which one of the shutter button 37 for one frame and the shutter button 38 for continuous shooting is pressed by the shutter release operation.
CP for either the frame release signal or the continuous shooting release signal
Input in U42. The continuous shooting speed setting circuit 45 inputs a speed switching signal corresponding to the set position of the continuous shooting speed switching knob 39 to the CPU 42. By this speed switching signal, the overall driving speed of the stepping motors 3 and 4 is switched between “Hi”, “Normal”, and “Lo”, and the continuous shooting period during 16-frame continuous shooting is 1 second or 2 seconds.
Second or 3 seconds is selected.

The one-frame shooting counter 46 counts the number of frames when one frame is shot before continuous shooting by operating the one-frame shutter button 37. The frame counter 47 counts the number of frames of the photographed film. In this continuous shooting camera, when 16 frames are shot in one shooting sequence, two frames of the film are consumed, and therefore each time the film is fed, it is incremented by "2". The count values of these counters 46 and 47 are displayed on the liquid crystal display panel 40. The film feeding mechanism 48 includes a winding motor and feeds two frames of the film when one photographing sequence is completed.

The driver 50 receives the drive pulse supplied from the CPU 42 and drives the stepping motor 3. The drive pulse supplied to the driver 50 is the counter 5
The count value is 1, and the count value is sequentially fed back to the CPU 42. The reset terminal of the counter 51 has P
The PI signal from the I sensor 32 is input. The PI sensor 32 is used as a detection unit that detects that the sensor gear 30 has rotated once as described above, and the PI signal is used as the detection signal. PI signal is counter 5
When input to the reset terminal of 1, the count value is "0"
Is cleared. In addition, the CPU 4 is connected to this reset terminal.
The reset signal can also be input from 2. Also,
Driver 52 and counter 5 on the stepping motor 4 side
The 3, PI sensor 54 also performs exactly the same operation.

The power switch 55 is the power switch knob 3
It is turned on by the operation of 6, and power is supplied from the power battery 56 built in the camera body 35 to appropriate circuit loads such as the CPU 42, the film feeding mechanism 48, the drivers 50 and 52.

FIG. 4 shows how the shutter disk is driven when 16 frames of continuous shooting are performed with the continuous shooting period set to 2 seconds. The horizontal axis represents the elapsed time, the vertical axis represents the rotation angle of the shutter disk, and the solid line represents the rotation of the shutter disks 10, 11, 14, 15 belonging to the block on the left side of FIG. 7 (stepping motor 3
7), and the broken lines show the rotation (by driving of the stepping motor 4) of the shutter disks 12, 13, 16, 17 belonging to the block on the right side of FIG. Note that when the continuous shooting period is set to 1 second or 3 seconds, the time axis shown in FIG. 4 is simply shortened and extended, and the drive pattern of the shutter disk remains unchanged.

By rotating the shutter discs exactly twice, one continuous shooting sequence is completed. Then, each time a slit passes through the exposure opening 18 each time it passes through the exposure position represented by two chain lines in the drawing during the rotation, exposure for one frame (Ex1, Ex2, Ex2, Ex2, Ex2) is performed. ··· Ex16) is sequentially performed. Immediately after the continuous shooting is started and immediately before the continuous shooting is finished, the exposure interval between the next exposures is wide, which means that the motion of the moving subject is gentle at the beginning and end of the motion. Because. Further, the exposure time during the actual exposure is such that the rotation speed of the shutter disk is faster than the exposure period, so that the motion of the moving subject can be momentarily stopped and the image can be taken.

Such a drive pattern for the shutter disk can be realized by deciding a drive program for the stepping motors 3, 4. The rotational positions of the stepping motors 3 and 4 are the number of drive pulses input for driving,
The rotation speed can be changed by the frequency of the drive pulse. Therefore, the frequency switching data is prepared in the program ROM area 43a in association with the count value of the drive pulses counted by the counters 51 and 53, and after the stepping motors 3 and 4 are driven, the counter 5
The frequency of the drive pulse output from the CPU 42 may be switched each time 1, 53 reaches a predetermined count value.

When the shutter button 37 for one frame is operated to expose only the first frame (Ex1) and to continuously shoot the 15 frames after the exposure (Ex2) of the second frame,
Alternatively, the drive program for the case where the shutter button 37 for one frame is pressed several times to perform one frame shooting several times, and then the continuous shooting is performed for the remaining frames, should be separately stored in the program ROM area 43a. Good.

The operation of the above continuous shooting camera using the present invention is as follows. When the shutter button 38 for continuous shooting is pressed after turning on the power switch knob 36, the initial position confirmation program prepared in the program ROM area 43a is executed. The initial position confirmation processing executed by this is as shown in FIG. 1, and is different from the conventional initial position confirmation processing shown in FIG. With the start of the initial position confirmation processing, the CPU 42 confirms whether or not the PI signals are output from the PI sensors 32 and 54 in the determination processing of step 10 (ST10).

When the PI signal is confirmed in ST10, the initial position confirmation process is completed, and the regular drive programs for the stepping motors 3 and 4 are executed.
Shutter disks 10 to 1 according to the drive pattern shown in FIG.
6 is driven, and continuous shooting of 16 frames is sequentially performed.
In the above initial position confirmation processing before the start of shooting, ST10
If at least one of the PI signals cannot be confirmed in step 2, the CPU 42 supplies a low-frequency drive pulse to the corresponding stepping motor to perform pre-driving. The drive pulses input to the drivers 50 and 52 during this preliminary drive are counters 51 and 53 by the processing of “N ← 0”.
Will not be counted.

While the pre-driving is being carried out, if the detection of the PI signal is confirmed by the judgment at ST11, the initial position adjusting driving of the stepping motors 3 and 4 is carried out from that point. In the initial position adjustment drive processing, the number of drive pulses input from the CPU 42 to the drivers 50 and 52 is counted by the respective counters 51 and 53. And the counter 5
ST1 indicates that the count value of 1,53 has reached a constant value K.
When the result is confirmed in 2, the driving of the stepping motors 3 and 4 is stopped, the count values of the counters 51 and 53 are cleared to "0", and the initial position detection processing is ended.

The value of the constant value K is determined as follows according to the slit width of the slit 30a of the sensor gear 30. When the sensor gear 30 is rotated by the driving of the stepping motor 3, its slit 30a is PI
A PI signal is obtained when the sensor 32 passes between the light emitting and receiving portions, and the PI signal is continuously obtained while the stepping motor 3 rotates by a certain angle. That is, the PI signal detection period ΔT is determined by the slit width of the slit 30a and the unit step angle (rotation angle per drive pulse) of the stepping motor 3, and the PI signal detection period ΔT is replaced by the number of drive pulses. be able to.

For example, this detection period ΔT is the drive pulse 1
When the number corresponds to 0, the value of the constant value K is 1
It is set to "5" which corresponds to / 2. When the initial position detection process shown in FIG. 1 is completed in this way, the stepping motors 3 and 4 are driven according to the normal continuous shooting sequence as described above, and the shutter disk operates in the drive pattern of FIG. Is done.

After the 16-frame continuous shooting is started in this way, C
The PU 42 monitors whether or not the PI signal is detected by the PI sensors 32 and 54, and performs the initial position detection process shown in FIG. 1 again. After the 16-frame continuous shooting sequence is started once, the PI signal is not detected until the 16-frame continuous shooting sequence is completed. You may perform an initial position detection process immediately after 4 rotates.

FIG. 5 is a timing chart showing the operation when the initial position detection process is performed on the stepping motor 3 after the 16-frame continuous shooting is completed, which is also common to the other stepping motor 4. CPU
Every time one driving pulse is input from 42 to the driver 50, the driver 50 outputs exciting pulses φ1 and φ2 whose phases are shifted by half a wavelength and exciting pulses (not shown) having a phase opposite to those of the exciting pulses φ1 and φ2. Input to the stepping motor 3. As a result, the stepping motor 3 is continuously driven even after the 16-frame continuous shooting.

By driving the stepping motor 3 in this way, the sensor gear 30 also continues to rotate, but when the slit 30a reaches the position detected by the PI sensor 32, the output signal from the PI sensor 32 is output. The level drops from high level (H) to low level (L), and this L signal is input to the CPU 42 as a PI signal. Conventionally, the supply of the drive pulse from the CPU 42 is cut off at this timing and the stepping motor 3 is stopped. However, the CPU 42 continues to output the drive pulse to the driver 50 by the processing of FIG.

When the PI signal is obtained, the CPU 42 clears the count value of the counter 51 to "0", and the drive pulse supplied to the driver 50 thereafter is counted by the counter 51. Then, when the count value reaches a constant value K, which is "5" in the illustrated example, the output of the drive pulse is cut off and the stepping motor 3 is stopped.

As described above, from the PI sensor 32 to the PI
Assuming that the stepping motor 3 has a rotation range of 10 drive pulses during the detection period ΔT from the time when the signal is obtained to the time when the PI signal is not obtained, the count value of the counter 51 is " When the driving force of the stepping motor 3 is stopped at the time when the number reaches 5 ", the center of the slit width of the slit 30a is approximately equal to the PI sensor 32.
The rotation of the sensor gear 30 is also stopped in a state in which the sensor gear 30 is positioned between the light emitting and receiving portions, and this is the initial position of the sensor gear 30. In FIG. 5, drive pulses and other waveforms when the stepping motor 3 is continuously driven are shown by broken lines to represent the detection period ΔT.

By performing the above-described processing to set the initial position of the sensor gear 30 after the continuous shooting sequence, it is assumed that the sensor gear 30 may rotate in any direction by five drive pulses. Also,
It does not deviate from the detection range of the PI signal. Therefore, when the initial position detection processing of FIG. 1 is executed prior to the next continuous shooting, PI is immediately determined at the time of determination in ST10.
A signal can be obtained, and it is possible to immediately shift to the continuous shooting sequence. The number of drive pulses corresponding to the detection period ΔT is confirmed in the manufacturing stage, and the value of the constant value K is determined based on this, and the constant value K thus determined is stored in the memory 43 at that time.
It is written in the EPROM area 43c.

By the way, when the slit width of the slit 30a is made too large, the detection period ΔT becomes long accordingly, and the initial position of the sensor gear 30 has a great degree of freedom. Then, in the initial position detection process performed immediately before the start of the shooting sequence, the PI signal detection will not fail in ST10. However, the increase in the detection period ΔT means that the degree of freedom also appears in the initial position of the shutter disc meshed with the drive gear 24.

Therefore, if the detection period ΔT becomes too large, if the PI signal is immediately detected in ST10 of the initial position detection process before the start of photographing, the shutter disk exceeds the allowable range from the normal initial position. Slipped off,
A slit formed in the shutter disk as an opening for opening and closing the shutter may partially overlap the exposure opening 18. As shown in FIG. 7, each shutter disk 10
Since the slits 10a to 17a formed in .about.16 are the normal initial positions at positions close to the exposure opening 18, if the shutter disks 10 to 17 are deviated from the normal initial positions to some extent, the shutter disks are made. However, even if the film is exposed before the rotation starts, or even if the shutter disk is rotated according to the drive program of FIG. 4, proper exposure time and exposure interval cannot be maintained.

Under these circumstances, the detection period ΔT has a proper range so that the slit of the shutter disk does not overlap the exposure opening 18 at least at the start point and the end point of the detection period ΔT, and the sensor gear 30 has a gear backlash. The detection period ΔT is greater than the angle range moved by
It is better to secure as. Further, as the value of the constant value K, in consideration of the possibility that the sensor gear 30 may be rotationally deviated in both directions from the normal initial position, the detection period Δ
When the number of drive pulses corresponding to T is N, “N
It is better to set it to "/ 2". Of course, if only the gear backlash is taken into consideration, for example, in the case of the above embodiment, it is possible to set the constant value K to "5" and narrow the detection period ΔT to five drive pulses.

The present invention has been described above based on the illustrated embodiment, but the number of revolutions of the sensor gear 30 is not necessarily limited to one revolution, and the shutter disc is continuously photographed once. It suffices that the rotation is set to an integral number of rotations from the normal initial position and stopped when the rotation necessary for the sequence is performed. In this case, the output number of the PI signal may be counted by the counter, and the same processing may be performed with the PI signal of the integer rotation. Further, the present invention is not limited to the number of shutter disks or the number of frames for continuous shooting as long as continuous shooting is performed by rotating the shutter disk. It is equally applicable to those who make copies.

Further, in order to detect that the sensor gear 30 has rotated to the initial position, a reflection piece fixed to the sensor gear 30 is used as a signal portion, and this is detected by a reflection type photo sensor, and further, a conductor piece. The rotation of the sensor gear 30 can be detected by a sliding contact piece, a combination of a magnetic material and a Hall element, or the like. Also, instead of driving the shutter disk with a stepping motor, a precision DC motor is used, and the encode plate is fixed to the spindle to obtain a large number of encode pulses per rotation, and this encode pulse is the same as the drive pulse described above. It is also possible to count and perform various controls.

[0047]

As described above, according to the present invention, a signal portion is provided in a sensor gear which rotates an integer while one continuous shooting sequence is performed, and this signal portion is detected immediately before the sensor gear rotates an integer number of times. However, after the detection, the shutter disk and the motor for driving the sensor gear are rotated by a certain angle according to the width of the signal part and then stopped, so that the sensor gear may be stopped by external vibration or gear backlash. Even if the rotational position is slightly deviated from the regular initial position, the detection unit can detect the signal portion. Therefore, it is possible to accurately manage the continuous shooting sequence without taking the time to detect the initial position of the sensor gear and losing the shooting timing at the start of the continuous shooting sequence.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an initial position detection process performed by the present invention.

FIG. 2 is an external view of a continuous shooting camera using the present invention.

FIG. 3 is a functional block diagram showing an outline of an electrical configuration of a continuous shooting camera.

FIG. 4 is a timing chart showing an example of a shutter disk drive program.

FIG. 5 is a timing chart explaining the operation of the present invention.

FIG. 6 is an exploded perspective view of a shutter unit used in a continuous shooting camera.

FIG. 7 is a schematic view of a shutter mechanism from a stepping motor to a shutter disc.

FIG. 8 is a perspective view showing a structure around a sensor gear.

FIG. 9 is a flowchart showing a conventional initial position detection process.

FIG. 10 is an explanatory diagram showing a stop position of a sensor gear according to conventional control.

[Explanation of symbols]

 3,4 Stepping motor 10-17 Shutter disk 10a-17a Slit 18 Exposure opening 30 Sensor gear 30a Slit 32 PI sensor 42 CPU 51, 53 Counter 43 Memory

Claims (3)

[Claims] 1. Continuous shooting in which a plurality of continuous shooting frames are sequentially shot through a shutter opening formed in the shutter disk by driving a motor in response to a shutter release operation. In the camera, a sensor gear that is rotated in an integral number while the shutter disk rotates by an angle necessary to complete one continuous shooting sequence, and a signal formed on the sensor gear with a certain width in the rotation direction. Detecting means for outputting a detection signal immediately before the sensor gear makes an integral rotation of the sensor gear, and after the detection signal is obtained, the motor is rotated by a certain rotation angle determined according to the width of the signal portion. A continuous shooting camera, comprising: a motor control unit that stops the motor after the operation. 2. The motor control means drives the motor to execute a continuous shooting sequence when a detection signal is obtained from the detection means in response to a shutter release operation, and while the continuous shooting sequence is being executed. 2. The continuous shooting camera according to claim 1, wherein the rotation speed is sequentially switched according to the rotation angle of the motor, and the shutter disk is rotated at a high speed while photographing is performed by the shutter opening. 3. The continuous shooting according to claim 1, wherein the signal portion is a light transmitting portion formed on a sensor gear, and the detecting means is a photo interrupter for photoelectrically detecting the light transmitting portion. camera.