JP6061564B2 - Imaging device having shutter device - Google Patents

Description

  The present invention relates to an imaging device having a shutter device, and more particularly to an imaging device having a shutter device that controls irradiation of a required amount of light to an imaging medium such as a silver salt film and an imaging element.

  Conventionally, in order to simplify the mechanism of a focal plane shutter, there is provided a shutter device having a leading blade composed of a plurality of small single curtains, a trailing blade composed of a plurality of small single curtains, and two electromagnets for controlling opening and closing of each. Has been. For example, in Japanese Patent Laid-Open No. 2006-98909, in addition to the above configuration, a leading blade driving spring for traveling in an exposure window in which a leading blade is provided on a shutter base plate, and an exposure window in which a trailing blade is provided on a shutter base plate. And a charge lever for storing these two springs. Before the start of shooting, the front and rear blades are charged by the charge lever, and the front and rear blades are held as they are. As a preparatory holding state before running, the charge lever leading blade and trailing blade holding is released by retracting the charging lever, energizing the two magnets sequentially, cutting the leading blade and trailing blade sequentially, It is described that the required time is obtained.

JP 2006-98909 A

  However, in the above Japanese Patent Laid-Open No. 2006-98909, even when the shutter release operation is performed on the image pickup apparatus as described above, the shutter remains in a state in which it cannot travel if the charge lever is kept in contact with the member to be charged. Therefore, a process of driving the charge motor and retracting the charge lever from the member to be charged becomes necessary before the shutter starts traveling. As a result, it takes a time from several tens of milliseconds to several hundreds of milliseconds until the shutter starts to travel, causing a release time lag t lag ′ until the current of the control magnet for the shutter front curtain is turned off. . (See FIG. 8).

  The present invention has been made in view of the above points, and an object thereof is to provide an imaging device having a shutter device that suppresses a release time lag while being a simple shutter device.

In order to achieve the above object, in an imaging apparatus having a focal plane shutter according to the present invention, an exposure opening included in the focal plane shutter, and traveling through the opening to open the opening from a state in which the opening is closed. A leading curtain that moves to close the opening from a state retracted from the opening, a leading curtain armature that moves with the leading curtain, a trailing curtain armature that moves with the trailing curtain, and the leading curtain armature A first curtain electromagnet that electromagnetically attracts the first curtain armature to hold the first curtain armature at the start position of the first curtain, and a second curtain armature that electromagnetically attracts the second curtain armature at the start position of the second curtain. A rear curtain electromagnet that is attracted to the front curtain, a front curtain spring for applying an urging force to the front curtain for the travel, and a running force to the rear curtain. A rear-curtain spring for applying an urging force to the front curtain, a rotational drive source for storing the front-curtain spring and the rear-curtain spring, and the front-curtain spring for running the front-curtain A front-curtain accumulating member that is engaged with the front-curtain spring for accumulating the urging force for the purpose, and the rear-curtain spring for accumulating the urging force for causing the rear-curtain spring to run the rear curtain. And a pressing member for accumulating the urging force in each of the front curtain spring and the rear curtain spring, which are driven by the rotational drive source and are used for the two accumulators. A pressing member that moves between a pressing state position that presses the member and a non-pressing state position that does not press the two energy storage members, and a release signal output means for outputting a signal for starting the imaging And the shooting preparation before output from the release signal output means. In the state, advance by driving the rotation driving source is retracted into the movement locus outside of the pressing member the curtain prestressing member and the curtain prestressing member is moved to the non-pressing state position from the pressing state position In addition, current is supplied to the front curtain electromagnet and the rear curtain electromagnet, and the front curtain armature and the rear curtain armature are attracted to the front curtain electromagnet and the rear curtain electromagnet so that the front curtain and the rear curtain are While maintaining the travel start preparation position, the output from the release signal output means is received and the current supply to the front curtain electromagnet is cut off, and the current supply to the rear curtain electromagnet is cut off after a predetermined timing. And a control means.

  ADVANTAGE OF THE INVENTION According to this invention, although it is a simple shutter apparatus, the imaging device which has the shutter apparatus which suppressed release time lag can be provided.

It is a figure which shows a shutter charge state in the shutter mechanism of the shutter apparatus of this invention. It is a figure which shows a photography preparation state in the shutter mechanism of the shutter apparatus of this invention. It is a figure which shows the front curtain travel completion state in the shutter mechanism of the shutter apparatus of this invention. It is a figure which shows the completion | finish state of front curtain and rear curtain driving | running | working in the shutter mechanism of the shutter apparatus of this invention. It is a figure which shows the schematic electric circuit block diagram in the imaging device which has a shutter apparatus of this invention. It is a figure which shows the general flowchart of imaging | photography in the imaging device which has a shutter apparatus of this invention. It is a time chart explaining the operation | movement sequence explaining an invention part in the imaging device which has a shutter apparatus of this invention. It is a time chart explaining the operation | movement sequence in the imaging device which has the conventional shutter device.

  Hereinafter, the present invention will be described with reference to embodiments illustrated in principle.

  The mechanism itself, which is an embodiment of the present invention, is basically a publicly known and publicly used technique, and control using this mechanism has the main part of the invention.

  The embodiment of the present invention shows a shutter device applied to a camera or the like (hereinafter simply referred to as a camera) that is an imaging device that performs photography or the like.

  In each drawing used for the following description, each component may be shown with a different scale in order to make each component large enough to be recognized on the drawing. Therefore, according to the present invention, the number of constituent elements, the shape of the constituent elements, the ratio of the constituent element sizes, and the relative positional relationship of the constituent elements described in these drawings are limited to the illustrated embodiments. It is not a thing.

  1 to 4 are diagrams for explaining the operation of the shutter mechanism of the shutter device, and FIG. 1 is a diagram showing a shutter charge completion state. FIG. 2 is a transition diagram from FIG. 1 and is a diagram for explaining a photographing preparation state in which the charge member is retracted from the charged member after shutter charging. FIG. 3 is a transition diagram from FIG. 2 and is a diagram for explaining the middle of exposure when the leading curtain has completed traveling. FIG. 4 is a transition diagram from FIG. 3 for explaining the exposure completion state.

  FIG. 5 is an electric circuit block diagram for controlling the shutter mechanism shown in FIGS. 1 to 4 of the embodiment.

  FIG. 6 is a general flowchart showing the control operation of the shutter device of the present invention.

  FIG. 7 is a time chart showing the sequence operation of the shutter device of the present invention.

  FIG. 8 is a time chart for explaining an operation sequence in the conventional shutter device.

  1 to 4, the shutter mechanism 1 is shown. A base plate 1a (not shown) that supports the shutter device is provided with an opening 2 for exposing and blocking light from the imaging medium (imaging element 26). 1 and 2, the opening 2 is covered with a front curtain 3. Similarly, in FIGS. 1 to 3, the rear curtain 4 is retracted from the position where the opening 2 is present.

  In this description, the front curtain and the rear curtain are each briefly described with a single curtain, but in actuality, the curtain is composed of a group of publicly known and publicly used small curtains.

  The schematic configuration of the shutter mechanism 1 will be described below.

  At one of the four corners of the front curtain 3, one end of the first curtain first drive arm 3a is pivotally supported by a shaft 3c (oscillating shaft) so as to be relatively rotatable. Similarly, one end of the front curtain second drive arm 3e is pivotally supported on the other one of the four corners of the front curtain 3 by a shaft 3g (oscillating shaft). Further, the other end of the first curtain first drive arm 3a is pivotally supported by a base plate 1a (not shown) so as to be relatively rotatable by a shaft 3b. Similarly, the other end of the front curtain second drive arm 3e is pivotally supported on the main plate 1a so as to be relatively rotatable by a shaft 3f (swing shaft). Accordingly, a parallel link mechanism is constituted by a pair of arm members and curtain members, and the leading curtain 3 itself can move in parallel with the paper surface of the figure without rotating, and opens and closes the opening 2.

  The front curtain first drive arm 3a is provided with a front curtain armature 3d that can be attracted to the electromagnet. In a state where the front curtain 3 closes the opening 2, the armature 3d of the first curtain first drive arm 3a abuts against a contact adsorption surface of a yoke 5a serving as an electromagnet 5 provided on the base plate 1a. Further, a coil is wound around the yoke 5a, and if a current flows through the yoke 5a, the leading curtain armature 3d is adsorbed on the abutting adsorption surface of the yoke 5a. Further, the front curtain first drive arm 3a is hooked with a front curtain travel spring 7, which is a torsion spring provided around a shaft 3b (oscillating shaft), so that the front curtain first drive arm 3a is always rotated in the clockwise direction. Is energized.

  The first-curtain first drive arm 3a functions as a front-curtain accumulating member that charges (accumulates) the front-curtain running spring 7 in order to travel so that the front curtain 3 opens an opening, as will be described later.

  At one of the four corners of the rear curtain 4, one end of the rear curtain first drive arm 4a is pivotally supported by a shaft 4c (oscillating shaft) so as to be relatively rotatable. Similarly, at one of the four corners of the rear curtain 4, one end of the second curtain second drive arm 4e is pivotally supported by a shaft 4g (oscillating shaft). Furthermore, the other end of the rear curtain first drive arm 4a is pivotally supported on the main plate 1a so as to be relatively rotatable by a shaft 4b. Similarly, the other end of the second curtain second drive arm 4e is pivotally supported on the main plate 1a so as to be relatively rotatable by a shaft 4f (swinging shaft). Accordingly, a parallel link mechanism is constituted by the pair of arm members and the curtain member, and the rear curtain 4 itself can move in parallel with the paper surface in the drawing without rotating, and opens and closes the opening 2.

  The rear curtain first drive arm 4a is provided with a rear curtain armature 4d that can be attracted to the electromagnet. In a state where the rear curtain 4 closes the opening 2, the armature 4d of the rear curtain first drive arm 4a contacts the contact adsorption surface of the yoke 6a as the electromagnet 6 provided on the ground plate. Further, a coil is wound around the yoke 6a, and if a current flows through the yoke 6a, the armature 3d is adsorbed on the abutting adsorption surface of the yoke 6a. Further, the rear curtain first drive arm 4a is hooked with a rear curtain travel spring 8 which is a torsion spring provided around a shaft 4b (swinging shaft), so that the rear curtain first drive arm 4a is always rotated in the clockwise direction. Is energized.

  The rear curtain first drive arm 4a functions as a rear curtain accumulating member that charges (accumulates) the rear curtain traveling spring 8 in order to travel so that the rear curtain 4 closes the opening as will be described later.

  The shutter mechanism 1 further includes charging means for setting the front curtain and the rear curtain to a travel preparation state, that is, a shutter charge completion state. The charging means has a pressing member 9 as a charging member in order to charge (accumulate and bias) the front curtain travel spring 7 and the rear curtain travel spring 8. In the present embodiment, the pressing member 9 includes a front-curtain driven piece 3h that is a charged portion provided in the vicinity of the shaft 3f at the other end of the front-curtain second drive arm 3e, and a rear-curtain second drive arm 4e. The shutter is charged by pressing the trailing curtain driven piece 4h, which is a charged portion provided near the shaft 4f at the other end.

  The pressing member 9 presses the front curtain driven piece 3h and the rear curtain driven piece 4h to charge the front curtain travel spring 7 and the rear curtain travel spring 8 so as to charge. A pressing portion 9a for projecting and a pressing portion 9b for charging a rear curtain are provided. The pressing member 9 has a straight-advancing shape for guiding the first-curtain charge pressing portion 9a to contact the first-curtain driven piece 3h and the second-curtain charge pressing portion 9b to contact the second-curtain driven piece 4h. Guide grooves 9c are provided. In the guide groove 9c, a guide pin 10 provided on the base plate 1a is fitted, and the guide groove and the guide pin slide so that the pressing member can move relative to the base plate.

  The pressing member 9 is provided with a cam contact spring 11 that urges the pressing member 9 toward a cam member 12 described later. The pressing member 9 is provided with a pressed surface 9 d, and the cam surface 12 a of the cam member 12 is in contact with the urging action of the cam contact spring 11.

  The cam member 12 rotates about a rotating shaft 12b (cam rotating shaft) provided on the base plate, and a cam surface 12a is formed to increase and decrease the radial distance with the rotation.

  The electric circuit 20 is a diagram showing a schematic electric circuit block diagram in an imaging apparatus having the shutter device of the present invention as shown in FIG. 5, and controls the shutter mechanism 1.

  An ASIC 21 in the electric circuit 20 is an IC for controlling the shutter mechanism 1 and includes a memory in which a program as a control means for performing shutter control is written, a CPU, and various interfaces. The ASIC 21 is electrically connected to an imaging unit 26 a that receives an imaging signal from the imaging device 26 and performs necessary processing.

  The release switch 23 is connected to the ASIC 21 and functions as a release signal output unit. In particular, the release switch 23 is for outputting a signal for running the shutter to the ASIC 21. Normally, single-lens reflex cameras, compact cameras, etc. normally use a two-stage push switch for the release button. When the first switch is turned on, auto focus and AE calculation are performed, and then the shutter is turned on when the second switch is turned on. Let it run. In the present embodiment, the function of the first stage switch and the second stage switch is assumed to be one switch.

  A coil driver 5bb connected to the power switch 22 and the front curtain electromagnet coil 5b and a coil driver 6bb connected to the rear curtain electromagnet coil 6b are electrically connected to the ASIC 21, and the cam member 12 is further connected to the ASIC 21. A motor driver 24a connected to a charge motor 24 as a rotational drive source for rotationally driving the motor is electrically connected.

  Further, a cam position encoder 25 (not shown in FIGS. 1 to 4) for detecting the rotational position of the cam member 12, that is, detecting the charge state of the shutter, is electrically connected to the ASIC 21.

  As described above, the operation of the shutter device of the present invention constituted by the shutter mechanism 1 and the electric circuit 20 will be described with reference to the general flowchart shown in FIG. 6 and the time chart shown in FIG.

  When the power of the camera, which is an imaging device equipped with the shutter device, is turned on, the electric circuit mounted on the camera is initialized as shown in step S01 in FIG.

  Next, in step S02, the camera monitors whether or not the shootable mode is selected. If the shootable mode is selected, the process proceeds to the next step S03. If the photographable mode is not selected, the flow proceeds to a flow (not shown). This flow (not shown) is, for example, a reproduction mode for reproducing a recorded image, and the process proceeds there. In this description, since it is not related to the invention, its description is omitted. The shootable modes are various shooting modes, such as a known program mode, macro mode, night view mode, portrait mode, and the like.

  At the time of step S02, the shutter mechanism is in the state shown in FIG. 1, and the front curtain travel spring 7 and the rear curtain travel spring 8 for shutter travel are charged (accumulated). Thereafter, the leading curtain electromagnet 5 and the trailing curtain electromagnet 6 are turned ON (T0 in FIG. 7) in steps S03 and S04. That is, the yoke 5a sucks the armature 3d provided in the first curtain first drive arm 3a, and the yoke 6a sucks the armature 4d provided in the rear curtain first drive arm 4a.

  From this state, it is confirmed in step S05 whether or not the shutter charge is completed. If the shutter charge is complete, the process proceeds to step S06, and if the shutter charge is not complete, the process proceeds to step S16. In the camera in this description, when the power supply by the power switch 22 is turned off, the shutter is set to be held in a charged state (completed state). Therefore, usually, step S06 is entered immediately after step S05.

  At this time, as shown in FIG. 1, the pressing member 9 which is a charging member is positioned below by the cam member 12, and the leading curtain charging pressing portion 9a is in contact with the leading curtain driven piece 3h and is in a pressing state. The trailing-curtain charge pressing portion 9b is in contact with the trailing-curtain driven piece 4h and is in a charging complete state, which is a pressing state. In this state, the front curtain driven piece 3h and the rear curtain driven piece 4h are both in the way and cannot travel. Therefore, the front-curtain charge pressing portion 9a of the pressing member 9 is retracted out of the movement locus of the front-curtain driven piece 3h, and the rear-curtain charge pressing portion 9b of the pressing member 9 is moved to the rear-curtain driven piece 4h. Must be evacuated outside the trajectory. Therefore, if it is determined in step S06 that the pressing member 9 is in contact with the front-curtain driven piece 3h and the rear-curtain driven piece 4h, which are pressed parts (charged parts), the process proceeds to step S07.

  In step S06, the pressing member 9 is not in contact with the front-curtain driven piece 3h and the rear-curtain driven piece 4h, which are pressed portions (charged portions), that is, the pressing member 9 is not pressed (charged). If it is determined that the user is evacuating outside the movement locus of (part), the process proceeds to step S08.

  In step S07, the front-curtain charge pressing portion 9a and the rear-curtain charge pressing portion 9b of the pressing member 9 are determined from the rotational movement trajectories of the front-curtain driven piece 3h and the rear-curtain driven piece 4h that are charged portions. In order to evacuate, the charging motor 24 is supplied with electric power from the motor driver 24a, rotates the cam member 12 in the clockwise direction indicated by the arrow A in FIG. 1, and receives the urging force of the cam contact spring 11. 9 is moved above the arrow B in FIG. 1 by the action of the cam surface 12a. If the cam position encoder 25 determines that the pressing member 9 has retreated from the rotational movement trajectory of the front curtain driven piece 3h and the rear curtain driven piece 4h, the process proceeds to step S08. At this point, the shutter mechanism shifts to the state shown in FIG.

  In step S08, it is monitored whether a release signal is output. This means whether or not the release button of the camera has been depressed. If the release signal is not output, the process proceeds to step S17 described later. Until the release signal is output, the loop consisting of steps S08 to S17, S03, S04, S05, S06, and S08 is repeated.

  If the release button is pressed down and a release signal is output, the process proceeds to step S09, and AE calculation (automatic exposure calculation) is performed based on the output from the image sensor 26.

  Next, in step S10, the current flowing through the coil 5b of the front curtain electromagnet 5 is interrupted, and the magnet function is stopped. Since the front curtain armature 3d is provided on the first curtain first drive arm 3a on which the front curtain travel spring 7 charged counterclockwise is hooked, the front curtain armature 3d attracted to the electromagnet yoke 5a is provided. Is separated from the yoke 5a. Since the front curtain second drive arm 3e and the front curtain first drive arm 3a rotate and rotate in the clockwise direction, the front curtain 3 retreats from the opening 2 and opens the opening as shown in FIG.

  In step S12, the shutter time is measured in step S12, which is a predetermined time tv obtained from the result of the AE calculation, starting from the current interruption to the coil 5b. In step S12, it is determined that the time has elapsed in the predetermined time tv. Repeat the process.

  If it is determined that the time has elapsed for a predetermined time tv, the process proceeds to step S13, the current flowing through the coil 6b of the trailing curtain magnet 6 is cut off, and the magnet function is stopped. As a result, the trailing curtain armature 4d adsorbed to the electromagnet yoke 6a is separated from the yoke 6a because the trailing curtain running spring 8 charged counterclockwise is hooked on the trailing curtain first drive arm 4a. . Along with this, the rear curtain first drive arm 4a swings and rotates in the clockwise direction, and the rear curtain second drive arm 4e also swings and rotates in the clockwise direction together with the rear curtain first drive arm 4a. The running is started and the opening 2 is closed as shown in FIG.

  Tv in FIG. 7 indicates the predetermined time. This predetermined time may be set so that the trailing curtain 4 starts traveling while the leading curtain 3 is traveling, and this is determined by the result of the AE calculation.

  Since a certain time is necessarily required from the start of the trailing curtain to the completion of the trailing curtain from the start of traveling, this time is counted in step S14. After this timing is completed, the image data captured by the image sensor 26 is recorded in a storage device inside the camera in step S15.

  When this recording is completed, in step S16, the charge motor 25 is driven, the cam member 12 is rotated in the clockwise direction of the arrow C shown in FIG. 4, and the pressing member 9 is used for cam contact below the arrow D shown in FIG. The pressure is displaced against the urging force of the spring 11. Therefore, the pressing portion 9a presses the front curtain driven piece 3h, and the pressing portion 9b presses the rear curtain driven piece 4h to charge the springs 7 and 8 to charge the shutter mechanism 1 to prepare for the next shutter release. That is, the process proceeds to the state of FIG. 1 and proceeds to the next step S17.

  In step S17, it is monitored whether the camera is turned off. If the camera is still turned on, the process returns to step S02. Normally, when a release is performed, the shutter charging starts and ends immediately after the shutter operation and immediately after the operation of the photographer. Therefore, when returning to step S02, steps S02 to S06, S06 to S07, and S08 are directly performed. To S17. Therefore, the position of the pressing member 9 is in the position shown in FIG. 2 and is not in contact with the front curtain driven piece portion 3h and the rear curtain driven piece portion 4h. That is, the pressing member 9 moves the pressed portion (charged portion). It is in a position where it is retracted out of the locus.

  If the camera power supply is OFF in step S17, the charge motor 24 is driven via the motor driver 24a in step S18, the cam member 12 is rotated in the clockwise direction of the arrow E in FIG. 2 is positioned downward in the direction of the arrow F in FIG. 2 against the urging force of the cam contact spring 11, and the leading curtain charge pressing portion 9a is placed on the leading curtain driven piece 3h to drive the trailing curtain. The rear curtain charge pressing portion 9b is brought into contact with the one portion 4h, and the setting is maintained at the charge completion position. That is, the same state as in FIG. 1 is obtained. Thereafter, the CPU of the ASIC 21 is set in the HALT state or the sleep state.

  Since the cam member 12 and the charge motor 24 are connected by a reduction gear train (not shown), the cam member 12 does not rotate freely by the biasing force of the cam contact spring 11 unless the charge motor 24 rotates. The pressing member 9 also does not move arbitrarily.

  In recent years, cameras capable of live view have been provided. That is, a camera is provided that always displays a moving image of a subject on the display screen on the back of the camera, waits for a camera release instead of a viewfinder, and operates a shutter when a release operation is performed to take a still image. In this case, there is provided a mechanism for retracting the front curtain, which should originally close the photographing opening of the shutter base plate, from the photographing opening while maintaining the shutter front curtain and rear curtain in the charged state. . However, even if the camera has this mechanism, the front curtain covers the opening again during shooting and the shutter starts to travel. Therefore, if the shutter time lag is to be eliminated, the present invention is required.

As described above, according to the imaging device having the shutter device of the present invention, the selection from the camera power-on to the shootable mode is completed, and the shutter charging member is immediately retracted from the charged member of the shutter. Therefore, the shutter time lag is extremely small.
Similarly, even after the first shutter release, the shutter time lag is extremely small.

  The camera generally has a function of automatically turning off the power when the camera is in a shooting preparation state, that is, when the release operation is not performed for a long time with the power on. In this case, a monitor function step for measuring the long time is added between step S17 and step S02 in the flowchart of the camera, and if the long time has not elapsed, the process proceeds to step S02, and each long time has elapsed. If it is determined that the image has been determined, the process may proceed to step S18, and the camera can be used in exactly the same manner after the next imaging power is turned on.

  In the description of the present invention, the pressing member 9 has been described as a member that linearly moves. However, the pressing member 9 may be configured by a rotating member that interlocks with the rotation of the cam member.

  Note that the present invention is not limited to the above-described embodiment, and various modifications and applications can of course be implemented without departing from the spirit of the invention. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the above-described embodiment, if the problem to be solved by the invention can be solved and the effect of the invention can be obtained, this constituent requirement is deleted. The configured structure can be extracted as an invention.

  The present invention can be similarly applied to an electronic device having a function of acquiring an image using an imaging element, for example, a device having a shutter device such as a camera using a silver salt film or a digital camera.

DESCRIPTION OF SYMBOLS 1 ... Shutter mechanism 2 ... Base plate opening 3 ... Front curtain (front blade)
3a: Front curtain first drive arm 3b: Oscillating shaft 3c ... Oscillating shaft 3d ... Front curtain armature 3e ... Front curtain second driving arm 3f ... Oscillating shaft 3g ..Oscillating shaft 3h ... front curtain driven piece 4 ... rear curtain (rear blade)
4a ... Rear curtain first drive arm 4b ... Oscillating shaft 4c ... Oscillating shaft 4d ... Rear curtain armature 4e ... Rear curtain second driving arm 4f ... Oscillating shaft 4g ..Oscillating shaft 4h ... rear curtain driven piece 5 ... front curtain electromagnet 5a ... yoke 5b ... coil (front curtain electromagnet coil)
5bb ... Coil driver 6 ... Rear curtain electromagnet 6a ... Yoke 6b ... Coil (rear curtain electromagnet coil)
6bb ... Coil driver 7 ... Spring for front curtain travel (front curtain spring)
8 ... Rear curtain spring (rear curtain spring)
9 ... Pressing member (charging member)
9a... First curtain charge pressing portion 9b... Rear curtain charging pressure portion 9c... Guide groove 10... Guide pin 11.・ Cam surface 12b ・ ・ ・ Cam rotation shaft 20 ・ ・ ・ Electric circuit 21 ・ ・ ・ ASIC
DESCRIPTION OF SYMBOLS 22 ... Power switch 23 ... Release switch 24 ... Charge motor 24a ... Motor driver 25 ... Cam position encoder 26 ... Imaging element 26a ... Imaging part

Claims (1)

In an imaging apparatus having a focal plane shutter,
An opening for exposure of the focal plane shutter;
A front curtain that travels through the opening to open the opening from a state in which the opening is closed;
A rear curtain that travels to close the opening from the state of being retracted from the opening;
The front curtain armature that moves with the front curtain,
The trailing curtain armature that moves with the trailing curtain,
In order to hold the front curtain armature at the travel start position of the front curtain, a front curtain electromagnet that electromagnetically attracts the front curtain armature;
A rear curtain electromagnet that electromagnetically attracts the rear curtain armature to hold the rear curtain armature at the running start position of the rear curtain;
A front curtain spring for giving the front curtain a biasing force for causing the front curtain to travel,
A rear curtain spring for applying an urging force to the front curtain to the front curtain;
A rotational drive source for storing the front curtain spring and the rear curtain spring;
A front curtain accumulating member on which the front curtain spring is hung to accumulate the urging force for causing the front curtain spring to travel the front curtain;
A rear curtain accumulating member on which the rear curtain spring is hung to accumulate the urging force for causing the rear curtain spring to travel the rear curtain;
A pressing member for accumulating the urging force in each of the front curtain spring and the rear curtain spring, wherein the pressing state position is driven by the rotational drive source and presses the two accumulating members; A pressing member that moves to a non-pressing position that does not press the two energy storage members;
A release signal output means for outputting a signal for starting the photographing;
In a shooting preparation state before output from the release signal output means, the rotary drive source is driven to move the pressing member from the pressing state position to the non-pressing state position, thereby causing the front curtain accumulating member and the rear curtain to move. Retract from the movement path of the energy storage member, supply current to the front curtain electromagnet and the rear curtain electromagnet, and attract the front curtain armature and the rear curtain armature to the front curtain electromagnet and the rear curtain electromagnet. With the front curtain and the rear curtain maintained at the travel start preparation position, the output from the release signal output means is received and the current supply to the front curtain electromagnet is cut off. Control means for controlling the current supply to the curtain electromagnet to cut off,
An imaging apparatus having a focal plane shutter characterized by comprising:

Images