JP2011141400A - Shutter opening/closing mechanism, and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mechanism that drives to open/close a shutter with simple configuration. <P>SOLUTION: The shutter opening/closing mechanism includes: the shutters 12 and 13; a base plate 14 which supports the shutters 12 and 13 turnably, and where an opening 26 on which external light is incident is formed; and a ring member 15 which is supported on the base plate 14 rotatably, and engaged with the shutters 12 and 13 to turn the shutters 12 and 13 in an opening direction of the opening 26 by rotating them in one direction, and turn the shutters 12 and 13 in a closing direction of the opening by rotating in the other. Either one of the base plate 14 and the ring member 15 is provided with a pair of magnets 34 and 35 in such a state that magnetic poles on an opposing side agree with each other, and the other is provided with a yoke 16 which is arranged between the pair of magnets and around the center part of which a coil 43 is wound. By reversing a direction of current of the coil 43, the magnetic poles at both ends of the yoke 16 are reversed, whereby the yoke 16 and the pair of magnets 34 and 35 are magnetically attracted or repulsed, to rotate the ring member 15. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a shutter opening / closing mechanism that covers the front of an imaging lens and an imaging element, protects the imaging lens, or controls exposure, and an imaging device in an imaging apparatus such as a digital still camera or a video camera.

  Conventionally, in an imaging apparatus such as a digital still camera or a video camera, a lens barrier mechanism that covers the front of the imaging lens and protects the imaging lens is mounted. The lens barrier mechanism is disposed on the front surface of the lens barrel, and generally includes a plurality of shutter blades and a driving unit that drives the shutter blades (see Patent Document 1).

  For example, a conventional lens barrier mechanism 100 shown in FIG. 12 includes a circular front cover 101 incorporated in the front surface portion of the lens barrel, a shutter blade 102 rotatably supported by the front cover 101, and a front cover 101. A base plate 103 that sandwiches the shutter blades 102, a rotating plate 104 that rotates the shutter blades 102 with respect to the front cover 101, and a gear mechanism disposed in a gear box 105 formed on the outer periphery of the front cover 101. 106.

  The front cover 101 has an opening at the center that allows the imaging lens to face the front. The shutter blades 102 are composed of four sheets, and are rotatably supported by the front cover 101 and are rotatably supported by the front cover 101 and two main shutters 102a that engage with the rotating plate 104. It has two driven shutters 102b that engage with the main shutter 102a and rotate following the main shutter 102a. The main shutter 102 a is rotatably supported by the front cover 101, and a driving pin (not shown) protruding from the rotating plate 104 is inserted and engaged, and is rotated according to the rotation of the rotating plate 104.

  The base plate 103 has the same size as the front cover 101, and similarly has an opening at the center. The base plate 103 is formed with a ring-shaped concave surface portion 107 into which the rotating plate 104 is fitted.

  The rotating plate 104 has a substantially circular shape and is rotatably fitted in the concave surface portion 107 of the base plate 103. Further, the rotation plate 104 is provided with a drive pin for rotating the main shutter 102a so as to be engaged with the main shutter 102a. Further, the rotating plate 104 is formed with a gear portion 108 that meshes with the gear mechanism 106, and is rotated by the gear mechanism 106 in the direction of arrow R and the direction of the counter arrow R in FIG. Further, the rotation plate 104 has a fin 111 protruding from the upper surface of the gear portion 108 that is detected by the motor control sensor 110.

  The gear mechanism 106 includes a driving motor 112, a plurality of connecting gears 113 that connect the driving motor 112 and the gear portion 108 of the rotating plate 104, and a motor that controls the driving of the driving motor 112 according to the rotational position of the rotating plate 104. And a control sensor 110.

  In such a lens barrier mechanism 100, when the drive motor 112 is driven, the rotating plate 104 is rotated in the arrow R direction and the counter arrow R direction in FIG. Thereby, the main shutter 102a and the driven shutter 102b are rotated, and the imaging lens is opened and closed. In the lens barrier mechanism 100, the drive of the drive motor 112 is controlled by the fin 111 of the rotating plate 104 moving the motor control sensor 110 forward and backward, and the shutter blade 102 is rotated to the open position or the closed position.

JP 2008-158248 A

  By the way, since the lens barrier mechanism 100 rotates the shutter blade 102 by the gear mechanism 106, the image pickup lens is not inadvertently opened or closed by the swing of the shutter blade 102, and the user does not have the shutter. Even when the blade 102 is to be rotated, the rotation of the shutter blade 102 can be restricted.

  On the other hand, since the lens barrier mechanism 100 uses the gear mechanism 106 to rotate the shutter blade 102, a gear mechanism 106 and a gear box 105 that houses the gear mechanism 106 are necessary. For this reason, the image pickup apparatus provided with such a lens barrier mechanism 100 causes an increase in the number of parts and an increase in manufacturing man-hours by the parts constituting the gear mechanism 106 and the gear box 105. In addition, as shown in FIGS. 13A and 13B, the imaging device 120 including the lens barrier mechanism 100 is formed such that the gear box 105 projects from the peripheral surface of the lens barrel 121a on the front surface 121a of the lens barrel 121. As a result, the lens barrel 121 is increased in size.

  Furthermore, since the front surface portion 121a of the lens barrel 121 is divided as a space for disposing the gear box 105, the imaging device 120 cannot secure a space for disposing other components such as a strobe. The degree of freedom is lost.

  Also, in order to prevent inadvertent opening or closing of the shutter blades, the shutter blades are always urged in the closing direction using a spring, and the shutter blades are countered against the urging force of the spring by driving the motor and gear. There is also a mechanism for rotating in the opening direction. However, in this method, when the shutter blade is rotated in the direction opposite to the spring biasing direction, a torque greater than the spring biasing force is required, and the torque increases as it rotates in the opening direction. It is necessary to maintain the open state with torque.

  There is also a mechanism for rotating the shutter blades until the biasing direction is reversed by a motor and a gear by rotating the shutter blades in an opening direction or a closing direction by a spring or magnet whose rotation direction is reversed during rotation. However, in this method, the impact resistance is weak, and the shutter blades are swung carelessly. Further, when the impact resistance is increased, a larger torque is required for the motor that rotates the shutter blades against the urging force of the spring or magnet. This method also requires a motor and a gear mechanism.

  In addition, there is a method of controlling the amount of rotation of the motor to restrict the swinging of the shutter blades with the driving force of the motor even when the shutter blades are closed, but when an external impact is applied in addition to the motor torque, A large load is applied to the shutter blades, and the shutter blades may be damaged.

  Furthermore, the method of adding a stopper mechanism that restricts the swinging of the shutter blades causes an increase in the number of parts and an increase in the size of the lens barrel, and there is a concern that the number of manufacturing steps and the yield may be deteriorated.

  Accordingly, an object of the present application is to provide a shutter opening / closing mechanism capable of smoothly opening and closing a shutter with a simple configuration, and an imaging apparatus including the shutter opening / closing mechanism.

  In order to solve the above-described problems, a shutter opening / closing mechanism according to the present invention includes a shutter, a base plate in which the shutter is rotatably supported, and an opening through which external light is incident is formed, and the base plate The shutter is engaged with the shutter, rotated in one direction to rotate the shutter in the opening direction of the opening, and rotated in the other direction to close the shutter in the opening. A ring member that rotates in a direction, and the base plate and the ring member are provided such that either one of the pair of magnets is aligned with the opposite magnetic pole, and the other is the pair of magnets. And a yoke around which a coil is wound is provided at the center, and by reversing the direction of the current of the coil, the magnetic poles at both ends of the yoke are reversed. By click and the the pair of magnets magnetically attracting or repelling, those for rotating the ring member.

  An image pickup apparatus according to the present invention includes: a lens barrel including an image pickup element and an image pickup lens; and an image pickup apparatus including a shutter opening / closing mechanism that controls incidence of a light beam into the lens barrel. The shutter opening / closing mechanism supports the shutter, the shutter so as to be rotatable, a base plate formed with an opening through which external light is incident, a base plate rotatably supported by the base plate, and the shutter. A ring member that rotates the shutter in the opening direction of the opening by rotating in one direction and rotates the shutter in the closing direction of the opening by rotating in the other direction, The base plate and the ring member are provided with either one of the magnetic poles on the side where the pair of magnets are opposed to each other, and are disposed between the pair of magnets on the other and the center. A yoke around which a coil is wound is provided, the magnetic poles at both ends of the yoke are reversed by reversing the current direction of the coil, and the yoke and the pair of magnets are magnetically attracted or repelled. The ring member is rotated.

  According to the present invention, the shutter can be rotated with a simple configuration. In particular, according to the present invention, since it is not necessary to provide a drive motor or a connecting gear mechanism in the vicinity of the shutter, it is possible to reduce the number of parts and eliminate the need for a gear box by applying it to an imaging device such as a video camera. Thus, the lens barrel can be reduced in size, and the degree of freedom in design can be secured.

It is a perspective view showing a video camera to which the present invention is applied. It is a side view which shows the video camera to which this invention was applied. It is a disassembled perspective view which shows a shutter opening / closing mechanism. It is a top view which shows the shutter opening / closing mechanism which hold | maintains a shutter in an open position, (a) shows the surface side of a base board, (b) shows the back surface side of a base board. It is a top view which shows the shutter opening and closing mechanism which hold | maintains a shutter in the obstruction | occlusion position, (a) shows the surface side of a base board, (b) shows the back surface side of a base board. It is a perspective view which shows another shutter opening / closing mechanism. It is a side view which shows another shutter opening / closing mechanism. It is a perspective view which shows another shutter opening / closing mechanism. It is a side view which shows another shutter opening / closing mechanism. It is a side view which shows another shutter opening / closing mechanism. It is a side view which shows another shutter opening / closing mechanism. It is a perspective view which shows the conventional lens barrier mechanism. It is a figure which shows the conventional imaging device, (a) is a perspective view, (b) is a side view.

Hereinafter, a shutter opening / closing mechanism to which the present invention is applied and an image pickup apparatus including the shutter opening / closing mechanism will be described in detail with reference to the drawings. The description will be given in the following order.
1. 1. Imaging device Shutter opening / closing mechanism

<1. Imaging device>
An imaging apparatus to which the present invention is applied is, for example, a handy type video camera 1 that can be held and operated with one hand as shown in FIGS. And a display panel 3 connected to each other. The video camera 1 uses, for example, a memory or a hard disk built in the apparatus main body 2 as a main recording medium, and converts an optical image captured via an imaging lens into an electrical signal using an imaging element such as a CCD or CMOS. After the conversion, it is recorded on a memory or a hard disk, and can be displayed on the display panel 3. In addition, the video camera 1 converts audio captured via a built-in microphone into an audio signal by an AD / DA converter, records it on a memory or a hard disk, and outputs it from a built-in speaker.

  The apparatus body 2 is formed by projecting a lens barrel 5 having an imaging lens group disposed on the front surface. The lens barrel 5 has a shutter that is provided on the front surface and functions as a lens barrier that protects the imaging lens 6 that faces outward during photographing, and a shutter opening / closing mechanism 10 that opens and closes the shutter. . The shutter opening / closing mechanism 10 will be described in detail later.

  In addition, the apparatus main body 2 has a grip portion 7 that is gripped by the user on the right side surface. The grip 7 is provided with a start / stop button used for moving image shooting, a release button used for still image shooting, a zoom lever, and the like. Further, the apparatus body 2 is formed with a pop-up strobe device 8 on the upper surface of the lens barrel 5.

  A display panel 3 is supported on the left side surface of the apparatus body 2. The display panel 3 is connected to the front side of the left side surface of the apparatus body 2 via a hinge mechanism 9. The hinge mechanism 9 has a first rotation shaft provided across the vertical direction of the apparatus main body 2 and a second rotation axis provided across the horizontal direction of the apparatus main body 2, and the display panel 3 is It is supported so as to be rotatable in directions orthogonal to each other.

  For example, a liquid crystal display panel on which a touch panel is superimposed is used as the display panel 3, which serves as a display unit that displays an image and also functions as an operation panel. Specifically, the display panel 3 includes a panel casing that forms a part of the outer casing of the apparatus main body 2 by being rotated to the left side of the apparatus main body 2, and the liquid crystal module and the liquid crystal are included in the panel casing. An input display module in which a touch panel superimposed on the module is integrated is provided.

  In addition to the liquid crystal panel, an organic EL (Electroluminescence) panel or other flat monitor can be used as the input display module. In addition, the input display module can use a resistive touch panel having two film substrates each provided with a transparent electrode on opposite surfaces as a touch panel. Various touch panels such as an ultrasonic type can also be used.

<2. Shutter open / close mechanism>
Next, the shutter opening / closing mechanism 10 provided in the lens barrel 5 will be described. The shutter opening / closing mechanism 10 opens and closes a shutter that functions as a lens barrier that protects the imaging lens 6 disposed on the front side of the lens barrel 5, and prevents the shutter from being opened and closed inadvertently. As shown in FIGS. 3 to 5, the shutter opening / closing mechanism 10 rotates the front cover 11, the inner shutter 12, the outer shutter 13, the inner shutter 12 and the outer shutter 13 in order from the front side of the lens barrel 5. A base plate 14 that is movably supported, a ring member 15 that rotates the inner shutter 12 and the outer shutter 13, and a yoke 16 that rotates the ring member 15 are provided.

  The shutter opening / closing mechanism 10 rotates the ring member 15 to one side or the other side by the yoke 16, thereby opening the inner shutter 12 and the outer shutter 13 to the openings 20 and 26 formed in the front cover 11 and the base plate 14. Is rotated to an open position for opening and a closed position for closing each of the openings 20 and 26, and held at each position.

  The front cover 11 sandwiches the inner shutter 12 and the outer shutter 13 together with the base plate 14 so as to be rotatable, and is made of a metal plate having substantially the same size as the base plate 14. The front cover 11 is formed with a cover opening 20 that allows the imaging lens 6 to face outward, and a plurality of insertion holes 22 that engage with convex portions (not shown) protruding from the base plate 14. The front cover 11 has a support hole 23 through which a support pin 27 supporting the shutters 12 and 13 projecting from the base plate 14 is inserted, and a rotation shaft 36 of the ring member 15. A shaft hole 24 opened in an arc shape is formed in accordance with the rotation trajectory.

  The front cover 11 is engaged with the base plate 14 by engaging convex portions (not shown) of the base plate 14 with the plurality of insertion holes 22. Further, the front cover 11 inserts the support pins 27 of the base plate 14 through which the shutters 12 and 13 are inserted into the support holes 23 so that the shutters 12 and 13 are rotatably held together with the base plate 14.

  The base plate 14 sandwiches the shutters 12 and 13 together with the front cover 11 on the front side of the lens barrel 5 and supports the ring member 15 and the yoke 16 on the back side of the lens barrel 5. The base plate 14 is formed of a plate-like body provided with a base opening 26 that allows the imaging lens 6 to face outward in the center. The inner shutter 12 and the outer shutter 13 are provided on the front surface 14 a of the lens barrel 5. Are formed with a plurality of convex portions (not shown) that engage with the front cover 11 and a shaft insertion hole 29 through which the rotation shaft 36 of the shutter rotation member 15 is inserted. Yes.

  A pair of support pins 27 is provided at the peripheral edge of the surface 14a, one support pin 27 coaxially supports one inner shutter 12 and the outer shutter 13, and the other support pin 27 is the other inner shutter 12 and the outer side. The shutter 13 is supported coaxially. When the support pins 27 are inserted into the support holes 23 of the front cover 11, the base plate 14 holds the inner shutter 12 and the outer shutter 13 together with the front cover 11 so as to be rotatable about the support pins 27.

  The shaft insertion hole 29 is a through hole that passes through the front and back surfaces 14 a and 14 b of the base plate 14 and through which the rotation shaft 36 of the ring member 15 supported by the back surface 14 b is inserted, and is provided in the vicinity of each support pin 27. It has been. The shaft insertion hole 29 is opened in an arc shape according to the turning locus of the turning shaft 36 of the ring member 15. After the rotation shaft 36 is inserted through the shaft insertion hole 29, the rotation shaft 36 is inserted through the engagement holes 41 of the inner shutter 12 and the outer shutter 13 and is inserted into the shaft hole 24 of the front cover 11.

  Further, the base plate 14 is provided with a rotation support piece 30 that protrudes from the periphery of the rear surface 14 b on the back side of the lens barrel 5 so as to rotatably support the ring member 15. A plurality of the rotation support pieces 30 are formed on the outer periphery of the support wall 31 erected on the periphery of the base opening 26 on the back surface 14 b, and prevent the ring member 15 from falling off from the back surface 14 b and on the outer periphery of the support wall 31. It is supported so that it can rotate along.

  Further, the base plate 14 is provided with an engaging support piece 32 for supporting the yoke 16 on the back surface 14b. The engagement support pieces 32 support both ends of the yoke 16, and a pair of engagement support pieces 32 are provided according to the length of the yoke 16.

  As shown in FIG. 3, the ring member 15 supported by the rotation support piece 30 includes a main body portion 33 rotatably supported by the base plate 14, and a pair of magnets 34 and 35 attached to the outer periphery of the main body portion 33. And a rotation shaft 36 that is inserted into an engagement hole 41 provided in the inner shutter 12 and the outer shutter 13.

  The main body 33 has a ring shape, and a locking projection 33a supported on the rotation support piece 30 protruding from the base plate 14 is formed on the inner peripheral surface. The main body 33 is prevented from falling off the base plate 14 by locking the locking projection 33 a between the back surface 14 b of the base plate 14 and the rotation support piece 30.

  Further, the main body portion 33 is provided with a mounting piece 33b to which the magnets 34 and 35 are attached on the outer peripheral surface. A pair of mounting pieces 33b are provided on the outer peripheral surface of the main body 33 with a predetermined clearance therebetween, and magnets 34 and 35 are mounted on the surface opposite to the surface facing the back surface 14b of the base plate 14. For example, as shown in FIGS. 4B and 5B, the N pole part 34N and the N pole part 35N face each other so that the magnets 34 and 35 have the same magnetic poles on opposite sides. And attached to each attachment piece 33b. The main body 33 rotates around the support wall 31 when these magnets 34 and 35 and a yoke 16 described later are attracted or repelled by magnetic force.

  Further, the main body portion 33 is provided with a pivot shaft 36 for projecting the inner shutter 12 and the outer shutter 13 on the end surface facing the back surface 14 b of the base plate 14. The rotation shaft 36 is inserted through the shaft insertion hole 29 of the base plate 14 and protrudes toward the surface 14a side, and is inserted through the engagement hole 41 formed on the proximal end side of the inner shutter 12 and the outer shutter 13. Further, it is inserted through the shaft hole 24 of the front cover 11. When the main body 33 is rotated by a yoke 16 described later, the rotation shaft 36 is rotated in an arc shape in the engagement hole 41 to rotate the inner shutter 12 and the outer shutter 13.

  Here, the inner shutter 12 and the outer shutter 13 rotated by the ring member 15 will be described. Two inner shutters 12 and two outer shutters 13 are provided. The two inner shutters 12 open and close the substantially central portions of the openings 20 and 26, and the two outer shutters 13 and the peripheral edges of the openings 20 and 26. Open and close parts.

  The inner shutter 12 and the outer shutter 13 are formed in a long plate shape, and a pin hole 40 through which the support pin 27 of the base plate 14 is inserted is formed on one end side. The inner shutter 12 and the outer shutter 13 are rotatably supported on the surface 14 a side of the base plate 14 by the support pins 27 and are prevented from falling off by the front cover 11.

  Further, the inner shutter 12 and the outer shutter 13 are formed with an engagement hole 41 on one end side through which the rotation shaft 36 of the ring member 15 is inserted and engaged. The inner shutter 12 and the outer shutter 13 are adapted to the rotation of the ring member 15 by the rotation shaft 36 protruding to the surface 14a side through the shaft insertion hole 29 of the base plate 14 being inserted into the engagement hole 41. Then, it is rotated between the open position where it is pressed by the rotation shaft 36 to open the openings 20 and 26 (FIG. 4A) and the closed position where it is closed (FIG. 5A). Further, the engagement hole 41 is formed in a long hole shape according to the turning locus of the turning shaft 36.

  Next, the yoke 16 that rotates the ring member 15 will be described. The yoke 16 is attached to an engagement support piece 32 protruding from the back surface 14 b of the base plate 14. The yoke 16 has a substantially cylindrical shape, and is fitted into a bobbin around which a coil 43 is wound at the center.

  When the ring member 15 is supported by the base plate 14, the yoke 16 has one end in the longitudinal direction facing the magnet 34 of the ring member 15 and the other end facing the magnet 35 of the ring member 15. . As described above, the magnets 34 and 35 of the ring member 15 are attached so that the magnetic poles on the opposite sides are the same. Therefore, in the yoke 16, both ends in the longitudinal direction and the magnets 34 and 35 attract each other and repel each other.

  The coil 43 wound around the center of the yoke 16 is connected to a circuit board (not shown), and the direction of current is switched according to the opening / closing direction of the shutters 12 and 13. Therefore, in the yoke 16, the magnetic poles at both ends in the longitudinal direction are inverted according to the direction in which the current flows.

  Next, the operation of the shutter opening / closing mechanism 10 will be described with reference to FIGS. As shown in FIG. 4, in the state where the inner shutter 12 and the outer shutter 13 are held at the open positions where the openings 20 and 26 are opened, the engagement holes 41 are formed by the rotation shaft 36 in the openings 20 and 26. It is pressed to the outside. At this time, the ring member 15 is magnetically attracted by the one end 16a of the yoke 16 and the magnet 34, and is urged to rotate in the direction of arrow O in FIG. Therefore, in the ring member 15, as shown in FIG. 4A, the rotation shaft 36 holds the inner shutter 12 and the outer shutter 13 in the open position.

  When a current is passed through the coil 43 in a predetermined direction from the state where the shutters 12 and 13 are held at the open position, the yoke 16 has one end 16a facing the magnet 34 at the N pole and the other end facing the magnet 35. 16b becomes the south pole. As a result, the ring member 15 rotates in the direction of arrow C in FIG. 5B when the magnet 34 repels the one end 16 a of the yoke 16 and the magnet 35 is attracted to the other end 16 b of the yoke 16. When the ring member 15 is rotated in the direction of arrow C, the inner shutter 12 and the outer shutter 13 are rotated in the direction of arrow A in FIG. .

  At this time, the pair of inner shutters 12 are abutted against each other to restrict the rotation in the direction of arrow A, and thereby the rotational positions of the rotation shaft 36 and the ring member 15 in the direction of arrow C are defined. Further, by defining the rotation position of the ring member 15 in the arrow C direction, the pair of outer shutters 13 is also defined in the rotation position in the arrow A direction. The inner shutter 12 closes the central portion of the openings 20 and 26, and the outer shutter 13 is rotated to a position partially overlapping with the inner shutter 12 and closes the outside of the openings 20 and 26. .

  Further, the ring member 15 is urged in the direction of the arrow C by magnetically attracting the other end 16b of the yoke 16 to the magnet 35 even after power supply to the coil 43 is interrupted. Therefore, the inner shutter 12 and the outer shutter 13 are prevented from swinging and are held at the closed position.

  When opening the openings 20 and 26, a current in a direction opposite to the predetermined direction is passed through the coil 43 to reverse the magnetic poles at both ends of the yoke 16. That is, as shown in FIG. 4B, the yoke 16 has one end 16 a facing the magnet 34 as an S pole and the other end 16 b facing the magnet 35 as an N pole. As a result, the ring member 15 rotates in the direction of arrow O in FIG. 4B when the magnet 34 is attracted to the one end 16 a of the yoke 16 and the magnet 35 repels the other end 16 b of the yoke 16. When the ring member 15 is rotated in the direction of arrow O, the inner shutter 12 and the outer shutter 13 are rotated in the direction of arrow B in FIG. 4A where the openings 20 and 26 are opened by the rotation shaft 36. .

  At this time, the pair of inner shutter 12 and outer shutter 13 is restricted from rotating in the direction of arrow B by abutting against a locking wall erected on the surface 14 a of the base plate 14, thereby rotating The rotational position of the shaft 36 and the ring member 15 in the direction of arrow O is defined. The inner shutter 12 and the outer shutter 13 are rotated to an open position that is outside the openings 20 and 26.

  Further, the ring member 15 is urged in the direction of the arrow O by magnetically attracting the one end 16a of the yoke 16 to the magnet 34 even after the supply of power to the coil 43 is interrupted. Therefore, the inner shutter 12 and the outer shutter 13 are prevented from swinging and are held in the open position.

  By using such a yoke 16, the shutter opening / closing mechanism 10 can rotate the inner shutter 12 and the outer shutter 13 with a simple configuration. In particular, the shutter opening / closing mechanism 10 does not need to be provided with a drive motor or a connecting gear mechanism in the vicinity of the shutter. Therefore, the shutter opening / closing mechanism 10 is applied to an imaging apparatus such as a video camera 1 as shown in FIGS. The number of points can be reduced, a gear box is not required, the lens barrel 5 can be reduced in size, and the degree of design freedom can be secured.

  The shutter opening / closing mechanism 10 rotates the inner shutter 12 and the outer shutter 13 between the open position and the closed position, so that the ring member 15 rotates the shutters 12 and 13 between the open position and the closed position. What is necessary is just to let an electric current flow into the coil 43 only for the very short time which rotates in the range required in order to move. Therefore, the shutter opening / closing mechanism 10 can perform the opening / closing operation with low power consumption without increasing the torque required for opening / closing the shutter.

  Further, the shutter opening / closing mechanism 10 brings the inner shutter 12 and the outer shutter 13 into the open position or the closed position by attracting the magnet 34 and one end 16a of the yoke 16 or attracting the magnet 35 and the other end 16b of the yoke 16. Can be held. Therefore, after the inner shutter 12 and the outer shutter 13 are rotated to the open position or the closed position, the shutter opening / closing mechanism 10 does not need to continue to supply current, and does not require power saving and unnecessary torque. Can be held in the open position or the closed position.

  Further, the shutter opening / closing mechanism 10 performs an opening / closing operation only by supplying a current for a very short time for rotating the ring member 15 in a predetermined range necessary for rotating the shutters 12 and 13. The rotational position of the outer shutter 13 is defined by abutting against a stopper wall standing on the surface 14a of the base plate 14, or by abutting the inner shutters 12 with each other. Therefore, in the shutter opening / closing mechanism 10, the rotation ranges of the shutters 12 and 13 are defined in advance, it is not necessary to control the current supplied to the coil 43, and a sensor for controlling the driving of a conventionally used motor is used. Etc. are also unnecessary.

  As shown in FIG. 6, the shutter opening / closing mechanism 10 may use a yoke 46 in which opposed surfaces 45, 45 are raised at both ends. In the present embodiment, the yoke 46 has a substantially rectangular plate shape, and a coil 47 is wound around an approximately central portion in the longitudinal direction via an insulating sheet, and both ends in the longitudinal direction are bent, whereby the magnet 34. , 35 facing each other.

  As shown in FIG. 7, the opposing surfaces 45, 45 have substantially the same height as the magnets 34, 35 by being erected from both ends of the yoke 46. As a result, the yoke 46 can apply a magnetic force over the entire magnets 34 and 35 to generate a large torque, reliably rotate the ring member 15 and rotate the shutters 12 and 13. The shutters 12 and 13 can be held in the open position or the closed position.

  Further, the opposing surfaces 45 and 45 are formed at substantially the same height as the magnets 34 and 35 by raising both ends of the yoke 46 in accordance with the heights of the magnets 34 and 35. Therefore, the yoke 46 can be made thinner and lighter than a configuration in which the yoke 46 is made thicker to obtain the same height.

  In addition, as shown in FIG. 8, the shutter opening / closing mechanism 10 is configured using a yoke 50 in which opposed surfaces 51, 51 are bent at both ends, and a ring member 52 provided with a pair of magnets 53, 54. May be. In the present embodiment, the ring member 52 is rotatably supported by the base plate 14 in the same manner as the ring member 15, and a pair of attachment pieces 55 a and 55 b project from the outer peripheral surface of the main body portion 55. Magnets 53 are provided on the attachment pieces 55a, and magnets 54 are provided on the attachment pieces 55b. The magnets 53 and 54 are arranged so that the same magnetic poles face each other. For example, as shown in FIG. 8, the N pole parts 53N and 54N are arranged to face each other. The yoke 50 has a substantially rectangular plate shape, and a coil 56 is wound through an insulating sheet in the approximate center in the longitudinal direction, and both ends in the longitudinal direction are bent, whereby a pair of opposing surfaces 51 and 51 are formed. Is formed. In the yoke 50, the tips of the pair of facing surfaces 51, 51 are attached to the back surface 14 b of the base plate 14, and magnets 53, 54 are disposed between the pair of facing surfaces 51, 51. The magnets 53 and 54 have the same magnetic pole, for example, S pole portions 53S and 54S, on the side facing the pair of opposed surfaces 51 and 51, respectively.

  In the embodiment shown in FIG. 8, the magnetic poles of the pair of facing surfaces 51 and 51 are reversed by changing the direction of the current flowing through the coil. Accordingly, the magnet 53 is attracted to the one opposing surface 51 and the magnet 54 is repelled from the other opposing surface 51 to rotate the ring member 52 in one direction, or the magnet 53 is attracted to the other opposing surface 51 and the magnet The ring member 52 can be rotated in the other direction by causing 54 to repel one of the opposing surfaces 51.

  In the embodiment shown in FIG. 8, the shutter opening / closing mechanism 10 is configured by one yoke 50 and a pair of magnets 53 by sandwiching a pair of magnets 53 between a pair of facing surfaces 51, 51 provided on the yoke 50. can do.

  Further, as described above, the shutter opening / closing mechanism 10 is provided with the yoke 16 on the base plate 14 and the magnets 34 and 35 on the ring member 15, and as shown in FIG. 61 may be provided, and the yoke 62 may be provided on the ring member 15. In this embodiment, a yoke 62 provided on the ring member 15 is disposed between two magnets 60 and 61 provided on the base plate 14. The two magnets 60 and 61 are arranged so that the magnetic poles on the opposite sides are the same. By passing a current through the yoke 62, one end of the yoke 62 and one magnet 60 facing the one end of the yoke 62 attract each other, and the other end of the yoke 62 and the other end facing the other end of the yoke 62 are attracted. As the magnet 61 repels, the ring member 15 is rotated in one direction. Further, by reversing the direction of the current flowing through the yoke 62, one end of the yoke 62 and one magnet 60 facing the one end of the yoke 62 are repelled, and the other end of the yoke 62 and the other end of the yoke 62 are repelled. The ring member 15 is rotated in the other direction by attracting the other magnet 61 facing the other. Also in this embodiment, the opposing surface may be formed by using a substantially rectangular plate-shaped yoke and bending both ends thereof.

  Further, as described above, the shutter opening / closing mechanism 10 includes two magnets on the base plate 14 and a yoke on the ring member 15, and a pair of magnets 65 and 66 on the base plate 14 as shown in FIG. 10. The pair of magnets 65 and 66 may be disposed between a pair of opposed surfaces provided on the yoke 67 of the ring member 15. In this embodiment, a coil is wound around the center of a substantially rectangular plate-shaped yoke 67 via an insulating sheet, and both ends of the yoke 67 are bent to provide a pair of facing surfaces. It is attached to a pair of attachment pieces protruding from the outer periphery. In addition, a pair of magnets 65 and 66 are attached to the base plate 14, and the pair of magnets 65 and 66 are disposed between a pair of opposed surfaces provided on the yoke 67. Also in this embodiment, by passing an electric current through the yoke 67, one opposing surface and one magnet 65 attract each other, and the other opposing surface and the other magnet 66 repel each other, so that the ring member 15 moves to the other. It is rotated. In addition, by reversing the direction of the current flowing through the yoke 67, one opposing surface and one magnet 65 repel each other, and the other opposing surface and the other magnet 66 attract each other, so that the ring member 15 becomes one. It is rotated.

  Furthermore, as shown in FIG. 11, the shutter opening / closing mechanism 10 may arrange one magnet 72 between a pair of yokes 70 and 71. In this embodiment, a pair of yokes 70 and 71 may be provided on the base plate 14 and one magnet may be provided on the ring member 15, or a pair of yokes 70 and 71 may be provided on the ring member 15 and one magnet may be provided. It may be provided on the base plate 14. The pair of yokes 70 and 71 are controlled so that the magnetic poles at the opposite ends sandwiching the magnet 72 are the same by controlling the direction of current. As a result, the pair of yokes 70, 71 has one end facing each other attracting the magnet 72 and the other end facing each other repels the magnet 72, so that the ring member can be rotated to one or the other. it can. Also in this embodiment, the opposing surface may be formed by using a substantially rectangular plate-shaped yoke and bending both ends thereof.

  As described above, the shutter opening / closing mechanism 10 is used not only for the lens barrier mechanism that is provided on the front surface portion of the lens barrel 5 and protects the imaging lens 6 but also for the shutter mechanism that controls the light incident on the imaging element. You can also.

DESCRIPTION OF SYMBOLS 1 Video camera, 2 apparatus main body, 5 lens barrel, 6 imaging lens, 8 strobe device, 10 shutter opening / closing mechanism, 11 front cover, 12 inner shutter, 13 outer shutter, 14 base plate, 15 ring member, 16 yoke, 20 Cover opening, 22 insertion hole, 23 support hole, 24 shaft hole, 26 base opening, 27 support pin, 29 shaft insertion hole, 30 rotation support piece, 31 support wall, 32 engagement support piece, 34 magnet, 35 magnet , 36 rotation shaft, 41 engagement hole, 43 coil, 45 facing surface, 46 yoke, 47 coil, 50 yoke, 51 facing surface, 52 ring member, 53 magnet, 54 body portion

Claims (5)

A shutter;
A base plate that supports the shutter in a pivotable manner and has an opening into which external light is incident; and
The base plate is rotatably supported, engages with the shutter, rotates in one direction to rotate the shutter in the opening direction of the opening, and rotates in the other direction to open the shutter in the opening. A ring member that rotates in the closing direction of the part,
The base plate and the ring member are provided such that either one of the pair of magnets is aligned with the opposite magnetic pole, and the other is disposed between the pair of magnets and has a coil at the center. A wound yoke is provided,
A shutter opening / closing mechanism that rotates the ring member by reversing the magnetic poles at both ends of the yoke by reversing the direction of the current of the coil and magnetically attracting or repelling the yoke and the pair of magnets.   The shutter opening / closing mechanism according to claim 1, wherein the yoke has a pair of opposing surfaces respectively opposed to the pair of magnets at both ends. The pair of magnets are provided on the ring member,
The shutter opening / closing mechanism according to claim 1, wherein the yoke is provided on the base plate. The pair of magnets are provided on the base plate,
The shutter opening / closing mechanism according to claim 1, wherein the yoke is provided on the ring member. A lens barrel including an imaging element and an imaging lens;
In an imaging apparatus provided with a shutter opening / closing mechanism that controls the incidence of light rays into the lens barrel,
The shutter opening / closing mechanism is
A shutter;
A base plate that supports the shutter in a pivotable manner and has an opening into which external light is incident; and
The base plate is rotatably supported, engages with the shutter, rotates in one direction to rotate the shutter in the opening direction of the opening, and rotates in the other direction to open the shutter in the opening. A ring member that rotates in the closing direction of the part,
The base plate and the ring member are provided such that either one of the pair of magnets is aligned with the opposite magnetic pole, and the other is disposed between the pair of magnets and has a coil at the center. A wound yoke is provided,
An imaging apparatus for rotating the ring member by reversing the magnetic poles at both ends of the yoke by reversing the direction of the current of the coil and magnetically attracting or repelling the yoke and the pair of magnets.

Images