JP4391264B2 - Camera blade drive - Google Patents

Description

  The present invention relates to a camera blade driving device in which a shutter device, a diaphragm device, a filter device, and the like are unitized as a single unit or a plurality of units.

  A lens shutter device (hereinafter referred to as a shutter device), a diaphragm device, and a filter device employed in a camera each have a blade member, and they are reciprocated by an actuator. In many cases, the shutter device has two shutter blades, but in the case of a camera having a small lens diameter, there is also one in which only one shutter blade is used. In addition, in the case of an aperture device used in a camera having a small lens aperture, a single aperture blade having a small circular opening is provided, and the opening is advanced and retracted as required in the imaging optical path. There is a lot going on.

  Further, in the case of the filter device, it has a shape similar to that of the above-described diaphragm blade (however, the opening may be substantially the same size as the photographing optical path regulating opening formed on the base plate) 1 In many blade members, a filter blade is formed by attaching an ND filter plate so as to cover the opening in the vicinity of the opening, but a blade member having such an opening is used. There is also a configuration in which two blade members are prepared, and between them, a blade member made only of the ND filter plate is overlapped, and the three blade members are simultaneously reciprocated in the same direction by the same angle. Yes. These shutter blades, aperture blades, and filter blades have recently been reciprocally operated by their respective actuators.

  In addition, the shutter device, the diaphragm device, and the filter device may be individually unitized, but these two or more devices may be a single unit. Furthermore, even in the case of unitization alone, in the case of a shutter device, the opening shutter blade and the closing shutter blade may be driven by separate actuators. In the case of a diaphragm device, a plurality of diaphragm blades having diaphragm openings of different sizes may be driven by different actuators. In the case of a filter device, a plurality of filters having different concentrations are used. The blades may be driven by separate actuators. In addition to the digital still camera, the digital video camera, the observation camera, the camera for the information terminal device including the portable device, the blade driving device unitized in this way is a conventional silver salt film camera or video. It can also be used in cameras.

  By the way, such units of various blade driving devices are configured by attaching many members directly or indirectly to one ground plane. In recent years, the base plate is made of a synthetic resin because it is advantageous for cost reduction and weight reduction. However, in addition to the various blades and motors for driving the blades as described above, it is necessary to attach a lens in some cases. There is a fact that it must be thick.

  On the other hand, recently, with the miniaturization of cameras, the reduction in thickness has been rapidly progressing, and there is a demand for disposing the photographing lens as close to the operating surface of the blade as possible. However, if the thickness of the ground plane is too large, it becomes difficult to meet such a requirement. In particular, in the case of a camera equipped with a solid-state image sensor, in order to reduce the thickness, a solid-state image sensor is arranged close to one surface of the blade driving device, and a photographing lens is arranged close to the other surface. However, in such a camera, in order to enlarge the imaging area as much as possible without increasing the lens aperture, the optical path of the imaging light with respect to the solid-state imaging device is regulated by being provided in the blade driving device. It is necessary to place the taking lens closer to the opening position. However, when the ground plane is thick, the thickness is inevitably limited.

Therefore, in order to eliminate such a restriction, a thin plate member (hereinafter referred to as an aperture restriction plate) is disposed on the surface of the ground plate on the solid-state imaging device side, and the aperture for imaging optical path regulation has its aperture restriction. It is formed on the plate, and a much larger opening is formed on the base plate so that a part of the photographing lens can be inserted, and the aperture for restricting the photographing optical path formed on the aperture restricting plate A configuration is known that is close to the portion (see Patent Document 1).
JP 2003-131285 A

  By the way, when the above-mentioned aperture restriction plate is provided in the camera blade driving device, the aperture restriction plate must be attached to the base plate, and the blade chamber is provided between the aperture restriction plate and the ground plate. A cover plate (also referred to as an auxiliary ground plate) for construction must also be attached to the ground plate. Further, when a plurality of blade chambers are configured, an intermediate plate (also referred to as a partition plate) disposed between the aperture regulating plate and the cover plate needs to be attached to the ground plate. However, in the past, when such a diameter regulating plate or cover plate was attached to the main plate, it was usually attached by a plurality of screws, which increased the number of parts and the number of assembly steps, which was extremely disadvantageous in terms of cost. there were. In addition, since the base plate is made of synthetic resin, there are those in which a diameter restricting plate is attached only by heating and deforming a part of it, but even when performing such heat welding, the number of parts is reduced. Because the work requires skill, it was not very effective in terms of cost.

  The present invention has been made to solve such problems, and the object of the present invention is to use the shape of the cover plate without using special mounting parts and without performing special processing. By devising the above, it is an object to provide a blade driving device for a camera that is extremely advantageous in terms of cost, and that allows the aperture regulating plate to be easily assembled to the base plate.

  In order to achieve the above object, a camera blade driving device according to the present invention is made of a synthetic resin base plate having an opening at a substantially central portion and a thin plate, and is substantially at the central portion. It has a circular optical path regulating opening smaller than the opening and centered on the optical axis, and is prevented from moving in a direction perpendicular to the optical axis by at least one positioning means provided on the base plate. The aperture restricting plate has an opening larger than the optical path restricting opening at a substantially central portion and has a plurality of bent pressing portions, and the aperture restricting plate is formed by the elasticity of the pressing portion. A cover plate that is attached to the base plate in a state of being pressed against the base plate and forms a vane chamber between the aperture restricting plate and the optical path regulating opening disposed in the vane chamber and reciprocated by a driving means Advancing and retreating to the club Kutomo and one blade, so that has a.

  In that case, the base plate has a plurality of engaging portions in the peripheral portion thereof, and the cover plate has a plurality of hook portions that are bent and elastic in the peripheral portion thereof, The cover plate is advantageous in terms of cost if it is attached to the base plate by hooking the hook portion to the engaging portion. Further, at least one of the positioning means is a shaft on which the blade is rotatably attached, and the aperture restricting plate is preferably formed with a hole that fits into the shaft. Become.

  In the camera blade drive device of the present invention, each of the blade chambers includes at least one blade, and a first blade and a second blade that are reciprocated by individual drive means are disposed. It is also possible to make it. In this case, if there is a concern that the first blade and the second blade may collide during operation, the optical path regulating opening is provided at a substantially central portion between the aperture regulating plate and the cover plate. An intermediate plate having an opening larger than the portion is disposed, and the intermediate plate constitutes a blade chamber of the first blade between the aperture restriction plate and the blade of the second blade between the cover plate and the cover plate. What is necessary is just to comprise a chamber.

  Since the camera blade drive device of the present invention includes a thin aperture plate in addition to a thick synthetic resin base plate, a part of the photographing lens can be inserted into an opening provided in the base plate. Although it is advantageous for thinning the camera configuration, when attaching the aperture restriction plate to the ground plate, it is not fixed to the ground plate, but when the cover plate is attached to the ground plate, Since it is made to press against the ground plane by the elasticity of multiple bent-shaped pressing parts formed on the plate, no special mounting parts are required, and no special processing steps are required. This is extremely advantageous.

  Embodiments of the present invention will be described with reference to the illustrated examples. 1 is a plan view of the embodiment, FIG. 2 is a side view seen from the right side of FIG. 1, and FIG. 3 is a cross-sectional view taken along line AA in FIG. In addition, the present invention can be a blade driving device in which the shutter device, the diaphragm device, and the filter device are individually unitized, or a blade driving device in which two of them are unitized. The embodiment is a blade driving device in which a shutter device and a diaphragm device are unitized. Furthermore, the present invention can be used as a blade driving device for a silver salt film camera or as a blade driving device for various digital cameras, but the embodiment is applied to a digital still camera. It is intended.

  First, the configuration of this embodiment will be described. The base plate 1 is made of a synthetic resin, and a circular opening 1a centering on the optical axis is formed in a substantially central portion. The ground plate 1 is a relatively thick member because many members including a motor need to be attached. Usually, the opening 1a formed in such a base plate 1 is often used as an opening for light path regulation (exposure opening), but in this embodiment, as described later, the optical path regulation is performed. Since the opening 1a is provided separately, the diameter of the opening 1a is larger than that of the opening for restricting the optical path, and a photographing lens (not shown) is disposed in the vicinity of the shutter blade and the diaphragm blade described later. It is possible to do. Accordingly, the shape of the opening 1a is not necessarily circular as in the present embodiment as long as the edge does not come into contact with the photographing lens.

  The base plate 1 is provided with two engaging portions 1b and 1c so as to protrude from the outer peripheral surface thereof. Further, as shown in FIG. 1, three shafts 1 d, 1 e, 1 f and one positioning pin 1 g are provided on one surface of the base plate 1, and the outer peripheral edge portion has the same shape. The four ridges 1h, 1i, 1j, and 1k are provided at equiangular intervals. Further, a plurality of stoppers for stopping the operation of each blade described later are provided on this surface, but these are not shown.

  The aperture regulating plate 2 is made of a thin metal plate material, and as can be seen from FIG. 1, the outer shape is substantially circular like the ground plate 1, but is slightly smaller than the ground plate 1 and its outer periphery. The surface is inside the four ridges 1h, 1i, 1j, and 1k. The aperture restricting plate 2 is formed with a circular opening 2a centered on the optical axis at a substantially central portion. The opening 2a has a diameter larger than that of the opening 1a of the main plate 1. It is quite small and serves as an opening for restricting the diameter of the optical path of the photographing light. In addition, the aperture regulating plate 2 is formed with three holes that are not labeled, and these are fitted to the shafts 1d, 1e, and 1f of the base plate 1. Further, a long hole 2b into which the positioning pin 1g of the base plate 1 is inserted is also formed.

  The cover plate 3 is made of a thin metal plate, and an opening 3a having a diameter larger than that of the opening 2a of the aperture restriction plate 2 is formed at a substantially central portion thereof. The cover plate 3 has two bent portions 3b and 3c bent at a predetermined angle from a circular outer peripheral edge at an angular position corresponding to the flanges 1i and 1k of the base plate 1. 1 has two bent portions 3d and 3e which are bent at a substantially right angle at a portion extended from the outer peripheral edge at an angular position corresponding to the ridges 1h and 1j. 2, the tip thereof is brought into contact with the aperture regulating plate 2, and the bent portions 3 d and 3 e are formed at the tip of the bent portion 3 e shown in FIGS. 2 and 3. The provided holes are latched to the engaging portions 1b and 1c of the main plate 1. Further, the cover plate 3 is formed with a hole which is not labeled, and is fitted to the shaft 1e of the base plate 1 described above. Further, a long hole 3f having the same shape is formed at a position corresponding to the long hole 2b of the aperture regulating plate 2, and a positioning pin 1g of the base plate 1 is inserted.

  Two shutter blades 4 and 5 and one diaphragm blade 6 are arranged in the blade chamber formed between the aperture regulating plate 2 and the cover plate 3 in this way. Among these three blades 4, 5, 6, the shutter blade 4 arranged on the most aperture regulating plate 2 side has a long hole 4 a and a shaft 1 e provided on the base plate 1. The other shutter blade 5 has a long hole 5 a and is rotatably attached to a shaft 1 d provided on the base plate 1. The diaphragm blade 6 arranged on the most cover plate 3 side has a long hole 6a and an opening 6b having a diameter smaller than the opening 2a for restricting the diameter, and is provided on the base plate 1 described above. The shaft 1f is rotatably attached.

  2, the right side surface of the base plate 1 has a complicated shape, and an actuator for reciprocatingly rotating the shutter blades 4 and 5 and an actuator for reciprocally rotating the aperture blade 6 are attached thereto. . The actuators M and M are current control type motors known as Japanese Patent Laid-Open No. 2000-29228, etc., which are called moving magnet type motors, etc., and correspond to the direction of energization to the stator coil. Thus, the permanent magnet rotor is a motor that reciprocates only within a predetermined angular range. Since the present invention is not directly related to the structure of such a motor, it is not shown so that the structure of the motor can be understood. However, only those rotors 8 and 9 are shown in FIG. It is shown.

  The rotors 8 and 9 pass through the respective output pins 8a and 9a through respective long holes (not shown) formed in an arc shape in the base plate 1 so that the opposite surfaces of the base plate 1, that is, the caliber. It protrudes on the surface where the restricting plate 2 is disposed. Although not shown in the drawings, the aperture restricting plate 2 is also formed with long holes having the same shape at positions facing the arc-shaped long holes formed in the base plate. Furthermore, arc-shaped notches 3g and 3h are formed in the cover plate 3 so as to correspond to the shape of a part of the long holes at positions facing the long holes. The output pin 8a is inserted into the long hole formed in the base plate 1 and the aperture regulating plate 2 and the long holes 4a and 5a formed in the shutter blades 4 and 5, and the tip of the output pin 8a is rotated when the rotor 8 rotates. It is made to go in and out of the notch part 3g formed in the cover board 3. As shown in FIG. The other output pin 9a is inserted into a long hole formed in the base plate 1 and the aperture restricting plate 2 and a long hole 6a formed in the aperture blade 6, and when the rotor 9 rotates, its tip is covered with the cover plate. It is made to go in and out of the notch 3h formed in 3.

  FIGS. 1 to 3 show a state after the assembly of the present embodiment is completed. Here, the aperture restriction plate 2, the shutter blades 3 and 4, the diaphragm blades 6, and the cover plate with respect to the base plate 1. 3 will be described. First, the aperture restriction plate 2 is attached to the base plate 1. In that case, three circular holes (not shown) provided in the aperture control plate 2 are fitted to the shafts 1d, 1e, and 1f of the base plate 1. The long hole 2b is fitted to the positioning pin 1g of the main plate 1. Accordingly, the aperture regulating plate 2 is regulated so that it cannot move in the direction orthogonal to the optical axis, and the output pin 8a is inserted into two long holes (not shown) formed in the aperture regulating plate 2. 9a are inserted.

  Thus, in this embodiment, the shafts 1d, 1e, and 1f of the base plate 1 and the positioning pins 1g serve as positioning means for the aperture regulating plate 2. However, such positioning is possible with only two of them, and in an extreme example, the cross-sectional shape of the positioning pin 1g is not circular but only the same shape as the long hole 2b. Is possible. Therefore, it is not necessary to limit the outer shape of the aperture restricting plate 2 to a circle as in the present embodiment, and various shapes can be selected. In the case of the present embodiment, the outer diameter of the aperture restricting plate 2 is circular, and the outer peripheral surface thereof is substantially in contact with the flanges 1h, 1i, 1j, 1k. In addition, the aperture regulating plate 2 can be positioned by adopting only one of the shafts 1d, 1e, 1f and the positioning pin 1g. In the case of the present embodiment, the aperture regulating plate 2 is made of metal. However, even if it is made thin, if each blade 4, 5, 6 can be operated smoothly, it can be made of synthetic resin. There is no problem.

  Next, two shutter blades 4 and 5 and one aperture blade 6 are attached. At this time, first, the hole (not indicated) of the shutter blade 4 is fitted to the shaft 1e, the output pin 8a is inserted into the long hole 4a, and then the hole (not indicated) of the shutter blade 5 is connected to the shaft 1d. The output pin 8a is inserted through the long hole 5a. Finally, the aperture (not indicated) of the aperture blade 6 is fitted into the shaft 1f, and the output pin 9a is inserted through the long hole 6a. In the case of this embodiment, as can be seen from the planar shape of each blade 4, 5, 6 in FIG. 1, even when only the shutter blades 4, 5 operate, only the aperture blade 6 operates. In addition, the overlapping state between the shutter blades 5 and the diaphragm blades 6 is always suitably maintained so that there is no possibility of collision. Therefore, in this embodiment, a known intermediate plate is arranged between the shutter blades 4 and 5 and the diaphragm blade 6 so that separate blade chambers need not be configured. In this embodiment, two shutter blades are used, but it goes without saying that the shutter blade 4 is unnecessary if there is no problem even if the planar shape of the shutter blade 5 is increased.

  Finally, the cover plate 3 is attached. In this case, a circular hole (not shown) provided in the cover plate 3 is fitted to the shaft 1 e of the base plate 1, and the long hole 3 f is fitted to the positioning pin 1 g of the base plate 1. Accordingly, the position of the cover plate 3 is restricted so that it cannot move in the direction orthogonal to the optical axis, but the bent portions 3b and 3c are in a normal state at that stage, The bending angle is as shown by a broken line in FIG. Further, the bent portions 3d and 3e are in the case of the bent portion 3e shown in FIG. 3, and their tips are located below the inclined surface of the engaging portion 1c, and the engaging portions 1c are not engaged. It does n’t match.

  In such a state, when the entire cover plate 3 is pushed to the ground plate 1 side, on the other hand, the bent portions 3b and 3c are deformed, and the diameter regulating plate 2 is pressed against the ground plate 1 by its elasticity. On the other hand, the bent portions 3d and 3e are deformed, and their tips climb up the slopes of the engaging portions 1b and 1c. Then, after the tips of the bent portions 3d and 3e have completely climbed the slope, the state where the holes (not indicated) are fitted to the engaging portions 1b and 1c by the elastic restoring force generated by the deformation is as follows. 1 and FIG. 2, the bent portions 3b and 3c are as shown by solid lines in FIG. Therefore, in this state, the aperture regulating plate 2 is in close contact with the ground plate 1 side due to the elasticity of the bent portions 3b and 3c of the cover plate 3. In this embodiment, the cover plate 3 is made of metal. However, the bent portions 3b, 3c, 3d, and 3e can have predetermined elasticity, and the mounting state to the ground plate 1 can be reliably obtained. If it is possible, it may be made of synthetic resin. In the present invention, since it is not essential to provide the bent portions 3d and 3e on the cover plate 3, as long as the bent portions 3b and 3c are provided, the base plate 1 can be attached by screwing or the like. There is no problem.

  Next, the operation of this embodiment will be briefly described. The blade driving device of this embodiment is configured to be suitable for use in a digital still camera, and FIG. 1 shows its initial state, that is, a photographing standby state. Therefore, at this time, since the shutter blades 4 and 5 have the opening 2a fully opened and the diaphragm blade 6 is in a state of being retracted from the opening 2a, the solid-state imaging device is exposed to the subject light. The image can be observed on a monitor. At this time, the motor coil is not energized, but as is well known, the stopped state of the rotors 8 and 9 is reliably maintained.

  When the release button is pressed at the time of shooting, it is determined depending on the measurement result of the photometry circuit whether shooting is performed with the shooting light amount reduced or not. When it is determined that photographing should be performed with the photographing light amount reduced, first, the motor for the aperture device is energized to rotate the rotor 9 clockwise. Therefore, the diaphragm blade 6 rotates counterclockwise, and when the center of the opening 6b reaches the optical axis position, the diaphragm blade 6 comes into contact with a stopper (not shown) provided on the base plate 1 and stops. Immediately thereafter, the charge accumulated in the solid-state image sensor is released, and imaging starts when new charge accumulation starts. Thereafter, when a predetermined time elapses, a motor for the shutter device is energized by a signal from the exposure control circuit, and the rotor 8 is rotated clockwise. Therefore, the shutter blades 4 and 5 are rotated in opposite directions, and immediately after closing the opening 2a, at least one shutter blade comes into contact with a stopper (not shown) provided on the base plate 1 and stops. .

  When the opening 2a is closed in this way, the imaging information is transferred to the storage device in that state. When the transfer is completed, the motor of the shutter device is energized in the opposite direction to the above case. Therefore, the rotor 8 rotates counterclockwise and causes the shutter blades 4 and 5 to open. When the shutter blades 4 and 5 are fully opened, at least one shutter blade comes into contact with a stopper (not shown) provided on the main plate 1 and stops immediately thereafter. After that, the motor of the diaphragm device is also energized in the opposite direction to the above case, so that the rotor 9 rotates counterclockwise and retracts the diaphragm blade 6 from the opening 2a. When the aperture blade 6 is completely retracted from the opening 2a, immediately after that, the aperture blade 6 comes into contact with a stopper (not shown) provided on the main plate 1 and stops. When the power supply to the two motors is cut off, the initial state shown in FIG. 1 is restored.

  On the other hand, in the case of shooting, the operation for shooting without reducing the shooting light quantity is only to reciprocate the shutter blades 4 and 5 in the above description of the operation. Therefore, in order to avoid duplication, description of the operation in that case is omitted. Moreover, although the above description of the operation has been described on the assumption that it is adopted in a digital still camera, the operation performed in this way is a case where it is adopted in another digital camera (a camera equipped with a solid-state imaging device). But basically the same. Further, when it is adopted in a silver salt film camera, the state in which the aperture blade 6 is in the position shown in FIG. 1 and the shutter blades 4 and 5 close the opening 2a is the initial state. The operation sequence is obvious to those skilled in the art and will not be described. In the above description of the operation, the stoppers of the shutter blades 4 and 5 and the diaphragm blade 6 have been described. However, if holes are formed in the aperture restricting plate 2 and these stoppers are fitted, these stoppers are also used. Similarly to the shafts 1d, 1e, 1f and the positioning pins 1g, the positioning means for the aperture restriction plate 2 can be used.

  In the case of the above embodiment, the shutter blades 4 and 5 and the diaphragm blade 6 are disposed in the same blade chamber. However, in the present invention, an intermediate plate is provided between the aperture regulating plate 2 and the cover plate 3. The shutter blades 4 and 5 and the aperture blade 6 may be arranged in separate blade chambers. In that case, the intermediate plate may be attached to the base plate by a dedicated attachment member. However, as in the case of the aperture restriction plate 2, the base plate 1 is provided with positioning means for the intermediate plate, and the cover plate 3 is provided. If the several bending part for intermediate | middle plates which has the same function other than said bending part 3b, 3c is provided, it will become a more excellent structure.

  In the case of the above embodiment, a current control type motor called a moving magnet type motor or the like is used as an actuator. However, the present invention provides other electromagnetics such as a step motor as a driving means. A drive means may be used. Further, the camera blade driving device of the embodiment is a unit in which the shutter device and the diaphragm device are unitized. However, the camera blade driving device of the present invention is a unit in which the shutter device, the diaphragm device, and the filter device are each independently provided. It may be a unitized one or two or more units.

It is a top view of an Example. It is the side view seen from the right side of FIG. It is the sectional view on the AA line in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ground plate 1a, 2a, 3a, 6b Opening part 1b, 1c Engagement part 1d, 1e, 1f Shaft 1g Positioning pin 1h, 1i, 1j, 1k 塀 2 Aperture control board 2b, 3f, 4a, 5a, 6a Long hole 3 Cover plate 3b, 3c, 3d, 3e Bent part 3g, 3h Notch 4,5 Shutter blade 6 Diaphragm blade 7,8 Rotor 7a, 8a Output pin

Claims (5)

  A synthetic resin base plate having an opening in the substantially central portion, and a circular optical path regulating opening that is manufactured in a thin plate shape and is smaller than the opening and centered on the optical axis in the substantially central portion. An aperture restricting plate that is prevented from moving in a direction perpendicular to the optical axis by at least one positioning means provided on the base plate, and an opening larger than the optical path restricting opening at a substantially central portion. And has a plurality of bent pressing portions, and is attached to the base plate in a state where the aperture restricting plate is pressed against the base plate by the elasticity of the pressing portion. A cover plate constituting a blade chamber; and at least one blade disposed in the blade chamber and reciprocated by a driving means to advance and retreat to the optical path regulating opening. Camera wings Drive.   The base plate has a plurality of engaging portions at the peripheral portion thereof, and the cover plate has a plurality of hook portions which are bent and elastic at the peripheral portion thereof, and the cover plate The camera blade driving device according to claim 1, wherein the hook portion is attached to the base plate by hooking the hook portion on the engaging portion.   2. The positioning device according to claim 1, wherein at least one of the positioning means is a shaft on which the blade is rotatably mounted, and the aperture restricting plate is formed with a hole fitted to the shaft. 3. A blade driving device for a camera according to 2.   The first blade and the second blade, each of which is composed of at least one blade and is reciprocated by individual driving means, are arranged in the blade chamber. The camera blade drive device according to any one of the above. An intermediate plate having an opening larger than the optical path restricting opening is disposed at a substantially central portion between the aperture restricting plate and the cover plate, and the intermediate plate is located between the aperture restricting plate and the first plate. 5. The camera blade drive device according to claim 4, wherein a blade chamber of one blade is formed, and a blade chamber of the second blade is formed between the blade chamber and the cover plate.