JP4641891B2 - Camera blade drive - Google Patents

Description

  The present invention relates to a camera blade drive device in which blade members such as shutter blades, aperture blades, and filter blades are reciprocated in a blade chamber.

  As blade driving devices for cameras, there are a shutter device, a diaphragm device, a filter device, and a lens barrier device. Among them, the shutter device, the diaphragm device, and the filter device may be unitized independently, or two or more may be configured as one unit. In addition, each of these blade driving devices includes one or more blades. However, in the case of a blade driving device employed in a camera having a small lens aperture, the blade driving device includes one or two blades. It is normal. These blades are reciprocated by driving means, and the operation may be rotating or linear.

  Also, step motors and electromagnetic plungers may be used as driving means, but recently, current control type actuators called moving magnet type motors and the like are often used because of their low cost and easy size reduction. ing. Various configurations of this actuator are known mainly because of the difference in the configuration of the stator, but what is described in the following Patent Document 1 is suitable for thinning the device. Are known. Note that the actuator described in Patent Document 1 includes two yokes that are overlapped with each other. Further, the rotor has a permanent magnet magnetized in two (or four) poles in the radial direction regardless of the configuration of the stator. The blade can be reciprocated only in a predetermined rotation angle range in a direction corresponding to the energization direction of the coil, and the blade is reciprocated by at least one drive pin (also referred to as an output pin) integrated with the rotor. It is made to operate.

  Each unit as described above constitutes a blade chamber between the ground plate and the cover plate (sometimes referred to as an auxiliary ground plate), but when unitizing two or more devices, In order to prevent the blades of different devices from interfering with each other in operation, it is common to provide a plurality of blade chambers by providing an intermediate plate (sometimes called a partition plate) between the main plate and the cover plate. And what was made to do so is described in the following patent document 2. And recently, the base plate is almost made of synthetic resin, and a cover plate made of metal or synthetic resin is attached thereto.

  Also, as described in Patent Document 1, the actuator as the driving means is disposed outside the blade chamber between the ground plate and a cover member having a considerably smaller planar shape than the ground plate, and the rotor and The integral drive pin passes through a hole provided in the main plate and is connected to the blade in the blade chamber. In Patent Document 1, the cover member is attached to the base plate with two screws. However, since screw parts are disadvantageous in cost, only one screw is used, and the other screw is used as the base plate. It is also known to replace the hook part integrally formed with the hook.

  On the other hand, recently, focusing on the fact that the base plate is made of synthetic resin, a method of attaching a cover member by so-called thermal caulking has actually been adopted. In this mounting method, a shaft is provided on the surface of the main plate outside the blade chamber by integral molding, the shaft is passed through a hole provided in the cover member, and the protruding tip is thermally melted to be larger than the cross section of the shaft. A collar is formed to prevent the cover member from coming off. Therefore, according to this method, the cost can be reduced by the amount that does not require screw parts. In any of the attachment methods, the cover member is attached to the main plate at at least two places. The present invention relates to a camera blade drive device in which a cover member is suitably attached to a main plate.

JP 2004-309531 A Japanese Patent Laid-Open No. 2000-60088

  Recently, with the advent of digital cameras, the design of cameras has diversified, and since it has come to be installed in various portable information and communication devices, each of the blade drive devices as described above However, in order to be able to cope with them, there are increasing demands for downsizing and thinning. One method for reducing the size of the blade driving device is not simply to reduce the plane area of the ground plane, but to reduce the mounting area of the cover member, and as a result, to reduce the plane area of the ground plane. There is a way to do it. According to this method, even if the plane area of the main plate cannot actually be reduced so much due to the size and shape of the blades, at least the blades in the space generated by reducing the plane area of the cover member Other components of the driving device, components on the camera body side, and the like can be arranged, which is advantageous in terms of camera design.

  From this point of view, as an example, when the mounting structure of the cover member (bobbin and presser member 50) described in Patent Document 1 is viewed, the cover member has a planar shape centered on the optical axis. It is formed in an arc shape of a predetermined length, and both ends thereof are attached to the main plate with screws. In such a configuration, in order to reduce the plane area of the cover member, it is necessary to shorten the length of the cover member. However, in the shape of the base plate as it is, the position of one mounting portion is the yoke. It is difficult to move toward the rotor due to the arrangement of the other, and the position of the other mounting part cannot be moved toward the rotor due to the through hole of the drive pin being formed in the main plate It is.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a blade driving device in which an actuator rotor is disposed between a main plate and a cover member outside the blade chamber. In this case, the blade driving device for a camera is advantageous for downsizing, in which the mounting shaft of the cover member can be erected at the hole forming position even though the hole through which the driving pin of the rotor is formed is formed in the base plate. Is to provide.

In order to achieve the above object, the present invention has at least one blade disposed in at least one blade chamber formed between a base plate having an opening for a photographing optical path and a cover plate, Outside the blade chamber, an actuator is disposed between the main plate and a cover member having a smaller planar shape than the main plate, and the main plate is integrated with the rotor of the actuator and has a predetermined rotation angle of the rotor. In the blade driving device having a through hole for enabling a drive pin that reciprocates only within the range to be connected to the blade in the blade chamber, the base plate is made of synthetic resin, and outside the blade chamber, has an empty only且 one said overhanging portion partially formed so as to cover the through-hole a predetermined gap between the through hole, the該庇portion, provided on said cover member hole The shaft to be fitted to the So as to.

  In that case, if the said collar part and the said cover member are directly contacting, the arrangement position of both will become more stable. In addition, the cost of the shaft can be reduced if the tip portion of the shaft penetrates the hole of the cover member and is formed in a planar shape larger than the cross section of the shaft portion by heat melting. Further, the cover member is made of synthetic resin and forms a bobbin portion having a hollow portion, and the rotor of the actuator is perpendicular to the surface between the base plate and the cover member. The rotor is made of a permanent magnet that is rotatably arranged on the shaft, and the stator of the actuator is opposed to the rotor by forming a coil wound around the bobbin portion and a substantially U-shape. If the two magnetic pole portions are provided and one of the magnetic pole portions is composed of a yoke inserted into the hollow portion of the bobbin portion, the apparatus can be thinned.

  The present invention relates to a camera blade driving device in which a rotor of an actuator is disposed between a base plate and a cover member outside a blade chamber, and a through hole of a driving pin integral with the rotor is formed in the base plate. The base plate is formed with a flange portion that covers the through hole so as to have an interval for enabling the operation of the drive pin between the through hole, and a shaft for attaching the cover member to the flange portion. Since the shaft is moved closer to the rotor than in the prior art, the planar shape of the cover member can be reduced by that amount, and the entire blade driving device is reduced in size. It becomes possible.

  Embodiments of the present invention will be described with reference to the examples shown in FIGS. The camera blade driving device of the present invention can be applied to any of a shutter device, a diaphragm device, a filter device, and a lens barrier device. Further, the present invention can also be applied to a device in which two or more of the shutter device, the diaphragm device, and the filter device are configured as one unit. Furthermore, these devices can be employed in cameras using silver salt films, and can also be employed in digital cameras including various information terminal equipment cameras and video cameras. However, since there is no need to describe all of these cases with specific examples, as an embodiment, a shutter device effective as a unit for a small digital camera or an information terminal device camera is unitized. explain.

  This embodiment is configured as a shutter device having a single blade. 1 is a perspective view of the present embodiment, FIG. 2 is a plan view, and FIG. 3 is an exploded perspective view. 4 is a cross-sectional view taken along line AA in FIG. 2, FIG. 5 is a plan view showing only the ground plane, and FIG. 6 is a cross-sectional view taken along line BB in FIG.

  First, the configuration will be described. The ground plane 1 of the present embodiment is made of synthetic resin and is formed relatively thick, and the planar shape is rectangular. As shown in FIG. 5, it has a circular opening 1a for the photographing optical path, and an arc-shaped long hole 1b corresponding to the through hole of the present invention is formed at the position in the upper right direction. ing. In the present embodiment, the cover plate 2 having an outer shape substantially the same size as the main plate 1 is also made of synthetic resin, and a blade chamber is formed between the cover plate 2 and the main plate 1. An opening 2a having a diameter slightly larger than that of the opening 1a is formed at a position facing the opening 1a, and a length having substantially the same shape is formed at a position facing the long hole 1b. A hole 2b is formed.

  Five shafts 1c, 1d, 1e, 1f, and 1g are erected on the surface of the main plate 1 on the blade chamber side. Among these, the shafts 1c, 1d, 1e, and 1f are attached to the cover plate 2. It is an axis for. On the other hand, the surface on the blade chamber side of the cover plate 2 has five holes 2c, 2d, 2e, 2f, which are fitted with the shafts at positions facing the shafts 1c, 1d, 1e, 1f, 1g. Although 2g is provided, only the hole 2c provided at the position opposed to the shaft 1c is not shown in the drawing. Of these, the holes 2 c, 2 d, 2 e, 2 f are formed in a thick portion for maintaining a predetermined distance from the ground plane 1. The cover plate 2 is attached to the base plate 1 by melting the tips of the shafts 1c, 1d, 1e, and 1f penetrating the holes 2c, 2d, 2e, and 2f into a bowl shape by heat melting. . 3 and 6, these axes are shown in a state before the tip portion is deformed into a bowl shape.

  Thus, the shutter blade 3 is arranged in the blade chamber formed between the main plate 1 and the cover plate 2. The shutter blade 3 is formed with a circular hole 3a and a long hole 3b, and the hole 3a is rotatably fitted to the shaft 1g. In the normal case, a shaft-like stopper is often provided on the surface of the base plate 1 on the blade chamber side. However, in the case of this embodiment, such a stopper is provided for the reason described later. Not provided. However, there is no problem even if such a stopper is provided. In the case of providing such a stopper, as is well known, a hole for inserting the tip of the cover plate 2 is formed.

  As can be seen from FIG. 3, the surface outside the blade chamber of the base plate 1 has a complicated shape, and three depressions 1 h, 1 i, 1 j lower than the reference surface 1 ′ and one ridge higher than the reference surface 1 ′. A portion 1k is formed, and the opening 1a and the long hole 1b are formed in the recessed portions 1h and 1i. A shaft 1m is erected on the reference surface 1 ', and a shaft 1n is erected on the recess 1i. Further, a ridge projecting from the raised portion 1k so as to obtain a predetermined distance from the surface of the hollow portion 1i where the long hole 1b is formed and covering a part of the long hole 1b. A (eave) portion 1p (see FIG. 5) is provided, and a shaft 1q is erected there. And the actuator is attached to the surface outside the blade chamber of the base plate 1 which has such a shape.

  As already described, the actuator of this embodiment is a current control type motor called a moving magnet type motor or the like. This motor is a motor that rotates a rotor having a permanent magnet in a direction corresponding to the energization direction to the stator coil only within a predetermined angle range. Various types of motors of this type are known mainly because of the difference in the configuration of the stator. Among them, the motors used in this embodiment are thinner devices. In general, it is said to be a flat motor or the like.

  First, the rotor 4 of this embodiment has a cylindrical permanent magnet 4a magnetized in two radial directions, and is rotatably attached to the shaft 1n. A synthetic resin arm 4b that is integrated with the permanent magnet 4a and projects in the radial direction is provided with a drive pin 4c at the tip thereof. Then, when the rotor 4 is assembled, the drive pin 4c is inserted into the elongated hole 1b from a portion not covered with the flange portion 1p. After the assembly, the arm 4b is inserted into the hollow portion 1i. It can operate between the formation surface of the long hole 1b and the flange 1p. The drive pin 4c is inserted into the blade chamber through the long hole 1b and fitted into the long hole 3b of the shutter blade 3, and the tip protruding from the long hole 2b of the cover plate 2 to the outside of the blade chamber is caused by heat melting. The cover plate 2 is deformed into a bowl shape so as not to come into contact with the cover plate 2 so as not to come out from the elongated hole 2b to the blade chamber side.

  The cover member 5 of the present embodiment is made of a synthetic resin and has a hollow bobbin portion 5a around which a coil 6 is wound. Further, the yoke 7 having a substantially U-shape and having two leg portions has one leg portion inserted into the hollow portion of the bobbin portion 5a, and the tip ends of the two leg portions are magnetic poles. As a part, it is made to oppose the surrounding surface of the permanent magnet 4a. Further, the cover member 5 has holes 5b and 5c, the yoke 7 has a hole 7a, the hole 5b of the cover member 5 and the hole 7a of the yoke 7 are fitted to the shaft 1m of the base plate 1, and the cover The hole 5c of the member 5 is fitted to the shaft 1q of the main plate 1. In this state, the tips of the shafts 1m and 1q protrude from the holes 5b and 5c of the cover member 5, and the tip surface of the shaft 1n is in contact with the cover member 5 as shown in FIG. It is in a state close to. Further, a part of the bobbin portion 5a and the coil 6 are contained in the above-mentioned hollow portion 1j. The cover member 5 is attached to the main plate 1 by melting the tips of the shafts 1m, 1q into a bowl shape larger than the holes 5b, 5c. In FIGS. 3 and 6, the ends of the shafts 1m and 1q are not deformed in a bowl shape.

  As described above, in the case of the present embodiment, the rotor 4 is rotatably attached to the shaft 1 n that is erected on the main plate 1. However, a shaft corresponding to the shaft 1n may be erected on the cover member 5 and the rotor 4 may be attached to the shaft. In addition, the permanent magnet 4a of the present embodiment is formed in a cylindrical shape having a through-hole to be fitted to the shaft 1n. Thus, it may be supported by the main plate 1 and the cover member 5. As is well known, the entire rotor 4 may be made of permanent magnets.

As can be seen from the configuration of this embodiment, the shutter device of this embodiment can be made smaller than the conventional shutter device. That is, in the conventional case, the base plate 1 is not provided with the flange portion 1p. Therefore, when the shaft 1q is provided, it is erected on the right side of the long hole 1b in FIG. Become. However, when standing on the right side of the long hole 1b, obviously, the base plate 1 and the cover member 5 have to be enlarged to the right side. Moreover, when standing upright, the space for the shaft 1q itself can be secured, but since the tip must be deformed into a bowl shape by heat melting, at least the cover member 5 must be enlarged upward. Disappear. Further, if the cover member 5 is to be attached by screwing, the shaft 1q must be thickened and the head of the screw is large, so that both the base plate 1 and the cover member 5 have to be enlarged upward. On the other hand, in the present embodiment, the shaft 1q is erected on the flange portion 1p. Therefore, as can be seen from FIG. so that the need not to increase the and the cover member 5. Further, from this, the shaft 1q can be thickened and screwed.

  In the above configuration of the present embodiment, the bobbin portion 5a is provided in the cover member 5, but the cover member 5 may be a plate-like member and the bobbin may be an independent member. Further, the shaft 1m is formed to be thinner than the shaft for screwing in order to attach the cover member 5 by thermally melting the tip thereof. Therefore, in this embodiment, the shaft 1m also serves as a positioning pin for the yoke 7. However, the present invention is not limited to such a configuration, and the cover plate 5 may be configured to be screwed. There is no problem. In that case, as described in Patent Document 1, the shafts are provided separately. However, if configured as in the present embodiment, only a relatively thin shaft 1 m is required, which is advantageous in reducing the planar area of the cover member 5. In the present embodiment, the tip of the shaft 1q is also melted by heat to attach the cover member 5. However, the present invention is not limited to such a configuration, and as described above, the shaft 1q is thickened. Then, it can be screwed. However, the configuration as in the present embodiment is advantageous from the viewpoint of cost reduction.

  Next, the operation of this embodiment will be described. FIG. 2 shows a photographing standby state, and the opening 1a is fully opened. At this time, the coil 6 is not energized. However, as is well known, at this time, the rotor 4 is rotated counterclockwise by the magnetic attractive force acting by the opposing arrangement relationship between the magnetic pole of the permanent magnet 4a and the two magnetic pole portions of the yoke 7. The shutter pin 3 is rotated counterclockwise by the drive pin 4c, but the drive pin 4c is pressed against one end in the length direction of the long hole 1b, and this state is maintained. Yes. That is, in the present embodiment, both ends of the long hole 1b in the length direction are used as stoppers without providing a dedicated stopper on the base plate 1. In this state, the photographer can observe the subject image via a liquid crystal display device or the like.

  When the release button is pressed during shooting, exposure for shooting is started by releasing the charge accumulated in the solid-state imaging device until then. When a predetermined time elapses, a forward current is supplied to the coil 6 by a signal from the exposure time control circuit. Therefore, the rotor 4 rotates clockwise, and the shutter blade 3 is rotated clockwise by the drive pin 4c. As a result, the shutter blade 3 closes the opening 1a and is stopped by the drive pin 4c coming into contact with the other end of the long hole 1b immediately after the opening 1a is completely closed.

  As described above, when the opening 1a is in the closed state, the imaging information is transferred to the storage device, and when the transfer ends, a current in the reverse direction is supplied to the coil 6 this time. Therefore, the rotor 4 is rotated counterclockwise, and the shutter blade 3 is rotated counterclockwise by the drive pin 4c. Thereby, the shutter blade 3 is stopped by the opening of the opening 1a and immediately after the shutter blade 3 is fully opened, the drive pin 4c comes into contact with one end of the long hole 1b. And the state which interrupted the electricity supply with respect to the coil 6 is the imaging | photography standby state shown by FIG.

  Although this embodiment is configured as a shutter device in which one shutter blade is reciprocatingly rotated, as is well known, the present invention reciprocates two shutter blades simultaneously in opposite directions. It can also be configured as a shutter device that is rotated. In addition, the shutter device having such a configuration and the shutter device of the present embodiment can be employed as a lens barrier device with almost the same configuration. In addition, the present invention can also be used as a diaphragm device by forming a circular opening smaller than the opening 1a in the shutter blade 3 of the present embodiment, and the opening formed in the shutter blade 3 It is also possible to provide a filter device by attaching an ND filter plate. Furthermore, in the present invention, one or a plurality of blade chambers are formed between the base plate and the cover plate, so that two or more of the shutter device, the diaphragm device, and the filter device as described above are configured as one unit. In this case, two or more actuators are provided on a common ground plane.

It is a perspective view of an Example. It is a top view of an Example. It is a disassembled perspective view of an Example. It is the sectional view on the AA line of FIG. It is a top view of the main plate in an example. FIG. 6 is a sectional view taken along line B-B in FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ground plane 1 'Reference surface 1a, 2a Opening part 1b, 2b, 3b Long hole 1c, 1d, 1e, 1f, 1g, 1m, 1n , 1q Axis 1h, 1i, 1j Recessed part 1k Protruding part 1p Eaves part 2 Cover board 2c, 2d, 2e, 2f, 2g, 3a, 5b, 5c, 7a hole 3 shutter blade 4 rotor 4a permanent magnet 4b arm 4c drive pin 5 cover member 5a bobbin portion 6 coil 7 yoke

Claims (4)

At least one blade is disposed in at least one blade chamber formed between the ground plate having the opening for the photographing optical path and the cover plate, and is more planar than the ground plate and the ground plate outside the blade chamber. An actuator is disposed between the cover member and the cover plate, and the main plate includes a drive pin that is integral with the rotor of the actuator and that reciprocates only within a predetermined rotation angle range of the rotor within the blade chamber. in it are blade drive device has a through hole for enabling connection to the vane, wherein the base plate is made of synthetic resin, in vane outdoor, after a short predetermined gap between the through-hole 且 One said has a visor portion which as part cover to formed of the through hole, the該庇part, that the shaft fitting into a hole provided in said cover member is provided upright Characteristic blade drive device for camera   The camera blade driving device according to claim 1, wherein the flange portion and the cover member are in direct contact with each other.   3. The shaft according to claim 1, wherein a tip portion of the shaft passes through a hole of the cover member and is formed in a planar shape larger than a cross section of the shaft portion by heat melting. Camera blade drive device.   The cover member is made of synthetic resin and forms a bobbin portion having a hollow portion, and the rotor of the actuator is on an axis perpendicular to the plane between the main plate and the cover member. The rotor of the permanent magnet is arranged so as to be able to rotate, and the stator of the actuator is opposed to the rotor by forming a coil wound around the bobbin portion and a substantially U shape. 4. The blade driving device for a camera according to claim 1, comprising: a yoke having two magnetic pole portions and one magnetic pole portion being inserted into a hollow portion of the bobbin portion. 5. .