JP3569607B2 - Light control device - Google Patents

Description

[0001]
[Industrial applications]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light amount adjusting device including a light amount adjusting member that adjusts a light amount by movement and a driving unit that drives the light amount adjusting member in accordance with an input signal, and is used, for example, as a diaphragm device of a camera.
[0002]
[Prior art]
FIG. 8 shows a configuration example of a conventional light amount adjusting device.
According to this conventional example, a pair of diaphragm blades 3 and 4 as a light amount adjusting member are slidably supported on a base plate 1 serving as a support portion and covered with a diaphragm cover 2, and the diaphragm blades 3 and 4 are driven. It engages with a drive arm 7 which is connected to a shaft 6 which is the output shaft of the rotor 5 of the means.
The driving means is such that the rotor 5 is swingably included between the pair of coil frames 8a and 8b around which the coils are wound, the yoke 9 is fitted to the outside, and the bottom is covered by the cap 10. .
Conventionally, as shown in the figure, a supporting portion for supporting the light amount adjusting member is provided separately from the driving means.
[0003]
[Problems to be solved by the invention]
As described above, since the supporting portion of the light amount adjusting member is separate from the driving means as described above, the number of members is increased, the man-hour for assembling is increased, the cost is increased, and the assembling accuracy is reduced. In addition, there is a problem in miniaturization.
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the conventional product, and has as its object to provide a light amount adjusting device which has a reduced number of members as much as possible, is more compact, and has a remarkably excellent assembling man-hour and accuracy. It is intended.
[0004]
[Means for Solving the Problems]
The above object is achieved by the following configurations.
First, the invention of claim 1 includes a light amount adjusting blade for adjusting the light amount, a blade supporting member for movably supporting the light amount adjusting blade, a rotor formed of a magnet having a rotating shaft, and a rotor provided on the rotor. In an apparatus configuration including a drive arm for moving the light amount adjusting blade, a coil for forming a magnetic field outside the rotor, and a coil frame for winding the coil around the outer periphery, the blade supporting member may include the light amount adjusting blade. And a projection protruding from the flat surface and engaging with the light amount adjusting blade to restrict the movement thereof. The coil frame is composed of two coil frames divided vertically in the axial direction of the rotor, and one of the coil frames and the blade supporting member are formed by integral molding. Then, the drive arm is projected out of the coil frame and fitted into an engagement hole of the light amount adjusting blade supported on the flat surface. With such a configuration, one of the vertically divided coil frames and the blade supporting member having a flat surface for supporting the blades are integrally formed, so that the above-described problems such as miniaturization of the device can be achieved.
According to a second aspect of the present invention, there is provided a light amount adjusting blade for adjusting the light amount, a blade supporting member for movably supporting the light amount adjusting blade, a rotor formed of a magnet having a rotating shaft, and the rotor. In an apparatus configuration including a drive arm for moving the light amount adjusting blade, a coil for forming a magnetic field outside the rotor, and a coil frame for winding the coil around the outer periphery, the blade supporting member may include the light amount adjusting blade. And a projection projecting from the flat surface and engaging with the light amount adjusting blade to restrict the movement thereof. The coil frame is composed of two coil frames divided vertically in the axial direction of the rotor. Constitute. Then, one of the coil frames and the blade support member are formed by integral molding, and the rotor is incorporated by combining the two coil frames, and the coil is wound around the outer periphery of the combined coil frame. Then, the light amount adjusting blade is mounted on the flat surface of the blade supporting member around which the coil is wound, and the drive arm is projected outside the coil frame to be fitted into an engaging hole formed in the light amount adjusting blade. Further, the light amount adjusting blade is constituted by, for example, two blade members and is slidably supported on the flat surface.
[0005]
【Example】
Hereinafter, with reference to the drawings illustrating the embodiments of the present invention. FIG. 1 is a plan view of a first embodiment of a light amount adjusting device to which the present invention is applied, for example, a diaphragm device 20 of a camera. 2 is a sectional view of FIG. 1, and FIG. 3 is a bottom view of FIG. An aperture device (hereinafter, referred to as an aperture device) 20 of the camera is engaged with a drive motor 30 as a driving means and a drive arm 32 fixed to an output shaft 31 of the drive motor 30 as shown in each drawing. 5A and 5B, a pair of aperture blades 40 and 41 as a light amount adjusting member. By the way, the diaphragm blades 40 and 41 are formed of a very thin special metal material or the like, and cannot be held without supporting means. In the present invention include those having a major feature of the support means was integrated as part of the drive motor 30, in the illustrated embodiment, the coil frame 50 of the drive motor 30, in the perspective view of FIG. 6 As shown, the first coil frame 51 is divided into two parts by a plane orthogonal to the output shaft 31, and the second coil frame 60 is formed .
[0006]
FIG. 4 is a longitudinal sectional view of the first coil frame 51. The first coil frame 51 includes a frame body portion 52 and a support portion 53 having a flat surface that supports the diaphragm blades 40 and 41. As shown in the longitudinal sectional view 2 , the frame portion 52 is provided with a winding groove 521 for winding a coil (not shown). On the other hand, the support portion 53, the guide grooves 40a of the diaphragm blades 40, 41, 40b, 41a, the guide protrusions 531, 532, 533, 534 to fit in the guide such as 41b are projected, the blade in this projection Regulates the movement of people. Among them, the guide projections 532 and 534 are fitted with the guide grooves 40b and 41b, respectively, and bear not only the sliding guide in the side direction but also the guide in the facing direction of the guide portion 52. As shown in FIGS. 2 and 3, the second coil frame 60 has a substantially cylindrical shape, and includes a hollow portion 601 that rotatably accommodates a rotor 33 composed of a permanent magnet , which will be described later, and the first coil frame 60. A winding groove 602 corresponding to the winding groove 521 of the 51 coil, a support hole 603 for the shaft 31 of the rotor 33 described later, and the like are provided. Note that the second coil frame 60 is connected to the first coil frame 51 by screws 61. As shown, the second coil frame 60 also plays the role of a conventional cap.
[0007]
The rotor shaft 31 as an output shaft passes through the center of the rotor 33 and is integrated, and both ends of the shaft are defined by a support hole 522 of the first coil frame 51 and a support hole 603 of the second coil frame 60. , Is rotatably supported. Further, a drive arm 32 that protrudes outside the coil frame and engages with the aperture blades 40 and 41 to transmit a driving force is fixed to the rotor shaft 31 as shown in FIGS. The drive arm 32 is provided with a pair of engaging portions 32a and 32b which engage with the respective engaging holes 40d and 41d of the aperture blades 40 and 41. After the engaging portions 32a, 32b are respectively passed through the engaging holes 40d, 41d of the aperture blades 40, 41, holding members 34a, 34b for suppressing fluttering of the blades 40, 41 in a direction perpendicular to the plane are provided. It can be attached. The diaphragm blades 40 and 41 are supported in two directions perpendicular to the plane by two places by the holding members 34a and 34b and the guide protrusions 532 and 534 of the guide protrusions of the first coil frame 51, respectively. This eliminates the need for a member such as a large and large aperture cover, greatly contributing to member cost and space saving. The outermost part of the drive motor 30 is a cylindrical yoke 35 formed by winding a thin steel plate, and is fitted on the outer periphery of the second coil frame 60. The yoke 35 is partially formed with a notch 35a to determine the neutral position of the rotor 33 and thus the drive arm 32, that is, its home position when the coil is not energized. Is what it is.
[0008]
Next, the operation will be described.
First, the rotor shaft 31 and the drive arm 32 are combined, and then the drive arm 32 is fitted into and fixed to the rotor 33. At this time, the direction of the NS magnetic pole of the rotor 33 and the direction of the drive arm 32 are determined at a predetermined relationship. This is because the position of the drive arm 32 when power is not supplied is determined in relation to the position of the notch 35a of the yoke 35 later.
[0009]
Thereafter, the end of the rotor shaft 31 on the drive arm 32 side is inserted into the support hole 522 of the first coil frame 51, and the other end is inserted into the support hole 603 of the second coil frame 60. 60 is connected by a plurality of screws 61.
Next, a predetermined coil is wound around the coil winding grooves 521, 602 of the coil frames 50, 60. Normally, the coil is wound by being divided into a set of a driving coil and a braking coil at a slight interval, but is not shown.
Next, the yoke 35 is fitted along the outer periphery of the second coil frame 60 while paying attention to the direction of the notch 35a.
Next, the guide groove 40a of the diaphragm blade 40 is fitted to the guide protrusion 531 of the support portion 53, the guide groove 40b is fitted to the protrusion 532, and the groove 40c is engaged with the protrusion 534. On the other hand, the engagement groove 40d is engaged with the engagement portion 32a of the drive arm 32. Then, the holding member 34a is connected.
The aperture blade 41 is similarly engaged with the support portion 53 of the first coil frame 51 and the engagement portion 32b of the drive arm 32.
In addition, in addition to the above, a hall element or the like is incorporated in the hollow portion 601 of the second coil frame 60 as a sensor for detecting the rotational position of the rotor 33, and a terminal for supporting a terminal of the wound coil. Some have pins or the like, but details are omitted.
[0010]
The aperture device 20 assembled in this way is incorporated in front of a photosensitive means of a camera, for example, a CCD via a lens, and a current corresponding to luminance information of a subject is input to a drive coil, and the magnetic field generated by the drive coil The rotor 33 rotates, and the swing arm 32 swings to drive the aperture blades 40 and 41 to an appropriate opening position. However, the aperture blades 40 and 41 do not require a large base plate or an aperture cover as in the related art, and are configured to be extremely compact, so that the number of members is small and the size can be reduced. It can save space and contribute to cost reduction and downsizing of the camera.
[0011]
Next, FIG. 7 will be described with reference to a case where the coil frame 70 is divided into two right and left parts along the rotation axis of the rotor. In the drawing, the left and right coil frames are not shown for positioning, but are provided with a plurality of engaging projections on one side and an engaging concave portion on the other side on the mating surface. Therefore, in the following description, only the right side coil frame 70 in FIG. 7 will be described. In the coil frame 70, the frame body 71 and the supporting portion 72 for supporting the aperture blades 40 and 41 are integrally formed. A hollow portion 711 for accommodating the rotor 33 and a winding groove 712 for winding a coil are formed in the frame portion 71, and bearing holes 713a and 713b for supporting the rotor shaft 32 are provided. Have been. On the other hand, the support portion 72 is provided with two guide projections 721 and 722 on a flat surface supporting the diaphragm blades 40 and 41. Among them, the guide projection 721 on the side far from the drive motor 30 has a widened distal end so as to suppress fluttering of the diaphragm blade 40 or 41 in the support surface direction, and has a flat portion facing the diaphragm blade. The other members of the coil frame are formed in the same manner except that they are symmetrical, so that detailed description is omitted.
[0012]
Since the present embodiment is configured as described above, the drive motor 30 to which the drive arm 32 is attached is housed in the hollow portion 711, and the left and right coil frames 70 are combined. The explanation is omitted here.
Also in the second embodiment, as in the first embodiment, the total cost reduction effect by reducing the number of members and downsizing is enormous.
[0013]
【The invention's effect】
In the present invention, the coil frame for winding the coil is constituted by two coil frames divided vertically in the axial direction of the rotor, and one of the coil frames and the blade supporting member for supporting the light amount adjusting blade are formed by integral molding. In addition, the rotor built into the coil frame and the support portion (flat surface) of the blade can be brought close to each other, so that the device can be made compact and the manufacturing accuracy can be improved. At the same time, the number of parts and the number of assembling steps can be reduced, and a smaller and less expensive light amount adjusting device can be provided.
[0014]
[Brief description of the drawings]
FIG. 1 is a plan view of a diaphragm device of a camera.
FIG. 2 is a sectional view in FIG.
FIG. 3 is a bottom view of the aperture device of the camera. (Aperture blade omitted)
FIG. 4 is a longitudinal sectional view of a first coil frame of the coil frame in the first embodiment.
FIG. 5A is a plan view of one aperture blade.
FIG. 5B is a plan view of the other diaphragm blade.
FIG. 6 is a perspective view of the coil frame of the first embodiment.
FIG. 7 is an exploded perspective view of a coil frame according to a second embodiment.
FIG. 8 is an exploded view of a conventional empty stop device.
[Explanation of symbols]
20 Camera aperture device (light amount adjustment device)
30 Drive motor (drive means)
31 Rotor shaft (output shaft)
32 Drive arm (output arm)
33 Rotor 40 Aperture blade (light amount adjusting member)
41 Aperture blade (light amount adjusting member)
50 coil frame (first embodiment)
51 first coil frame 52 frame body (coil frame portion) (first embodiment)
53 Supporting part (first embodiment)
60 second coil frame 70 coil frame (second embodiment)
71 Frame Body (Coil Frame) (Second Embodiment)
72 Supporting part (second embodiment)

Claims (3)

A light amount adjusting blade for adjusting the light amount ,
A blade supporting member that movably supports the light amount adjusting blade ,
A rotor formed of a magnet having a rotation axis ,
A drive arm provided on the rotor for moving the light amount adjusting blade,
A coil forming a magnetic field outside the rotor;
In a light amount adjusting device having a coil frame around which the coil is wound,
The blade support member includes a flat surface that supports the light amount adjusting blade and a protrusion that projects from the flat surface and engages with the light amount adjusting blade to regulate the movement thereof,
The coil frame is composed of two coil frames divided vertically in the axial direction of the rotor,
And one and the blade supporting member of the coil frame so as to form by integral molding,
A light amount adjusting device, wherein the drive arm projects out of the coil frame and is fitted into an engagement hole of a light amount adjusting blade supported on the flat surface . A light amount adjusting blade for adjusting the light amount,
A blade supporting member that movably supports the light amount adjusting blade,
A rotor formed of a magnet having a rotation axis,
A drive arm provided on the rotor for moving the light amount adjusting blade,
A coil forming a magnetic field outside the rotor;
In a light amount adjusting device having a coil frame around which the coil is wound,
The blade supporting member includes a flat surface that supports the light amount adjusting blade and a guide protrusion that protrudes from the flat surface and engages with the light amount adjusting blade,
The coil frame is composed of two coil frames divided vertically in the axial direction of the rotor,
One of the coil frames and the blade support member are formed by integral molding,
The above-mentioned rotor is built by integrating the above-mentioned two coil frames,
The coil is wound around the outer periphery of the united coil frame,
The light amount adjusting blade is attached to a flat surface of a blade supporting member around which the coil is wound,
The light amount adjusting device, wherein the drive arm projects outside the coil frame and is fitted into an engagement hole formed in the light amount adjusting blade. The light amount adjusting device according to claim 1, wherein the light amount adjusting blade includes two blade members, and is slidably supported on a flat surface of the blade supporting member.

Images