JPH0950065A - Driving device for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving device for camera reduced in the thickness in the optical axial direction and the cost. SOLUTION: The rotator 7 of a motor provided with a permanent magnet 7a and speed reduction gears 9 and 10 are releasably supported by a base plate 1 and a frame member 5, respectively. An iron core member 6 having a coil 6d wound on one leg part 6d is attached to the frame member 5 by a hook part 5d, in such a manner that a pin 5c is fitted into the hole 6a of the member 6 and the top ends of respective leg parts 6d (6c) are inserted into holes 5f separately provided in the frame member 5, so that the end surface of the leg parts 6b (6c) face the periphery of the rotator 7. Its rotation is transmitted to a driving ring 4 with an output gear 8 and the speed reduction gears 9 and 10 to execute the opening control of a diaphragm aperture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera incorporated in a camera, which is suitable for electrically opening and closing a shutter, adjusting an aperture of a diaphragm, moving a lens when adjusting a distance, and changing a magnification. Drive device.

[0002]

2. Description of the Related Art Recent cameras are required to be compact and low in cost, but on the other hand, it is required to be able to electrically perform the above-mentioned operations. Therefore, these drive devices must be configured so that the mounting area is as small as possible with respect to the board, the number of parts is small, and the board surface is not bulky. In such a demand, in arranging the drive device at the side position of the optical axis, in order to make the dimension in the radial direction with respect to the optical axis as small as possible and to make the optical axis thin, It is known to use a motor that can be arranged in an arc shape around the optical axis, and many proposals have been made, including those disclosed in Japanese Utility Model Laid-Open No. 1-116583.

In this type of motor, the legs of an iron core (yoke) member around which a coil is wound are arranged so as to face a part of the peripheral surface of a magnetized rotor. The rotor and the iron core member can be attached to the substrate once between the two frame members and then to the board, or when one of the frame members is omitted and the board and the other frame member are attached. In some cases, the latter mounting configuration is advantageous when it is desired to make the substrate surface thin and not bulky.

By the way, in using such a type of motor in a camera, a reduction gear mechanism is generally required. Therefore, when the motor of the latter mounting configuration described above and this reduction gear mechanism are arranged on the same surface of the substrate, at least the rotation shaft of the reduction gear is provided between the reduction gear and the iron core (yoke) member. In order to support, it is necessary to interpose a support plate. Such an example will be described with reference to FIG. Since this figure is a cross-sectional view, it is difficult to understand the planar arrangement. However, since it is a figure cut in the same manner as FIG. 2 used to describe the embodiment, an unclear plan configuration will be described in the embodiment. It is possible to make an analogy with the comparison with FIG.

FIG. 5 shows a driving device for adjusting the aperture opening. A blade chamber is formed between a substrate 31 and a cover plate 32, and three diaphragm blades 33 (only one is shown).
Is housed. The drive ring 34 is rotatably arranged around the optical axis, and its pin 34a penetrates a hole 31a formed in an arc shape around the optical axis and a circular hole formed in the diaphragm blade 33. , Its tip is fitted in a groove 32a formed in the cover plate 32 in an arc shape. The pin 33 a of the diaphragm blade 33 is fitted in the cam groove 32 b formed in the cover plate 32.

A support plate 35 is fixed to the base plate 31 by screws 36, and the pin 31b is included in the meaning including a rotation stop.
Are fitted into the holes of the support plate 35. One iron core member 37 is placed on the support plate 35. The iron core member 37 is fitted in the pin 35a, and the coil 37a is wound around the leg portion thereof. The other iron core member 38 is
A coil 38a is wound around the leg portion, is placed on the substrate 31 so that the horizontal position is the same as the iron core member 37, and is attached to the substrate 31 by a screw (not shown). The frame member 39 is made of synthetic resin, and the flexible hook portion 39a is engaged with the engaging portion 35b, the iron core member 37 is attached to the support plate 35, and the iron core member 38 is attached to the substrate 3.
It is attached to the support plate 35 so as to be pressed against the base plate 1. The pin 35a is fitted in the hole 39b.

A rotor 40 having a permanent magnet 40a is rotatably supported by the substrate 31 and the frame member 39, and is arranged so that its peripheral surface faces the end surfaces of the legs of the iron core members 37 and 38. Further, an output gear 11 is integrally formed on the rotor 10. Reduction gears 4 meshing with each other
2 and 43 are respectively supported by the base plate 31 and the support plate 35, the reduction gear 42 is the output gear 41, and the reduction gear 4 is
Reference numeral 3 meshes with a tooth portion 34b of the drive ring 34. Therefore, with this configuration, the rotation of the rotor 40 is decelerated and transmitted to the drive ring 34, and when the rotor 40 rotates in one direction, the aperture opening is enlarged, and when it is rotated in the opposite direction, it is reduced. Is able to.

[0008]

However, in the structure in which the support plate is provided as described above, a space is required at least by the thickness dimension of the support plate in the optical axis direction (vertical direction in FIG. 5). It is extremely disadvantageous in reducing the thickness of the entire device in the optical axis direction, and its existence is also disadvantageous in terms of cost in terms of the number of parts and the number of assembling steps, and structural improvement measures for these points are required. It had been.

The present invention has been made in order to solve such a point, and an object of the present invention is to provide a reduction gear with a motor rotor without providing a conventional support plate. The purpose of the present invention is to provide a camera drive device that can be made thin and low in cost by supporting the frame member and the substrate. Another object of the present invention is to provide a camera in which an iron core member can be easily assembled on the surface opposite to the surface on which the frame member supports the reduction gear after the rotor and the reduction gear are assembled. A drive device for a vehicle is provided.

[0010]

In order to achieve the above object, a camera driving device of the present invention is arranged such that a rotor having a permanent magnet and a peripheral surface of the rotor are opposed to each other at a predetermined interval. An iron core member having a plurality of leg portions formed by winding a coil around at least one leg portion, an output gear that rotates integrally with the rotor, and a rotation shaft of itself that meshes with the output gear. At least one reduction gear that has one end thereof supported by a substrate and transmits the rotation of the rotor to a driven member, and is mounted on the substrate and surrounds at least the rotor between the reduction gear and the reduction gear. A frame member supporting the other end of the rotating shaft. With this configuration,
It is possible to reduce the thickness of the drive device as a whole and to reduce the cost.

Also, in the camera drive device of the present invention, preferably, the iron core member is mounted on the surface of the frame member opposite to the surface supporting the rotation shaft of the reduction gear. With this structure, the iron core member can be easily assembled in the final stage of the assembly operation of the entire drive device. Further, in the camera drive device of the present invention, preferably, the frame member is provided with a restriction portion for disposing the leg portion of the iron core member at a predetermined facing position with respect to the peripheral surface of the rotor. To do so. With this configuration,
Positioning of the rotor already assembled and the iron core member assembled at the final stage becomes easy.

[0012]

EXAMPLE An example of the present invention will be described with reference to FIGS. The present embodiment is an example in which the present invention is applied to an automatic diaphragm device for a single-lens reflex camera, FIG. 1 is a plan view showing a minimum diaphragm aperture state, and FIG. 2 is a partially expanded state of a main part of FIG. 4 is a cross-sectional view shown in FIG. 3, and FIG. 3 is a plan view showing a state where the diaphragm is fully opened.

First, the configuration of this embodiment will be described with reference to FIGS. 1 and 2. A circular opening 1a is formed around the optical axis at the center of the substrate 1 having a substantially circular outer shape. A cover plate 2 having substantially the same outer shape is attached to the back side of the substrate 1, and an opening (not shown) having substantially the same shape as the opening 1a is formed in the central portion of the cover plate 2. The subject light is introduced into the camera through these openings. A blade chamber is formed between the substrate 1 and the cover plate 2 and accommodates three diaphragm blades 3.

The drive ring 4 is rotatably arranged on the substrate 1 about the optical axis, and the three pins 4a are holes 1b formed in the substrate 1 in an arc shape about the optical axis, respectively. It penetrates through a circular hole formed in each diaphragm blade 3, and its tip is fitted in a groove 2 a formed in the cover plate 2 in an arc shape. The pin 3a of the diaphragm blade 3 is fitted in the cam groove 2b formed in the cover plate 2. The frame member 5 is made of synthetic resin, and is attached to the substrate 1 by engaging the flexible hook portions 5a with the engaging portions 1c of the substrate 1 at two locations. In addition, the pin 1d of the substrate 1 for positioning
Is fitted in the hole 5b of the frame member 5.

Two iron core members 6 are mounted on the frame member 5. Each iron core member 6 is attached by a hook portion 5d with a hole 6c fitted in a pin 5c. Each iron core member 6 has two leg portions 6b and 6c, and a coil 6d is wound around each leg portion 6b. A cylindrical portion 5e is formed on the frame member 5, and the leg portions 6 of each iron core member 6 are formed.
Each of b and 6c has its tip portion inserted into a hole 5f provided individually in the cylindrical portion 5e.

Rotor 7 having permanent magnet 7a of four-pole structure
Are supported by the substrate 1 and the frame member 5, and are arranged so that the peripheral surfaces thereof face the end surfaces of the legs 6b and 6c of the iron core members 6. An output gear 8 is formed integrally with the rotor 7. The reduction gears 9 and 10 meshing with each other are respectively supported by the substrate 1 and the frame member 5, and the bearing portion for the frame member 5 is one iron core member 6
(The iron core member on the right side in FIG. 1) is on the opposite side of the mounting position. The reduction gear 9 meshes with the output gear 7, and the reduction gear 10 meshes with the tooth portion 4b of the drive ring 4. Therefore, with this configuration, the rotation of the rotor 7 is decelerated and transmitted to the drive ring 4, and when the rotor 7 rotates in one direction, the aperture opening is enlarged, and when it is rotated in the opposite direction, it is reduced. Is able to.

Next, the operation of this embodiment will be described. As described above, this embodiment is an automatic diaphragm device for a single-lens reflex camera. In the case of such a diaphragm device, when the camera is not used, it is usual to narrow the diaphragm blade 3 as much as possible as a measure for preventing light leakage from the focal plane shutter. FIG. 1 shows such a state, and most of the openings 1a are closed by the three diaphragm blades 3 and the minimum opening state is achieved. Therefore, when the power switch is closed prior to photographing, pulse current is supplied to the coils 6a of the two iron core members 6 as is well known.
The rotor 7 rotates clockwise.

The clockwise rotation of the rotor 7 is transmitted to the drive ring 4 via the output gear 8 and the reduction gears 9 and 10, and the drive ring 4 is rotated counterclockwise. At this time, the diaphragm blade 3 is moved by the pin 4a of the drive ring 4, but the pin 3a of the diaphragm blade 3 is guided by the cam groove 2b and gradually moves away from the optical axis. The size of the formed opening gradually increases, and eventually the opening 1a is stopped in a fully opened state. This state is shown in FIG. Therefore, in this state, the subject light guided to the finder by the half mirror is maximum, and the subject image is easy to see.

When the image of the subject is captured and the shutter is released in this manner, two coils 6a are formed before and after the shutter is opened and closed, before and after the half mirror is flipped up.
The current is supplied to and pulse control reverse to the above is performed. Therefore, the rotor 7 rotates counterclockwise, and the drive ring 4 rotates clockwise through the output gear 8 and the reduction gears 9 and 10. Therefore, the three diaphragm blades 3 gradually narrow down the opening area and stop at a predetermined diaphragm opening position. The stop position at this time, that is, the size of the aperture opening may be selected by the photographer in advance, or may be automatically determined by the photometric circuit. After that, the shutter is opened and closed, but when the operation is completed, the half mirror returns to the original position, and the coil 6a is energized to rotate the rotor 7 clockwise to return the diaphragm blade 3 to the state of FIG. A series of operations is completed.

As can be seen from the above description, this configuration eliminates the support plate 35 shown in FIG.
It is possible to reduce the thickness of the drive device as a whole and to reduce the cost, and the reduction in thickness is remarkable particularly in the portion other than the cylindrical portion 5e. Further, according to this configuration, since the iron core member 6 is assembled in the final stage of the assembly work of the entire drive device, the assembly work is easy, and by any chance, the position adjustment and the assembly of the iron core member 6 after the assembly work is completed. It is also extremely advantageous when repair or the like is required. Further, the iron core member 6
First, the legs 6b and 6c are attached to the cylindrical portion 5e.
The holes 6a are inserted into the individual holes 5f formed therein, and then the holes 6a are fitted to the pins 5c and fixed by the hook portions 5d. Alignment becomes easy.

As described above, in the motor used in this embodiment, the rotor 7 has four poles and each iron core member 6 is provided with the two legs 6b and 6c. 4, the rotor 17 has 6 poles, each iron core member 16 is provided with three legs 16b, 16c, 16d, and the coil 16e is wound around each leg 16b. It is also possible to use such a motor, and the number of poles and the number of legs of the rotor are not limited. In FIG. 4, the hole 16a is a hole corresponding to the hole 6a in the above embodiment. In addition, the legs 16b and 16c of each iron core member 16
Although the distance between each end face of and the peripheral surface of the rotor 17 is the same,
The distance between the end surface of the leg portion 16d and the peripheral surface of the rotor 17 is increased by Δd, and the leg portion 16d serves as a commutating pole.

The operation of the motor shown in FIG. 4 will be briefly described. First, in FIG. 4, the relationship between the rotor 17 and the iron core member 16 on the right side will be described.
The state of the figure shows the rest position, and in this state the leg 1
6c directly faces the north pole of the rotor 17, but the leg 16
In b and 16d, the facing positions of the S poles sandwiching the N pole are close to the N pole. Therefore, the coil 16e is energized, the tip of the leg 16b becomes the S pole, and the leg 16c,
When the tip of 16d becomes the north pole, the rotor 1 is provided with the leg 1
Since the repulsive force is exerted by 6b and 16c and the suction force is exerted by the leg portion 16d, the rotor 17 is rotated clockwise.

When the rotor 17 rotates 60 degrees, the coil 1
When 6e is energized in the opposite direction, each leg 16b, 16c, 1
The polarity of 6d is reversed and the rotor 17 is further rotated clockwise by 60
Rotate degrees. By alternately controlling the pulses in this way, the rotor 17 rotates clockwise by 60 degrees and stops at that position unless the coil 16e is energized. Therefore, the rotor 17 is rotated only in the clockwise direction in relation to the right iron core member 16. On the other hand, the iron core member 16 on the left side of the rotor 17 is the iron core member 1 on the right side.
6, the rotor 17 can be rotated by 60 degrees only in the counterclockwise direction by the pulse control for the coil 16e as described above.

Although the above embodiment has been described in the case where the present invention is applied to a driving device for an automatic diaphragm, the present invention is also used as a driving device for opening and closing a shutter and for extending a lens as described above. It can also be applied as a drive device. Further, the driven member (driving ring 4 in the embodiment) is not limited to the one that reciprocates, and includes one that linearly reciprocates and one that rotates in one direction. Particularly, in the case of a lens feeding device, it may be considered to rotate the lens relatively in one direction. When the motor shown in FIG. 4 is applied to the drive device in which the driven member is rotated in one direction, one iron core member is not required, which is advantageous in terms of space and cost. .

[0025]

As described above, according to the present invention, since the reduction gear is supported by the frame member covering the motor rotor and the substrate, the height in the optical axis direction can be reduced as a whole. This is extremely advantageous in terms of space for the camera design. Moreover, the number of parts is reduced, and the cost can be reduced. Further, since the iron core member can be attached to the opposite surface of the frame member supporting the reduction gear after the rotor and the reduction gear are assembled, the assembling work is simplified.

[Brief description of drawings]

FIG. 1 is a plan view of an example showing a minimum aperture opening state.

FIG. 2 is a cross-sectional view showing a main part of FIG. 1 in a partially expanded state.

FIG. 3 is a plan view of the embodiment showing a fully opened state of the diaphragm.

FIG. 4 is an explanatory diagram showing another example of a motor applicable to the embodiment.

FIG. 5 is a partially developed cross-sectional view of a conventional example.

[Explanation of symbols]

 1 Substrate 1a Opening 1b, 5b, 5f, 6a, 16a Hole 1c Engagement 1d, 3a, 4a, 5c Pin 2 Cover plate 2a Groove 2b Cam groove 3 Aperture blade 4 Drive ring 4b Tooth 5 Frame member 5a, 5d Hook part 5e Cylindrical part 6,16 Iron core member 6b, 6c, 16b, 16c, 16d Leg part 6d, 16e Coil 7,17 Rotor 7a Permanent magnet 8 Output gear 9,10 Reduction gear

Claims (3)

[Claims] 1. An iron core having a rotor having a permanent magnet, and a plurality of legs arranged facing each other on a peripheral surface of the rotor at a predetermined interval and having a coil wound around at least one of the legs. A member, an output gear that rotates integrally with the rotor, and one end of its own rotation shaft that meshes with the output gear and is supported by the substrate, and transmits at least one rotation of the rotor to the driven member. A camera comprising: a reduction gear and a frame member attached to the substrate, surrounding at least the rotor between the substrate and supporting the other end of the rotation shaft of the reduction gear. Drive device. 2. The camera drive according to claim 1, wherein the frame member is mounted with the iron core member on a surface opposite to a surface supporting the rotation shaft of the reduction gear. apparatus. 3. The frame member is provided with a restriction portion for arranging the leg portion of the iron core member at a predetermined opposing position with respect to the peripheral surface of the rotor. The drive device for a camera according to 1 or 2.