JP2577666Y2 - Camera aperture device - Google Patents

Description

[Detailed description of the invention]

[0001]

This invention relates to a technique in which a plurality of opening / closing members having an aperture opening forming portion for restricting the amount of light incident on a light receiving portion of a video camera or the like, for example, aperture blades, are directed in a direction intersecting light incident on the light receiving portion. The present invention relates to a diaphragm apparatus for a camera, which moves the light beam to the aperture opening forming section to change the size of the opening and adjusts the amount of light incident on the light receiving section.

[0002]

2. Description of the Related Art Conventionally, in a diaphragm apparatus of a video camera, a plurality of diaphragm blades are driven by a driving device K shown in FIGS.

FIG. 6 is an exploded perspective view of a main part of the driving device K, and FIG. 7 shows a state where the main part is to be inserted into a hollow cylindrical yoke 7 after the main part is assembled.

This device K has a permanent magnet body 1 formed integrally with a drive shaft 2, and a pair of bobbins 4a, 4b having pockets h, h for accommodating the permanent magnet body 1 therein.
Washers 3 for supporting both ends of the drive shaft 2
a and 3b are added.

[0005] Each of the bobbins 4a, 4b has a coil body e1, e for winding a coil for guiding a signal current from a video camera.
2, but the coil itself is not shown.

[0006] At least one of the bobbins 4a and 4b has an accommodating portion c for the magnetic sensor 8 as shown in the figure. The terminal pins 5a, 5b, 6a, and 6b for fixing the ends of the coils in the direction parallel to FIG.

Then, the permanent magnet body 1 is housed inside, the bobbins 4a and 4b are united, the terminal pins 5a, 5b, 6a and 6b arranged at substantially square positions are inserted, and the magnetic sensor 8 is carried. The printed board 9 thus assembled is assembled as shown in FIG. 7, and is inserted into the hollow cylindrical yoke 7.

[0008]

However, in the conventional driving device K as described above, the terminal pins 5a and 5b are
a, and the terminal pins 6a, 6b are attached to the bobbin 4b. Moreover, as shown in the drawing, the terminal pins are provided at positions apart from the surface and close to the yoke 7, so that each terminal pin must be arranged at a close interval to each other. Therefore, as shown in FIG. The width L2 of the constriction of the printed board 9 must be smaller than the width L1 of the sensor carrier, and after the main parts are assembled in the yoke 7, the printed board 9 is assembled, and the sensor carrier is pivoted inside. Even if you try to insert from outside the direction, you cannot pass through the constricted part. For this reason, as shown in FIG. 7, the printed board 9 must be passed through each terminal pin, and the supporting portion of the magnetic sensor 8 must be bent and folded into the yoke 7 as shown in the figure. .

In addition, if the drive shaft 2 is divided into two parts at the center of the axis as shown in FIG. 6, it takes a relatively long time to assemble the apparatus, making it impossible to carry out appropriate automation. , D2 are unlikely to be completely cylindrical, and therefore require parts such as bearing washers 3a and 3b as shown in the figure.

An object of the present invention is to provide a diaphragm device for a camera in which a printed board can be mounted and a magnetic sensor can be mounted even after a yoke is mounted on a bobbin, and an assembling operation can be performed from one direction.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a diaphragm apparatus for a camera, comprising: a diaphragm section for adjusting the amount of light incident on a light receiving section; and a drive section for driving the diaphragm section. The drive unit includes a permanent magnet body having a drive shaft for transmitting a driving force to the throttle unit, and a rotatable housing of the permanent magnet body with the drive shaft as a rotation axis, and is divided in an axial direction of the drive shaft. A first bobbin coupled to the throttle unit, a second bobbin coupled to the first bobbin, and a peripheral surface of the bobbin in a state where the permanent magnet body is rotatably accommodated in the bobbin. A coil wound along the axis, a plurality of terminal pins provided at an end of the second bobbin on a side opposite to the first bobbin side, to which the coil is coupled; The bobbin set in the axial direction A yoke inserted to cover the periphery of the bobbin, a magnetic sensor inserted between the bobbin and the yoke to detect a rotational position of the magnet body, and the magnetic sensor is attached, and the yoke is provided around the bobbin. And a conductor printed board mounted on the plurality of terminal pins from the axial direction in the mounted state.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

<Structure> FIGS. 1 and 2 are exploded perspective views of a camera in which the aperture device of the embodiment of the present invention is applied to an aperture device of a video camera.

As shown in FIG.
And a diaphragm unit 50 that is opened and closed by the blade drive unit 10.

As shown in FIG. 2, the diaphragm unit 50 is
A base plate 51 for attaching the first opening and closing member for example diaphragm blades E _1, a second closing member for example diaphragm blades E _2, almost the same shape as the diaphragm blades E _1, first provided to sandwich the diaphragm blades E ₂ a closing member for example diaphragm blades _{E 3} of 3, covers the one surface of the base plate 51, the blade _{E 1, E} 2 squeezed between the base plate 51,
A pressing plate 70 for sandwiching the E ₃ slidably, aperture blades E
_An operating lever 90 that engages with E ₁ , E ₂ , and E ₃ and transmits the driving force of the blade drive unit 10, and an urging spring 95 that constantly biases the operating lever 90 in one direction.

As shown in FIG. 1, an optical path opening 52
And a mounting portion 53 of the blade drive unit 10 and several engagement protrusions 55a, 55b,
56a, 56b, fitting ribs 57a, 57b, small holes 54 for driving shaft penetration, and locking projections 58a, 58b for holding the lead wire printed board 38 are provided.

A relief 52N is formed in the optical path opening 52 so as not to hinder the movement of an ND filter 89 described later.

Further, diaphragm blades E ₁ , E ₂ , E
₃ As can move without sliding contact with each other, these diaphragm blades _{E 1,} E 2, _{E 3} sliding engagement with engagement pins 59a,
59b and, like projection 61a~61h for floating the wings _{E 1,} E 2, _{E 3} aperture is provided.

[0019] actuating lever 90 and the hole 91 for fitting the driving shaft of the blade drive unit 10, the diaphragm blades _{E 1,} E 2, _{E 3} and the engaging pin portion 92a, and a 92b is provided.

The aperture blades E ₁ and E ₃ are formed, for example, of thin pieces of black polyester and have the same shape, for example, and include an aperture opening forming portion 80 for regulating the amount of light and a pin portion 92b.
And a small hole 82 that engages with the engaging pin 59b.

Meanwhile, the diaphragm also blades E ₂ is formed like flake black polyester, the aperture forming portion 85 for regulating the amount of light, the pin portion 92a and the mating ostium 87, the engaging pin 59a and engages A matching long hole 88 is provided.

[0022] Note that the deepest portion of the opening 80 of the diaphragm blade _{E 1,} the light amount adjusting member e.g. ND filter (Neutra
l Density Filter) 89 is stuck.

The holding plate 70 has an optical path opening 71, elongated holes 72 a and 72 b formed so that the pin portions 92 a and 92 b of the operating lever 90 can rotate, and coupling portions 74 a and 74 b for coupling to the main plate 51. engaging pins 59a, 59b faces the hole 75a, and 75b, and projections 62a~62d for floating the wings _{E 1,} E 2, _{E 3} aperture is provided.

[0024] Note that the aperture blades _{E 3} in the optical path aperture 71 N
An escape portion 71N is formed so as not to hinder the movement of the ND filter 89 when affixed to the D filter 89.

Next, the configuration of the blade drive unit 10 will be described.

As shown in FIG. 1, the blade drive unit 10 includes a permanent magnet 11 pivotally supported at the center thereof and a coupling bobbin 14 divided in the axial direction surrounding the permanent magnet 11.
(The first bobbin) and the pin-side bobbin 25 (the second bobbin), and the drive coil 130A and the brake coil 130 wound around the bobbins 14 and 25 along the axis as shown in FIG.
B and a hollow-cylindrical magnetic circuit member (yoke) that fits on the outer periphery of both bobbins 14 and 25 and guides the magnetism of permanent magnet body 11.
35 and an end plate 36 for holding the end of the magnetic circuit member 35
And a magnetic sensor 37 for detecting the rotational angle position of the permanent magnet body 11.
A, 130B, and a conductive wire printed board 38 connected thereto.

The permanent magnet body 11 is a cylindrical magnet 12
And a drive shaft 13 fixed through the center of the cylinder of the magnet 12, and the bobbin 14 and the bobbin 25
And is rotatably supported inside.

On the upper part of the bobbin 25, the coils 130A, 1
Terminal pins 29a, 29b, 29 for winding the wire ends of 30B
c, 29d are provided.

Then, as shown in FIG. 3, the magnetic circuit member 35 is fitted and covered with the end plate 36. Thereafter, the magnetic sensor 37 is inserted between the bobbins 14, 25 and the magnetic circuit member 35, and the printed wiring board 38 is inserted. The four small holes formed in the terminal pins 29a, 29b, 29c, 29d
And put it through.

Finally, the terminal pins 29a, 29b, 29c,
The assembly of the blade drive unit 10 is completed by joining the 29d and the printed wiring board 38 with solder or the like. Even after the magnetic circuit member 35 has been incorporated into the bobbins 14 and 25, the printed wiring board 38 is attached and the magnetic sensor 37 is mounted.
Can be assembled, and the assembly operation can be performed from one direction.

The description of the assembly on the throttle unit 50 side is omitted.

Here, the mutual relationship between the respective aperture blades E ₁ , E ₂ and E ₃ will be described. First, the conventional aperture blade will be briefly described.

The throttle device of a conventional camera, without the blade E _1, E ₂ mutual frictional resistance diaphragm as shown in Figure 5, in order to reduce the power requirement of the drive means, to move across a small gap g It is configured.

Now, the distance between the ends a and b of the aperture opening forming portions of the aperture blades E ₁ and E ₂ is bisected (the distance J between the center line and the ends a and b), and is perpendicular to the light receiving surface R. foot O on the light-receiving surface of the line O ₁
From each other, take equal distances L and L, and represent representative points A and B, respectively.
Then, the incident angle α + 微小 α differs from the incident angle β + △ β due to the existence of the minute gap g as described above, and the incident light a _{1 to} a ₂ incident on the point A and the incident light incident on the point B Light b ₁
Obviously different amount from ~b _3, the former is less than the latter.

If AB is located at both ends of the light receiving element, in such an arrangement, the distribution of the amount of light incident on the light receiving element is not uniform, and the output of the light receiving element, for example, the CCD becomes unbalanced. Deteriorate the quality of the formed image.

Therefore, this embodiment is configured as shown in FIG. 4 in order to reduce the variation in the amount of light incident on the light receiving unit depending on the position of the light receiving unit.

FIG. 4 is a two-dimensional figure cut on a virtual plane perpendicular to the light receiving surface R in the moving direction of each of the diaphragm blades E ₁ , E ₂ , E ₃ .

The ends of the aperture openings 80, 85 and 80 of the aperture blades E ₁ , E ₂ and E ₃ are denoted by a, b and c, respectively. Further, as shown in the figure, each of the adjacent diaphragm blades E ₁ , E
_2, a small gap between _{E 3} respectively and g. That, is arranged at the position of the blade E ₁ stop relative to the blades E ₂ aperture diaphragm blades E ₃ symmetry.

Further, the space between the end a and the end b is bisected,
And the point of intersection with the light receiving surface R of the line O ₁ perpendicular to the light receiving surface R and O, sets the representative points A, B equal distance L to the left and right from the point O, at the L. Then, the incident light entering the point A and _a 1 ~a _2, the incident light to the point B and _b 1 ~b _2.

[0040] Thus, in order to makes it substantially uniform light amount distribution of the light incident inclined light receiving surface R, the diaphragm blade E ₃ of the diaphragm blades E ₁ and the same shape, on the basis of the aperture blade E ₂ together arranged at the position of the diaphragm blades E ₁ and symmetrical, since to move the diaphragm blades E _{1 adjacent,} E _2, E ₃ to each other to each other to relatively opposite directions, the diaphragm of the diaphragm blades E _1, E ₂ the diaphragm blade E ₁ side of the diaphragm opening formed by the opening forming portions 80 and 85, will be shielded by the aperture stop forming portion 80 of the diaphragm blade E ₃ which moves in the same direction as the diaphragm blades E _1, the light receiving portion Variations in the amount of incident light at the light receiving position can be reduced. For this reason, the output of the light receiving element of the camera which receives such incident light is uniform and uniform, and a high-quality image can be formed.

<Modifications> One embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and for example, the following modifications are possible.

[0042] (1) was a blade E ₃ and aperture diaphragm blades E ₁ is the same shape in the embodiments, may not be the same shape.

[0043] (2) In the aforementioned exemplary but has a blade E ₃ squeezing blades E ₂ to the position of the diaphragm blades E ₁ and symmetrically to the reference aperture is provided in the example, has an end portion d of the opening forming portions stop as shown in FIG. 4 distance between blades E ₂ aperture diaphragm blades E ₄ may be provided at a position of g is larger than g _1. The distance between the blades E ₂ aperture diaphragm blades E ₅ having an end portion e of the aperture forming portion may be formed at a position of g is less than g _2.

[0044] (3) wherein at was located farther from the stop blade _E 1 squeezing blade _{E 3, E 2} receiving surface R in the examples, aperture of the stop blade _E 1, _{E 2} at a position closer to the light receiving surface R it may be arranged wings E _6. That may be disposed vanes E ₆ diaphragm between the diaphragm blades E ₁ receiving surface R. In this case, the first, second and third opening / closing members are each provided with an aperture blade E
₆ , E ₁ and E ₂ .

(4) Since the first and third opening / closing members move in the same direction, either one of the first and third opening / closing members is attached to the other opening / closing member, and both are integrated. You may make it move temporarily.

(5) In the above-described embodiment, the half-moon-shaped aperture opening forming portions 80 and 85 are shown. However, the aperture opening forming portion may be, for example, a circular hole.

(6) The aperture forming portions of the first, second, and third opening / closing members may have similar shapes.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an overall structure of a diaphragm device of a camera according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the throttle unit of FIG.

FIG. 3 is an exploded perspective view showing a structure of a blade driving unit in FIG. 1;

FIG. 4 is an explanatory diagram showing a distribution of incident light passing through a stop aperture of a camera formed by an opening of an opening / closing member in one embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a distribution of incident light passing through an aperture of a camera formed by an opening of an opening / closing member of a conventional aperture device.

FIG. 6 is an exploded perspective view of a main part of a driving unit of a conventional diaphragm device.

FIG. 7 is a perspective view showing a procedure for assembling a drive unit of a conventional aperture device.

[Explanation of symbols]

E Aperture device for camera 10 Blade drive unit E ₁ Aperture blade (first opening / closing member) E ₂ Aperture blade (second opening / closing member) E ₃ Aperture blade (third opening / closing member) 80 Aperture opening forming unit 85 Aperture opening Forming part g Minute gap between open / close members g ₁ Minute gap between open / close members g ₂ Minute gap between open / close members

Claims (1)

(57) [Scope of request for utility model registration] 1. A diaphragm device for a camera, comprising: a diaphragm unit for adjusting the amount of light incident on a light receiving unit; and a driving unit for driving the diaphragm unit, wherein the driving unit transmits a driving force to the diaphragm unit. A first bobbin that accommodates the permanent magnet body rotatably around the drive shaft and that is coupled to the throttle section divided in the axial direction of the drive shaft; A second bobbin coupled to the first bobbin, a coil wound along the axis on a peripheral surface of the bobbin in a state where the permanent magnet body is rotatably housed in the bobbin, A plurality of terminal pins provided at an end of the bobbin opposite to the first bobbin side, to which the coil is coupled, and a plurality of terminal pins which are inserted into the bobbin around which the coil is wound from the axial direction and surround the bobbin. A yoke for covering the And a magnetic sensor inserted between the yoke and detecting the rotational position of the magnet body, the magnetic sensor is attached, and the yoke is mounted around the bobbin, the plurality of the plurality of magnetic sensors from the axial direction. A diaphragm device for a camera, comprising: a printed circuit board mounted on terminal pins.