JPS59172633A - Optical stop device - Google Patents

Abstract

PURPOSE:To provide a small-sized device with a large maximum diameter by fitting pins implanted in a rotary base in grooves formed in diaphragm blades, and forming the grooves so that the respective diaphragm blades are rotated and reduced by the rotation of the rotary base. CONSTITUTION:The annular rotary base 6 is fitted rotatably on a base 1, and three pins 7 are implanted in the rotary base at equal angular intervals. A hook- shaped groove 8 is formed in a diaphragm blade 3, a linear groove 9 is formed in a blade 3, and a pin 7 of the rotary base 6 is fitted in this groove. Therefore, when the rotary base 6 is rotated as shown by an arrow (p), the diaphragm blade 3 is fixed at a position shown by a solid line and the blade 4 stops when notches 5 of three diaphragm blades engage one another to enter a complete closure state. When the stop is fully open, the diaphragm blades 3 and 4 are placed outside of an opening with a diameter D while superposed on each other, so the device is designed while its outer diameter is reduce almost to a little bit larger than (D+D/2).

Description

DETAILED DESCRIPTION OF THE INVENTION An iris diaphragm is generally used as an iris device for optical equipment such as a camera. Jin's diaphragm 2 has multiple wings pivoted at equal angular intervals on an annular base, and when each wing is rotated at the same time, it is surrounded by the wings and forms a shape that is a little wider than necessary. There is a need to.

In other words, when the aperture is fully opened, the outer diameter of the device t'ig is
: o. As described above, conventional iris diaphragms have the disadvantage that it is impossible to make the outer diameter of the device smaller than twice the maximum aperture diameter of the aperture, and the device becomes large compared to the aperture diameter. The present invention eliminates this drawback and provides an aperture device that can increase the maximum aperture with a small device. The drawing is a front view of an embodiment of the present invention, and FIG.
FIG. 2 is a fully closed state, and FIG. 3 is an enlarged view showing only one set of blades in FIG. 2.

In this way, three support shafts 2 are installed at equal angular intervals on an annular base 1, and each support shaft rotatably supports the ends of two aperture blades 3 and 4. It is. The aperture blades 3 and 4 are both crescent-shaped and have the same outer shape except that a notch 5 is provided in the green center portion of the inner side of the blade 4. In addition, an annular rotary table 6 is attached to the inside of the base l so that it can rotate against two bases. Aperture blades 3, 4
The support part (two screws) are each provided with hook-shaped and straight grooves 8.9, into which the bottle 7 is fitted, and the first [ffi In this case, the aperture blades 3 and 4 are completely aligned and the construction is laid on the soil of the base l.
In the figure, it is indicated by a set of lines. In addition, the aperture blades 3 are formed with a J-shaped groove 8 such that the tip side faces the blade's longitudinal direction and the base side is bent at an almost right angle, and the blades 4 and 4 have a straight line facing the longitudinal direction. The drains 9 are formed, and in the state shown in FIG. 1, the bins 7 of the rotary table 6 are fitted at the ends of the blades of these drains. Therefore, when the rotary table 6 is rotated in the direction of the arrow p, the blades 3.4 are first pushed by the bottle 7 and simultaneously start moving toward the center of the annular base l. move in the direction of spindle 2. However, since the vortex 8 is hook-shaped and bent at an almost right angle in the direction of rotation as shown by the arrow p at the center (2), the aperture blades 3 stop moving when the bottle 7 reaches the bend. Stop.

That is, in this state C2, the bent portion of the groove 8 is formed so that it exactly matches the ih :;= of the bottle 7 (-), so that when the turntable 6 is further rotated in the direction of the arrow p, The aperture blades 3 are located at the position 1 (
The blades 4 having the straight grooves 9 are further moved to the center of the base (-), and the notches 5 of the three aperture blades 4 are aligned as shown in Fig. 2. When the aperture stops, the aperture stops and the aperture is fully adjusted.The solid line in Fig. 3 is an enlarged view of one set of aperture blades 3.4 at this time. When the aperture is rotated in this direction, the diaphragm expands in the reverse order as described above and returns to the fully open state as shown in FIG.

In this way (2), in the device of the above-mentioned example, the two aperture blades 3 and 4 overlap as shown in Fig. 1 in the state of full IJ, and the aperture 1
0, and when the aperture IQ is completely closed, the aperture blades 3 close the aperture l as shown in FIGS. 2 and 3.
The periphery of O is covered, and the center part is covered by the aperture blades 4. Therefore, the maximum aperture diameter of the diaphragm device should be
1 width is W and 4, W is larger than the noise (= can be selected) When the aperture is fully open, this aperture blade 3
, 4 are superimposed and placed outside the diameter opening as shown in Figure 1!
Therefore, the outer diameter of the device can be designed to be somewhat larger than w<D+Jrr7>. In other words, the conventional iris diaphragm could not reduce the outer diameter to less than 2D as mentioned above, but the iris device of the embodiment can reduce the diameter to the full size (D 1 D/2) (approximately 2D). It can be made smaller.Also, the aperture blades are supported by a single shaft!
It is clear that the outer diameter of the device becomes smaller by increasing the number by 1.

[Brief explanation of the drawing]

The drawings show Embodiment 7 of the present invention; FIG. 1 is a front view of the aperture in its fully open state, FIG. 2 is a front view of the aperture in its fully closed state C2, and FIG. It is an enlarged view with the aperture blades removed. In the figure, l is the base, 2 is the support shaft, 3.4 is the aperture blade,
5 is notch, 6 is turntable, 7 is bottle, a, 9 is disease, lO
is the aperture of the diaphragm. Patent Translator Former Headquarters Secret Instruments Co., Ltd. Agent Patent Attorney Tatsuya Masuda

Claims (1)

[Claims] An annular base (a plurality of spindles planted at equal angular intervals rotatably support the aperture blades for converging sheets, respectively), and is coaxial with the current base (equally angular to the two-part rotating base). The same number of pins as the above-mentioned support shafts, which are planted at intervals, are formed on each of the plurality of aperture blades supported by the same support shaft.
(=The two aperture blades are fitted together, and each aperture blade is superimposed on the base by the rotation of the rotary table, and rotates in a direction to reduce the aperture hole, so that the aperture blades are rotated in the direction of reducing the aperture hole. An optical diaphragm device characterized in that the FJ of each diaphragm blade is formed in a different shape (2) so that each diaphragm blade sequentially stops at a different position.