JPH0588232A - Structure for attaching diaphragm device - Google Patents

Abstract

PURPOSE:To attach an iris meter to a lens barrel without looseness by a fitting system without using a fastening member such as an attaching screw. CONSTITUTION:As to a blade case 3 which is attached to the front end of a 1st lens barrel 1 by the fitting system, its radial receiving part 3b is abutted on the notched part 1d of the lens barrel 1 to regulate the position in a radial direction. Furthermore, the looseness in the radial direction of the case 3 is prevented by spring force generated by allowing a charge arm 10 formed integrally with the case 3 to abut on the charging groove 1b of the lens barrel 1. In such a case, by making one side surface of the groove 1b an inclined surface, the component force of the arm 10 also acts on an optical axis direction and simultaneously the looseness in the optical axis direction is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a diaphragm device called an iris meter, which is used in a video camera or the like.

[0002]

2. Description of the Related Art A conventional iris meter is attached to a lens barrel by, for example, the structure shown in FIGS. Reference numeral 1 is a first lens barrel, 2 is a second lens barrel, a second lens barrel 2 is arranged in front of the first lens barrel 1, and an iris meter is arranged between them.

A blade case 3 of a diaphragm device is provided at the front end of the first lens barrel 1, and a base plate 4 serving as an exterior of the iris meter is fixed to the blade case 3 by a base plate holding portion 3d. The blade case 3 is formed with a radial receiving portion 3b that engages with the first lens barrel 1 in the radial direction and regulates the position in the radial direction, and is in contact with the rear end of the second lens barrel 2 in the thrust direction. Thrust receiving part 3c where the position of the
Are formed. Reference numeral 3e is a radial receiving portion relief groove that serves as a relief when the radial receiving portion 3b receives a lateral pressure in the radial direction, and 6 is an iris driving portion.

At the front portion of the first lens barrel 1, screw holes 1a and a fitting boss 1c are formed diagonally, respectively.
In the state where the fitting boss 1c is accommodated in the second lens barrel 2
The second lens barrel 2 is attached to the front portion of the first lens barrel 1 so as to be fitted in the fitting holes (not shown) of the first lens barrel 1 and the two lens barrels are connected by the connecting screw 5 which is passed through the screw hole 1a. 1, 2 are integrally connected.

That is, the iris meter regulates the radial movement of the first lens barrel 1, the outer shape of the blade case 3 and the radial receiving portion 3b of the blade case 3, while the first lens barrel 1 is used. The position of the iris meter in the thrust direction is regulated by fixing the thrust direction by the gap formed by the second lens barrel 2, the outer shape of the blade case 3, and the thrust receiving portion 3c of the blade case 3.

[0006]

However, the conventional iris meter mounting structure has the following problems.

When the iris meter is fixed, when the dimensional accuracy of the components of the first and second lens barrels 1 and 2 and the blade case 3 is poor, the iris meter is apt to rattle, and the iris meter with respect to the optical axis of the lens system is The center becomes unstable, which adversely affects the optical performance.

Further, when the lens driving motor or the like is operating, there is a possibility that an abnormal noise may be generated due to the backlash of the iris meter.

The present invention solves the above problems,
It is an object of the present invention to provide a diaphragm device mounting structure capable of improving performance without increasing the number of parts.

[0010]

SUMMARY OF THE INVENTION A diaphragm device mounting structure for achieving the object of the present invention is a diaphragm device mounting structure for mounting and positioning a diaphragm device body in a lens barrel in a fitting manner. Spring means for urging the lens barrel in a direction at least orthogonal to the optical axis direction of the lens barrel is provided in the diaphragm device main body or the lens barrel.

[0011]

In the mounting structure of the diaphragm device having the above-described structure, the spring means is provided integrally with, for example, the body of the diaphragm device, and this spring force presses the body of the diaphragm device against the lens barrel, thereby loosening the diaphragm device. Instead, it is fitted and held in the lens barrel.

[0012]

1 and 2 are views showing a first embodiment of a mounting structure of a diaphragm device according to the present invention. In this embodiment, the same members as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, the charge arms 10 having spring properties are integrally formed on both sides of the upper portion of the blade case 3, and the tips of these charge arms 10 are formed on both shoulders of the first lens barrel 1. Is engaged with the charging groove 1b.

That is, the radial receiving portions 3b, which are provided on the right and left sides of the blade case 3 respectively, are engaged with the cutout portions 1d of the first lens barrel 1, so that the blade case 3 is charged with these charges. Since the radial receiving portion 3b is pressed against the cutout portion 1d by the spring force of the arm 10, rattling in the radial direction is prevented.

On the other hand, in this embodiment, the rear surface of the charge groove 1b formed in both shoulders of the first lens barrel 1 is directed forward (to the second lens barrel side) as shown in FIG. Since the inclined surface is inclined, the component force of the charge arm 10 generated by contacting the inclined surface acts on the front side, so that the blade case 3 is prevented from rattling in the thrust direction.

In the embodiment described above, the charge arm is provided on the blade case 3 and the tip of the charge arm is engaged with the charge groove formed on the first lens barrel 1, but as shown in FIGS. Even if the charge arms 20 having spring properties are provided on both shoulders of the first lens barrel 1 and the upper ends thereof are engaged with the charge grooves 21 provided on the blade case 3, the same effect can be obtained. can get.

[0017]

As described above, according to the present invention, vibration occurs when the lens driving motor or the like is operating, but the diaphragm device including the blade case is pressed by the spring force. Therefore, it is possible to prevent the generation of abnormal noise due to rattling.

Further, since it is not necessary to screw the blade case or the like to the lens barrel, the screw or the like is unnecessary, the number of parts can be reduced, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a diaphragm device mounting structure according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a sectional view showing a mounting structure of a conventional diaphragm device.

FIG. 4 is a side view of FIG.

FIG. 5 is a sectional view of the second embodiment.

FIG. 6 is a side view of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st lens barrel 2 ... 2nd lens barrel 3 ... Blade case 4 ... Base plate 5 ... Connection screw 6 ... Iris drive part 10, 20 ... Charge arm 1b, 21 ... Charge groove

Claims (2)

[Claims] 1. A structure for mounting a diaphragm device in which a diaphragm device main body is fitted and positioned in a lens barrel in a fitting manner,
Attachment structure for a diaphragm device, characterized in that spring means for urging the diaphragm device body in a direction at least orthogonal to the optical axis direction of the lens barrel is provided in the diaphragm device body or the lens barrel. . 2. The groove according to claim 1, wherein the aperture device main body or the lens barrel is provided with a groove portion against which the spring means abuts, and the groove portion is formed with an inclined surface on which the component force of the spring force of the spring means acts in the optical axis direction. A structure for mounting a diaphragm device, which is characterized in that