JPS60237414A - Mount mechanism for zoom lens barrel - Google Patents

Abstract

PURPOSE:To increase mounting strength and to enable easy and accurate fixing of a mount by disposing >=2 pieces each of screws which are engaged with the V-groove provided to a lens barrel and attract the mount to the lens barrel side and set screws with good balance. CONSTITUTION:The V-groove 7 is provided to a master barrel 3 and slotted screws 3 are engageably attached thereto. The slotted screws 5 and pan-head screws 6 for setting are disposed in >=2 pieces each to the barrel 3 with good balance. A spacer 8 is inserted between the barrel 3 and a C mount 4 and the screws 5 are tightened up in the case of adjusting the focal length of a flange to a permissible value. The mount 4 is thereby attracted toward the lens barrel side and is fixed by the screws 6. The mounting strength is thus increased and the easy and accurate fixing of the mount 4 to the lens barrel is made possible with the simple operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a zoom lens barrel suitable for video cameras and the like.

[Background of the invention]

The flange focal length of conventional color and zoom lens barrels inevitably requires adjustment work due to variations in lens balls and in the lens barrel. Therefore, it is necessary to fix it as quickly and easily as possible, taking into consideration accuracy and mounting strength. In addition, plastic lens barrels have recently been rapidly put into practical use in order to reduce manufacturing costs and weight.However, plastic molded products are inferior in strength to conventional aluminum lens barrels, so their practical use is slow. It was also an obstacle.

[Purpose of the invention]

An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a mounting mechanism that is simple, accurate, and strong in mounting strength.

[Summary of the invention]

In order to achieve this object, the present invention provides a mechanism for pulling the Mount If lens into the lens barrel side along the optical axis by providing a groove in the lens barrel and pulling it into this V groove with a screw from the mount side. It is assumed that a tightening screw mechanism for fixing the mount to the lens barrel is provided.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external view showing an embodiment of a zoom lens barrel according to the present invention, and is a partially sectional view. 1 is the focus ring, 2
is the zoom ring, 3 is the master barrel, 4 is the C mount, 4a]
C mount flange surface, 5 is a slotted set screw, and 6 is a flat head screw.In order to adjust the flange focal length to an allowable value, insert an appropriate amount of adjustment spacer between the master tube 3 and C mount 4, and By tightening the index set screw 5,
The C mount 4 is pulled toward the lens barrel along the optical axis and positioned, and the screw 6 is tightened to fix the C mount 4 to the master barrel.

Above, the slotted set screw 5 and the beveled screw 6 each have two pieces at 90°.
They are placed diagonally in a well-balanced manner. Due to this mechanism, the C-mount flange surface 4a can be accurately positioned along the optical axis without wobbling, and sufficient mounting strength can be obtained.

FIG. 2 is an enlarged view showing a specific example of the mechanical part of the slotted set screw 5 shown in FIG. is an adjustment spacer.

By inserting an appropriate amount of spacer 8 and tightening the slotted set screw 5, the C-mount 4 will be pulled toward the master tube 3 along the optical axis by the action of the slope of the groove 7. . Therefore, the flange focal length is adjusted and positioned.

3 is an enlarged view showing a specific example of the mechanical part of the screw 6 for tightening shown in FIG. 1; FIG.

Components corresponding to those in FIG. 2 are given the same reference numerals.

The C-mount 4 is fixed to the master tube 6 by tightening the bevel screw 6 after the flange focal length adjustment position described in FIG. 2 is tightened.

FIG. 4 is a perspective view of a specific example of the master cylinder 3, in which the screw hole 6a1 for tightening the flat head screw 6 and the V groove 7 are integrally molded with plastic on the master cylinder.

FIG. 5 is a perspective view of a specific example of the C-mount 4, with 9
4b1 is a mount flange portion, which has two screw holes for a 5al slotted set screw and two elongated holes for tightening a 6a2 bevel screw in a well-balanced manner on a diagonal of 90 degrees.

FIG. 6 is a perspective view of a specific example of a fixed mount different from the C mount, in which 4a2 is a flange surface, and six flange surfaces are provided in a well-balanced manner in the circumferential direction. Also, as in FIG. 5, the mount flange portion 4bz has a screw hole 5a2 and a long hole 6a3.
are arranged in a well-balanced manner in two 90° diagonals.

Due to such a mounting mechanism, even if the master cylinder 3 is molded from plastic, it is possible to easily obtain sufficient mounting strength.

〔Effect of the invention〕

As explained above, according to the present invention, ・Mount i-
Since the present invention can be easily mounted along the gold optical axis with high precision and strong mounting strength, it is possible to provide an excellent zoom lens barrel suitable for mass production without the drawbacks of the prior art.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view showing an embodiment of a zoom lens barrel according to the present invention, FIGS. 2 and 6 are enlarged sectional views showing a complete example of a mount mechanism section, and FIG. 4 5 is a perspective view showing a specific example of a master cylinder, FIG. 5 is a perspective view showing a specific example of a C mount, and FIG. 6 is a perspective view showing a specific example of a fixed mount. 1... Focus ring 2... Zoom ring 3... Master tube 4... C mount 5... Slotted set screw 6.
...Front screw 7...V groove 8...Spacer 9...C mount screw part 1 Figure 3 Leap 2nd connection 4 View Figure 5

Claims (1)

[Claims] In a zoom lens barrel equipped with a C mount or a fixed mount, when adjusting the flange focal length of the mount, a spacer for dimensional error is inserted between the mount and the lens barrel to adjust the flange focal length within an allowable range. , Maun)
1. In the mechanism for attaching and fixing, for example, the screw and mount 1 are used to pull the mount toward the lens barrel along the optical axis.
=Zoom lens barrel mount mechanism 0 characterized in that at least two or more screws are arranged in a well-balanced manner to be fixed to the lens blunt barrel, and the mount is attached and fixed via the screws.