JPS646487Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a lens barrel device that can be used in optical equipment such as video cameras.

Conventional configurations and their problems In recent years, the uses of optical-related equipment have rapidly expanded with the advancement of electronics, and along with this, the demand for improved productivity has also increased. Attempts are being made to improve productivity and reduce costs by using resin for so-called lens barrels that support optical elements.

However, resins often behave differently from metals, and conventional structures cause various problems.

The example shown in Fig. 1 is one such example, and the structure in which a lens barrel 2 holding several lens groups (1 is one of them) is fixed to another lens barrel 3 is a so-called master lens group. Often used as a fixing method. To explain in more detail, the lens barrel 3 is supported on the device main body via the mounting hole 5 provided in the flange portion 4 of the lens barrel 3, the lens barrel 2 is fitted on the excitation side of the lens barrel 3, and the lens barrel Roughly position the shaft 8 so that the groove 6 provided in the barrel 2 fits into the hole 7 provided in the lens barrel 3.
By rotating the eccentric pin 10 with the shaft 9 engaged with the hole 7 and the shaft 8 engaged with the groove 6, the lens barrel 2 is aligned with the light of the lens. The back focus is adjusted by moving it in the axial direction, and after the adjustment is completed, the screw 12 is screwed into the screw hole 11 provided in the lens barrel 3, and the tip of the screw 12 is pressed against the lens barrel 2 to fix it. After that, remove the eccentric pin.

The focus position of the lens system is adjusted by the above operation. With lens barrels made of metal members, there were no problems when used with the above configuration, but when the lens barrel 2 was made of resin, the position of the lens barrel 2 moved during use, resulting in poor focus. It turns out that a serious problem arises. The amount of movement mentioned above is a problem in terms of optical accuracy, and it is thought that the amount of movement that is difficult to notice in other mechanical parts occurs.

Purpose of the invention The object of the invention is to provide a lens barrel device that can accurately fix a lens barrel made of resin over a long period of time.

Structure of the Invention The lens barrel device of the present invention includes a lens barrel body into which a resin barrel holding a lens can be slidably fitted in the optical axis direction, and the lens barrel body is substantially perpendicular to the optical axis. The elastic piece has a screw hole having an axis in the direction of displacement, and the lens barrel body has a hole that allows a screw to be screwed into the screw hole to enter. and is configured to fix the resin lens barrel to the lens barrel main body with the tip of the screw in pressure contact with the resin lens barrel, and thereby,
This allows the resin lens barrel to be fixed with high precision for a long period of time.

DESCRIPTION OF EMBODIMENTS The present invention will be described below based on illustrated embodiments.

FIG. 2 is an exploded view for explaining one embodiment of the present invention. In the figure, a resin barrel 14 holding a lens 13 is fitted onto an inner surface 16 of a barrel body 15 and is slidable in the optical axis direction of the lens 13. is established,
The flange 17 is provided with a mounting hole 18 and an elastic piece 19. The elastic piece 19 can be elastically displaced in a direction perpendicular to the optical axis direction of the lens 13, and a screw hole 20 having an axis in the direction of elastic displacement is provided at the tip of the elastic piece 19. . A hole 21 having the same axis as the screw hole 20 and larger than the outer diameter of a screw 22 to be screwed into the screw hole is provided on the side surface of the lens barrel body 15. A hole 23 provided on the side surface of the lens barrel body 15 is also engaged with a groove 25 provided in the resin lens barrel 14 by an eccentric pin 24, as in the conventional example, to adjust the back focus of the lens system. .

FIG. 3 shows the assembled state of the resin lens barrel 14, lens barrel main body 15, and screw 22 shown in FIG. 2 in a cross section perpendicular to the optical axis. A screw 22 that comes into contact with the outer surface of the resin barrel 14 fitted into the barrel body 15
When turned further in the direction of pushing in, the elastic piece 19 is displaced upward in the figure, and the restoring force of the elastic piece 19 causes the tip of the screw 22 to continue applying pressure to the resin lens barrel.

With the above configuration, even if the resin lens barrel 14 is deformed to escape from the pressure of the screw 22 due to creep or temperature change, the tip of the screw 22 will remain in the resin lens barrel 14 as long as the amount of displacement of the elastic piece 19 allows. It is possible to continue to be in pressure contact with the resin lens barrel, and to continue to prevent movement of the resin lens barrel in the optical axis direction.

FIG. 4 shows only the lens barrel body in another embodiment of the present invention. This is a cylindrical part 2 having an inner diameter sufficient to fit a resin lens barrel inside.
A notch 29 is provided in a part of the cylindrical portion 26 of the lens barrel main body 28, which is made up of a flange portion 26 and a flange portion 27, and a hole 30 communicating with the space inside the cylinder is bored.
Furthermore, an L-shaped elastic piece 31 is provided on the cylindrical portion 26 so as to cover the notch 29, and a screw hole 32 is provided at the tip of the elastic piece 31. 3
3 is a mounting hole, and 34 is an engagement hole for an eccentric pin.

The above configuration has the advantage that even if the elastic piece 29 is displaced, the flatness of the flange portion 27 does not change, and the mounting angle of the lens barrel body 28 does not change.

In the present invention, the material of the lens barrel having the elastic piece can be either metal or resin.

Effects of the invention As is clear from the above explanation, the lens barrel device of the present invention can be made of resin without deteriorating optical performance, leading to improved productivity and cost reduction. It is something that can be done.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a conventional lens barrel device, FIG. 2 is an exploded perspective view of an embodiment of the lens barrel device of the present invention, and FIG. 3 is a sectional view of the structure shown in FIG. 2 in an assembled state.
FIG. 4 is a perspective view of main parts of another embodiment of the present invention. 13...Lens, 14...Resin lens barrel, 15...
... Lens barrel body, 19, 31 ... Elastic piece, 20, 32
...screw hole, 22...screw.

Claims (1)

[Scope of utility model registration request] The lens barrel body is provided with a lens barrel body into which a resin lens barrel holding a lens can be slidably fitted in the optical axis direction, and the lens barrel body has an elastic material that can be elastically displaced in a direction substantially perpendicular to the optical axis. The elastic piece has a screw hole having an axis in the direction of displacement, a hole is provided in the lens barrel body through which a screw to be screwed into the screw hole enters, and a screw is provided in the resin lens barrel. A lens barrel device configured to fix the resin lens barrel to the lens barrel main body with a tip of the resin barrel being pressed into contact with the lens barrel.