JPS60216318A - Lens moving device - Google Patents

Abstract

PURPOSE:To move a lens smoothly by providing an operating member which rotates a lens holding frame, control means which has the same center of rotation with the operating member and controls the rotation range of the operating member, and fixing means which fixes the control means to a fixed barrel. CONSTITUTION:The lens holding frame 6 which holds focusing lens groups L1, L2, and L3 is fitted in the internal tube part 5b of the fixed barrel 5, and the cam surface 6a of the lens holding frame 6 is brought into sliding contact with the projection 5a of the fixed barrel 5. When the rotation range is adjusted, parallel light is made incident on a lens through a collimator and the lens holding frame 6 is slid up to a focusing position. Once the focusing position is determined, an adjusting member 16 is rotated at this position so that one of stop plates 17 abuts on a pin 18 provided to an operation knob 13 and the adjusting member 16 is fixed at the abutting position with a screw 20 through a long-sized hole 19 formed in the adjusting member 16. Thus, the adjustment of the rotation range is completed and then the operating knob 13 is rotated to move the lens holding frame 6 in an optical-axis direction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a lens moving device that can be used in video cameras and the like.

Conventional example Is precept and 10 times between them Conventionally, when moving the optical system placed inside the lens IIt body back and forth in the optical axis direction, the hemicoil forms an id thread and performs rotational movement. There are the 115 type and the cam type which forms a cam and performs rotational movement.

Although the cam system has the advantage of being simpler in structure compared to the helicoid system, it also has some drawbacks.

Next, we will explain the cam-type lens movement mechanism in Figures 1 and 2.
This will be explained using diagrams. FIG. 1 is a partial sectional view showing a lens barrel using a cam type lens moving mechanism, and FIG. 2 is an exploded view of the main parts of the lens moving mechanism. The focus lens holding frame 2 holds the focus lens groups +1, 12 and 13, and has an inner cylinder portion 1a formed on the fixed #IL cylinder 1.
is mated to. Roughly speaking, at the tip of the inner cylindrical portion 1a, there are formed protrusions 1b having inclined surfaces at three locations. This projection 1b and a cam surface 3a formed on the focus lens holding frame 2 come into contact, and a spring 4 fixed to the fixed lens barrel 1 presses the cam surface 3b. As a result, the focus lens holding frame 2 is rotatably supported around the optical axis, and is moved in the optical axis direction by being rotated by the inclined surface of the protrusion 1b and the cam 113a.

-2- The following points are the most problematic when moving the lens using the cam type lens moving mechanism configured as described above. That is, when the single-contact focus lens holding frame is manually rotated, a tensile force or moment larger than the pressing force of the spring holding the frame is inevitably generated. This means that the focus lens holding frame may float or the fitting portion may be strained.

OBJECTS OF THE INVENTION An object of the present invention is to prevent harmful forces that cause rattling from acting on the lens holding frame by moving the lens using indirect means, and to ensure accurate and smooth lens movement. The object of the present invention is to provide a lens moving device that enables the lens movement.

Structure of the Invention The lens moving device of the present invention includes a lens holding frame that holds a group of lenses and is fitted into the inner cylinder of a fixed barrel, and that moves in the optical axis direction by rotating around the optical axis opening; an operating member that has a rotation center other than the axis and is attached to the fixed barrel so as to be able to engage with the lens holding frame, and rotates the lens holding frame by its rotation, and an operating member that rotates the same as the operating member; The lens holding frame is provided with a regulating means having a center of motion and regulating a rotation range of the operating member, and a fixing means for fixing the regulating means to a fixed barrel. Prevent harmful forces that cause damage from acting on the
First, accurate and smooth lens movement is possible.

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

FIG. 3 is a configuration diagram of a lens moving device according to an embodiment of the present invention, and FIG. 4 is a sectional view thereof.

The lens holding frame 6 holds the focus lens group L1. L2゜L3
, and is fitted into the inner cylindrical portion 5b of the fixed cylinder 5. In addition, a cam surface 6a (3) is formed on the outer peripheral side of the lens holding frame 6, and this cam surface 6a is in contact with a protrusion 5a formed on the end surface of the fixed barrel 5. 6b is fixed to the fixed barrel 5 and pressed by the crotch spring 7, whereby the focus holding frame 6 is rotatably supported at the optical axis opening. , it comes to move in the optical axis direction via the cam surface 6a. Furthermore, a spur gear 8 is formed on one of the projections 6G on which the cam surface 6a is formed. The idler gear 9 is integrally formed with a crown gear 1G and a spur gear 11, and is rotatably supported by being inserted into a shaft 12 attached to the fixed barrel 5. It engages with a spur gear 8 formed in . The operating knob 13 integrally forms a spur gear 14, is inserted into a shaft 15 press-fitted into the fixed barrel 5, and is rotatably supported, and the spur gear 14 is engaged with the spur gear 11. The adjustment part I416 is rotatably supported by being inserted into the boss part 5C for the press-fit shaft 15 formed in the fixed barrel 5, and has the same rotation center as the operating knob 11. 2 formed in
Rotation of the bottle 18 provided on the operating knob 13 is restricted by a stop plate 17. This allows operation knob 13
The rotation range of the lens holding frame 6 is changed to I&lJ, and the movement range of the lens holding frame 6 in the optical axis direction is restricted.

The operation of the lens moving device formed in the above J shape will be described below. Focus 921 group 11. L2
．． The lens holding frame 6 that holds L3 is attached to the inner cylinder part 5 of the fixed barrel 5.
b, and the cam surface 6a of the lens holding frame 6 is brought into sliding contact with the protrusion 5a of the fixed barrel 5.

When adjusting the rotation range, the lens holding frame 6 is slid into contact with a collimator or the like until the collimated light is incident on the lens and brought into focus. Once the focus position is determined, the adjustment member 16 is rotated so that one piece of the stop plate 17 contacts the bottle 18 provided on the operation knob 13 at this position, and the elongated hole formed in the adjustment member 16 is rotated at this position. The adjustment member 16 is fixed with screws 20 via 19. Adjustment of the rotation range is now complete, and by rotating the operation knob 13, the lens holding frame 6 is moved in the optical axis direction.

In this way, according to this embodiment, by moving the lens using indirect means, harmful forces that cause rattling are prevented from acting on the lens holding frame, and the lens can be moved accurately and smoothly. If it is realized, -6- can be achieved. Furthermore, the lens movement range can be adjusted extremely easily. Although the stop plate is formed on the adjustment member in the embodiment described in -1, the stop plate may be formed on the operating knob and the bottle may be provided on the adjustment member.

Effects of the Invention As is clear from the above description, the present invention is capable of moving in the optical axis direction by holding a lens group, fitting it into the inner cylinder of a fixed barrel, and rotating it around the optical axis. a lens holding frame; an operating member having a rotation center other than the optical axis and attached to a fixed barrel so as to be able to engage with the lens holding frame; and the operating member rotating the lens holding frame by the rotation thereof; A regulation means having the same co-movement center as the operating member and regulating the rotation range of the operating member, and a fixing stage for fixing the regulation means in Section 114 to the fixed cylinder.
Since the C-lens structure is designed to have an opening, it has the excellent effect of preventing the harmful force that would cause rattling from acting on the lens holding frame by moving the C lens using indirect means. This allows for accurate and smooth lens movement. Furthermore, the lens movement range can be adjusted very easily.

[Brief explanation of the drawing]

Fig. 1 is a partial sectional view showing a conventional lens moving device;
3 is a block diagram of a lens moving device according to an embodiment of the present invention, and FIG. 4 is a sectional view of the same. 5... Fixed barrel, 6... Lens holding frame, 7... Spring, 9... Idle gear V110... Crown gear, 11...
・Spur gear, 13...Operation knob, 14...Spur gear,
16... Adjustment member, 17... Stop plate, 18...
・Pin, 19...long hole, 20...screw fee immediate person Mori
Yoshihiro Moto8-

Claims (1)

[Claims] 1. The lens holding frame, which holds the lens group and moves in the direction of the C optical axis by fitting into the fixed inner cylinder and rotating around the optical axis, has one movement center other than the optical axis. an operating member which is attached to the fixed barrel so as to be able to engage with the lens holding frame and rotates the lens holding frame by the rotation of A; A lens moving device comprising a regulating means for regulating a rotation range υ1 and a fixing means for identifying the regulating means to a fixed cylinder.