JPS59192213A - Lens moving device - Google Patents

Abstract

PURPOSE:To reduce the number of parts by interlocking a correcting lens moving frame through a cam plate, which is rotated in a plane parallel with the optical axis, to perform the zooming operation. CONSTITUTION:A cam plate 23 where grooves 25 are formed radially from the center of turning for the purpose of moving a power varying lens moving frame 27 in the direction of the optical axis and a cam groove 26 is formed for the purpose of moving a correcting lens moving frame 28 in the direction of the optical axis is provided and is set freely turnably for a shaft 40 provied on a lens substrate 22. A projecting part 49 formed in an operating member 48 is engeged with a notched groove 27c formed in the variable power lens moving frame 27. The operating member 48 is provided with an operation knob 47, and it is projected to the outside from a long hole 51 formed in a casing 50 indicated by an alternate long and short dash line and is movable in the direction of the optical axis.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a lens moving device for a video camera or the like.

The lens barrel is equipped with a mechanism that moves the lens in the direction of its original axis in order to perform focus operations, zoom operations, focus adjustments, etc. In particular, during zoom operations, the holding frame of the zoom lens is moved by several indirect members. Currently, it is used to move the vehicle.

A typical conventional zooming mechanism that moves a lens using a cam barrel attached to a fixed barrel will be described below with reference to FIG.

FIG. 1 shows a cross section of the main parts of a conventional zoom lens barrel, in which 1 is a fixed barrel, 2 is a focusing lens group L1.
L2. This is a focus ring that holds L3. A helicoid screw 2a provided on the focus ring 2 is screwed into a helicoid screw 2a provided on the fixed barrel 1, and when the focus ring 2 rotates around the optical axis, the focusing lens groups Ll, L2. L3 moves in the optical axis direction.

Variable power lens group L4. L5. L6 is fixed and attached to the variable power lens moving frame 8 by screwing the screw portion 9a of the L4 lens holder 9 into the screw portion 8aK of the variable power lens moving frame 8. Slope portion 10a provided along the inner periphery of the correction lens group
fixed to the correction lens moving frame 10 by fitting into the
It is installed.

6a, 6b, and 6c kiteballs, and can be fully supported by inserting one end into the hole 1b formed in the fixed tube 1 and the other end into the hole 7a formed in the ball support plate [near Vc]. . The kite ball 6a is inserted into a hole 8c provided in the variable magnification lens moving frame 8, and the guide ball 6b
is inserted into the hole 10c provided in the correction lens movement frame 10, and the guide ball 6c is inserted into the notch 8b of the variable power lens movement frame 8 and the notch 10 of the correction lens movement frame 10.
1] is engaged with. The ball support plate 17Kld has a protruding protrusion (not shown) formed on its outer periphery, and when this engages with a notch (not shown) formed in the fixed cylinder 1, a KJ: guide is formed. Ball 6a+ 6b+
The holes 17a supporting the holes 6c are aligned in phase. The ball support plate 17 is fixed by a presser ring j6. 5 is a cam cylinder provided with a first cam groove 14 and a second cam groove 15 for moving the variable magnification lens moving frame 8 and the correction lens moving frame 0 in the optical axis direction. The first cam groove 14 includes variable power lens group L4. L5. A first lens mounted on the variable magnification lens moving frame 8 in order to regulate the position of L6 in the optical axis direction.
cam follower 12 is engaged. Similar 1c, @2
A second cam follower 13 embedded in the correction lens moving frame 10 is engaged with the cam groove 15 in order to regulate the position of the correction lens group L7 in the optical axis direction. 18 is a zoom ring, into which a zoom gear 21 is fitted so as to be rotatable around the optical axis. Furthermore, the long groove 1 formed on the inner cylinder side]
A pin 2° implanted in the cam cylinder 5 is engaged with the pin 9.

When the zoom ring 18 is rotated around the optical axis, the long groove ] 9
The pin 20 engaged with is driven, and the cam cylinder 5 rotates around the optical axis. The first cam follower 14 engaged with the first cam groove 14 and the second cam follower 13 engaged with the second cam groove 15 are connected to each cam groove 14. ], 5 and move in the optical axis direction. In this way, zooming is performed by moving the variable power lens moving frame 8 and the correction lens moving frame 1o in the optical axis direction.

However, in a configuration in which the lens is moved by rotating the operating ring (zoom ring) to rotate the cam barrel attached to the fixed barrel (2) and move the lens, assembly is extremely complicated due to its structure. There are also problems with the structure: it requires a large number of parts, and there is a limit to the miniaturization of the device.

(Objective of the Invention) The present invention has a small structure (fn) that is easy to assemble and reduces the number of parts required for the structure by introducing a planar cam mechanism that can move a lens with high precision. A lens moving device n is provided.

(Structure of the Invention) In order to achieve the above object, the lens moving device of the present invention has a variable power lens moving frame and a correction lens moving frame that are movable in the optical axis direction, and that are rotatable in a plane parallel to the optical axis. a possible drive force transmission part and contacting engagement with the drive force transmission part, respectively;
It consists of a connecting part provided on each of the lens movement frames, and an operation part provided on the variable magnification lens movement frame, and by operating the operation part, the magnification can be changed and the correction lens moved. Perform zooming by moving the frame.

This configuration simplifies assembly work, reduces the number of parts, and allows for -1 smaller size.

(Explanation of Examples) Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 2 shows the structure of a lens barrel in an embodiment of the present invention. In Figure 2 υ, 22 is
Focusing lens group A1 variable magnification lens group B1 correction lens group c1 and fixed lens D1 It is a board. 38 is a focusing lens holding frame, which is integrated with the lens substrate 22! It is fitted into the inner cylinder side of a retaining ring 39 formed by a connecting member 41, and is rotatably held by a connecting member 41. A cam (not shown) is formed on each end surface where the focusing lens holding frame 38 and the holding ring 39 come into sliding contact, so that it is impossible to rotate the focusing lens holding frame 38. is extended in the optical axis direction. Guide ball 36.
37 is positioned and supported by the lens substrate 22. The variable magnification lens moving frame 27 can be moved in the optical axis direction by inserting a tunnel ball 36 into the hole 27a and engaging a rotation prevention notch (not shown) with the guy 1-ball 37. It is supported. Similarly, the correction lens moving frame 2
8, the tunnel ball 37 is inserted into the hole 28a, and by engaging the rotation prevention notch 28b with the guide ball 3G, it can be supported movably in the optical axis direction.

23 is formed radially with respect to the center of rotation for moving the variable magnification lens moving frame 27 in the optical axis direction. 7
♂125 and a cam plate with a cam groove 26 for moving the correction lens moving frame 28 in the optical axis direction, which rotates on a shaft (old version in Fig. 3) embedded in the lens substrate 22. It is attached freely. The notch groove 27C formed in the variable magnification lens moving frame 27 has a protrusion 4 formed in the old operation part 48.
are engaged. An operation knob 47 is provided on the operation panel 48, which protrudes outward from an elongated hole 51 formed in the exterior 50 indicated by a dashed line and is movable in the optical axis direction. ing.

Further, in order to prevent dust from entering the camera body through the elongated hole 51, a dustproof plate 48a is provided to cover the elongated hole 51. 5 is a sectional view of the operating section side 48 as seen from the arrow 46 in FIG. 2, FIG. 6 is a cross-sectional view of the operating section 48 as seen from the arrow 55 in FIG. 2, and FIG. FIG. 3 is a cross-sectional view of the inner portion 48 as viewed from the arrow 54 in FIG. 2;

As shown in FIG. 6, the operating member 48 is housed in a long groove 53 provided in the exterior casing 50 so as to be slidable in the optical axis direction. Still as shown in FIG.
It is kited to be slidable in the optical axis direction by kite members 52a and 52b provided in the optical axis direction.

In FIG. 2, reference numeral 29 is a zoom motor, which is attached to a plate 30. The output of the zoom motor 29 is transmitted from the motor shaft 29a to the press-fitted motor gear 31, to the idler wheel 32, to the crown gear (not shown). 1), a friction mechanism (not shown) is transmitted by the drive gear 33 (and further transmitted to the cam plate 23 having teeth 24 formed on its end surface).

As a result, the cam plate 23 is rotated, and the modification lens moving frame 27 and the correction lens moving frame 28 are moved in the optical axis direction.

The operation of the lens moving device of this embodiment configured as described above will be explained in detail below. FIG. 3 is a flat tffj diagram showing the positional relationship between the cam plate 23, the variable magnification lens moving frame 27, and the correction lens moving frame 28 during wide-angle zooming, and FIG. 4 shows the cam plate during telephoto zooming. FIG. 3 is a plan view showing the positional relationship between the variable magnification lens moving frame and the correction lens moving frame. In FIG. Cutout for (
(not shown) to be movably supported in the optical axis direction. Similarly, a kite ball 37 is inserted into the hole 28a of the correction lens moving frame 28, and the guide ball 37 is inserted into the hole 28a.
G is supported so as to be movable in the optical axis direction by engaging a rotation prevention notch (not shown). A pin 42 implanted in the variable magnification lens moving frame 27 is engaged with a groove 25 formed radially with respect to the rotation center axis 40VC of the cam plate 23. Also, the cam groove 26Vc is the correction lens moving frame 2.
A cam follower 43 implanted in 8 is engaged. In FIG. 5, when the operating knob 47 is moved from the letter "W" 56 printed on the outer case 50 to the letter "T" 57, the protrusion of the operating member (49 in FIG. 2) causes a noise as shown in FIG. Notch groove 27c formed in variable power lens moving frame 27 engaged with
is urged in the direction of arrow 45. Therefore, the pin 7I2 presses the end face of the groove 25, and the cam plate 23 is rotated in the direction of the arrow 44 about the shaft 40-. Since the cam follower 43 moves into the cam groove 26 in the optical axis direction, the variable power lens moving frame 27 and the correction lens moving frame 28 move in the optical axis direction, thereby performing zooming. Move to the telephoto position shown in the figure.

It should be noted that although the above is a manual operation (C), it goes without saying that the cam plate 23 can also be rotated by motor drive, and the operations described in "2" can also be performed.

(Effects of the Invention) As is clear from the above description, the lens moving device of the present invention moves the variable power lens moving frame in the optical axis direction by operating the operation section provided on the variable power lens moving frame. At the same time, the zooming operation is performed by moving the auxiliary lens moving frame f via a cam plate that rotates in a plane parallel to the optical axis. This reduces the number of parts and greatly simplifies the assembly process. This has the advantage of being able to downsize the device itself.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a conventional lens moving device, Fig. 2 is a perspective view of an embodiment of the present invention, and Fig. 3 is a cam plate at a wide angle, a variable magnification lens moving frame, and a correction lens. FIG. 4 is a plan view showing the positional relationship of the moving frame, and FIG. The arrow 46 direction in FIG.
FIG. 7 is a cross-sectional view of the operating member viewed in the direction of arrow 54 in FIG. 2. 22... Lens board, 23...
・Cam plate, 25...00. Groove, 26...
. . . Cam groove, 27 . . . Variable magnification lens movement frame, 28 . . . Correction lens movement frame, 36.
37...Kite Hall, 42 songs/Pin, 43
...Cam follower, 47 Nakagawa...operation knob, 48...--operation member, 5o...
4. Exterior, A...Focusing lens group, B
・・・・・・Variable lens group, C・・・・・・・・・
・Auxiliary lens group. Patent applicant: Matsushita Electric Industrial Co., Ltd. Figure 3 Figure 4

Claims (1)

[Claims] A variable power lens moving frame and a correction lens moving frame whose optical axes coincide and are movable in the direction of the original axis, a driving force transmission member rotatable in a plane parallel to the original axis, and the variable power lens moving frame. and a connecting portion provided on each of the correction lens moving frames and contacting and engaging with the driving force transmission member, and an operating portion provided on the variable power lens moving frame, and the operating portion can be operated to change the magnification. By moving the lens moving frame in the optical axis direction, the correction lens moving frame is moved through the front drive force transmission unit. A lens moving device characterized in that it moves +.