JPS60216320A - Lens moving device - Google Patents

Abstract

PURPOSE:To facilitate assembly by using a plane cam mechanism for lens movement, releasing one terminal of a cam groove, and providing a flexible projection member to the release part. CONSTITUTION:A cam plate 38 is inserted along guide members 31a, 31b, and 31c as shown by an arrow 49. At this time, a projection 31d formed on a lens substrate 31 enters the recessed part 43 of the cam plate 38. Cam followers 41 and 42 press flexible projection members 51 and 52, which flex; when the cam plate is inserted gradually, the cam followers 41 and 42 engage grooved cams 39 and 40 respectively. In this state, the cam plate 38 is supported movably from where the cam followers 41 and 42 abut on the flexible projection members 51 and 52 to where the projection 31d of the lens substrate 31 abuts on a wall 43a formed in the recessed part 43 of the cam plate 38.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a lens moving device that is effective for use in video cameras and the like.

Conventional Structure and Its Problems A conventional zooming mechanism for a lens barrel generally uses a cam barrel attached to a fixed barrel to perform one-noise movement. This will be explained with reference to FIG. FIG. 1 is a partial cross-sectional view of the main parts of a conventional example of the Zoom 1 Non-Z mW4. 1 is a fixed barrel, 2 is a focus ring, and the focus ring 2 is attached to a helicoid screw 1a provided on the fixed barrel 1. The set helicoidal screw 2a is screwed together and rotated around the optical axis, thereby extending the focusing lens 1-1°L2.1.3 in the optical axis direction. Second lens L4, 1-5. L6 is inserted into the first lens holding frame 8, and the second lens 1.L6 is inserted into the first lens holding frame 8. ．． -2 screw part 9a of presser foot 9 in step 4
- It is fixed to the first lens holding frame 8 by screwing into the threaded portion 8a of the first lens holding frame 8.

The third lens L7 is inserted into the second lens holding frame 10, and is fixed by being pressed by the presser ring 11 of the third lens L7. The first and second lens holding frames 8.10 are fitted into guide balls 6.7 whose base ends are supported by the fixed barrel 1. 5 is a first cam 14 for moving the first lens holding frame 8 and the second lens holding frame 10 in the optical axis direction.
It is a cam cylinder with a second cam groove 15 provided on the circumferential surface in a direction intersecting the optical axis direction, and the ball supporting plate 11 that supports the tip of the guide ball 6.7 on the fixed cylinder 1 allows the guide ball 6. Location is restricted. In the first cam groove 14 and the second cam groove 15, second lenses L4 and l5.
1.6 and the third lens [-7 on the optical axis L1
For this purpose, the cam followers 12, 13 of the first lens holding frame 8 and the second lens holding frame 10 are engaged.

Further, a bottle 16 is implanted in the cam cylinder 5, and the bottle 16 passes through a long groove 18 in the circumferential direction perpendicular to the optical axis direction, which is bored in the fixed cylinder 1, and protrudes to the outside of the fixed cylinder 1. -3- Yes. Reference numeral 19 denotes a zoom ring into which a zoom gear 20 is fitted so as to be rotatable around the optical axis, and a pin 16 is engaged with a long groove 21 in the optical axis direction formed on the inner circumferential side. That is, when the zoom ring 19 is rotated by the operation knob 22, the pin 16 engaged with the long groove 21 is driven and the cam cylinder 5 is rotated, so that the first lens holding frame 8 and the second lens holding frame 8 are rotated.
The second lens L4 in the lens holding frame 10. L5. L
6 and the third lens L7 are in the same position as the first cam groove 14 and the second cam groove 14.
Zooming is performed while being regulated by a cam groove 15.

However, in the above configuration, the assembly involves connecting the first and second balls to the fixed f11 via the guide balls 6.7.
After supporting the lens holding frame 8.9, the cam cylinder 5 is inserted and the cam m5 is held by the ball support plate 17. Then, the first and second lens holding frames 8.9 are moved to predetermined positions, and the cam follower 12.13 is moved to the first and second positions through through holes (not shown) appropriately provided in the fixed barrel 1. This requires a step of attaching it to the lens holding frames 8 and 9, which poses a problem in that assembly requires skill.

-4- Purpose of the Invention The present invention introduces a planar cam mechanism to move the lens, and by opening at least one end of the cam groove, assembly is facilitated and the structure is simplified. The purpose is to provide a device.

Structure of the Invention In order to achieve the above object, a lens moving device of the present invention includes a first lens holding frame and a second lens holding frame movable in the optical axis direction.
a lens holding frame, a first cam follower provided on the first lens holding frame, a second cam follower provided on the second lens holding frame, and a second cam follower that engages with the first cam follower. and are arranged in a direction intersecting the optical axis direction in a plane parallel to the optical axis, and are open at least on one end side and have a flexible protruding member in this open part, a first full cam movable in a direction orthogonal to the second cam follower, and disposed in a plane parallel to the optical axis in a direction substantially intersecting the optical axis direction;
At least one end side is opened, and this opening part has a flexible protruding member, and a second grooved cam movable in a direction substantially perpendicular to the optical axis direction. Accordingly, assembly becomes easy, and a compact and inexpensive lens moving device can be obtained.

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

FIG. 2 is a perspective view of a main part of a lens moving device according to an embodiment of the present invention, and FIG. 3 is a plan view of the main part.

The lens substrate 31 is the lens group A.

Second lens group B1 Third lens group C1 Fixed lens D1 Aperture 34, Master lens group E1 Aperture 32 and Filter 3
These are members for attaching 0 to each.

Further, the lens substrate 31 includes guide members 31a, 31b,
31c and a protrusion 31d are formed. The second lens holding frame 10 holds the lens group, and the second lens holding frame 3
4 holds the second lens group B, and the third lens holding frame 35 holds the third lens group C. Second lens holding frame 34
is inserted into the guide ball 6-36 supported by the lens substrate 31 through the hole 34a, and engaged with the guide ball 37 supported by the lens male plate 31 via a rotation prevention notch (not shown). Particularly C lens substrate 31
It is movably supported in the optical axis direction 50 at the top. Similarly, the third lens holding frame 35 also has a hole 35a in the guide ball 31.
The guide 1 is inserted through the pole 36 through the anti-rotation notch 3h and is supported so as to be movable in the optical axis nozzle direction i at the lens base 311 by engaging with the pole 36. Reference numerals 6 and 38 are cam plates, and the first grooved cam 39 moves the second lens holding frame 34 in the optical axis direction j)0.
And the third lens holding frame 3! ) in the optical axis direction! A second full cam 40 for moving to IO is formed in a direction intersecting the optical axis direction. A first open part 39a is formed at one end of the first full cam 30, a second open part 40a is formed at one end of the second grooved cam 40, and the first open part 39a is formed at one end of the second groove cam 40.
A has a flexible protruding member 51, and a second g! 1 scattered part 4Q
A flexible protrusion @52 is formed at a. The cam plate 38 is a guide member 3 formed on the lens substrate 31.
1a, 31b, and 31c so as to be movable in the direction of arrow 49.

-7- A first cam follower 41 provided on the second lens holding frame 34 engages with the first full cam 39, and a second cam follower 41 provided on the third lens holding frame 35 engages with the second groove cam 40. cam follower 42 is engaged. Also, on the back side of the cam plate 38, there is a third
Four portions 43 indicated by broken lines in the figure are formed, and the protrusion 31d of the lens substrate 31 will be located within this recess 43 after assembly.

The zoom motor 46 is supported by the lens substrate 31,
A motor pinion 47 press-fitted into the cover 11 foot (not shown) meshes with a rack 48 formed on the cam plate 38.

The operation of the lens moving device of this embodiment configured as described above will be explained below. FIGS. 4 and 5 are plan views of essential parts for explaining the operation.

In FIG. 4, a second lens holding frame 34 and a third lens holding frame 35 are supported on the lens substrate 31 so as to be movable in the optical axis direction 50 by guide balls (not shown), and a cam plate 38 is attached. The steps to do this are as follows. First, the cam follower 41 provided on the second lens holding frame 34 and the cam follower 42 provided on the third lens holding frame 35 are inserted into the open portion 39a of the first full cam 39 of the cam plate 38 and the second groove. The cams 40 are moved to positions where they engage with the opening portions 40a of the cams 40, respectively. Next, while aligning the cam plate 38 with the guide members 31a, 31b, and 31c, follow the arrow 49.
Insert in the direction of At this time, the protrusion 31d formed on the lens substrate 31 enters into the four parts 43 of the cam plate 38.

The cam follower 41.42 has a flexible projection member 51.5.
Press the cam plate 2 to bend it, and move the cam plate 3 to the position shown in Figure 5.
8, the cam holders 41 and 112 will engage with the groove cams 39 and 40, respectively. In this state, the cam plate 38 is attached to the cam followers 41 and 42 shown in FIG.
The cam plate 38 is supported so as to be movable from a position where the flexible protrusion members 51 and 52 abut, to a position where the protrusion 31d of the lens substrate 31 and the wall 43a formed in the recess 43 of the cam plate 38 abut, as shown in FIG. That will happen. Next, motor binion 4
A zoom motor 46 supporting a zoom lens 7 is attached to the lens substrate 31, and the motor binion 47 is engaged with a rack 48 formed on the cam plate 38. As a result, the rotation of the zoom motor 46 is transmitted to the cam plate 38, the cam plate 38 moves in the direction of the arrow 49, and the cam follower of the second lens holding frame 34 engaged with the full cam 9-39.
41 and the third lens holding frame 3 engaged with the second grooved cam 40
5 cam followers 42 are driven in the optical axis direction 50.

As described above, according to this embodiment, a lens moving device that is easy to assemble can be realized by forming an open portion at at least one end of the grooved cam.

In addition, by using a flat cam, it is possible to easily mold a high-precision cam, and compared to a conventional cam tube attached to a fixed barrel that moves the lens, it is possible to mold the cam with 1lf
It is possible to implement a small and inexpensive lens moving device.

In the above embodiments, the flexible protruding member is integrally formed with the cam plate, but the flexible protruding member may be formed as a separate member. 4. In the above embodiments, a cam plate with grooves formed in the plate was explained, but any structure may be used as long as it has a function of guiding a cam follower. For example, as shown in FIG. It is also possible to form a wall cam 39'4G' to guide the movement.

-10- Effects of the Invention As is clear from the explanation below, the present invention has J.
Assembling, which conventionally required skill, can be performed very easily, and it is possible to realize a compact and inexpensive lens moving device with a simplified configuration. In addition, by using a flat cam, it is easy to form the lens, which improves the productivity, compared to 1), which is attached to a conventional fixed barrel and uses an Iζ cam tube to move the lens. It is possible to reduce the weight.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side sectional view showing a conventional zoom lens barrel, FIG. 2 is a perspective view of the drinking part of a zoom lens barrel according to an embodiment of the present invention, and FIG. FIGS. 4 and 5 are plan views of essential parts for explaining the operation, and FIG. 6 is a perspective view showing a cam plate in another embodiment of the present invention. 31... Lens substrate, 33, 34. 35... 1st ~
Third lens holding frame, 36.37... guide ball,
38... cam plate, 39, 40... first and second grooved cams, 39a, 40a...) cam opening part, 41.42
...Power 11 Follower, 46...Zoom mode 11
- Ichita, 47...Motor bin, 51.52...Protrusion member agent Yoshihiro Morimoto 12-

Claims (1)

[Claims] 1. A first lens holding frame and a second lens holding frame that are movable in the optical axis direction, and a first cam frame A [1 a second cam follower mounted on the second lens holding frame; a second cam follower that engages with the first cam follower; and a direction intersecting the optical axis direction on a plane parallel to the optical axis. a first grooved cam that is disposed in the cam and has at least one end opened, has a flexible protruding member in the open part, and is movable in a direction substantially perpendicular to the optical axis direction, and is engaged with the cam follower. and is arranged in a direction intersecting the optical axis direction on a plane parallel to the optical axis, and at least one end side is open, and this open part has a flexible protrusion member, and the optical axis direction A lens moving device comprising a second groove cam movable in substantially orthogonal directions. -1-2. The lens moving device according to claim 1, wherein the first grooved cam and the second grooved cam are formed on the same cam plate.