JPS61296537A - Actuator - Google Patents

Abstract

PURPOSE:To form an actuator with high drive efficiency and excellent vibration proof by using a link mechanism for the support in the focus direction. CONSTITUTION:A moving part 4 including a lens hold base 1 and a coupling body 3 is supported by a link mechanism (1st support mechanism 8) using the body 3 as a link rod. The 1st support mechanism 8 supports the moving part 4 with the support mechanism freely turnably in the focus direction and the 2nd support mechanism 9 supports the 1st support mechanism 8 with a support mechanism freely turnably in the tracking direction and then a lens 6 is driven in the focus and tracking directions. In driving the lens 6, since no sliding structure is employed, friction is very small and the drive efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an actuator used in an optical information recording/reproducing machine.

2. Description of the Related Art Actuators used in conventional optical regenerators are disclosed in Japanese Patent Application Laid-open No. 57-210456, for example.
The structure was as shown in Fig. 6(&)(b).

That is, the lens holding cylinder 18 is supported by the support shaft 2o by the bearing 19.
The structure was such that it slid in the focusing direction and rotated in the tracking direction. Also, no counterweight was provided.

Problems to be Solved by the Invention However, in the structure as described above, since the structure slides in the focus direction, frictional force is generated between the support shaft and the bearing during driving, reducing the driving efficiency. Further, in order to reduce frictional force, a certain amount of space is required between the support shaft and the bearing, but if the space is large, the structure becomes vulnerable to external vibrations. In other words, drive efficiency and vibration resistance are contradictory.

Bearings and support shafts were required to have high dimensional accuracy.0 Also, since the structure does not have a support point in the focus direction,
It was not possible to provide a counterweight in the focus direction.

Therefore, the present invention provides an actuator that has a support link mechanism in the focus direction and has high drive efficiency and good vibration resistance.

Means for Solving the Problems In order to solve the above problems, the actuator of the present invention includes a lens, a lens holder for holding the lens, a fixing part, and a support between the lens holder and the fixing part. A link mechanism is used to support at least the focusing direction of the lens.

Function: Due to the above-described configuration, the present invention does not use a sliding structure, so the frictional force is extremely small and the driving efficiency is high. Further, since the structure has a fulcrum in both the focus direction and the tracking direction, one counterweight can be used effectively in both the focus direction and the tracking direction, and vibration resistance can be improved.

Note that since a link mechanism is used for support in the focus direction, the optical axis of the lens does not tilt.

Example: Figure WJ shows an actuator according to an example of the present invention.
I will explain while referring to .

FIG. 1 is a diagram showing the structure of an actuator in a first embodiment of the present invention.

In FIG. 1, 1 is a lens holding base, 3 is a combination body, a movable part 4 including the lens holding base 1 and the combination body 3, and a link mechanism (first support mechanism 8) using the combination body 3 as a link rod. Supported.

The first support mechanism 8 is a support mechanism that is rotatable in the focusing direction and supports the movable part 4, and the second support mechanism 9 is a support mechanism that is rotatable and movable in the tracking direction and supports the first support mechanism 8. However, this allows the lens 6 to be driven in the focusing direction and the tracking direction.

As described above, according to this embodiment, since the lens 6 does not have a sliding structure when being driven, the frictional force is extremely small and the one-drive efficiency is high.

An actuator according to a second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows the structure of an actuator in a second embodiment of the invention.

In FIG. 2, 1 is a lens holding base, 3 is a combination body, 4 is a movable part, and 5 is a fixed part, which are the same as those in FIG. 1.

What is different from the configuration shown in Figure 1 is the combination body 3 and lens holder 1.
and the point where the fulcrum with the fixed part 6 is connected using the elastic support material 16.

As mentioned above, the combined body 3, the lens holder 1 and the fixing part 5
By connecting the fulcrum with the fully elastic supporting member 16, a restoring force is generated against the displacement of the lens, and a neutral point holding mechanism is constructed. Further, the second support mechanism 9 in FIG. 1 can also be constructed by a link mechanism using the combined body 3, and the two support mechanisms 8 and 9 in FIG. 1 can be constructed by one support mechanism 17.

An actuator according to a third embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows the structure of an actuator in a third embodiment of the invention.

In FIG. 3, 1 is a lens holding base, 3 is a combination body, 4 is a movable part, 8 is a first support mechanism, and 9 is a second support mechanism, which are similar to those in FIG. 1.

What is different from the configuration shown in FIG. 1 is that the combination body 3 is extended from the fixing part 6 in the opposite direction to the lens holder 1, and a counterweight 2 designed to balance the mass is provided on the extension part of the combination body 3. This is the point.

As described above, by extending the combined body 3 and providing the counterweight 2, the counterweight 2 can be made effective in both the focusing direction and the tracking direction, and vibration resistance can be improved.

In this case, the center of gravity of the movable part 4 including the lens holding base 1, counterweight 2, and combination body 3 is on a plane that includes the fulcrum 16 of the combination body 3 and the first support mechanism 8, and on the second support mechanism 9.
The counterweight 2 is provided so as to be on the support shaft 11 of the counterweight 2.

An actuator according to a fourth embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 shows the structure of an actuator in a fourth embodiment of the present invention.

In FIG. 4, 1 is a lens holding base, 3 is a combination body, 4 is a movable part, and 6 is a fixed part, which are the same as those shown in FIG. 1.

What is different from the configuration shown in FIG. 1 is that the combination body 3 is extended from the fixing part 5 in the opposite direction to the lens holder 1, and a counterweight 2 designed to balance the mass is provided on the extension part of the combination body 3. , is the point where the fulcrums of the combined body 3, the lens holder 1, the fixing part 6, and the counterweight 2 are connected using the elastic support member 16.

As described above, this embodiment is a combination of the first embodiment and the second embodiment of the present invention, and has the effects of both.

In this case, the counterweight 2 is placed so that the center of gravity of the movable part 4 including the lens holding base 1, the counterweight 2, and the combined body 3 is on a plane that includes the fulcrum 16 of the combined body 3 and the fixed part 6.
should be established.

In addition, in the description of all the above embodiments, it is assumed that the lens 6 is included in the lens holder 1.

Further, in FIGS. 3 and 4, reference numeral 12 denotes a drive means, which is composed of a drive coil 13 provided on the movable part 4 and a fixed magnetic yoke 14, and drives the movable part 4 in the focusing direction and the tracking direction. It is.

Effects of the Invention As described above, the present invention can provide an actuator with high drive efficiency and good vibration resistance by using a link mechanism for support in the focus direction and eliminating a sliding structure.

Further, with a simple structure, one counterweight can be used in both the focusing direction and the tracking direction, and an actuator with good vibration resistance can be provided.

Furthermore, it is possible to provide an actuator that is easy to process and does not require high dimensional accuracy unlike the support shaft and bearing of a conventional actuator.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of an actuator according to a first embodiment of the invention, FIG. 2 is an external perspective view of an actuator according to a second embodiment of the invention, and FIG. 3 is a third embodiment of the invention. FIG. 4 is an assembled perspective view of the actuator in the fourth embodiment of the present invention, FIG. 6 is an assembled perspective view of the conventional actuator, and FIG. 6 (2L) (b) is the conventional actuator. FIG. 3 is a plan view and a vertical cross-sectional view of the actuator. DESCRIPTION OF SYMBOLS 1... Lens holding stand, 2... Counterweight, 3... Combined body, 4... Movable part, 18... Lens holding Cylinder, 20...Spindle. Name of agent: Patent attorney Toshio Nakao and 1 other personf Figure 2

Claims (3)

[Claims] (1) The lens includes a lens, a lens holder that holds the lens, a fixing part, and a combination body that uses a link mechanism to support at least the focus direction between the lens holder and the fixing part. An actuator featuring: (2) The actuator according to claim 1, further comprising an elastic support member that elastically supports each fulcrum of the link mechanism. (3) The combined body extends from the fixing part in a direction opposite to the lens holder, and the extended part of the combined body is provided with a counterweight designed to balance the mass. Or the actuator according to item 2.