JPH0510245Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to an attitude adjustment mechanism for adjusting the angle of the optical axis with respect to the disk surface in an optical pickup used in a playback device for video discs, audio discs, etc.

(Prior Art) Conventionally, as shown in FIG. 4, for example, as shown in FIG.
The pick-up 1 is supported so as to be slidable along the guide shaft 2 and rotatable around the guide shaft 2, and penetrated vertically to the other end of the pick-up 1, that is, the rotatable free end. The downward protruding end of the adjusting screw 3 is brought into contact with the upper surface of the guide rail 4 arranged and fixed in parallel with the guide shaft 2, and the leaf spring 13 is attached to the lower surface of the pick-up 1. This leaf spring 13 is connected in a cantilevered manner.
There is one in which the guide rail 4 is elastically held between the free end piece 13a and the lower end of the adjustment screw 3 from above and below. This adjustment mechanism adjusts the rotation of the pick-up 1 around the guide shaft 2 with respect to the guide rail 4 by adjusting the adjustment screw 3 downward.
The angle can be adjusted.

However, in the above conventional structure, the adjustment screw 3
The spring load changes as the amount of deformation of the leaf spring 13 increases or decreases as the spring moves forward and backward, and the sliding load between the lower end of the adjustment screw 3 and the free end piece 13a of the leaf spring and the guide rail 4 changes. It was hot.

Therefore, as the amount of downward protrusion of the adjustment screw 3 increases, the sliding resistance with respect to the guide rail 4 increases, and the sliding loss increases; conversely, as the amount of downward protrusion of the adjustment screw 3 decreases, rail 4
There was a problem in that the clamping load on the pick-up 1 decreased, and the posture stabilization function of the pick-up 1 deteriorated.

(Purpose of the invention) The present invention was made in view of the above-mentioned problems, and the purpose of this invention is to maintain a constant sliding load between the adjustment screw and the guide rail, regardless of the attitude adjustment of the pick-up using the adjustment screw. It is an object of the present invention to provide an attitude adjustment mechanism capable of reducing sliding resistance and stabilizing the attitude of a pick-up.

(Structure of the invention) In order to achieve the above-mentioned object, the present invention rotates an optical pick-up slidably provided on a guide shaft around the guide shaft.
In the attitude adjustment mechanism of the optical pickup, which adjusts the optical axis angle of the pickup, a guide rail having a pair of mutually opposing guide surfaces is provided in parallel on the free rotation end side of the optical pickup; An adjustment screw with a driven wheel is screwed through the free rotation end of the optical pick-up along the rotation direction, and both ends of the adjustment screw can be slid on each guide surface of the guide rail. It was supported by contact.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings. FIG. 1 shows a first embodiment of the attitude adjustment mechanism for an optical pickup according to the present invention.

The optical pickup 1 is provided with an optical signal input/output section 1a on the top surface. This pick up 1
has a guide shaft 2 passed through it at one end, and can be driven horizontally along the guide shaft 2 by appropriate driving means and rotated around the guide shaft 2.

A guide rail 4 is arranged parallel to the guide shaft 2 on the other end side of the pickup 1, that is, on the free rotation end side. This guide rail 4 has a U-shaped cross section and has guide surfaces 4a and 4 that face each other vertically.
It has b. Further, an adjustment screw 3 is screwed vertically through the free rotation end of the pick-up 1, and its upper and lower ends are abutted and supported by opposing guide surfaces 4a and 4b of a guide rail 4, respectively. There is.

A passive gear 5 is fixed to the upper part of the adjustment screw 3 as a passive wheel in response to a rotational operation force, and a transmission gear 6 that meshes with the passive gear 5 is connected to the upper part of the pickup 1 via a support shaft 7. Equipped with adjustable rotation. By adjusting the rotation of this transmission gear 6 with a driver 8, the adjustment screw 3 is moved forward or backward, thereby relatively rotating the pick-up 1 around the guide shaft 2, thereby inputting and outputting optical signals. The angle of the optical axis P of the portion 1a is adjusted.

In the above configuration, the opposing guide surfaces 4a,
4b and the length of the adjustment screw 3 must match correctly, and highly accurate dimensional control is required. In addition, if an unexpected external force acts on the guide rail 4 after assembly and causes a dimensional change, the adjustment screw 3
There is also a risk that the sliding resistance between the guide rail 4 and the guide rail 4 will increase, or that vertical backlash may occur.

FIG. 2 shows another embodiment that eliminates the drawbacks of the above embodiment.

In this example, the adjustment screw 3 has a screw body 3a which is threaded through the pick-up 1, and a head portion 3 which is inserted into the upper end of the screw body 3a and connected to the screw body 3a so as to be vertically telescopic.
It consists of b. A non-circular fitting hole 9 is bored in the upper end of the screw body 3a, and the head portion 3b is provided with a shaft portion 10 that fits into the fitting hole 9.
Both 3a and 3b are connected to be able to rotate together, and a coil spring 11 is inserted between both 3a and 3b, and with the coil spring 11 appropriately compressed, the adjustment screw 3 is inserted between the upper and lower guide surfaces 4a and 4b. It can be done.

Further, a passive gear 5 is fixed to the head portion 3b, and a driver 8 equipped with a transmission gear 6 that meshes with the passive gear 5 is positioned and fitted into a hole 12 formed on the top surface of the pick-up 1 to operate the transmission gear 6. The adjustment screw 3 can be adjusted by rotating the adjusting screw 3.

According to this configuration, even when adjusting the posture of the pickup 1, the sliding load between the adjustment screw 3 and the guide rail 4 is always constant, and the sliding load on the guide rail 4 is always constant.
There is no need to make the dimensional accuracy particularly high, and any dimensional changes after assembly will be absorbed by the coil spring 11.

(Effects of the invention) As described above, according to the invention, both ends of the adjustment screw screwed through the rotating free end of the pick-up are supported in contact with a pair of opposing guide surfaces of the guide rail. Therefore, even if the adjustment screw is moved forward or backward, the sliding contact load between the adjustment screw and the guide rail does not change, reducing the sliding loss of the pick-up.
It is now possible to perform stable sliding motion.

In this case, the adjustment screw will be covered by the guide surface of the guide rail, but since the adjustment screw is equipped with a passive ring, and the passive ring will protrude outside the guide rail, the adjustment screw can be covered without any problem. Entry/exit operations can be performed.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing an example of the attitude adjustment mechanism of the optical pickup according to the present invention;
The figures are a partially cutaway side view of another embodiment, FIG. 3 is an exploded perspective view of an adjustment screw, and FIG. 4 is a partially cutaway side view of a conventional example. 1...Optical pick-up, 2...Guide shaft,
3... Adjustment screw, 4... Guide rail, 4a, 4
b...Guide surface.

Claims (1)

[Claims for Utility Model Registration] (1) An optical pick-up that is slidably provided on a guide shaft is rotated around the guide shaft to adjust the optical axis angle of the pick-up. In the attitude adjustment mechanism of the optical pick-up, a guide rail having a pair of mutually opposing guide surfaces is provided on the free rotation end side of the optical pick-up, and a passive guide rail is provided on the free rotation end side of the optical pick-up. An optical type, characterized in that an adjustment screw with a ring is screwed through the screw along the rotational direction, and both ends of the adjustment screw are slidably abutted and supported on each guide surface of the guide rail. Pick-up posture adjustment mechanism. (2) The attitude adjustment mechanism for an optical pickup according to claim 1, wherein the adjustment screw is extendable and elastically biased in the direction of extension.