JPH02273383A - Movable member holding mechanism for optical head - Google Patents

Abstract

PURPOSE:To suppress the injurious vibrations caused by the looseness produced between a rail and the sleeves by providing a magnetic attraction means fixed at a position opposite to a guide rail composed of a ferromagnetic substance and set on an optical head movable member. CONSTITUTION:A movable member 1 composed of an optical head or a part of this head is held by a main rail 6 composed of a ferromagnetic substance fixed to the enclosure 5 of an optical disk through two sliding sleeves 3 and 4. The member 1 is also held by a subrail 7 arranged in parallel with the rail 6 via the sliding pads 8 and 9. Then a magnetic attraction means 10 is fixed on the member 1 between both sleeves 3 and 4 and at a position opposite to the rail 6. Consequently, the sleeves 3 and 4 are pressed in a single direction to the rail 6 as long as the means 10 is working. Thus it is possible to suppress the injurious vibrations due to the looseness caused between the rail 6 and both sleeves 3 and 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical head movable member holding mechanism for an optical disc device.

[Conventional technology]

Conventionally, an optical head movable member holding mechanism of an optical disc device has been supported by a bearing in which a bearing fixed to a movable member rolls into contact with a guide rail fixed to an optical disc housing. In addition, sliding bearing support has also been used in which a sliding member fixed to a movable member slides into contact with the guide rail.

The bearing support is achieved by, for example, bringing a movable member into contact with two parallel round rails fixed to an optical disc device housing, and a bearing properly arranged and fixed so as to have a rolling direction along the rails. Realized. Furthermore, by having a structure in which one of the bearings is pressed against the rail with an appropriate preload, smooth running without play is possible.

On the other hand, the sliding bearing support may include, for example, arranging two sliding sleeves that fit into the round rail fixed to a movable member with respect to one round rail fixed to the optical disc device housing, and furthermore, Two sliding members fixed to a movable member are arranged to sandwich the flat rail with respect to one flat rail that is arranged parallel to the rail and whose thickness direction is the circumferential direction of the round rail. ing.

[Problem to be solved by the invention]

However, the conventional optical head movable member holding mechanism described above is
The bearing support is complicated because the bearing itself has a complicated structure and it is necessary to use a large number of bearings with high precision.

It has the disadvantage of being expensive.

On the other hand, the above-mentioned sliding bearing support has the disadvantage that vibrations are likely to occur in the movable member due to play between the rail and the sliding sleeve.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to provide an inexpensive optical head movable member holding mechanism that is free from backlash.

[Means to solve the problem]

The optical head movable member holding mechanism of the present invention is an optical head movable member holding mechanism that supports a movable member consisting of an optical head of an optical disk device or a part thereof movably along the surface of an optical disk medium. a sliding member fixed to the movable member; and a sliding member fixed to the casing of the optical disc device;
It has a guide rail made of a ferromagnetic material that is in slidable contact with the sliding member, and a magnetic attraction means fixed on the movable member at a position facing the guide rail.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is three drawings schematically showing an embodiment of the present invention.

A movable member 1 consisting of an optical head or a part thereof is fixed to the casing of an optical disc device by two sliding sleeves 3 and 4 having cylindrical sliding inner surfaces having the same axis and the same diameter. It has a diameter slightly smaller than the inner diameter of the sliding sleeves 3 and 4 that are fixed to the body 5 through the two sliding sleeves 3 and 4, and is held by a main rail 6 made of a ferromagnetic material. . Moreover, the movable member 1 has a thickness direction of the sub-rail fixed to the movable member 1, with respect to a sub-rail whose thickness direction is the circumferential direction of the main rail 6, which is arranged parallel to the main rail 6. The gap direction is defined as the gap distance, and the gap distance is set to be slightly larger than the above-mentioned thickness, and it is held by two sliding pads 8 and 9 arranged to sandwich the sub-railway.

Further, a magnetic attraction means 10 is fixed on the movable member 1 at a position facing the main rail 6 between the two sliding sleeves 3 and 4. The magnetic attraction means 10 is composed of an electromagnet or a permanent magnet.

With the above configuration, while the magnetic adsorption means 10 is operating, the sliding sleeves 3 and 4 are pressed against the main rail 2 in one direction, and due to the backlash between the main rail 2 and the sliding sleeves 3 and 4. Vibration of the movable member 1 can be suppressed. Further, by using a sliding sleeve instead of a bearing, the structure of the optical head movable member holding mechanism is simplified and the cost can be kept low.

Further, also in the sliding portion constituted by the sub-railway and the two sliding pads 8.9, backlash can be easily prevented by magnetic means similar to the above structure. Alternatively, one of the two sliding pads 8.9 may be pressed against the sub rail by a spring.

Furthermore, if an electromagnet is used as the magnetic adsorption means 10, the electromagnet is operated only when it is necessary to reduce the influence of backlash, such as when writing with an optical head, and the preload is applied to operate the electromagnet when the head is moved. By reducing the frictional force caused by this, it is possible to improve access performance and extend the life of the sliding bearing.

〔Effect of the invention〕

As explained above, the present invention has a simple structure for holding a movable member using a guide rail and a sliding sleeve, thereby suppressing an increase in price, and also uses a magnetic means to connect the guide rail and sliding sleeve. By eliminating the backlash, it is possible to realize an optical head movable member holding mechanism with a simple structure that suppresses harmful vibrations caused by the backlash.

Furthermore, by using an electromagnet as the magnetic means, the electromagnet is activated only when necessary, such as when writing information,
This has the effect of ensuring accuracy, reducing friction by not activating the electromagnet at other times, improving access performance, and extending the life of the plain bearing.

[Brief explanation of drawings]

FIG. 1 is a three-sided view schematically showing an embodiment of the present invention. 1... Movable member, 3, 4... Sliding sleeve, 5... Housing, 6... Main rail, 7... Sub-rail, 8, 9...Sliding pad, 10...Magnetic adsorption means. Agent Patent Attorney Susumu Uchihara

Claims (1)

[Scope of Claims] An optical head movable member holding mechanism that movably supports a movable member consisting of an optical head or a part thereof of an optical disc device along an optical disc medium surface, comprising a movable member and a slide fixed to the movable member. a movable member, a guide rail made of a ferromagnetic material fixed to the housing of the optical disk device and slidably in contact with the sliding member, and a magnetic material fixed at a position facing the guide rail on the movable member. An optical head movable member holding mechanism comprising: suction means.