JPH0490172A - Carriage guiding device - Google Patents

Abstract

PURPOSE:To inexpensively improve the frequency characteristics of a carriage by forming a part or the whole of a shaft connecting the carriage to a bearing by an elastic member. CONSTITUTION:An optical pickup 1 is mounted on the carriage 2, which is supported at least by six bearings 3a to 3d or more through bearing shafts 4a to 4d and the bearings 3a to 3d are supported by guide members 6, 7. In this case, an elastic member is used for the bearing shafts 4a to 4d. Consequently, a pressure applying member such as a plate spring causing unnecessary subresonance for frequency characteristics can be omitted, a carriage unit can be simplified and control characteristics or the like can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is applied to, for example, a carriage guide device in a drive system of an optical disk device.

[Prior Art] For example, in order to move an optical pickup for reading and writing information to any position in the radial direction on an optical disk, a carriage mechanism as shown in FIGS. 6 and 7 is conventionally used. It is being Figure 6 is a side view of the carriage mechanism;
FIG. 7 is a bottom view seen from the direction AA in FIG. 6, and the optical pickup 1 is mounted on a carriage 2 that moves in the radial direction of the optical disc. At least six or more ball bearings 3a to 3d are used as bearings in the carriage 2, and the bearings 3a to 3d are attached to bearing shafts 4a to 4d with high rigidity made of stainless steel or the like. 48
4c are fixed to the carriage 2 by press fitting, screwing, etc.

Also, for example, bearing 3d is bearing shirt 1-4.
By pressing the bearing 3d in the direction of the arrow, the bearing 38-3c is fixed to the leaf spring 5 via the leaf spring 5. ing.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional example, since the plate spring 5 takes up the looseness of the bearing relative to the guide member 6.7, the natural vibration of the plate spring 5 increases the frequency of the entire carriage 2. This occurs as sub-resonance in the characteristics, and has an adverse effect on the control characteristics of the carriage 2.

SUMMARY OF THE INVENTION An object of the present invention is to provide a carriage guide device that eliminates the above-mentioned drawbacks and improves the frequency characteristics of the carriage while being low in cost.

[Means for Solving the Problems] In order to achieve the above-mentioned object, a carriage guide device according to the present invention includes a carriage mounted with an optical pickup that moves linearly, and a carriage that linearly guides the movement of the carriage. It is characterized in that it comprises a guide member and a plurality of bearings that are in contact with the guide member and support the carriage, and that at least one shaft that connects the carriage and the bearing is partially or entirely formed of an elastic member. It is something.

[Operation] The carriage guide device having the above-mentioned configuration improves the frequency characteristics of the carriage by using a slack-removal mechanism in which the shaft is formed of an elastic member.

[Example] The present invention will be described in detail based on the illustrated example. Note that the same reference numerals as in the conventional example represent the same members.

FIG. 1 shows a side view, in which the optical pickup 1 is placed on a carriage 2, and the carriage 2 is supported by at least six or more bearings 38 to 3d, including bearings not shown, via bearing shafts 4a to 4d. ,
Furthermore, the bearings 3a-3d are supported by guide elements 6.7. Here, an elastic material is used for the bearing shafts 4a to 4d in order to eliminate play in the bearings 3a to 3d relative to the guide member 6.7.

FIG. 2 shows an enlarged cross-sectional view of the bearing 3a and the bearing shaft 4a. The pin 8 is insert-molded and integrated into one end of the bearing shaft 4a, and the other end of the bearing shaft 4a is press-fitted into the inner ring of the bearing 3a. The bottle 8 is press-fitted into a hole in the carriage 2.

In the embodiment shown in FIG. 3, a metal pin 9 is press-fitted into the bearing 3a, while the pin 9 and the bearing shaft 4a made of an elastic material are integrally formed by molding or the like, and the other end of the bearing shaft 4a is carriage 2
It is press-fitted inside.

In FIG. 4, metal bottles 10.11 are press-fitted into the bearing 3a and the carriage 2, respectively, and a bearing shaft 4a made of an elastic material connected by molding or the like is attached between the bottles 10.11. ing.

In the embodiment shown in FIG. 5, a bearing shaft 4a made of the same material is protruded from the outer casing of the carriage 2 made of an elastic material and is press-fitted into the bearing 3a. By doing this, the bearing shaft 4a, the bearing shaft 4a,
This leads to a reduction in the weight of the entire carriage 2 and a reduction in the size of the motor for driving the carriage 2, resulting in a significant cost reduction.

In this way, the shapes of the parts constituting the bearing shaft 4 and the carriage 2 are not limited to the embodiments, but the shapes of the parts that connect the bearing 3 and the carriage 2 are small (both in one place,
An elastic material made of a mold or the like may be present.

In FIG. 1, at least one portion of each bearing 38-3d and bearing shaft 48-4d is constructed as shown in any one of FIGS. 2-5. Here, the bearing shaft 4 of the bearing 3d is not assembled with the bearings 3a to 3d and the guide member 6.7.
An elastic material is used for d, and the bearing 3d is arranged so that a point P on the outer peripheral surface of the bearing 3d is slightly inside the outer diameter of the guide member 7. In this state, bearing 3a
When ~3d is combined with the guide member 6.7, only the bearing shaft 4d of the bearing 3d is elastically deformed and receives a force in the direction of the arrow. Conversely, when viewed from the carriage 2 side, the bearing 3d is pressed against the guide member 7,
It is possible to eliminate looseness between the bearings 3a, 3b, 3c and the guide members 6.7.

By using the bearing shafts 4a to 4d having such a shape, it is possible to avoid generating unnecessary sub-resonance near the zero crossing in terms of the frequency response of the carriage 2, and it is possible to obtain good control characteristics.

Note that even if the bearing shaft 4 made of an elastic material is provided at only one location, a considerable effect can be obtained.

[Effects of the Invention] As explained above, the carriage guide device according to the present invention eliminates the cause of unnecessary sub-resonance in terms of frequency characteristics by composing a part or the whole of the bearing shaft that connects the carriage and the bearing with an elastic material. It is possible to omit a preload member such as a leaf spring, which has the effect of simplifying the carriage unit and improving control characteristics.

[Brief explanation of drawings]

Drawings 1 to 5 show an embodiment of the carriage guide device according to the present invention, in which Fig. 1 is a side view of the carriage unit, and Sections 2 to 5 are enlarged sectional views of essential parts, respectively.
FIG. 6 is a side view of a conventional carriage unit, and FIG. 7 is a bottom view seen from the direction AA in FIG. 6. 1 is an optical head, 2 is a carriage, 38 to 3d are bearings, 48 to 4d are bearing shafts, 6.7 is a guide member, and 8.9.10.11 is a bottle. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] 1. A carriage mounted with an optical pickup that moves linearly, a guide member that linearly guides the movement of the carriage, and a plurality of bearings that contact the guide member and support the carriage, the carriage and the bearings 1. A carriage guide device, characterized in that at least one shaft connecting the carriage is partially or entirely formed of an elastic member.