JPH01224981A - Head feeding mechanism for information recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce the friction between a carriage and a lead screw by installing an antifriction bearing in a carriage guided in the radial of a cylindrical information recording medium by the lead screw and engaging the lead screw in the rotor part of the antifriction bearing. CONSTITUTION:An antifriction bearing 100 is installed in the carriage guided in the radial of a disk-shaped information recording medium by a lead screw 14, and the lead screw 14 is engaged in the rotor (an inner ring 15) of the antifriction bearing 100. Thus, since the antifriction bearing 100 at the side of the carriage also rotates accompanying the rotation of the lead screw 14 when the carriage, on which a head is loaded, is sought in the radial of the surface of the information recording medium, the frictional force between the carriage and the lead screw 14 can be made smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a head feeding mechanism for an information recording/reproducing device.

[Conventional technology]

Prior to explaining the present invention, a conventional example of a head feeding mechanism for an information recording/reproducing device will be explained based on FIG. 6. In the figure, a lower head 1 is adhesively fixed to a carriage 2, and an upper head 3 is glued to arm 4,
The upper and lower heads 1 and 3 are fixed to the carriage 2 via a spring plate 5 after alignment. Also, carriage 2
is guided by a first guide shaft 6 in the radial direction of a disc-shaped information recording medium (not shown). Reference numerals 7 and 8 each indicate a guide hole provided in the carriage 2, that is, a guide hole for guiding the first guide shaft 6 when the head mounting carriage 2 seeks in the radial direction of the disc-shaped information recording medium.

Further, the second guide shaft 9 guides the upper and lower heads 1 and 3 to keep them horizontal with respect to the medium surface of the disc-shaped information recording medium.
A lead screw 14 is formed in the screw groove.

The protrusion 11 of the arm 1o, which was molded at the same time as the carriage 2, is pressed by a spring plate 12, and the carriage 2
position. Furthermore, the second guide shaft 9
It is directly connected to the rotating shaft of the stepping motor 13, and when the head mounting carriage 2 is sought in the radial direction of the information recording medium, the stepping motor 13 rotates to cause the carriage 2 to reciprocate.

[Problem to be solved by the invention]

In the above configuration, the carriage 2 when the stepping motor 13 is operated in a mask step operation to increase the angle to a certain level and then return to the original angle.
When measuring the moving distance, hysteresis characteristics occur on the way out and on the way back, as shown in FIG. The reason for this is that in order to move the carriage 2, the guide shaft 9 needs to rotate against the frictional force between the protrusion 11 of the arm 10 and the spring plate 12. In this case, the larger the number of divisions, the smaller the torque per microstep, and several microsteps are required to overcome the frictional force between the protrusion 11 of the arm 10 and the spring plate 12 and rotate the lead screw 14. This is for the purpose of

For this reason, it is difficult to achieve a high track density by causing a stepping motor to operate in mask steps using a conventional head feeding mechanism, and even in a head feeding mechanism that does not utilize the track servo technology described above, the hysteresis characteristic described above Therefore, it is common practice to feed one track in two steps to improve track positioning accuracy.

An object of the present invention is to significantly reduce the frictional force between the carriage and the lead screw when the head-mounted carriage seeks in the radial direction of the surface of the disc-shaped information recording medium, and to further reduce the frictional force between the carriage and the lead screw during reciprocating movement of the carriage. It is an object of the present invention to provide an improved head feeding mechanism for an information recording/reproducing device that can significantly reduce hysteresis characteristics and improve the positioning accuracy of the carriage.

[Means to solve the problem]

The said purpose is a carriage with a fixed head.

In an information recording and reproducing device that includes a lead screw that guides the carriage in the radial direction of the disc-shaped information recording medium by rotation of a drive device, a rolling bearing is mounted on the carriage that is guided in the radial direction of the disc-shaped information recording medium by the lead screw. This is accomplished by attaching a rolling bearing and engaging the lead screw with the rotating body of the rolling bearing.

[Effect]

Therefore, as described above, the present invention provides a method in which a rolling bearing is mounted on a carriage guided in the radial direction of a disc-shaped information recording medium by a lead screw, and the lead screw is engaged with a rotating body of the rolling bearing. By this,
When the head-mounted carriage seeks in the radial direction of the information recording medium surface, the rolling bearing on the carriage side also rotates as the lead screw rotates, so the frictional force between the carriage and the lead screw is made so small that it can be ignored. Therefore, the hysteresis characteristic during the reciprocating movement of the carriage can be significantly reduced compared to the conventional method.

〔Example〕

The present invention will be explained below based on the drawings. Figures 1 and 2 show an embodiment of the present invention, and Figure 1(a)
1(b) is an enlarged vertical cross-sectional view showing the engagement portion between the rolling bearing 100 and the lead screw 14 attached to the head mounting carriage indicated by reference numeral 2 in FIG. 6, and FIG. ), FIG. 1(c) is a bottom view of FIG. 1(a), and FIG. 2 is a perspective view showing the connection between the carriage arm 19 equipped with a rolling bearing shown in FIG. 1 and the lead screw 14. It is.

Moreover, FIG. 3 shows the embodiment of the present invention shown in FIG. 2, and the same figure is a longitudinal cross-sectional view of the engagement portion between the rolling bearing 100 and the lead screw 14 corresponding to FIG. FIG. 5 is a vertical sectional view of a rolling bearing 100 showing a third and fourth embodiment of the present invention, respectively.

In FIG. 1, a protrusion 16 is formed on the circumference of the inner diameter of the inner ring 15 of the rolling bearing 100 to connect with the lead screw 14, and the inner ring 15 has balls 17
The inner ring 15 is attached to the outer ring 18 via
Rotates freely against. The protrusion 16 of the inner ring 15 engages with the groove of the lead screw 14, and the lead screw 1
4 rotates, the inner ring 15 also rotates at the same time, and the outer ring 18 is attached to a carriage arm (see reference numeral 19 in FIG. 2).

To attach the rolling bearing 100 to the carriage, the second
As shown in the figure, a hole for press-fitting or gluing the rolling bearing 100 is provided in the side surface of the carriage arm 19 integrally formed with the carriage, and the rolling bearing 100 is attached to the hole, and the rolling bearing 100 is installed in the hole. The carriage and lead screw 14 are engaged.

As described above, the present invention has the rolling bearing 100 mounted on the carriage that is guided in the radial direction of the disc-shaped information recording medium by the lead screw 14, and the rotating body of the rolling bearing 100 (the embodiment shown in FIG. 1). In the case of the example, inner ring 15
), when the head-mounted carriage is sought in the radial direction of the information recording medium surface, the rolling bearing 100 on the carriage side also rotates as the lead screw 14 rotates. The frictional force between the lead screw 14 and the lead screw 14 can be reduced to a negligible level, the hysteresis characteristic during reciprocal movement of the carriage can be significantly reduced compared to the conventional one, and the positioning accuracy of the carriage can be improved. As a result, the stepping motor 13 can be operated in microsteps, and high track density can be achieved using track servo technology. Further, the present invention can improve track positioning accuracy in the same manner as described above even in a head feeding mechanism that does not utilize track servo technology.

Further, the present invention presses the rolling bearing 100 in a direction perpendicular to the axis of the lead screw 14, that is, in FIG.
) By applying a load to the rolling bearing 100 from the direction of arrow A, the connection between the lead screw 14 and the protrusion 16 is ensured.

Radial runout of the rolling bearing 100 can be reduced.

Furthermore, the present invention can reduce the gap between the balls 17 and the inner ring 15 by applying a load to the rolling bearing 100 in the thrust direction of the rolling bearing 100, that is, from the direction of arrow B in FIG. 1(a). It is possible to reduce the gap between the ball 17 and the outer ring 18, thereby reducing radial runout and axial runout caused by the large gap, and further improve track positioning accuracy. .

Furthermore, the present invention can be implemented by mounting the inner ring of the rolling bearing 100 on the carriage and engaging the outer ring 18 of the rolling bearing 100 with the lead screw 14 as shown in FIG. Similarly, the frictional force between the carriage and the lead screw 14 can be made negligibly small.

In addition, as shown in FIGS. 1 and 2, the rolling bearing 1
When the inner ring 15 of 00 is engaged with the lead screw 14, the lead screw 14 is positioned within the rolling bearing 100.
fft L, the engagement between the lead screw 14 and the rolling bearing 100 becomes reliable, and the positioning accuracy of the carriage can be further improved. However, according to the configuration shown in FIG. 1, as described above, Since the engagement portion between the lead screw 14 and the rolling bearing 100 is located inside the rolling bearing 100, machining of the engagement portion of the rolling bearing 100 becomes somewhat difficult. On the other hand, when the outer ring 18 of the rolling bearing 100 is engaged with the lead screw 14, as shown in FIG. Therefore, the meshing portion of the rolling bearing 100 can be easily machined.

Next, as shown in FIG. 4, the present invention provides a rolling bearing 10.
By making 0 an angular rolling bearing, the inner ring 15
When applying a load in the thrust direction between the inner ring 15 and the outer ring 18, it is no longer necessary to provide four parts on the circumference of the inner ring 15 and the outer ring 18, and the inner ring 15 and the outer ring 18 can be manufactured by inexpensive synthetic resin molding. In addition, since the angular rolling bearing has only one surface in contact with the balls 17, its machining is easy. Furthermore, the present invention has the advantage that the mounting position accuracy of the rolling bearing 100 can be improved by integrally molding the outer ring 18 of the angular contact rolling bearing 100 with the synthetic resin material that constitutes the carriage, as shown in FIG. Combined. As shown in FIG. 5, if a rolling bearing 100 is used in which the inner ring 15 and the outer ring 18 are aligned in the thrust direction, there is no need to apply a load to the inner ring 15 and the outer ring 18 from the thrust direction. The structure of the entire device can be simplified.

Furthermore, as shown in FIG. 1, the outer ring 18 of the rolling bearing 100 is outsert-molded using a synthetic resin material constituting the carriage, thereby improving the mounting position accuracy of the rolling bearing 100, similar to the angular contact rolling bearing. can be improved.

〔Effect of the invention〕

The present invention is as described above, and as is clear from the description of the illustrated embodiments, according to the present invention, a rolling bearing is mounted on a carriage guided in the radial direction of a cylindrical information recording medium by a lead screw, By engaging the lead screw with the rotating part of this rolling bearing, when the head-mounted carriage is sought in the radial direction of the information recording medium surface, the rolling bearing on the carriage side also rotates as the lead screw rotates. Therefore, the frictional force between the carriage and the lead screw can be reduced to a negligible level, and the hysteresis characteristic during reciprocating carriage movement can be significantly reduced compared to the conventional method, thereby improving the positioning accuracy of the carriage. It is possible to provide an improved head feeding mechanism for an information recording/reproducing device that can perform the following functions.

[Brief explanation of the drawing]

1 and 2 show one embodiment of the present invention, and FIG. 1(a) shows a rolling bearing 100 and a lead screw 1 mounted on a head mounting carriage shown by reference numeral 2 in FIG. 6, which will be described later.
1(b) is a side view of FIG. 1(a), FIG. 1(,) is a bottom view of FIG. 1(a), and FIG. 2 is a perspective view showing the connection between the carriage arm 19 equipped with a rolling bearing shown in FIG. 1 and the lead screw 14, and FIG. 3 shows the embodiment of the present invention shown in FIG.
This figure is a longitudinal sectional view of the engagement portion between the rolling bearing 100 and the lead screw 14, which corresponds to FIG. 1(a), and FIGS. 4 and 5 show third and fourth embodiments of the present invention, respectively. A vertical cross-sectional view of the rolling bearing 100, FIG. 6 is a perspective view showing a conventional example of a head feeding mechanism for an information recording/reproducing device, and FIG. FIG. 3 is a reciprocating distance hysteresis characteristic diagram. DESCRIPTION OF SYMBOLS 1...Lower head, 2...Carriage, 3...Upper head, 4...Arm, 5...Spring plate, 6...
First guide shaft, 7 and 8...Guide hole, 9...
...Second guide shaft, 13...Stepping motor, 14...Lead screw, 100...Rolling bearing, 15...Inner ring, 16...Protrusion, 17...
Ball, 18...outer axis, 19...arm.

Claims (1)

[Claims] 1. In an information recording/reproducing device comprising a carriage with a fixed head and a lead screw that guides the carriage in the radial direction of a disc-shaped information recording medium by rotation of a drive device, Accordingly, a head feeder for an information recording/reproducing device is characterized in that a rolling bearing is mounted on a carriage that guides a disc-shaped information recording medium in the radial direction, and the lead screw is engaged with a rotating body of the rolling bearing. mechanism. 2. In the invention described in claim 1, the rolling bearing mounted on the carriage is a cylindrical rolling bearing,
A head feeding mechanism for an information recording/reproducing device, in which an outer ring of the cylindrical rolling bearing is mounted on a carriage, and an inner ring of the cylindrical rolling bearing is engaged with a lead screw. 3. In the invention set forth in claim 1, the rolling bearing mounted on the carriage is a cylindrical rolling bearing, the inner ring of this cylindrical rolling bearing is mounted on the carriage, and the outer ring of the cylindrical rolling bearing is a lead. A head feeding mechanism of an information recording/reproducing device that engages with a screw. 4. A head feeding mechanism for an information recording/reproducing apparatus according to the invention as set forth in claim 2 or 3, in which a rolling bearing mounted on the carriage is pressed in a direction perpendicular to the axis of the lead screw. 5. In the invention according to any one of claims 2 to 4, a head feeding mechanism for an information recording/reproducing device in which a load is applied in the thrust direction of a rolling bearing mounted on a carriage. 6. In the invention as set forth in claim 5, the head feeding mechanism of the information recording/reproducing device, wherein the rolling bearing mounted on the carriage is an angular rolling bearing. 7. In the invention according to any one of claims 1 or 3 to 5, the outer ring of the rolling bearing mounted on the carriage is outsert by a synthetic resin material constituting the carriage. Head feeding mechanism of a molded information recording and reproducing device. 8. A head feeding mechanism for an information recording/reproducing device according to the invention as set forth in claim 6, wherein the outer ring of the angular roller bearing is integrally molded from a synthetic resin material constituting the carriage.