JPS6018618A - Guide device for sliding body - Google Patents

Abstract

PURPOSE:To make both of fine feed from a stationary state in a sliding body and its accurate positioning control performable in an easy manner, by inserting a bearing installed in the sliding body into a guide shaft being driven for rotation all the time, while guiding and sliding the sliding body with this guide shaft. CONSTITUTION:A head transfer block 10 forming part of a linear motor is constituted of a bobbin 11 at the central part, a head supporting part 12 in the front part and a bearing part 13 in the rear. And, a guide shaft 18 is inserted into a couple of bearings 16a and 16b installed in the bearing part 13, while the head transfer block 10 is made to be free of reciprocating motion under guidance of this guide shaft 18 which is supported rotatably and slidably in an axial direction by bearings 20a and 20b installed in a pair of supporting parts 19a and 19b being solidly formed together with a chassis 2 and furthermore driven for rotation all the time by a pulley 21 and a belt 25 installed in a pulley 24 of a driving shaft 5 for a motor 3 and the guide shaft 18, respectively.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is most suitable for application to, for example, a magnetic head feeder of a magnetic disk recording/reproducing device, an optical head feeder of an optical disk device, etc. In particular, the present invention relates to a guide device for a sliding body that requires fine feeding and accurate position control.

[Background technology and its problems]

BACKGROUND OF THE INVENTION There are sliding bodies that require minute movement and accurate position control in various devices, such as magnetic head movement in magnetic disk recording and reproducing devices and optical head movement in optical disk devices. Conventionally, as a guide device for these sliding bodies, a method has been adopted in which the sliding body is guided by a guide shaft provided in the sliding direction. However, since this guide shaft is fixed, there is a problem in that the frictional resistance is large when the sliding body is made to slide, and a large force is required to drive the sliding body. Furthermore, when controlling the position of a sliding body by minutely moving it from a stationary state, there is also the problem that position servo is difficult to apply due to a nonlinear change in frictional resistance, that is, a sudden change from static frictional resistance to dynamic frictional resistance. In order to make the sliding body slide from a stationary state, a driving force exceeding the static frictional resistance is applied, but once the sliding body begins to slide, it becomes dynamic frictional resistance and the frictional resistance is drastically reduced. Therefore, if the driving force is applied as it is, the sliding body will slide excessively, so it is necessary to apply rapid servo to weaken the driving force. However, such a servo cannot follow position control unless it has a large dynamic range and high responsiveness. For this reason, it has been extremely difficult to move the sliding member minutely from a stationary state and to control its position accurately.

[Purpose of the invention]

The present invention aims to provide a guide device for a sliding body that can solve the above-mentioned problems.

[Summary of the invention]

The present invention is configured such that a bearing provided on a sliding body is inserted into a guide shaft, and the sliding body is guided and slid by the guide shaft while the guide shaft is constantly driven by a motor for 5 rotations. In this sliding body guide device, the frictional resistance between the bearing and the guide shaft is drastically reduced, and the driving force for sliding the sliding body is extremely small. In addition, there is no non-linear change in frictional resistance when the sliding body is moved from a stationary state.
The position servo of the sliding body becomes extremely easy to apply. Therefore, minute feeding of the sliding body from a stationary state and accurate position control of the sliding body can be performed extremely easily.

〔Example〕

An embodiment in which the present invention is applied to a magnetic disk recording/reproducing device will be described below with reference to the drawings.

First, as shown in FIGS. 411 to 6, a motor (3) is provided on a chassis (2) of a main body (1) of a magnetic disk recording and reproducing apparatus. This motor (3) directly moves a magnetic disk (4) indicated by a phantom line in FIG. 1, and has a rotary table (6) fixed to its drive shaft (5). Note that (7) and (8) are a rotational drive pin and a ring-shaped magnet, respectively, provided on the rotating table (6).

Next, the chassis (2) is provided with a head moving table aω. As shown in FIG.
and a rear bearing part (13).

The bobbin (11) has a hollow flat shape, and a coil α is formed on the outer periphery. Also, the head support part (
A magnetic head (19) is fixedly installed in I''IJ.Furthermore, a pair of bearings (16a) (16b) are provided in the bearing portion a moat.These bearings (16a) (16
For b), metal bearings or oil-impregnated bearings are used.

Then, the head support part α and the bearing part Q31 are connected to the bobbin (1
It is fixed to the left and right flanges (11a) and (11b) of 1) with screws or the like. And the head moving table (10
) is a bearing (ISa) as shown in Figures 1 and 2.
The magnetic head (19) is guided by a guide shaft (+8) inserted through the (ISb) to be able to reciprocate freely, and accordingly, the magnetic head (19) is reciprocated in the radial direction of the drive shaft (5) of the motor (3). It is configured as follows.

Note that this head moving table FIO) is the sliding body referred to in the present invention.

Next, as shown in detail in FIGS. 1, 2, and 5, the guide shaft 08 is mounted on a bearing ( 20a) (20b) is rotatable around its axis and supported slidably in its axial direction. Note that metal bearings or the like are used for these bearings (20a) (20b). A first pulley (2υ) is fixed to one end (1aa) of the guide shaft (18), and a first pulley (2υ) is fixed to one end (1aa) of the guide shaft (18).
13b) is processed into a spherical shape and abuts against a thrust receiver (23) screwed into a support portion (221) formed integrally with the chassis (2).

Thus, the guide shaft a8 is configured to be constantly rotationally driven by the motor (3). That is, as shown in FIGS. 1 to 6, a second boolean IJ (24) is fixed to the drive shaft (5) of the motor (3) at a lower position of the rotary table (6). Note that the guide axis (country and motor (3) 1 view axis (
5) are arranged at twisted positions substantially perpendicular to each other.

And the guide shaft (the country's first pulley (2υ) and the drive shaft (5)
27'-IJ C24) is wrapped with a belt (2 belts) made of an elastic square belt.

By the way, this belt (the two are shown in Figure 5,
Pulley (winding side from 2nd to 1st boo 1υ (25a)
is perpendicular to the axial direction of the guide shaft (1 barrel), and the unwinding side (2
5b) is inclined at a predetermined angle θ with respect to the axial direction of the guide shaft 08.

Note that the unwinding side (25b) is wound around the second pulley (24) at right angles to the axial direction of the drive shaft (5).

Next, as shown in FIGS. 2 and 6, the head moving table (+1) constitutes a part of a linear motor, and the head moving table (1) is reciprocated by this linear motor.

In other words, there are six flat yokes C on the chassis (2)! 7)
@ (21 is a pair of magnets (30a) between each
(30b), (31a) and (31b) are placed in between. And the head movement gold times is coil 0 (a)
Each yoke (2η(2
) and G! 81 (It is configured to reciprocate between two scratches. Note that the head support part (1) of the head moving table θ0)
The shaft is supported from below by a movable steel ball 0 within a groove C32 provided in the chassis (2). Then, move the head 1iJJ stand (1 (It is a guide shaft (1) and a steel ball (by bleaching,
2) is reciprocated in a parallel state.

According to the magnetic disk recording and reproducing apparatus configured as described above, first, the motor (3) is rotated in the direction of arrow a in FIG. 1, and the magnetic disk (4) is rotationally driven. The current flowing through the coil (141) formed in the bobbin 01 of the head moving table (10) causes the head moving table (10) to
) is reciprocated and desired recording or reproduction is performed by the magnetic head (151).

Thus, when motor (3) is rotated, bell) <25
), the guide shaft (one barrel is rotated at high speed.) By rotating the guide shaft 08 at high speed, the head moving table (
IO1O bearing (16a) (16b) and guide shaft θ8)
The frictional resistance between the two is extremely small. That is, when the guide shaft decoy is rotated at high speed, the bearings (16a) (16b
), if a metal bearing is used, the bearing (16a)
Negative pressure is generated between the inner circumferential surface of (16b) and the guide shaft α, and an air film is formed. Also bearing (16a)
When an oil-impregnated bearing is used for (16b), the oil impregnated in the oil-impregnated bearing oozes out due to the same negative pressure as described above, and an oil film is formed. As a result, the bearings (16a) and (16b) are lifted from the guide shaft θ mallet, and the bearings (16a and 16b) are lifted up from the guide shaft θ mallet.
a) The frictional resistance between (16b) and the guide shaft (I8) will be drastically reduced. For this reason, the head moving table aCj
The driving force required for sliding is extremely small. Furthermore, since the bearings (16a) (ISb) and the guide shaft 0 are always in a state of dynamic frictional resistance, there is no non-linear change in the frictional resistance when the head moving table OI is slid. That is, since there is no sudden change from static frictional resistance to dynamic frictional resistance when the head moving table (It) is slid from a stationary state, position servo of the head moving table αQ is extremely easy to apply. Therefore, minute movement of the head moving table (II) from a stationary state and precise position control can be performed extremely easily.

Next, by rotating the guide shaft α second, the guide shaft (I mark is always axially in one direction, the arrow mark direction in FIG. 5) is thrust-energized. That is, the second pulley (24) d (bell to 1st boo IJ 0υ) (25) winding side (2
5a) at right angles to the axial direction of the guide shaft (1 mark),
1st).

-Second goo from Ri (21)! j bell to (24))(
The unwinding side (25b) of 2SI is inclined at a predetermined angle θ with respect to the axial direction of the guide shaft QFj. Therefore, a biting action occurs in the direction in which the rotating part (25) is tilted (the rotating part varies depending on the pulley diameter, inclination angle, etc.). Then, as shown in Fig. 5, the belt (unwinding side (25b) of 29)
The tensile force P of
1 is always thrust in one axial direction, that is, in the direction indicated by the arrow. If this thrust force remains constant as the guide shaft O1 rotates, it is possible to extremely stably thrust the guide shaft O barrel toward the thrust receiver 4 side. Additionally, since no special parts are required for the thrust energizer, assembly is easy due to a reduction in the number of parts, and there is no need for any troublesome adjustments.

Note that the guide shaft referred to in the present invention can be rotated in a forward or reverse direction regardless of the direction of rotation thereof, and various methods other than those shown in the embodiments can be applied to drive the guide shaft to rotate with a motor. Furthermore, the number of guide shafts is not limited to one, but it is also possible to use a plurality of guide shafts.

[Application example]

Although one embodiment of the present invention has been described above, the present invention is not limited to the magnetic disk recording/reproducing device shown in the embodiment, but can also be applied to head feed of an optical disk device, arm feed of a linear tracking player, typewriter, etc. - It can be applied to carriage feeds in XY plotters, pen feeders in XY plotters, and guide devices for sliding bodies in other types of equipment.

[Effects of the Invention] As described above, the present invention allows the bearing provided on the sliding body to be inserted into the guide shaft, and the sliding body to be guided by the guide shaft while the guide shaft is constantly rotationally driven by a motor. This is a guide device for a sliding body that is configured so that it can be slid. According to the present invention, the frictional resistance between the bearing of the active body and the guide shaft is drastically reduced, and the driving force for sliding the sliding body can be extremely small. Furthermore, nonlinear changes in frictional resistance when the sliding body is caused to slide from a stationary state are eliminated, making it extremely easy to apply position servo to the sliding body. Therefore, micro-feeding of the sliding body from a stationary state and accurate position control can be performed extremely easily.

[Brief explanation of the drawing]

The drawings show an embodiment in which the present invention is applied to a magnetic disk recording/reproducing device, in which FIG. 1 is a plan view of the main body of the device, FIG. 2 is a perspective view of the main parts, and FIG. Figure 4 is an exploded perspective view of the head moving table, Figure 5 is an enlarged plan view showing the guide shaft and its related parts in cross section, and Figure 6 is FIG. 2 is an enlarged sectional view taken along the line -Vl in the figure. In addition, in the symbols used in the drawings, (3)...Motor OQ...
・・・・・・Head moving table (16a) which is a sliding body (
16b) -Bearing (18)......It is a guide shaft. Agent Masaru Ueya Yoshio Tsuneko Toshiki Sugiura

Claims (1)

[Claims] A guide for a sliding body, in which a bearing provided on the sliding body is inserted into a guide shaft, and the sliding body is guided and slid by the guide shaft while the guide shaft is constantly rotationally driven by a motor. Device.