JP2524057B2 - Carriage transfer device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floppy disk device used as a data storage device for computers, word processors and the like, and more particularly to a carriage transfer device for transferring a magnetic head to a desired position.

[0002]

2. Description of the Related Art In recent years, a floppy disk device has been mounted on a personal computer or a word processor that is easy to carry, and there is an increasing demand for a small size, light weight, and low power consumption of the floppy disk device. For this reason, the carriage transfer device is also required to have a smaller size and lower power consumption.

4 to 8 show a general example of a carriage transfer device of a conventional floppy disk device.

Reference numeral 1 denotes a flexible magnetic disk, a so-called floppy disk, which is mounted on a rotary drive shaft 2 by a mounting means (not shown) and rotationally driven by a motor 3. 4 is the recording of information on the floppy disk 1,
It is a magnetic head for reproducing and is mounted on the head carriage 5. Reference numeral 6 denotes a head pad, which is provided at the tip of the pad arm 7 so as to face the magnetic head 4. The rear end of the pad arm 7 is rotatably supported near the rear end of the head carriage 5. . During operation, the head pad 6 is urged toward the magnetic head 4 by the elastic force of the pad arm spring, and the floppy disk 1
It will be in the state of sandwiching. Reference numeral 9 is a stepping motor, the rotation shaft of which is a lead screw 10 in which predetermined leads are cut. The lead screw 10 is
The needle 11 fixed to the head carriage 5 and the leaf spring 12 sandwich the groove 10a of the lead screw 10.
The needle 11 is engaged with.

FIG. 6 and FIG. 7 are views showing the engaged state of the lead screw 10 and the needle 11.

The protrusion 5a of the head carriage 5 has a V
There are grooves 5b and 5c having a rectangular cross section, and the needle 11 is positioned while being supported at both ends by the grooves 5b and 5c, and is fixed by the pressing plate 14. The pressing plate 14 is
It is joined together with the leaf spring 12 by a set screw 15 via a collar 16. The leaf spring 12 generates an elastic biasing force in the direction of pushing the lead screw 10 toward the needle 11 at the point of contact with the lead screw 10. As a result, the elastic urging force urges the protrusion 5a of the head carriage 5 in the direction of the arrow H, and the needle 1
No. 1 is always engaged with the groove portion 10a of the lead screw 10 without rattling.

Reference numeral 13 is a guide rod which is arranged substantially parallel to the lead screw 10 and whose both ends are fixed to the base body 17. The guide rod 13 penetrates the head carriage 5, and the sleeve 1 provided on the head carriage 5
It is supported by 8 and 19. In FIG. 8, the sleeves 18 and 19 are arranged at both ends of a hole 5d penetrating the head carriage 5 in the longitudinal direction, and generally a sintered oil-impregnated metal or a resin having good slidability is press-fitted or bonded. Fixed. The head carriage 5 is the guide rod 1 described above.
It is possible to reciprocate in the radial direction of the floppy disk 1 by being guided by 3.

In the carriage transfer device having the above structure,
When a predetermined drive current is intermittently supplied to the stepping motor 9 from a drive circuit (not shown), the lead screw 10 correspondingly rotates intermittently by a predetermined rotation angle. As the lead screw 10 rotates, the groove 10
The needle 11 engaged with a is fed in the axial direction of the lead screw 10 and thus the head carriage 5
Is guided by the guide rod 13 and the floppy disk 1
Intermittently moving in the radial direction (for example, Japanese Patent Laid-Open No. 57-36473).

[0009]

However, in such a structure, the guide rod 13 and the sleeves 18 and 1 are provided.
There is always a gap between 9 and. Therefore, the driving point of the head carriage 5, that is, the distance from the engaging portion of the lead screw 10 and the needle 11 in the conventional example to the guide rod 13 is multiplied by the thrust force applied to the needle 11 by the lead screw 10. When a moment is generated, the head carriage 5 tilts in the acting direction of the moment by the clearance. As a result, the magnetic head 4 also moves in the radial direction of the floppy disk 1 and is displaced with respect to a predetermined position. Further, the above deviation is magnified by the moving direction of the head carriage 5. That is, in contrast to the displacement generated when the head carriage 5 moves in the inner peripheral direction of the floppy disk 1, when the head carriage 5 moves in the outer peripheral direction, a reverse moment is applied to the head carriage 5, so that the displacement direction is opposite. become. Therefore, even when they are positioned at the same position, the above two deviations are summed up when moving in the inner circumferential direction and when moving in the outer circumferential direction.

Also, due to the action of the moment, there is a case where a prying occurs between the guide rod 13 and the sleeves 18 and 19, and in order to avoid this, it is necessary to increase the distance between the sleeve 18 and the sleeve 19. For this reason, the head carriage 5 becomes long in the moving direction, and the configuration of the entire apparatus is also limited.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and the head carriage is moved.
Engage the lead screw at one end in the direction of motion
And an engaging member that engages
From the direction substantially perpendicular to the
A first support portion slidably abutting on the head,
On the other end in the moving direction of the carriage, the above-mentioned engagement
The lead from the same direction as the member and the first support portion.
Approximately slidably abut each other on the outer circumference of the screw.
Angled second and third support portions are provided, and further,
The engaging member engages with the lead screw, and
The first, second and third support parts are the outer circumference of the lead screw.
The head carriage so that they come into contact with the respective parts.
An elastic biasing means for elastically biasing is provided, and the head carriage is
Is driven by the driving force given by the lead screw.
By using the above lead screw as a guide,
It is characterized in that it is configured to move in a determined direction .

[0012]

The following actions are obtained by the above means.

The lead screw abuts two or more wall surfaces and is elastically biased so that rattling does not occur. That is, the head carriage is supported by the lead screw without rattling while sandwiching the lead screw by two or more wall surfaces. Further, since the lead screw itself is transferred as a guide, no moment is generated in the head carriage. Therefore, when the head carriage moves, the head carriage does not tilt and the magnetic head is positioned at a predetermined position. Moreover, since no moment is generated in the head carriage, no prying occurs.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 20 is a spindle motor fixed to a base body 21, and its rotation is transmitted to a spindle pulley 24 fixed to one end of a spindle 23 via a transmission belt 22. A magnetic head 25 is mounted on the upper part of the head carriage 26 (on the back side of the head carriage 26 in FIG. 1). Reference numeral 27 is a stepping motor, the rotation shaft of which is a lead screw 28 in which predetermined leads are cut.

The head carriage 26 has a shape in which one end thereof is bent into an L shape. In the vicinity of both ends in the longitudinal direction of the bent portion 26a, support portions 29, 30 which are somewhat protruded from other portions are formed.

The support portion 29 is formed only on the inner side surface of the bent portion 26a. On the other hand, the support portion 30 includes the bent portion 26a.
A portion 30b formed on the inner surface of the head carriage 26 and a portion 30a formed on the back surface of the head carriage 26 and forming a substantially right angle with the support portion 30b (FIG. 3). The surfaces of the support portion 29 and the support portion 30b are arranged in such a positional relationship that they are included in the same plane. In addition, the surface of each support portion is smooth and is in a state of low friction.

Reference numeral 31 is a needle for engaging with the lead screw 28, and both ends thereof are supported and fixed by a support portion 29 and a projection portion 32 formed so as to face the support portion 29.

The head carriage 26 is supported in a state where all of the above-mentioned supporting portions are in contact with the outer peripheral portion of the lead screw 28 and the needle 31 is engaged with the lead screw 28. That is, the surfaces of the support portion 29 and the support portion 30b contact the outer peripheral portion of the lead screw 28 in the same direction, and the support portion 30a and the needle 31 contact in the substantially perpendicular direction. If more detail say, since each surface of the support portion 29 supporting portion 30b is a positional relationship contained in the same plane, the lead screw 28, identical of the mother line of an outer circumferential surface of the lead screw 28 The surfaces of the support portion 29 and the support portion 30b are in line contact with each other as one tangential line. Further, the needle 31 is shown in FIG.
In this case, since it is fixed in a posture substantially perpendicular to the surface of the support portion 29, the lead screw 28 is engaged in the same direction as the contact direction of the support portion 30a.

Assuming that a leaf spring is adopted as an example of the elastic biasing means, 33 is a leaf spring bent at the central portion, and one bent surface is set screws 34, 35 on the surface of the head carriage 26. It is fixed at. Leaf spring 33
The end of the free surface of is U-shaped, between which the roller 37 is arranged. Roller 37 has pin 3 at its center
The pin 36 is rotatably penetrated by 6, and both ends of the pin 36 are supported by the U-shaped portion of the leaf spring 33.

In the leaf spring 33, the lead screw 28 is arranged from the direction in which the roller 37 is located substantially at the center of the supporting portion 29 and the supporting portion 30 and forms an angle of about 45 ° with the surface of each supporting portion.
A predetermined elastic biasing force is applied to the lead screw 28 via the roller 37.
The elastic biasing force applied to the lead screw 28 is
It is divided into a component force that presses the lead screw 28 against the support part 29 and the support part 30b and a component force that presses against the support part 30a and the needle 31. As a result, each support portion maintains a loose contact state with the outer peripheral portion of the lead screw, and the needle 31 is always reliably engaged with the lead screw 28.

A long groove 38 is provided on the back surface of the end portion of the head carriage 26 opposite to the bent portion 26a.
The long groove 38 is elongated in the moving direction of the head carriage 26, and a steel ball 39 is movably arranged in the groove portion having a uniform depth. The steel ball 39 has the bottom surface 3 of the long groove 38.
8a and a sliding surface 21a which is a part of the base 21 and faces the long groove 38, and is sandwiched by the head carriage 26.
I support. The head carriage 26 faces the surface of the head carriage 26 on the side opposite to the long groove 38, and is projected from the base 21.
1b is protruding. The distance between the head carriage 26 and the protrusion 21b is sufficiently small so that the steel ball 39 does not fall out of the long groove 38 even if the head carriage 26 rattles.

As is clear from the above description, the posture of the head carriage 26 is determined and supported by the lead screw 28. Further, the leaf spring 33 is provided not only for securely engaging the needle 31 and the lead screw 28, but also for holding the head carriage 26 in a predetermined posture.

In the carriage transfer device having the above-described structure, when a predetermined drive current is intermittently supplied to the stepping motor 27 from a drive circuit (not shown), the lead screw 28 corresponds to the predetermined rotation angle. Rotate intermittently. As the lead screw 28 rotates, the needle 31 engaged with the lead screw 28 is sent in the axial direction of the lead screw 28, and the head carriage 26 is guided by the lead screw 28 and intermittently moves.

When the head carriage 26 is moved,
The respective support portions provided on the head carriage 26 are always kept in contact with the outer peripheral portion of the lead screw 28, or even if they are separated during the movement, when the head carriage 26 is stationary at a predetermined position, they are brought into contact with each other again. Return to the state. Needle 31 is always the lead screw 28
The engagement state is maintained, and the engagement does not come off even when the head carriage 26 is moving. Therefore, the head carriage 26, that is, the magnetic head 25 is positioned without shifting to a predetermined position.

The roller 37, which is pressed against the outer periphery of the lead screw 28 by the leaf spring 33, transmits its rotational force as the lead screw 28 rotates, and the body also rotates. Since the diameter of the roller 37 is sufficiently larger than the diameter of the pin 36 which is the rotation axis thereof, the frictional force generated between the roller 37 and the pin 36 is negligible. In addition, the roller 37 and the lead screw 2
The frictional force generated between 8 and 8 is rolling friction, and the coefficient of friction is extremely small. Therefore, in order to hold the head carriage 26 in a predetermined posture, and also to maintain the needle 3
Even if the elastic biasing force of the leaf spring 33 is increased in order to ensure the engagement between the first screw 1 and the lead screw 28, the load moment due to the frictional force applied to the lead screw 28 from the roller 37 does not become so large.

[0027]

As described above, according to the present invention, the head carriage can be supported without backlash, and an unnecessary moment is not generated in the head carriage. Therefore, the magnetic head is accurately positioned at a predetermined position. It Further, the distance between the supporting means of the head carriage, that is, the distance between the conventional sleeves can be made smaller than that of the conventional one because there is no concern about prying, and the size of the head carriage can be made smaller. Further, conventional guide rods, sleeves, and other parts are not required, and a simple and inexpensive carriage transfer device is realized.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, and is a partially cutaway plan view of a carriage transfer device incorporated in a base body of a floppy disk device as seen from the back side of the base body.

FIG. 2 shows an embodiment of the present invention and is a side view thereof.

FIG. 3 shows an embodiment of the present invention and is a view taken in the direction of arrow J of FIG.

FIG. 4 shows a conventional carriage transfer device,
The plan view

FIG. 5 shows a conventional carriage transfer device,
Same side view

FIG. 6 shows a conventional carriage transfer device,
Sectional view of a main part of a conventional carriage transfer device

FIG. 7 shows a conventional carriage transfer device,
Its side view

FIG. 8 shows a conventional carriage transfer device,
Partial cutaway plan view of conventional carriage

[Explanation of symbols]

 20 spindle motor 21 base 22 transmission belt 23 spindle 24 spindle pulley 25 magnetic head 26 head carriage 27 stepping motor 28 lead screw 29, 30 support portion 31 needle 33 leaf spring 37 roller

Claims (1)

(57) [Claims] With a 1. A lead screw, and a motor for rotationally driving this recording information, and a movable head carriage while mounting the reproducing means, the Heddokya
In the ridge, in the moving direction of the head carriage
An engaging portion that engages with the lead screw on one end
Material is provided and the direction in which this engaging member engages
And slide on the outer periphery of the lead screw from a direction almost perpendicular to
A first support portion that abuts as much as possible is provided, and the head key is
At the other end in the moving direction of the carriage, the engaging portion
From the same direction as the material and the first support portion.
Sliding abutments on the outer periphery of the crow, approximately right angles to each other
Second and third support portions that form the above-mentioned structure , and further, the engaging member engages with the lead screw, and
The first, second, and third supporting portions are the same as those of the lead screw.
Make sure that the head carriage is
A carriage for elastically urging the head carriage , wherein the head carriage moves in a direction determined by the lead screw while being guided by the propulsive force applied from the lead screw. Transfer device.