JPH039188Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a head transport mechanism in a magnetic disk drive device, and in particular, a head carriage equipped with a magnetic head is moved by a step motor driven by a magnetic disk carried on a spindle. The present invention relates to a head feeding mechanism in a magnetic disk drive device that moves a disk along the radial direction.

[Prior art]

Generally, this type of magnetic disk drive is provided with one spring that biases the head carriage in one direction of movement. However,
As the entire magnetic disk drive device became smaller, the tension springs were also forced to be smaller and shorter.
The tensile force of one spring is insufficient, so two
You may want to set up a book. However, if the two spring forces are set equally, it is impossible to predict which direction the spring force will lean in the direction of movement of the head carriage due to variations in the intersection of each component that are unavoidable in manufacturing, resulting in extremely unstable conditions. becomes. Therefore, a guide shaft movably guides the head carriage;
There is always a gap between the magnetic head and the head carriage, so in conventional models, if this gap is large, the magnetic head may meander from side to side when moving, which degrades track positioning reliability. Ta. Furthermore, if the magnetic disk is installed in a vertical orientation, even if the magnetic head is properly installed horizontally, the weight of the head carriage will cause the magnetic head to shift its position. Ta.

[Purpose of invention]

This invention eliminates the drawbacks of the conventional ones as described above, and has a configuration suitable for miniaturization with two springs, and a structure that is suitable for miniaturization. To provide a head feeding mechanism in a magnetic disk drive device which prevents a magnetic head from meandering left and right when moving even if there is a certain gap, and which can be used even in a vertical position.

[Summary of the idea]

This invention provides a magnetic disk drive device in which a head carriage on which a magnetic head is mounted is moved along the radial direction of a magnetic disk supported on a spindle by driving a step motor. 2. A cam follower provided on the head carriage is brought into contact with a cam rotated by the step motor by biasing the cam follower in one of the directions.
The general idea is that two springs are provided and the biasing forces of the springs are made to be different from each other so that the head carriage is always pressed in one direction against the guide shaft.

[Example of idea]

Embodiments of this invention shown in the drawings will be described below.

The drawing shows a head feeding mechanism in a magnetic disk drive device according to this invention, and this magnetic disk drive device moves a magnetic head 2 along the radial direction of a magnetic disk (for example, a floppy disk) (not shown) supported on a spindle 1. A head carriage 3 carrying the magnetic head 2 is provided movably along guide shafts 4A and 4B extending parallel to the locus of movement of the magnetic head 2 on both sides of the locus of movement of the magnetic head 2. The vertical direction of the head carriage 3 is connected to the head carriage 3, and the guide shaft 4B
is inserted into the head carriage 3 so that the head carriage 3 is restricted in the vertical and horizontal directions (see FIGS. 2a and 2b). Note that a certain amount of clearance exists between the guide shafts 4A, 4B and the head carriage 3.

Furthermore, one ends of springs 5A, 5B are connected to the head carriage 3 on the outside of the guide shafts 4A, 4B, and the other ends of the springs 5A, 5B are connected to a frame (not shown).
The head carriage 3 is biased in the direction away from the spindle 1 along the radial direction of the spindle 1 (that is, the magnetic disk) by the tensile forces of A and 5B, and by using two springs 5A and 5B. In addition to providing sufficient spring force comparable to using one large spring, the length of the spring can be shortened to contribute to miniaturization. Further, the biasing force (tensile force) of the spring 5A is greater than the biasing force (tensile force) of the spring 5B, so that the head carriage 3 is always slightly tilted in one direction in proportion to the gap with the guide shaft. .

Further, a cam follower 6 is provided upright in the head carriage 3 in a plane that passes through the axis of the guide shaft 4B and is perpendicular to the magnetic disk carried on the spindle 1.

and comes into contact with the side surface of the cam follower 6,
A cam 7 that drives the cam follower 6 is rotatably provided in the plane about an axis perpendicular to the magnetic disk, and a large-diameter gear 8 is mounted on the cam 7 to rotate integrally with the cam 7. This gear 8 is attached to a small diameter gear 1 integrally attached to the rotating shaft of a step motor 9.
It meshes with 0.

The shape of the cam 7 is such that when the cam 7 is rotated by a predetermined angle by the step motor 9, the cam follower 6
The head carriage 3 is configured to be moved by a fixed amount via the head carriage 3.

Next, the operation of the above will be explained.

When the step motor 9, which is the driving source, is driven, the cam 7 rotates by a predetermined angle via the gears 10 and 8, and the head carriage 3 is thereby moved by a predetermined amount via the cam follower 6.

At this time, the head carriage 3
Due to the difference between the large biasing force of the spring 5A and the smaller biasing force of the spring 5B, it is always tilted in one direction even when stationary or when moving. On the other hand, the magnetic head does not wobble from side to side, and therefore moves stably. Further, as described above, even when used in a vertical position, the head carriage 3 is always pressed in a fixed direction against its weight.

[Effect of idea]

By configuring this idea as described above,
In a configuration suitable for miniaturization using two springs, a certain amount of clearance is created between the head carriage and the guide shaft due to the extremely simple structure in which the biasing forces of the two springs are different from each other. However, the head carriage is always pressed against one side of the guide shaft. Therefore, it is possible to prevent the magnetic head from meandering left and right when moving, improving track positioning accuracy, and
It has excellent effects such as being able to be used stably even in a vertical position.

[Brief explanation of the drawing]

FIG. 1 is a schematic layout diagram showing an embodiment of this invention, and FIGS. 2a and 2b are explanatory diagrams showing the relationship between the guide shaft and the head carriage. 1...Spindle, 2...Magnetic head, 3...
Head carriage, 4A, 4B...Guide shaft, 5A, 5B...Spring, 6...Cam follower,
7...Cam, 8, 10...Gear, 9...Step motor.

Claims (1)

[Scope of utility model registration request] In a magnetic disk drive device, a head carriage equipped with a magnetic head is moved along the radial direction of a magnetic disk supported on a spindle by driving a step motor. The present invention is characterized in that two springs are provided which are biased towards each other to bring a cam follower provided on the head carriage into contact with the cam rotated by the step motor, and the biasing forces of these springs are made different from each other. head movement mechanism in a magnetic disk drive device.