JPH087965B2 - Retraction mechanism of magnetic head in magnetic recording / reproducing apparatus - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to recording a signal on an arbitrary track by moving a magnetic head in a radial direction of a rotating magnetic recording medium, reproducing a signal from an arbitrary track, or The present invention relates to a magnetic head retracting mechanism that moves a magnetic head away from a magnetic recording medium at an arbitrary position of the magnetic head in a magnetic recording / reproducing apparatus that performs both recording and reproducing, that is, retracts the magnetic head.

2. Description of the Related Art Conventional Problems and Their Problems The electronic still camera (still video camera) that electronically shoots a subject and records the still image on a magnetic recording medium, and other magnetic recording devices and magnetic recording media. There are a magnetic reproducing device for reading out a still image signal and displaying it on a television, a magnetic recording / reproducing device having both recording and reproducing functions, and the like. In these devices, a rotating magnetic recording medium having multiple tracks (hereinafter referred to as a magnetic disk) is used, and a magnetic head records a still image signal on a predetermined track or a still image signal from a desired track. Playback is performed. The magnetic head is supported by a head carriage, and the magnetic head is moved in the radial direction of the magnetic disk together with the carriage to access a track to be recorded or reproduced.

To record a still image signal on a magnetic disk or to read a still image signal from a magnetic disk, the magnetic head is brought into close contact with the recording or reproducing surface (recording / reproducing surface) of the magnetic disk, and the magnetic head is pressed against the magnetic disk. The magnetic disk is attached so that it is partially deformed. A magnetic disk has some elasticity and has the property of returning to its original state even if it is slightly deformed.
There is no problem even if the magnetic head is pressed against the rotating magnetic disk during recording or reproduction. However,
If the magnetic head is applied to one place where the rotation of the magnetic disk is stopped, if this state continues for a long time (for example, several hours to several days), Deformation becomes permanent and the magnetic disk marks the magnetic head.

There are various techniques for preventing the adhesion of the trace of the magnetic head to the magnetic disk.
One of them is the idea of separating the magnetic head from the magnetic disk when recording or reproducing is not performed on the magnetic disk. It is common to move the magnetic head away from the magnetic disk while the magnetic disk remains fixed to the motor spindle, and this is called retraction of the magnetic head. In order to retract the magnetic head, it is necessary to retract the portion that supports the magnetic head, but since the magnetic head is transported in the radial direction of the magnetic disk together with the support portion as described above, the retract mechanism is complicated. There is a problem that it becomes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic head retracting mechanism having a relatively simple structure capable of retracting the magnetic head regardless of the position of the magnetic head on the magnetic disk.

This invention has a recording / reproducing magnetic head, and the recording / reproducing magnetic head is movably supported on a spindle so as to move in the radial direction of a magnetic disk. A head carriage that is tiltable about the support shaft, and the head carriage is moved in a direction in which the recording / reproducing magnetic head moves away from the magnetic disk when the recording / reproducing magnetic head is in contact with the magnetic disk. In a magnetic head retracting mechanism in a magnetic recording / reproducing apparatus including a mechanism for tilting about the support shaft, and a substrate on which the head carriage and the tilting mechanism are mounted, the support shaft is located near one end thereof. A lead screw having a threaded portion formed on its end, and the lead screw is rotated at its both ends by bearings provided on the substrate. The head carriage includes a horizontal sliding portion and a vertical sliding portion that are rotatably supported and are in a position near the other end of the lead screw and abut on portions other than the screw portion in directions substantially orthogonal to each other. A needle that fits in the groove of the thread portion of the lead screw is provided substantially horizontally on the head cage, and a protrusion that abuts the thread of the thread portion near the position of the needle. The sliding portion is formed substantially vertically on the head carriage, the horizontal sliding portion and the vertical sliding portion are on the peripheral surface near the other end of the reed screw, and the needle is on the reed screw. A first attachment for biasing the head carriage substantially horizontally and vertically in the groove of the screw portion so that the protruding sliding portion abuts on the thread of the screw portion, respectively. Mechanism is characterized in that provided on the substrate.

A second biasing mechanism that biases the lead screw in a direction opposite to the biasing direction of the first biasing mechanism is provided so as to balance with the biasing force of the first biasing mechanism. It is preferable.

In the above, the magnetic recording / reproducing apparatus includes a magnetic recording apparatus for recording information on a magnetic disk, a magnetic reproducing apparatus for reproducing information recorded on the magnetic disk, and recording of information on the magnetic disk and recording on the magnetic disk. This is a concept including a magnetic recording / reproducing device that performs both reproduction of existing information.

According to the present invention, the needle is inserted into the groove of the thread portion of the lead and the screw. The head carriage tilts with the groove surface of the threaded portion and the peripheral surface of the needle as contact points.

When the head carriage is tilted by the tilting mechanism, the magnetic head is retracted from the magnetic disk.

When the reed screw is rotated, the screw part is rotated, and the needle is guided and transferred in the axial direction of the reed screw. As a result, the head carriage is guided and transferred in the axial direction of the lead screw.

Therefore, the transfer of the head carriage, the close contact of the magnetic head to the magnetic disk, and the retraction of the magnetic head from the magnetic disk can be achieved.

In order to rotatably and slidably receive the reed screw, the needle is inserted into the groove of the screw part near one end of the reed screw in a substantially horizontal posture, and in the vicinity of this needle, it is almost perpendicular to the thread of the screw part. The protruding sliding part that is in contact with the lead screw, and the horizontal sliding part and the vertical sliding part that are almost horizontally and vertically contacted with the peripheral surface of the lead screw near the other end part where the screw part of the lead screw is not provided. It is provided on the carriage. These needle and lead screw thread groove, protruding sliding portion and screw thread, and horizontal and vertical sliding portion and lead screw peripheral surface abut and secure the head respectively. A first biasing mechanism that biases the carriage horizontally and vertically is provided.

Therefore, the head carriage is always moved and tilted while being in contact with the lead screw. Even if some parts of the reed / screw and these needles / sliding parts are abraded to some extent by friction, the first urging mechanism ensures contact between them, and thus rattling occurs. It hardly happens. Further, since the contact between the lead screw and the needle and each sliding portion is in the horizontal and vertical directions, friction occurs in the horizontal and vertical directions, and the transfer accuracy of the head carriage by the lead screw is always kept high. It

Description of Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an outline of a recording / reproducing unit of a magnetic recording / reproducing apparatus, and a plan view of FIG. 3 is a sectional view taken along the line III-III of FIG. 2, FIG. 4 is a view seen from the line IV-IV, FIG. 5 is a view seen from the line VV, and FIG. FIG. 7 is a sectional view taken along the line VII-VII, and FIG. 7 is a sectional view taken along the line VII-VII.

Referring to FIG. 1, FIG. 2 and FIG. 3, the recording / reproducing unit 1 is assembled on the substrate 2. A spindle motor 5 is attached to the substrate 2 at substantially the center thereof. The spindle motor 5 chucks and rotates a magnetic disk (shown by a chain line MD) in a video floppy (not shown). Further, two pins 6 and 7 are erected on the substrate 2. The pins 6 are for positioning the video floppy, and the video floppy is positioned by inserting the pins 6 into the positioning holes of the mounted video floppy. The pin 7 is used for positioning a regulation plate holder (not shown) to which a regulation plate that is in contact with the magnetic disk MD in the video floppy is fixed.

A lead screw 20 having a screw portion 21 formed on one end is horizontally and rotatably provided on the substrate 2. The lead screw 20 has bearings 4 at both ends.
It is rotatably supported by 0,50. The bearing 40 includes a pedestal 41 having a flat horizontal receiving surface 41a fixed on the substrate 2 and a receiving post 42 having a circumferential vertical receiving surface 42a (see FIG. 5). Further, the bearing 50 includes a pedestal 51 having a flat horizontal receiving surface 51a fixed on the substrate 2 and a receiving column 52 having a semicircular vertical receiving surface 52a) (see FIG. 6). As will be described later in detail, both ends of the lead screw 20 having the circumferential surface are provided with the horizontal bearing surfaces 41a and 51a and the vertical bearing surfaces of the bearings 40 and 50.
42a and 52a are pressed against each other by the force of a spring and linearly contacted with these surfaces to be rotatably received. A stopper 43 is attached to the bearing 40, and a leaf spring 53 is attached to the bearing 50. The leaf spring 53 contacts one hemispherical end surface of the lead screw 20 and presses the other end surface against the stopper 43. Prevents the lead screw 20 from moving in the longitudinal direction. Further, the bearings 40, 50 are provided with stoppers 44, 54 for preventing the bearings 40, 50 from having a portion located above the lead screw 20 to prevent them from falling off. There is a slight gap between the stoppers 44, 54 and the lead screw 20.

A worm gear 27 is fixed on the opposite side of the screw portion 21 of the lead screw 20. The worm gear 27 meshes with a worm 28 fixed to an output shaft 29a of a step motor 29 (shown by a broken line in FIG. 2). Step motor
The numeral 29 is fixed to the back side of the board 2, and the output shaft 29a of the board 2 is loosely passed through the hole formed in the board 2 to advance to the front side. By driving the step motor 29, the lead screw 20 is rotated.

The head carriage 10 is composed of a sliding portion 11 and a head mounting portion 12 which are integrally formed, and these are connected to each other at one end thereof so as to form an L-shape when seen in a plan view.

A concave portion 16 is formed in the sliding portion 11 in the longitudinal direction thereof,
The lead screw 20 passes through the recess 16. Except for the end portion of the sliding portion 11 to which the head mounting portion 12 is coupled, this recess 16 is open on the spindle 5 side. Recess
Of course, the bottom side is open in all 16 parts. The recess 16 has a horizontal surface 16a facing downward and a vertical surface 16b facing inward. At one end of the sliding portion 11 located toward the worm gear 27, a portion slightly protruding from the both surfaces 16a, 16b of the concave portion 16 is formed, and these protruding portions form a flat horizontal sliding surface 14a orthogonal to each other. It has a vertical sliding surface 14b (see FIG. 7). These sliding surfaces 14a, 14b are in a relationship of facing the receiving surfaces 51a, 52a of the bearing 50 (and the surfaces 41a, 42a of the bearing 40), respectively.

At the other end of the sliding portion 11, that is, at the joint with the head mounting portion 12, a needle 22 that engages with the valley of the screw portion 21 of the lead screw 20 is embedded. The needle 22 is provided diagonally across the upper portion of the recess 16 and substantially parallel to the horizontal plane 16a. The vertical surface 16b of the recess 16 is provided with a protruding sliding portion 13 that comes into contact with the threads of the screw portion 21 of the lead screw 20. The protruding sliding portion 13 extends in the vertical direction.
It is preferable that the protruding sliding portion 13 is located in the thread adjacent to the valley of the threaded portion 21 with which the needle 22 is engaged, but it is not necessarily required to be adjacent. As will be described later, with a spring,
The sliding surfaces 14a and 14b are on the circumferential surface of one end of the lead screw 20 other than the threaded portion 21, and the needle 22 and the protruding sliding portion 13 are the troughs of the threaded portion 21 at the other end of the lead screw 20. The head carriage 10 and the lead screw 20 are urged so as to contact with the mountain and the mountain, respectively.

A recess is formed near the center of the head mounting portion 12 of the head carriage 10, and a mounting piece 19 protruding upward is provided in this recess. The magnetic head 18 has a mounting member 17
It is fixed to the mounting piece 19 via.

A step portion is provided at the end portion of the head mounting portion 12 on the side opposite to the joint portion with the sliding portion 11, and the horizontal portion 15 and 16 are provided on the step portion.
Are formed. The horizontal surface 16 is formed at the tip of the head mounting portion 12. A rod 36 having both ends supported by a pedestal 32 integrally formed with the seat 30 passes on the horizontal surface 15. The pedestal 30 is fixed to the substrate 2. The pedestal 32 has a vertical surface 32a and a horizontal surface 32b which are orthogonal to each other (see FIG. 4). The rod 36 is fixed by being biased by a leaf spring 34 attached to the pedestal 32 so as to abut against the surfaces 32a and 32b, respectively. As will be described later, the end of the head mounting portion 12 is urged upward by the force of the leaf spring 23, and the horizontal surface 15 thereof abuts the rod 36.

A latch solenoid 31 is fixed to the seat 30.
In the latch solenoid 31, for example, a positive pulse signal causes the output shaft 37 to rotate + 10 °, and a negative pulse rotates -10 °. Output shaft 37
A swing member 33 is fixed to the. The swinging member 33 is provided with a portion projecting upward at its tip, and the lower surface of this projecting portion has a horizontal plane of the head carriage 10 in the operating position.
A slanted surface 33a that engages with 16 is formed (see FIG. 3). The latch type solenoid 31 can be driven by a pulsed current, and thus has an advantage of saving power consumption.
By driving the latch solenoid 31, the swinging member 33 takes the operating position shown by the chain line and the stopping position shown by the solid line.

In particular, referring to FIG. 3, a recess is formed on the back side of the head mounting portion 12, and the leaf spring 23 is fixed to the recess at the central portion thereof. One end 26 of the leaf spring 23 is bent into a substantially L shape and hits the threaded portion 21 of the lead screw 20 diagonally from below, pushing the lead screw 20 diagonally upward as indicated by arrow A. . A protrusion 24 is provided on the lower surface of the tip of the other end 25 of the leaf spring 23 and hits the substrate 2. As a result, the end of the head mounting portion 12 on which the horizontal plane 15 is provided is upward as shown by an arrow D. The pushing force is working. This causes the horizontal surface 15 to hit the rod 36. head·
A recess 16 is formed on the lower surface of the head mounting portion 12 of the carriage 10.
A notch 12a is formed to connect to the end portion 26 of the leaf spring 23 to ensure the action.

On the other hand, another leaf spring 46 is attached to an attachment base 48 provided on the substrate 2 at one end thereof. A protrusion 47 is provided on the back surface of the other end of the leaf spring 46, and
The sliding portion 11 of the carriage 10 is in contact with the upper surface of the sliding portion 11 at approximately the center in the longitudinal direction. The position where the protrusion 47 abuts on the sliding portion 11 is slightly outside the position just above the lead screw 20. As shown by an arrow B, a vertical force acting downward is applied to the sliding portion 11 of the head carriage 10. A stopper 45 is attached to the mount 48 along with the leaf spring 46. There is a slight gap between the stopper 45 and the sliding portion 11.

Referring also to FIGS. 1 and 2, a shaft 49 is erected on the substrate 2 next to the mounting base 48 on the substrate 2, and a pressing lever is attached to the shaft 49.
55 is slidably provided in the horizontal direction. Pressure lever
55 is formed in a vertical U-shaped cross section. One end of the upper surface piece 56 of the pressing lever 55 extends horizontally along the side surface of the sliding portion 11 of the head carriage 10 up to the position where the protrusion 47 of the leaf spring 46 contacts the head carriage 10, A protruding portion 56b that horizontally protrudes toward the sliding portion 11 of the head carriage 10 is formed at the tip thereof. The protruding part 56b is a sliding part
It abuts 11 sides. The contact positions of the protrusion 47 of the leaf spring 46 and the protrusion 56b of the pressing lever 55 are both on the same straight line orthogonal to the moving direction of the head carriage 10. A spring mounting portion 56a is formed at the other end of the upper surface piece 56 of the pressing lever 55. On the other hand, a mounting member 58 having a spring mounting portion 58a is fixed to the mounting base 48. And pull spring
59 is hung between these mounting parts 56a and 58a.
Therefore, the pressing lever 55 is biased by the spring 59, and a horizontal force acting on the sliding portion 11 of the head carriage 10 toward the lead screw 20 shown by an arrow C in FIG. 3 is applied.

The downward downward strong force B of the leaf spring 46 and the horizontal force C of the pressing lever 55 cause the sliding surfaces 14a and 14b of the sliding portion 11 of the head carriage 10 to come into contact with the lead screw 20. The protruding sliding portion 13 contacts the thread of the threaded portion 21, and the lead screw 20 abuts the horizontal bearing surfaces 41a and 51a and the vertical bearing surfaces 42a and 52a of the bearings 40 and 50 at both ends thereof. Needle 22 as well as lead screw 20
Engages with the troughs of the threaded portion 21. The force A by the end portion 26 of the leaf spring 23 leads to a direction almost opposite to the combined force of the forces B and C.
The screw 20 is pressed against the sliding portion 11 to ensure contact between them.

When the lead screw 20 is driven to rotate, the needle
Since 22 is engaged with the screw portion 21, the head carriage 10 is transferred in the axial direction of the lead screw 20. The head carriage 10 is guided by the sliding surfaces 14a, 14b and the leads.
The contact with the screw 20, the protruding sliding surface portion 13 and the screw thread, and the horizontal surface 15 and the rod 36 are surely performed. It goes without saying that the projecting sliding portion 13 is always in contact with the thread of the screw portion 21 because the head carriage 10 is transferred as the lead screw 20 rotates.
In this way, the magnetic head 18 mounted on the head carriage 10 moves in the radial direction of the magnetic disk MD contained in the video floppy disk. Head carriage 10
The range of the reciprocating movement of is shown by L in FIG.

In a normal state in which recording on the magnetic disk MD or reproduction from the magnetic disk MD by such a magnetic head 18 is possible, as is often shown in FIG.
Force keeps the head carriage 10 horizontal, and the magnetic head 18 is in close contact with the surface of the magnetic disk MD. At this time, the swinging member 33 of the latch-type solenoid 31 has the second
It is waiting at the stop position shown by the solid line in the figure.

When the latch type solenoid 31 is activated, the swing member 33 rotates to the operating position indicated by the chain line. Slope 33a of swing member 33
And the edge of the horizontal plane 16 of the head carriage come into contact (see FIG. 3), and the swinging member 33 pushes this end of the head carriage 10 downward, so that the head carriage 10 is shown in phantom in FIG. Rotate slightly around the lead screw 20 as shown. The head carriage 10 tilts obliquely and the magnetic head 18 separates from the magnetic disk MD. In this way, the magnetic head 18 is retracted.

The above retracting operation of the magnetic head 18 is performed by the head carriage.
It is possible at any position within the reciprocating range L of 10. At the stop position shown by the solid line, the swinging member 33 of the solenoid 31 is positioned at the horizontal plane 16 regardless of the position of the head carriage 10.
Has no effect on the edge of.

When the latch solenoid 31 rotates in the reverse direction and the swing member 33 returns to the stop position, the head carriage 10 returns to the attitude in which the magnetic head 18 contacts the magnetic disk MD by the biasing force of the leaf springs 23 and 46.

In the above-described embodiment, the head carriage 10 is provided with the recess 16 into which the lead screw 20 is fitted. However, instead of this, the parts other than the screw part 21 of the lead screw 20 are rotatable and slidable. The head carriage 10 may be provided with a guide portion having a through hole freely passing therethrough.

[Brief description of drawings]

FIG. 1 is a perspective view showing the outline of a recording / reproducing unit of a magnetic recording / reproducing apparatus, and FIG. 2 is a plan view thereof. 3 is a sectional view taken along the line III-III of FIG. 2, FIG. 4 is a view seen from the line IV-IV, FIG. 5 is a view seen from the line VV, and FIG.
The drawing is a view taken along the line VI-VI, and FIG. 7 is a sectional view taken along the line VII-VII. 1 …… recording / reproducing section, 2 …… substrate, 10 …… head carriage, 11 …… sliding section, 12 …… head mounting section, 13 …… protruding sliding section, 14a, 14b …… sliding surface , 16 horizontal surface, 18 magnetic head, 20 lead, screw, 21 screw part, 22 needle, 23,46 leaf spring, 31 latch type solenoid, 33 swing Member, 33a …… Slope, 36 …… Output shaft, 55 …… Pressing lever, 59 …… Tension spring, MD …… Magnetic disk.

Claims (2)

[Claims] 1. A recording / reproducing magnetic head, wherein the recording / reproducing magnetic head is movably supported by a support shaft so as to move in the radial direction of a magnetic disk, and the support shaft is provided. A head carriage that is tiltable in the center, and the head carriage is centered on the support shaft in a direction in which the recording / reproducing magnetic head moves away from the magnetic disk when the recording / reproducing magnetic head is in contact with the magnetic disk. In a magnetic head retracting mechanism in a magnetic recording / reproducing apparatus including a mechanism for tilting, and a board on which the head carriage and the tilting mechanism are mounted, a screw portion is formed at a position near the one end of the spindle. The lead screw is rotatably supported by bearings provided on the substrate at both ends of the lead screw. A horizontal sliding portion and a vertical sliding portion, which are located at a position near the other end of the screw and which come into contact with portions other than the threaded portion in a direction substantially orthogonal to each other, are formed on the head carriage, and the lead carriage is provided. A needle that fits in the groove of the screw of the screw is provided substantially horizontally on the head cage, and a protruding sliding portion that abuts the thread of the screw is provided near the position of the needle. -The carriage is formed almost vertically, and the horizontal sliding portion and the vertical sliding portion are on the peripheral surface near the other end of the lead screw, and the needle is on the groove of the screw portion of the lead screw. A first urging mechanism for urging the head carriage in substantially horizontal and vertical directions is provided on the substrate so that the protruding sliding portions come into contact with the threads of the threaded portion. A magnetic head retracting mechanism in a magnetic recording / reproducing device. 2. A second urging mechanism for urging the lead screw in a direction opposite to the urging direction of the first urging mechanism, wherein a second urging mechanism is provided. A magnetic head retracting mechanism in the magnetic recording / reproducing apparatus according to item 1.