JPS62246187A - Magnetic head feeding device - Google Patents

Abstract

PURPOSE:To accurately set a position by forming transmission holes on a pair of coaxially arranged gears and detecting the position, where these transmission holes coincide with each other, by a detecting part and determining a home position or an end position based on of said position. CONSTITUTION:The rotational force of a stepping motor 43 is decelerated through a gear train 37; and when the stepping motor is driven by 12 steps, a magnetic head 38 is moved by one track on a magnetic disk 20 in a disk pack 12 because of the gear train 37 to record or reproduce data. If transmittance holes 56A and 58A are allowed to coincide with each other when the number of feed steps of the stepping motor 43 is 0, a gear 58 is rotated 25 times and the positions of transmittance holes 56A and 48A coincide with each other when the stepping motor 43 is driven by 650 steps and a gear 56 is rotated 26 times. The position where transmission holes 56A and 58A coincide with each other is detected by a detecting part 62 to bring the magnetic head 38 to the home position or the end position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head feeding device, and more particularly to a magnetic head feeding device for performing magnetic recording or magnetic reproduction on a cassette type magnetic disk.

[Background of the invention]

Recently, imaging devices such as solid-state imaging devices and image pickup tubes.

In combination with a recording device that uses a magnetic disk that is inexpensive and has a relatively large storage capacity as a recording medium, still images of the subject are captured purely electronically and recorded on a rotating disk, and images are played back using a separate television system or An electronic still camera system that uses a printer or the like has been developed.

In an image recording or reproducing system using such a magnetic disk, a disk with a diameter of about 50 mm is used, and this magnetic disk can record from 1 track to 52 trunks from the outer circumference to the inner circumference. A pattern is formed. The magnetic head feed pitch is about 100 μm, which is slightly smaller than the feed pitch of a normal floppy disk, and therefore the magnetic head must be moved with extremely high precision. Then, the home position, which is the starting position (movement start position) of the magnetic head, is set at a predetermined position on the outer circumferential side from one track or at one trunk position,
The end position, which acts as a reference position when sending the magnetic head in the radial direction of the magnetic disk to record or reproduce data, is the end position of the magnetic throat (movement end position) from the 52 track to a predetermined position on the inner circumference side. This prevents the magnetic head from moving beyond a predetermined recording range of the magnetic disk. Therefore, in the magnetic disk device in the electronic camera system, it is necessary to detect the home position and the end position and stop the feeding of the magnetic head at the home position or the end position.

Furthermore, since the home position acts as a reference position for forming each track when the magnetic head is sent in a fixed position to record on a magnetic disk, the home position is detected with high precision and the magnetic head is moved with high precision. It needs to be stopped.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides a magnetic head feeding device that detects the home position and end position of a magnetic head and stops the magnetic head at the home position or the end position. The purpose is to propose.

[Summary of the invention]

In order to achieve the above object, the present invention includes a rotary drive source, a head carriage that is provided with a magnetic head and moves while being guided by a guide member, and converts the driving force of the rotary drive source into linear movement of the carriage. A magnetic head feeding device for recording or reproducing data on or from a magnetic sheet by moving the magnetic head in a radial direction with respect to a magnetic sheet stored in a magnetic sheet pack. It operates in conjunction with a transmission means and consists of a plurality of coaxially arranged rotating bodies that rotate differentially, and a detection section that detects the differential movement of the rotating bodies, and detects the position of the carriage by detecting the differential movement. It is characterized by

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a magnetic head feeding device according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a plan view showing this embodiment. As shown in FIG. 1, a main body 10 of a cassette type magnetic disk recording device, such as an electronic camera or a reproducing device, has a rectangular shape. A disk back 12 is placed on this main body 10 as shown by the imaginary line in FIG.
are engaged and placed so as to be rotatable.

First, the structure of the disc back 12 will be explained. As shown in FIGS. 2(A) and 2(B), the disc back 12 includes a back main body 18 and a rotatable structure therein. 1 and 2 (A).
They are placed in the main body 10 of the magnetic disk drive with their surfaces facing upward so that the end faces indicated by arrow A are common.

The magnetic disk 20 is composed of a disk-shaped magnetic recording material 22 with a recording layer formed on the back surface, and a center core 26 provided with a hole 24 in the center to engage with the rotating wheel 16 of the disk drive motor 14. The back body 18 is a magnetic disk 20
an aperture 28.30 for exposing the center core 26 of the
It has apertures 31 and 32 for exposing the recording surface and non-recording surface of the magnetic disk 20, and a magnetic head can be protruded from the aperture 32 onto the recording surface to perform recording or reproduction. There is. The member indicated by the two-dot chain line 33 is a shutter, and when the bag main body 18 is inserted into the playback device,
When taken out, the shutter 33 slides and opens the openings 31 and 3.
Open and close 2.

Now, as shown in FIG. 1, a head carriage 36 is slidably disposed in the main body 10 of the apparatus.

That is, the head carriage 36 is equipped with a magnetic head 38 that performs magnetic recording or reproduction on the magnetic disk 20 in the disk back 12, and slides in the left-right direction in FIG. Free to move. The rotational force of the stepping motor 43 is applied to the gear train 3.
7 to the head carriage 36, and the head carriage 36 is slightly moved. That is, a gear 46 is provided on the output shaft 44 of the stepping motor 43, and this gear 46 meshes with a gear 50 provided on the intermediate shaft 48. A screw gear 52 is provided on the intermediate shaft 48, and a pin 54 projecting laterally from the head carriage 36 meshes with the screw gear 52. In this way, the rotational force of the stepping motor 43 is transmitted to the head carriage 36.

Next, a device for detecting the home position and end position of the magnetic head 38 will be explained. Gears 56 and 58 disposed coaxially with the shaft 60 mesh with the gear 46 of the output shaft 44. The gear 56 is formed to have a number of teeth 256=25, and the gear 58 is formed to have a number of teeth Zss"26. In order to mesh the gears 56.58 with different numbers of teeth with the common gear 46, the gear 56.58 and the gear 58 are Gears 56 and 58 are further provided with through holes 56A and 58A, as shown in FIG. ing.

The detection unit 62 includes a light emitting element 62A and a light receiving element 62B, and sends a signal to the stepping motor 43 to control the movement of the stepping motor 43 when the through holes 56A and 58A of the gears 56 and 58 are aligned.

The operation of the embodiment according to the present invention constructed as described above is as follows.

First, the rotational force of the stepping motor 43 is the gear train 3
7. The stepping motor 43 rotates 18 degrees in one step. The gear train 37 drives the stepping motor 12 steps, and when the speed is reduced by the gear train 37, the head carriage 36 can be moved by 100 microns. In this way, the magnetic head 3B can be moved one track (100 microns) at a time to the magnetic disk 20 in the disk back 12 to perform recording or reproduction.

Further, the positional relationship between the through holes 56A and 58A of the gears 56 and 58 is as shown in FIG. In the table shown in Figure 4,
If the through holes 56A and 58A are aligned when the number of feed steps of the stepping motor 43 is O, the gear 56 (number of teeth Zsb = 25) will rotate once in 25 steps, and the gear 58 (number of teeth Zss'''26) will rotate 25 times. When the stepping motor 43 is rotated 650 steps and the gear 56 (Z, b=25) rotates 26 times, the gear 58 (zS, = 26) rotates 25 times, and the through holes 56A, 5 rotate.
The position of 8A matches. Therefore, the stepping motor 43
When the number of feed steps is O is set as the home position, and when the number of feed steps is 650 steps is set as the end position, the detection unit 62 detects the position where the through holes 56A and 58A match, and the head The carriage 36 can be stopped and the magnetic head 38 can be positioned at the home position or the end position.

FIG. 5 shows another embodiment of the invention. In the embodiment shown in FIG. 5, the same or similar members in the embodiment shown in FIG. 1 are given the same reference numerals and their explanations will be omitted. In the embodiment shown in FIG. 1, gears 56 and 58 having different numbers of teeth are meshed with the same gear 46 by gear shift, but the invention is not limited to this.
As in the embodiment shown in FIG.
1 is attached, a gear 70 is meshed with the gear 58, and a gear 71 is further meshed with the gear 56.

Even in this case, the rotational force from the stepping motor 43 is transmitted to the gear 56.58, and the through hole 5 of the gear 56.58
The detection device 62 detects the position where the positions of 6A and 58A match, and thereby the magnetic head 3 can be stopped at the home position or end position.

In the embodiment described above, a coaxial gear was used as the detection member, but the detection member is not limited to the gear, and a rotating disk or the like may be used.

〔Effect of the invention〕

As explained above, according to the magnetic head feeding device according to the present invention, through-holes are formed in a pair of coaxially arranged gears, the detection unit detects the position where the through-holes coincide, and the position where the through-holes coincide with each other is detected. Since the home position or end position is determined from the position, the home position or end position can be set accurately.

[Brief explanation of drawings]

Figure 1 is a plan view showing the overall structure of this embodiment, and Figure 2 (A
) and FIG. 2(B) are front and back views showing the magnetic disk bank used in the above embodiment of the present invention, FIG. 3 is a cross-sectional view of the main part of this embodiment, and FIG. FIG. 5 is a front view of another embodiment. 10...Main body of magnetic disk recording or reproducing device,
20... Magnetic disk, 36... Head carriage, 38... Magnetic head, 56.58.
...Gear, 56A, 58A...Through hole, 60...
axis, 62...detection section;

Claims (1)

[Claims] It consists of a rotational drive source, a head carriage that is provided with a magnetic head and moves while being guided by a guide member, and a transmission means that converts the driving force of the rotational drive source into a linear motion of the carriage and transmits it. In a magnetic head feeding device in which a magnetic head moves in a radial direction with respect to a magnetic sheet stored in a sheet pack to perform recording or reproduction on the magnetic sheet, a magnetic head that operates in conjunction with the transmission means and coaxially moves. 1. A magnetic head feeding device comprising a plurality of disposed rotating bodies that rotate differentially and a detection section that detects the differential movement of the rotating bodies, and detects the position of a carriage by detecting the differential movement.