JPH0438071B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a floppy disk drive device.

[Technical background of the invention and its problems]

A floppy disk drive device is equipped with a spindle that is rotated by a motor, and the inserted floppy disk is held and rotated by the spindle, and a pulse motor is used to move a magnetic head in the radial direction of the floppy disk to write information on the floppy disk. Reading is in progress. Such a floppy disk drive device is connected to a host computer to control the rotation of the spindle motor and pulse motor, and to control the writing and reading of information.

Conventionally, in floppy disk drive devices, for example, a stopper is provided outside a track zero position provided near the outer periphery of a floppy disk to stop the outward movement of a magnetic head placed on a carrier. When the power is turned on, a specific excitation phase of a pulse motor, which is a drive device for the magnetic head, is energized, and the magnetic head is stopped at a position corresponding to the excitation phase. Therefore, if the set position of the stopper is set to the optimal position with respect to the track zero position, the magnetic head, which was stopped at the stopper position before the power is turned on, can be energized to at least reach the track zero position. It can be moved circumferentially and stopped.

However, if the set position of the stopper is too far away from the track zero position, the magnetic head will tend to move to a track position outside the stopper of the same phase. Therefore, the magnetic head stops in a state where it is pressed against the stopper, and unnecessary stress is applied to the magnetic head and the stopper. There is a risk of being wrong. Therefore, the position of the stopper must be precisely set to avoid such problems, which poses the problem of increased installation and adjustment work time.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its purpose is to move the magnetic head inward by a certain distance and stop it when the power is turned on. It is an object of the present invention to provide a floppy disk drive device that can prevent excessive stress from being applied to the floppy disk drive device, and furthermore, to provide a floppy disk drive device that can simultaneously detect the track zero position when the power is turned on.

[Summary of the invention]

In this invention, when the power is turned on, a pulse from a pulse generating means and a direction signal in the inner circumferential direction from a moving direction setting means are input to a driving means of a pulse motor that moves a carrier on which a magnetic head is placed. , the carrier is moved in the inner circumferential direction by a preset number of pulses and then stopped.
In another invention, after the above-mentioned stopping,
Conversely, it is moved toward the outer circumference by a predetermined number of pulses and then stopped. Furthermore, in another invention, when the track zero position detector detects the track zero position while the carrier is returning toward the outer circumference, the carrier is stopped at that position.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a floppy disk 3 is held by a spindle 2 which is rotationally driven by a motor 1. The floppy disk 3 is provided with a long hole 5 along its radial direction for bringing the magnetic head 4 into contact with the disk medium 3a. Note that 6 is an index hole for taking out an index signal. The magnetic head 4 is provided at the tip of a carrier 8 that moves along two parallel shafts 7a and 7b, and is movable in the radial direction of the floppy disk 3. Further, on the opposite side of the magnetic head 4, a holding body 9 for the disk medium 3a is provided so as to be movable up and down and placed on the carrier 8. A light shielding plate 10 is provided protruding from one side of the carrier 8, and when the magnetic head 4 is located at the zero track position (located at the outermost periphery) of the disk medium 3a, the light shielding plate 10 detects a zero track position detector. 11
It is set so as to shield light between the light emitting diode 11a and the phototransistor 11b that constitute the light emitting diode 11a. The carrier 8 is controlled to move over the shafts 7a and 7b by a pulse motor 12 via a belt or the like.

FIG. 3 shows the main circuit configuration, and the output of the track zero position detector 11 consisting of the light emitting diode 11a and phototransistor 11b shown in FIG. 2 is inputted to one input terminal of the three-input type NAND gate 21. are doing. The output of this NAND gate 21 is input to a control input terminal of a pulse generator 22 which generates step pulses at regular intervals. The step pulse signal a outputted from the pulse generator 22 is inputted to a drive circuit 25 for rotationally driving the pulse motor 12 via a pulse counter 23 as a pulse detection means and an OR gate 24 .
The other input terminal of the OR gate 24 receives a step pulse signal Stp from a host computer (not shown).
is input. On the other hand, the output of the pulse counter 23 is input to a moving direction setting circuit 26 which outputs a direction signal b defining the rotating direction of the pulse motor 12 corresponding to the moving direction of the magnetic head 4. The direction signal b output from the movement direction setting circuit 26 is input to the drive circuit 25 via the OR gate 27. A direction signal Dir from a host computer (not shown) is input to the other input terminal of the OR gate 27.

In the drive circuit 25 , the direction signals b, Dir
The output of the OR gate 27 into which is input is input to one input terminal of exclusive OR gates 28 and 29, respectively. The output of the exclusive OR gate 28 is input to the D input terminal of a D-type flip-flop 30, and the output of the exclusive OR gate 29 is input to the D input terminal of a D-type flip-flop 31. Further, the output of the AND gate 24 to which the step pulse signals a and Stp are input is input to the T input terminals of the flip-flops 30 and 31, respectively. The output from the Q output terminal of the flip-flop 31 is input to the other input terminal of the exclusive OR gate 28, and is also output as the φC signal of the pulse motor 12. The Q output terminal output of the flip-flop 30 is outputted as a φB signal, and the output terminal output is outputted as a φD signal, and is inputted to the other ends of each of the NAND gate 21 and the exclusive OR gate 29. Further, the output from the output terminal of the flip-flop 31 is output as the φA signal and is also input to the remaining input terminals of the NAND gate 21. The signals φA, φB, φC, and φD form four-phase driving signals for the pulse motor 12. Each of the flip-flops 30,
31 is initially reset by an initial reset circuit 32 when the power is turned on.

Such a circuit configuration operates as follows when the power is turned on. That is, when the device is powered on,
A moving direction setting circuit 26, which is constituted by, for example, a flip-flop circuit, automatically sets the direction signal b to, for example, "1" so that the magnetic head 4 moves in the inner circumferential direction. Further, the pulse generator 22 starts outputting the step pulse signal a at regular intervals. At the same time, the pulse counter 23 starts counting the number of pulses of the input step pulse signal a. Also,
Direction signal from host computer when powering on
Dir and step pulse signal Stp are not input.
Therefore, the direction signal b and the step pulse signal a are transmitted to the pulse motor 1 via the OR gates 27 and 24.
The signal is input to the drive circuit 25 of No. 2. Thus, in the drive circuit 25 , each time the periodic step signal of the step pulse signal a is input, both flip-flops 30 and 31 operate, and the four-phase drive signals φA,
The pulse motor 12 is controlled to rotate in a direction in which φB and φC are sequentially changed to move the carrier 8 on which the magnetic head 4 is placed toward the inner circumference. Therefore, the magnetic head 4 moves inward from the position where it was stopped before the power was turned on. Next, when the count value in the pulse counter 23 measures a predetermined first setting value, for example, 3 pulses, the pulse counter 23 sends an inversion signal to the movement direction setting circuit 26 to reverse the movement direction of the carrier 8. Send signal c. When the moving direction setting circuit 26 receives the inverted signal c, it converts the direction signal b from "1" to "0". Therefore, the direction signal b is “1”
When the value changes from "0" to "0", the direction of change of the four-phase drive signals φA, φB, φC, and φD in the drive circuit 25 becomes opposite to that described above, and the pulse motor 12 rotates in the opposite direction. Therefore, the magnetic head 4 moves toward the inner circumference by three pulses from the stop position before the power is turned on, and then changes direction and moves toward the outer circumference. Next, when the magnetic head 4 reaches the zero track position of the floppy disk 3 while moving toward the outer circumference, the light shielding plate 1
0 is the light emitting diode 11a and the phototransistor 1
track zero position detector 1.
The output of 1 becomes "0" level. Therefore, the NAND gate 21 operates at the timing when the above output and the φA, φD signals become “0” and inputs the pulse stop signal d of “1” to the control input terminal of the pulse generator 22. Then, the pulse generator 22 stops outputting the step pulse signal a. Note that once the pulse generator 22 stops outputting, it will not generate pulses unless a start signal is applied from the outside. When the step pulse signal a is stopped (fixed to "0"), both flip-flops of the drive circuit 25 do not operate, so .phi.A and .phi.D are fixed to "0" and the rotation of the pulse motor 12 is stopped. Therefore, the magnetic head 4 stops at the zero track position.

Note that the magnetic head 4 is controlled by a circuit (not shown).
Even if the track zero position detector 11 is activated when the track zero position is activated while moving toward the inner circumference,
Pulse generator 22 does not stop.

Further, when the pulse counter 23 measures a predetermined second set value, for example, 5 pulses, while the magnetic head 4 is moving in the inner circumferential direction, the pulse stop signal d is sent to the pulse generator 22. Input to the control input terminal. As a result, the step pulse signal a is fixed at "0", and the pulse motor 1
2 stops rotating, and the magnetic head 4 stops at a midway position in the radial direction of the floppy disk 3 after a certain period of time has elapsed since the power was turned on.

After the magnetic head 4 has stopped at the track zero position or the halfway position, the host computer is activated, and the direction signal Dir and step pulse signal Stp are activated.
is input to the drive circuit 25 to control the rotation of the pulse motor 12.

In the floppy disk drive device constructed in this way, the magnetic head 4 moves in the inner circumferential direction by a preset number of pulses at the same time as the power is turned on. Therefore, the magnetic head 4, which was stopped close to or in contact with the stopper before the power is turned on, is always moved once in the inner circumferential direction, so that it stops while being pressed against the stopper when the power is turned on. There isn't. Therefore, since it is not necessary to set the position of the stopper precisely, the work of attaching and adjusting the stopper becomes easy. Further, the magnetic head 4 will not collide with the stopper and cause mechanical distortion of the floppy disk device.

Also, after moving the magnetic head 4 toward the inner circumference by a certain number of pulses, conversely moving it toward the outer circumference,
Since the track zero position is detected during movement in the outer circumferential direction and the magnetic head 4 is stopped at the track zero position, there is no need for the host computer to move the magnetic head 4 to the track zero position again. Therefore, it is also possible to increase the response speed of the entire floppy disk drive device.

FIG. 4 shows the main circuit configuration of a floppy disk drive device according to another embodiment of the present invention, and the same parts as in FIG. 3 are given the same reference numerals. Therefore, the explanation of the overlapping parts will be omitted.

In this embodiment, the track zero position detector 11 and the NAND gate 2 in the embodiment of FIG.
1 is removed. That is, at the same time as the power is turned on, the step pulse signal a and the direction signal b in the inner circumferential direction are applied to the drive circuit 25 from the pulse generator 22 and the movement direction setting circuit 26. After moving the magnetic head 4 toward the inner circumference by a preset number of pulses, the inversion signal c is input from the pulse counter 23 to the movement direction setting circuit 26, the level of the direction signal b is inverted, and the magnetic The head 4 is again moved toward the outer circumference by a separately preset number of pulses. Thereafter, a pulse stop signal d is input from the pulse counter 23 to the pulse generator 22 to stop the magnetic head. Thereafter, the movement of the magnetic head 4 is controlled by the host computer.

Even in the floppy disk drive device configured in this way, the magnetic head moves toward the inner circumference when the power is turned on, so that the effect of making the stopper installation and adjustment work easier is obtained, as shown in Fig. 3. .

FIG. 5 shows the main circuit configuration of a floppy disk drive device according to still another embodiment of the present invention, and the same parts as in FIG. 4 are given the same reference numerals. Therefore, the explanation of the overlapping parts will be omitted.

In this embodiment, the step pulse signal a and the inward direction signal b are applied to the drive circuit 25 from the pulse generator 22 and the moving direction setting circuit at the same time as the power is turned on. After moving the magnetic head 4 toward the inner circumference by a preset number of pulses,
The pulse counter 23 inputs a pulse stop d to the pulse generator 22 to stop the magnetic head 4.

In the floppy disk drive device constructed in this way, the same effects as in the embodiment shown in FIG. 4 can be obtained.

Note that the present invention is not limited to the embodiments described above. The embodiments shown in FIGS. 3 to 5 are as follows:
Although this invention is configured in hardware using logic circuits, it may also be configured in software using a microcomputer.

〔Effect of the invention〕

As explained above, according to the present invention, by moving the magnetic head a certain distance in the inner circumferential direction and stopping it when the power is turned on, the magnetic head is prevented from being pressed against the stopper or colliding with the stopper when the power is turned on. It can be prevented. Therefore, the installation of the stopper,
Adjustment work becomes easier.

Furthermore, the magnetic head can be stopped at the track zero position at the same time as the power is turned on, making it possible to increase the response speed of the entire floppy disk drive.

[Brief explanation of drawings]

Figures 1 to 3 show an embodiment of the present invention, in which Figure 1 is a plan view of the main part, Figure 2 is a side view of the main part, Figure 3 is a circuit diagram of the main part, and Figure 4 is a schematic diagram of the main part. The figure is a block diagram showing the main part of another embodiment of the invention, and FIG. 5 is a block diagram showing the main part of still another embodiment of the invention. 3...Floppy disk, 4...Magnetic head, 8...
Carrier, 11... Track zero position detector, 12
...Pulse motor, 22...Pulse generator, 23...Pulse counter, 25 ...Drive circuit, 26...Movement direction setting circuit.

Claims (1)

[Claims] 1. A magnetic head placed on a carrier is brought into contact with a rotating floppy disk, and the carrier is moved in the radial direction of the floppy disk using a pulse motor to write and read information on each track. In a floppy disk drive device, a pulse generating means outputs step pulse signals at regular intervals; a moving direction setting means outputs a direction signal for moving the carrier toward the inner circumference at least when the power is turned on; a driving means for driving the pulse motor based on the pulse signal and the direction signal; a pulse detecting means for measuring the number of pulses of the step pulse signal from the power-on time; and the number of pulses measured by the pulse detecting means. 1. A floppy disk drive device, further comprising means for inputting a pulse stop signal to the pulse generating means when the value reaches a predetermined set value. 2. A floppy disk drive device that writes and reads information on each track by bringing a magnetic head placed on a carrier into contact with a rotating floppy disk and moving the carrier in the radial direction of the floppy disk using a pulse motor. pulse generating means for outputting step pulse signals at regular intervals; moving direction setting means for outputting a direction signal for moving the carrier in the inner circumferential direction at least when the power is turned on; a driving means for driving the pulse motor based on the pulse motor; a pulse detecting means for measuring the number of pulses of the step pulse signal from the time when the power is turned on; When the set value of 1 is reached, a reversal signal for reversing the moving direction of the carrier is input to the moving direction setting means, and the pulse value is set to a second set value larger than the predetermined first set value. 1. A floppy disk drive apparatus, comprising: means for inputting a pulse stop signal to the pulse generating means when the pulse generating means reaches the pulse generating means. 3. A floppy disk drive device that writes and reads information on each track by bringing a magnetic head placed on a carrier into contact with a rotating floppy disk and moving the carrier in the radial direction of the floppy disk using a pulse motor. pulse generating means for outputting step pulse signals at regular intervals; moving direction setting means for outputting a direction signal for moving the carrier in the inner circumferential direction at least when the power is turned on; a drive means for driving the pulse motor based on the magnetic head; a track zero position detector for detecting arrival of the magnetic head at the track zero position; and a pulse detection means for measuring the number of pulses of the step pulse signal from the power-on time. When the number of pulses measured by the pulse detection means reaches a predetermined setting value, a reversal signal for reversing the moving direction of the carrier is input to the moving direction setting means, and after inputting this reversal signal, the A floppy disk drive apparatus comprising: means for inputting a pulse stop signal to the pulse generating means when the track zero position detector detects the track zero position.