JPS6182383A - Magnetic recorder - Google Patents

Abstract

PURPOSE:To stop securely a magnetic head on a recording medium at the time of the CPU runaway by detecting that the magnetic head reaches a moving position limit so as to stop the action of the CPU and absorbing inertial force by means of a stopper. CONSTITUTION:When a magnetic head 3 which is stopped at the home position of a zero track through a zero track sensor 9 at the time of the normal action of a CPU moves further, an interrupter member 7 is rotated further clockwise by means of an actuator 6 and pulley 5, and the optical path of a moving position limit sensor 9 is cut off. Then a detection output through an arithmetic amplifier inverts to 'L', and the CPU is reset through an FF, etc., and stops its action, thereby stopping an actuator drive motor. The fitting part of a sensor 8 abuts on a stopper 10 to absorb the inertial force of the drive motor, etc. Thus the magnetic head is securely stopped on a disk 1 of a recording medium at the time of the CPU runaway, and the resumed read and write are carried out without hindrance.

Description

[Detailed description of the invention] [Industrial application fields] The present invention relates to a magnetic recording device.

[Prior Art] Conventionally, in a magnetic recording device, information is written or read by controlling a magnetic head to move back and forth in the radial direction on a magnetic disk, which is a storage medium, to position the magnetic head at a corresponding track position. I try to do this. In this case, a zero track position is provided at a predetermined position on the outer periphery of the magnetic disk, and when the magnetic head reaches the zero track position, for example, an optical zero track sensor is used to control the movement of the magnetic head by rotation of a stepping motor. The rotating interrupter member is detected and output to a central processing unit (CPU), which stops the operation of the stepping motor and determines the home position of the magnetic head.

[The problem that the invention seeks to solve.]

However, in such a device, if the CPLI program runs out of control for some reason, the magnetic head is not stopped even though the zero track sensor has detected the zero track position, and is moved further to the outside of the magnetic disk.
As a result, there are problems in that the magnetic head comes off the magnetic disk, making it impossible to write or read information, or damaging the magnetic head and the magnetic disk.

This invention was made to solve these problems, and the purpose is to provide a magnetic recording device that can reliably stop the magnetic head on the storage medium even if the central processing unit goes out of control. do.

[Means for Solving the Problems] This invention provides a disc-shaped storage medium for storing information;
A rotation mechanism is provided to fix the storage medium and rotate it at a constant speed, and a rotation mechanism is provided that is movable in the radial direction of the storage medium rotated by this rotation mechanism, and is provided to write and read information to and from the storage medium. a stepping motor that controls the movement of the magnetic head; a member that is attached to the rotating part of the stepping motor and rotates with the rotation of the motor; A zero track sensor detects the zero track by detecting the rotational position of the member when it moves to the track position, and a magnetic head is installed near the zero track sensor to move the magnetic head to a predetermined position outside the zero track position on the storage medium. a movement position limit sensor that detects the position of the member when it moves; a stopper that is provided on the member and forcibly stops rotation of the member when the member is detected by the movement position limit sensor; a rotation mechanism; The apparatus is equipped with a central processing unit that programmatically controls the head, stepping motor, zero track sensor, etc., and means for stopping the operation of the central processing unit in response to a component detection output from a movement position limit sensor.

[Function] By having such a configuration, the present invention has such a configuration that even if the central processing unit runs out of program and the magnetic head is moved outside the zero track position of the storage medium, the movement position limit sensor is detected and the operation of the central processing unit is stopped, and furthermore, when the magnetic head cannot be stopped immediately due to inertia force, a stopper is used to reliably stop the magnetic head at the movement position limit position.

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

FIG. 1 is a partial view showing the m configuration of the main part, where 1 is a magnetic disk which is a storage medium, and 2 is a plate that is a presser for fixing this magnetic disk 1. The presser base 2 is rotated together with the magnetic disk 1 by a spindle motor, which will be described later. Reference numeral 3 denotes a magnetic head, and reference numeral 4 attaches the magnetic head 3 to its tip, and is rotatable clockwise and counterclockwise around the other end. 5 is a pulley that is rotatably operated by a stepping motor that reaches the end of the arm 4; 6 is a pulley whose end surface is in contact with the pulley 5 via a belt, and the other end is connected to the same shaft as the arm 4; This is an actuator that is rotatably provided. That is, the relationship among the arm 4, pulley 5, and actuator 6 is such that when the pulley 5 is rotated by the stepping motor, the actuator 6 rotates clockwise or counterclockwise around the other end, thereby causing the arm to rotate. 4 is designed to rotate. The tip of the actuator 6 is fan-shaped, and the rotation range of the pulley 5 is determined by the length of the tip. This rotation range is determined so that the magnetic head 3 can move in the radial direction of the magnetic disk 1 with sufficient margin. An interrupter member 7 that rotates with the rotation of the pulley 5 is attached to the lower part of the pulley 5, and when the magnetic head 3 just reaches the zero track position on the magnetic disk 1, the interrupter member 7 is positioned to interrupt the optical path. For example, an optical zero track sensor 8 is provided. In the vicinity of the zero track sensor 8, when the magnetic head 3 passes through the zero track position, moves further outward, and comes just before the position where it comes off the top of the magnetic disk 1, the optical path is interrupted by the interrupter member 7. For example, an optical movement position limit sensor 9 is provided at the position. A stopper 10 is provided at the left end of the interrupter member 7, and when the interrupter member 7 rotates to a position where it blocks the optical path of the movement position limit sensor 9, the stopper 10 stops at the fixed member to which the zero track sensor 8 is attached. When the interrupter member 7 comes into contact with the interrupter member 7, further rotation of the interrupter member 7 is forcibly stopped.

FIG. 2 shows a circuit showing a control section, and 11 is a reset terminal RE.
A central processing unit (hereinafter referred to as CPU) with SET.

), 12 is an I10 port, and 13 is a transmission interface. The CPU 11 has a built-in ROM that stores program data, a RAM that stores control information, and the like. The CPU 11 controls the I10 port 12 via a pass line 14, and controls the magnetic head 3.
It outputs information to and takes in information from the head thereof, takes in information from the zero track sensor 8, and controls the motor drive circuit 15 to drive the stepping motor 16 and motor drive circuit 17 described above.
is controlled to drive the spindle motor 18 mentioned above. Further, the CPU 11 controls the transmission interface 13 via the path line 14, and controls the transmission of information and signals with the host computer.

The movement position limit sensor 9 includes a light emitting element 9a and a light receiving element 9b, and the output of the light receiving element 9b is supplied to an input terminal of an operational amplifier 19.

A reference voltage from a reference voltage setting circuit 20 is input to one input terminal of one of the operational amplifiers. The output of the operational amplifier 19 is supplied to the input terminal of a D-type flip-flop 22 via an inverter circuit 21. The flip-flop 22 outputs the output from its output terminal Q to the CPU 1.
1 reset terminal RESET. In addition, the above-mentioned flip.

A signal from an initial reset circuit 23 that operates when the power is turned on is input to a clear terminal C of the flip-flop 22.

The CPU 11 starts the program control operation shown in FIG. 3 when the power is turned on or when a reset pulse is input to its reset terminal RESET.

That is, first, the ports and RAM are initialized, and then the rotation of the spindle motor 18 is started. Then, it is checked whether the spindle motor 18 is rotating normally or not, and if it is abnormal, the progress of the program is stopped. Further, if the spindle motor 18 is rotating normally, it is next checked to see if there is any abnormality in anything other than the spindle motor 18, and if there is an abnormality, a write inhibit output is sent out to stop the transition program control. If there is no abnormality as a result of this check, the magnetic head 3 is moved to a position where the zero track sensor 8 detects the interrupter member 7 and set at the home position.

Subsequently, the write protection is canceled and the movement of the magnetic head 3 is controlled by signal input from the host computer to write and read information.

In the device according to the embodiment of the present invention having such a configuration, the CPU 1
As long as the magnetic head 1 is operating normally without program runaway, the magnetic head 3 is always set at the zero track position and positioned at the home position to write and read information on each track.

However, if the CPL11 program goes out of control for some reason, positioning at the home position becomes impossible, and for example, a situation occurs in which the magnetic head 3 is moved further outside the zero track position. When such a situation occurs, the interrupter member 7 will further rotate clockwise due to the rotation of the pulley 5. Thus, the optical path of the movement position limit sensor 9 is interrupted by the interrupter member 7. When this happens, the output of the operational amplifier 19 is inverted from high level to low level, and the output of inverter 21 is inverted from low level to high level. As a result, the 7-lip flop 22 is set by the rise of the signal, and the reset signal continues to be supplied to the reset terminal RESET of the CPU 11. This keeps the cpuil in a reset state and completely stops its operation. At this time, even if the operation of the CPU 11 is stopped due to the inertia of the arm 4 or the actuator 6, the magnetic head 3 does not stop immediately, and even if it attempts to move outside the magnetic disk 1, the stopper 10
However, the installation of the zero track sensor 8 contacts the member and prevents the ink club member 7 from rotating further counterclockwise, so the rotation of the stepping motor 16 is immediately stopped and the magnetic head 3 is prevented from moving further outward. is definitely prohibited. Therefore, the movement of the magnetic head 3 is reliably and quickly stopped, and the magnetic head 3 is reliably prevented from coming off the magnetic disk 1.

In this way, even if the CPU 11 runs out of control, the magnetic head 3 may move too far outside and become detached from the magnetic disk 1, making it impossible to read or write information. There is no risk of damage.

In addition, in the above embodiment, an example was described in which optical sensors were used as the zero track sensor and the moving position limit sensor, but the sensor is not necessarily limited to this, and for example, a micro switch may be used. .

[Effects of the Invention] As detailed above, according to the present invention, even if the central processing unit goes out of control, the magnetic head can be reliably stopped on the storage medium, making it impossible to write or read information. Therefore, it is possible to provide a magnetic recording device in which there is no risk of damage to the magnetic head or recording medium.

[Brief explanation of drawings]

The figures show an embodiment of the present invention, in which Fig. 1 is a partial diagram showing the configuration of the main part, Fig. 2 is a circuit diagram of the main part, and Fig. 3 is a CPU.
2 is a flowchart showing main part processing by. 1...Magnetic disk, 2...Platform with presser, 3...
Magnetic head, 4...arm, 5...pulley, 6...
・Actuator, 7... Interrupter member, 8...
・Zero track sensor, 9... Movement position limit sensor, 10... Stopper, 11... Central processing unit (CPU), 16... Stepping motor, 18...
... Spindle motor, 19... Operational amplifier, 22.
...D type flip-flop.

Claims (1)

[Claims] A disc-shaped storage medium for storing information, a rotation mechanism for fixing the storage medium and rotating it at a constant speed, and a rotation mechanism for rotating the storage medium at a constant speed, and a disk-shaped storage medium for storing information, and a rotation mechanism for rotating the storage medium at a constant speed. a magnetic head that writes and reads information to and from the storage medium; a stepping motor that controls the movement of the magnetic head; and a member that is attached to the rotating part of the stepping motor and that rotates as the motor rotates. , a zero track sensor that detects the rotational position of the member to detect zero track when the magnetic head moves to a zero track position set on the outer circumferential side of the storage medium; and a zero track sensor provided near the zero track sensor. , a movement position limit sensor that detects the position of the member when the magnetic head moves to a predetermined position outside the zero track position on the storage medium;
a stopper provided on the member and forcibly stopping rotation of the member when the member is detected by the movement position limit sensor; the rotation mechanism; a magnetic head;
A magnetic recording device comprising: a central processing unit that programmatically controls a stepping motor, a zero track sensor, etc.; and means for stopping the operation of the central processing unit based on a member detection output from the movement position limit sensor. Device.