JPH0770142B2 - Magnetic disk device - Google Patents

Description

The present invention relates to a magnetic disk device using a replaceable medium such as a floppy disk.

(Outline of the Invention) The present invention relates to an autoloading mechanism for automatically inserting or ejecting a magnetic disk as a recording medium into an apparatus by an electric means. The construction of the autoloading mechanism requires sensors to detect the start and end of insertion and ejection, but the present invention provides a control circuit that effectively reduces these sensors, and further It realizes a control circuit that takes stable measures against such operations and autoloading operations under unsteady conditions.

(Prior Art) In a conventional magnetic disk device having an auto loading mechanism, a sensor for detecting the start and the end is required, and the mechanism is complicated. Further, the driving motor is controlled only by determining whether or not these sensors detect the steady position state of the magnetic disk.

(Problems and objects to be solved by the present invention) However, in the above-mentioned conventional technology, when the movement of the medium is blocked by an artificial or external obstacle, the sensor for detecting this cannot detect the steady end state forever. The problem that the motor that consumes a relatively large amount of power continues to rotate and consumes unnecessary power, and that the motor continues to rotate under a large load condition due to the forced prevention of autoloading, which causes heat generation and the life of the motor to deteriorate significantly. Cause The present invention is intended to solve this problem and not to separately add an autoloading mechanism and a controlling sensor, but to use the magnetic disk device as a basic sensor in common.

Further, according to the present invention, the auto loading operation is started at the time of writing to the magnetic disk and the data on the medium is destroyed, and the auto loading section operation is added while the power is being consumed during the start-up of the motors. It prohibits increasing consumption.

(Means for Solving the Problem) A magnetic disk device of the present invention is a magnetic head for recording / reproducing on a replaceable magnetic disk, and a first sensor for detecting that the magnetic disk is inserted into the device. A second sensor for detecting that the magnetic disk is in a recordable / reproducible position, control means for controlling a recording / reproducing operation based on a signal from the second sensor, and insertion of the magnetic disk. In a magnetic disk device having an automatic loading mechanism for electrically loading and ejecting, when the magnetic disk is inserted, the first loading sensor drives the automatic loading mechanism based on a signal detected by the first sensor. The second sensor ends the driving of the auto-loading mechanism based on the signal detected by the magnetic disk, and the first sensor is started. Means for stopping the driving of the auto-loading mechanism if the second sensor does not detect the magnetic disk within a certain time after detecting the magnetic disk, and the second sensor when the magnetic disk is ejected. After the ejection of the magnetic disk is detected, if the first sensor does not detect the ejection of the magnetic disk within a predetermined time, it has means for stopping the driving of the autoloading mechanism.

(Operation) According to the above configuration of the present invention, the configuration of the auto loading mechanism is facilitated, and the magnetic disc, the mechanism and the motor in the magnetic disc device, and the power supply for driving the magnetic disc are protected against abnormal operation. And safety measures are taken.

(Embodiment) FIG. 1 is a block diagram of a magnetic disk device according to an embodiment of the present invention.

1 to 9 constitute a magnetic disk device, and signals are transmitted to and received from a computer 10 which is a host. Reference numeral 1 is a spindle motor for rotating a medium in the magnetic disk, and 2 is a magnetic head for contacting the magnetic disk to write / read data, which is connected to the R / W circuit 3. Reference numeral 5 is a step motor for driving a carriage equipped with a magnetic head, and reference numeral 4 is a control circuit for controlling these operations based on a command from the host side. Further, 6 and 7 are a motor and a control circuit constituting an autoloading mechanism, and sensors 1 and 2 for detecting the position of the magnetic disk moving by the autoloading are 8 and 9, respectively. In the insertion operation, the sensor 1 detects that half the magnetic disk has been inserted in the device, the drive for insertion is automatically performed, and the sensor 2 completely detects the setting of the magnetic disk and the operation is completed. Become. Regarding the discharging operation, the control circuit starts auto loading by the discharging command from 10.
Sensor 2 The change in sensor 1 is detected, the magnetic disk is ejected from the device by about half, and the operation ends. The sensor 2 is a sensor that detects that the magnetic disk is at a position where recording / reproducing is possible.

FIG. 2 shows a control circuit diagram of the autoloading of the present invention, which corresponds to 7 in FIG.

First, the discharging operation will be explained. When the command EJECT is input to the D-type flip-flop (hereinafter referred to as FF) 11 and the device is in the selected state and the data input DS is at "H" level, FF
11 is set. As a result, FF20 is triggered and the output of 20 becomes "H", and AU goes through N0R gate and 21,23.
The TO signal is output at "H".

AUTO is for turning the drive motor of auto loading, and while AUTO is "H", the auto loading mechanism works and the magnetic disk is ejected. Due to the discharge, the sensor 2 becomes the detection state, and the “L” signal of the output INSERT is the OR gates 14 and 12.
FF11 and FF20 are changed via, and AUTO is returned to "L". The above is a normal case, but if INSERT remains at the “H” level and the output of the inverter 15 remains at the “L”, FF20 cannot be set forever and there is a risk that AUTO remains at the “H”. This can happen when the magnetic disk is being held by hand when it is about to be ejected, or when something gets caught and gets caught in the middle. Reference numeral 18 is a counter that functions as a timer, and after 21 has become "L", the reset is released and the clock φ starts to be counted, and the signal C becomes "H" after a lapse of a fixed time. At the same time, the operation of the OR gate 17 stops the clock input and the output remains held. Although the set time of 18 is sufficiently longer than the time to normally finish the discharging operation of autoloading, if the above-mentioned discharging operation does not work properly, 18 causes signal C to reset FF11,20 via 14 and 21 and terminate abnormally. Becomes Next, the insertion operation will be described. With the magnetic disk half inserted in the device, the INSERT signal goes to "H", the output of the inverter 15 which is its inverted signal, and the inverter 1 of the CIN signal.
When the inverted signal by 3 is input to the exclusive OR gate 22 and the signal b becomes "H", AUTO is activated via 21 and 23. In other words, while CIN is "L" and INSERT is "H", the autoloading operation is performed, the magnetic disk with CIN "H" is completely set in the device, and the autoloading is completed. If CIN does not become "H" indefinitely under abnormal conditions, the signal C stops the AUTO signal at the gate 23 by the same timers 18 and 17 as the above-mentioned discharge, and the protection operation is performed.

Further, the output CIN from the sensor is indispensable to show the existence of the magnetic disk in the device regardless of the auto loading mechanism. By using this as an element of the auto loading mechanism, the sensor can be shared. ing.

Further, each signal input to the OR gate 16 resets the FF 11 via 14 and 21, so that the EJECT signal is not received. WR of each signal indicates that writing is in progress, and prevents data from being erased by moving the magnetic disk during writing operation. SEEK indicates that the magnetic head is moved by the step motor, and prevents the power consumption of the step motor and the power consumption of the autoloading from being superposed and resulting in a large power consumption. RISE indicates the start-up of the spindle motor and usually has a capacity of 0.5 seconds or less. Since particularly large power consumption is required at the time of starting the spindle motor, the power consumption should not be further increased by the auto loading operation. The AC signal in the figure is a reset signal at power-on.

FIG. 3 is a timing chart of the autoloading of the present invention, which shows the normal operation in FIG.

At the time of insertion, a signal b is output from INSERT being "H" to CIN being "H", and AUTO is set to "H". When discharging, AUTO is set to "H" until a becomes "H" due to the rising edge of the EJECT signal and INSERT falls to "L". C is still "L" and timer output is not yet reached.

FIG. 4 is a timing chart of the autoloading of the present invention, which shows the abnormal operation in FIG.

FIG. 4 (a) shows the case of an abnormality during ejection. Since the INSERT signal is always "H", the output C of the dimer is generated and a and AUTO are returned to "L".

Similarly, FIG. 4 (a) shows the recovery operation at the time of abnormality, which is the case of insertion. When the signal INSERT goes to "H", the autoloading operation starts, but if b based on the CIN signal never goes to "L", the timer works and the AUTO output returns to "L".

FIG. 5 shows another embodiment of the autoloading control circuit.

Unlike FIG. 2, the timer for controlling the autoloading stop at the time of abnormality is changed from a digital circuit counter to a monostable multivibrator. 21 has its output connected to the negative trigger input (-TRG) of the multivibrator 24 and forms the AUTO output. The resistor 25 and the capacitor 26 make up the set time width of the timer.

Even if the 21 outputs continue to be at the “L” level, AUTO disappears after a certain period of time and compensation is provided in the event of an abnormality. The circuit shown in FIG. 2 is all composed of digital logic circuits and can be easily made into an LSI. However, when the circuit is composed of individual parts, the circuit shown in FIG.

(Effects of the Invention) As described above, according to the present invention, it is possible to realize an autoloading mechanism that effectively uses an internal sensor. Furthermore, it is possible to prevent damage to the magnetic disk or the magnetic disk device and shorten the service life due to unforeseen circumstances, erroneous operation or malfunction due to noise, etc. It can also be prevented from being lost.

[Brief description of drawings]

FIG. 1 is a block diagram of a magnetic disk device according to an embodiment of the present invention, FIG. 2 is a control circuit diagram of the auto loading of the present invention, and FIG. 3 is a timing chart showing the auto loading operation of the present invention. 4 (a) and 4 (b) are timing charts of the autoloading operation of the present invention. FIG. 4 (a) shows a case of recovery from an abnormality at the time of ejection and FIG. 4 (b) shows a case of recovery from an abnormality at insertion. FIG. 5 is a diagram of an autoloading control circuit according to another embodiment of the present invention. 1 …… Spindle motor, 2 …… Magnetic head, 5 …… Step motor, 6 …… Loading motor, 7 …… Auto loading control circuit, 8 …… Sensor 1,9 …… Sensor 2, EJECT ……
Ejection command, CIN ... magnetic disk setting end signal, INSERT ... magnetic disk insertion detection signal, AUTO ... auto loading drive signal, 24 ... monostable multivibrator.

Claims (1)

[Claims] 1. A magnetic head for recording / reproducing data on / from a replaceable magnetic disk, a first sensor for detecting insertion of the magnetic disk into an apparatus, and a position for recording / reproducing data on the magnetic disk. A second sensor for detecting that the magnetic disk is present, a control means for controlling the recording / reproducing operation based on the signal of the second sensor, and an automatic operation for electrically inserting and ejecting the magnetic disk. In a magnetic disk device having a loading mechanism, when the magnetic disk is inserted, the first sensor starts driving the auto-loading mechanism based on a signal detecting the magnetic disk, and the second sensor causes the magnetic sensor to start driving. The driving of the auto-loading mechanism is terminated based on the signal that detects the disk, and within a fixed time after the first sensor detects the magnetic disk. A means for stopping the driving of the auto-loading mechanism when the second sensor does not detect the magnetic disk, and a predetermined time period after the second sensor detects the ejection of the magnetic disk when the magnetic disk is ejected. A magnetic disk device, characterized in that it has means for stopping the drive of the auto-loading mechanism when the first sensor does not detect the ejection of the magnetic disk.