JPS6050614A - Method and apparatus for cleaning head - Google Patents

Abstract

PURPOSE:To execute cleaning efficiently and precisely by decelerating the rotation of a cleaning member lower than the rotation at the charge of a recording medium when the cleaning member is charged. CONSTITUTION:The titled apparatus is constituted of a motor servo device A, a control device B, a cleaning mode display device C, and a power supply circuit D. When a recording medium such as a magnetic sheet is charged, the motor 6 rotates the recording medium in the normal recording/reproducing mode to record or reproduce a signal. At the charge of the cleaning member such as a cleaning sheet 2' the rotation of the cleaning member is controlled so as to be decelerated lower than the rotation at the recording/reproducing mode.

Description

[Detailed Description of the Invention] (Technical Field) The invention of this application relates to a method and device for cleaning a recording or [1] recording head, and particularly to a method and device for efficiently and reliably cleaning a recording or [1] head. Regarding.

(Prior art) In a device that performs recording or reproducing of a magnetic field +1φ using a recording medium such as a rotating magnetic sheet, the recording or reproducing characteristics may deteriorate if the area facing the recording medium of the recording or reproducing heel 1 is dirty with chips or dust. descend. Therefore, in order to remove such stains, for example, a method of cleaning the surface of the head with a bath agent has been used.

However, in a video signal recording or reproducing apparatus, the -\rad is constructed in an extremely precise manner, and therefore, the above-mentioned cleaning method is likely to cause an accident that damages the head. Furthermore, in rotary magnetic sheet recorders and the like, the head is installed in many places that are difficult to reach, so it is often difficult to apply the above method.

Therefore, a method has been proposed in which a so-called cleaning sheet or the like to which a cleaning wrap material is attached is loaded and the head is cleaned by rotating the cleaning sheet or the like in the same manner as during normal recording or reproduction.

By the way, in a recording or reproducing device that handles video signals, the differential speed between the rotating sheet and the head is large, so as will be explained in detail later, an air layer (
AtrFi]m) is formed, and the presence of this air layer makes it difficult to remove dirt from the surface of the head. Therefore, when using the above cleaning method, it is necessary to take measures to eliminate or reduce the influence of the above air layer.

Furthermore, it is desirable that the cleaning sheet and the like described above have the same form as the recording sheet because they can use a common rotating means, but if they have the same form, it will be easy to It is necessary to identify the two by appropriate means, and to operate means for removing or reducing the influence of the air layer when a cleaning sheet or the like is loaded.

(Purpose) The first invention of this application is to arrange a recording or reproducing device facing a cleaning member provided with a cleaning member, and to rotate the latter by a recording medium drive device to perform recording or reproducing. 〃This is a method of cleaning the head as described above, when the cleaning member is loaded, the rotation speed of the cleaning portion A1 is made slower than the rotation of the recording medium during recording or reproduction, thereby efficiently cleaning the head. The purpose is to provide a method for cleaning the area.

The second invention is an apparatus for cleaning the recording or (f), ++T raw head by arranging the recording or reproducing head to face a cleaning member provided with a cleaning member, and rotating the latter by a recording medium drive device. An object of the present invention is to provide an apparatus in which, when the cleaning member is loaded, the rotation of the cleaning member is automatically made slower than the rotation of the recording medium during recording or reproduction.

(Explanation based on Examples) The methods and means taken in the invention of this application to achieve the above object will be exemplified and explained below using Examples shown in the drawings. In this specification, the term "recording or reproducing head" refers to a recording or reproducing head such as a magnetic head, an optical head, or a capacitive head, and the term "recording medium" refers to a recording or reproducing head such as a magnetic head, an optical head, or a capacitive head. A recording medium on which recording or reproduction is performed may be in the form of a sheet or a disk, and the recording tracks formed on the recording medium may be either concentric or spiral.

The following explanation assumes that the recording or reproducing head is a magnetic head.
Regarding an example in which the recording medium is a magnetic sheet, the relative movement between the head and the rotary sheet, a specific example of the recording medium applied to the invention of this application, a specific example of the cleaning member applied to the invention of this application, and this application The embodiments of the head cleaning method and apparatus of the invention will be described in order.

(Relative Movement between Head and Rotating Sheet) The main feature of the invention of this application is to make the rotation of the cleaning member slower than the rotation of the recording medium during recording or reproduction. Prior to explaining the specific means, we will discuss a sheet-shaped cleaning member provided with a head and a cleaning member. l: '! ', the relative movement between the fH medium and the rotating sheet will be explained. Generally, the thickness of the air layer between the head and the rotating sheet is determined by the shape of the head, the viscosity of the air, the rigidity of the sheet, and the relative speed between them. When lowered, the thickness of the air layer decreases. For example, the air layer I'7-
”, and the relative velocity is V, then h = c-Vn(n
) 1 + c is a constant).

The invention of this application attempts to efficiently remove dirt on the surface of the head by lowering this relative speed to an appropriate range and rotating the cleaning member in a state where the head and the cleaning layer are in contact with each other. However, as to how much the relative speed should be reduced, this relative speed is the relative speed between the head and the member provided with the cleaning material, so for the rotating seat, its circumferential speed is This is a problem that depends on the angular velocity of rotation of the sheet and the diameter of the sheet, as well as on the various factors mentioned above, will vary with the design of the device, and is not limited to any particular critical value. However, according to the actual time of the inventors, the distance between the disk and the traveling recording medium during recording or reproduction, that is, the thickness of the air layer is 250 nm and 8 degrees, and in order to carry out the invention of this application, It is possible to reduce this interval to one-half or less.

(Specific examples of recording media applied to the invention of this application) (Figures 1 and 2) Figure 1 shows a magnetic sheet, which is an example of a recording medium applied to the invention of this application, stored in a cassette. FIG. 2 is an enlarged sectional view of the phase detection device for detecting the rotation of the recording medium.

In FIG. 1, 1 is a cassette in which a magnetic sheet 2 is stored, 3 is a center core to which the magnetic sheet 2 is fixed by means such as adhesive, 4 is implanted in the center core 3,
A magnetic pin 1'1 passes through the core 3, 5 is a magnetic head 14
This is an opening for bringing the magnetic sheath 12 into contact with the magnetic sheath 12.

FIG. 2 is an enlarged sectional view of the phase detection device including the center core 3, with the cassette omitted. In the figure, 6 is a sheet rotation motor, which is an example of a recording medium drive device, and 7 is the motor 6! A shaft rotates integrally with the It axis, 8 is a sorting attachment hub fixed to the rotating shaft 7, 9 is a permanent magnet for sheet chucking fixed to the sheet attachment hub as shown in the figure, and the axial direction It is magnetized to. Here, the center core 3 is made of non-magnetic material such as resin, and has an opening in the center that fits into the hub 8, and the magnetic pins 4 are inserted into the holes provided on the outside of this opening. ing.

10 is Sea I-Cha fixed to the center core 3.

A king ring made of magnetic material, ring 10
Due to the action of the magnet 9, the center core 3 is magnetically fixed to the block 8 and rotates integrally with the motor 6. Note that the magnetic pin 4 is fixed to the ring 10 by means such as caulking. A plurality of magnetic pins 4 may be installed, and the chunking ring 10 may be bent.

The magnetic pin 4 extends inside the center core 3 to the opposite surface of the ring 100, and a PG coil 12 made of magnetic material 41 is provided opposite the center core 3, and a PG coil 12 is wound around the PC core 1. , the output is output from the lead wire 13.

In the above configuration, the magnetic flux of the permanent magnet 9 is transferred to the ring 10,
A leakage magnetic flux is formed outside the center core 3 through the magnetic pin 4. As a result, as the center core 3 rotates, P
In G Cocoano, the magnetic flux is maximum when the magnetic pin 4 reaches the opposing position or its vicinity, and decreases as the magnetic bottle 4 moves away. Therefore, the PG coil 12 has a PC
A voltage is generated that is proportional to the temporal change in the magnetic flux passing through the core 1, and the phase of the multi-rotation magnetic sheet 2 is detected by this voltage.
This voltage passes through the lead compression 13 and is used in the device described later.

(Specific example of the cleaning member applied to the invention of this application) (Figs. 3 and 4) Fig. 3 shows an example of the cleaning member applied to the invention of this application in a cassette similar to Fig. 1. FIG. 4 is a plan view of the cassette in the stored state, and an enlarged cross-sectional view showing the state in which the cleaning member and the drive device are connected when this cassette is loaded into the drive device. In the figures, components having substantially the same configuration and function as those shown in Figures 1 and 2 are designated by the same reference numerals.

In these figures, 1' is a rotatable cleaning member, and preferably has at least a base sheet (film) having similar properties to the base sheet (film) of the magnetic sheet 2 described above. One side 2'a (
In FIG. 4, a cleaning wrap material 15 is provided over almost the entire surface (the surface facing the henode 14). Note that the wrapper may be made of the same material as the wrapping material of the cleaning tape in a VTR or the like, and is applied, for example, to the surface of the base sheet. Hereinafter, the 7-tooth 2' provided with the cleaning wrap material 15 will be referred to as a cleaning sheet.

The cleaning sheet 2' is attached to the center core 3' in the same way as the magnetic sheet 2, but the cleaning sheet 2' attached to the center 3' is 2TJ: Magnetic sheet 2.
Similarly, it is stored in the cassette 1', but in this case, the wrap material 15 is applied so that the part 2'a faces the opening 05.

FIG. 4 shows the state in which the center core 3' and the sheet attachment hub 8 are connected when the cassette 1' containing the cleaning sheet 2' is loaded into the drive device. In this case, since no magnetic pin is provided in the center core 3', no rotational phase signal (PC signal) is generated in the PG coil 12 even if the cleaning sheet 2' is rotated.

(Example of the head cleaning method of the invention of this application and its equipment f1) (Figs. 5 to 7) Fig. 5 shows a specific example of an apparatus for carrying out the head cleaning method of the invention of this application, especially its record. This example shows a drive control device for a medium and a cleaning member, and this example shows 20 rotations of a magnetic sheet having a magnetic pin (No. 11, 4 in FIG. This is an example of identifying and controlling the f of the subsequent IS.In other words, when the recorder, for example, the magnetic 7-toe 2, is fully loaded, the motor is rotated in the normal recording/playback mode and the signal is recorded. In addition, V1: performs playback, and when a cleaning member such as the cleaning sheet 2' is loaded, the rotation speed is set at a low speed even in the recording/playback mode.In FIG. 5, A is a motor servo device. , B is a control device, C is a display device for displaying the cleaning mode, and ■) is a power supply circuit.

In the motor servo device A, a frequency signal (FC signal) generated in accordance with the rotation of the sheet rotation mokro is subjected to waveform compensation in the FG signal shaping circuit 2, and inputted to the F-V conversion circuit 22 that converts the frequency into voltage. On the other hand, the rotational phase signal (PG multiplied signal (Fig. 1j6 (a)) generated in the PG coil 12 that detects the rotational phase of the magnetic sheet 2 that is subjected to multiple rotations during sheet rotation is waveform-shaped by the PG signal shaping circuit 23. (the rotation speed of the second motor 6 is set to a predetermined speed (for example, 3.
60 Orpm), and the phase is compared with the reference phase signal Vn, which should be 60 Orpm), and as a result, an error voltage ΔV is generated. The fixed voltage generation circuit 26 sets the rotational speed of the motor 6 to a predetermined low speed (
For example, 900 rpm compared to the normal 3.60 Orpm.
A predetermined voltage .DELTA.V' is generated to make the voltage .DELTA.V'. The switching circuit 27 selects this predetermined voltage Δ■′ and the above-mentioned error voltage Δ■ in response to the control output from the control device B,
This is applied to the F-V conversion circuit 22.

The F-V conversion circuit 22 receives the FG from the FG signal shaping circuit 21.
Converts the number into voltage and connects it to the switching circuit 27.
The control voltage for the motor drive circuit 28 is determined based on the combined voltage, and the
The rotation of the rotary motor 6 is controlled.

:filJ Both devices B control the motor servo device A to change the rotational speed of the sheet rotation motor 6 depending on whether the recording medium 2 or the cleaning member 2' is loaded. The control device 13 is connected to the control input terminal P of the switching circuit 27, and the switching circuit 27 is connected to the control input terminal P of the switching circuit 27, and when the control input to the P i'+:M child is at a high level, the switching circuit 27 is connected to the control input terminal P of the switching circuit 27. Select the output Δ■, and when the control input is low level, the fixed voltage generation circuit 26
is operated to select the output ΔV'.

The npn switching transistor Tr1 of the control device B has its pace connected to the PG signal shaping circuit 23 via the resistor R1.
The collector is connected to the power supply VccK via the resistor R2, and the emitter is grounded. CI is a capacitor that forms a time constant circuit together with the JIE resistor R2, and It is connected in parallel between the collector of the transistor Tri and the ground, and is further connected to the inverting input (~) of the comparator circuit 29. R3 and R4 are five voltage dividing resistors connected to the iA column and cc to 1. Therefore, the connection point is connected to the non-inverting input (+) of the comparator circuit 29,
A base fjp potential Vr is given. The output terminal of the comparator circuit 29 is connected to the power supply VccVC1 and further to the control input (P terminal) of the switching circuit 27 via a sol-up resistor R5.

sl is an operation command switch for the seat rotation motor control, and is connected to the power supply Vcc via a resistor R6, and to the npn switching transistor Tr2 via a resistor R7. The collector of the transistor Tr2 is connected to the output terminal of the comparator circuit 29, as well as to the pull-up resistor R5 and the aforementioned P terminal, and its emitter is grounded.

The display wave #C consists of a sound generator 3o and an oscillator 3 that operates it, and the oscillator 3 is connected to the collector of a pnp switching transistor Tr3, the emitter of the transistor Tr3 is connected to the power supply Vcc, and its base is connected to a resistor. R
8 to the output of the comparator circuit 29. The display device C may be constituted by a visual display device such as a light emitting diode instead of the sound generating device 30.

The power supply circuit supplies power VCC to the control device B, display device C, and other required circuits via the main switch SM.

In the device shown in Fig. 5, the main switch SM is the operation command switch s.
It is linked to 1.

Next, the operation of the apparatus shown in FIG. 5 will be explained. This device connects the PC within a predetermined time after power is supplied to the seat rotation motor 6.
When the PG multiplied signal cannot be obtained at the output (Q terminal) of the signal shaping circuit 23, the rotational speed of the motor 6 is reduced to a low speed. When starting this device, the main switch S
When M and the operation command switch S1 interlocked with this are closed, the supply of 11j:σ. The trunk transistor Tr2 is turned off, and the ratio +1 friend circuit 29 sets the reference potential v to the non-inverting input (+).
Since the output becomes high level due to the input of r, the control I input to the terminal P of the switching circuit 27 becomes the Hatake level, so the output ΔV of the phase comparator circuit 250 is selected, and at the same time, the motor 6 is supplied with power. and start it. The operation of the apparatus shown in FIG. 5 will be explained in detail below. First, (1) When the case no. A signal is obtained, which is waveform-shaped and generated at the terminal Q. The Noculus shown in FIG. 6(b) is periodically applied to the base of the transistor Tri. The transistor Tri is turned off when the voltage shown in FIG. 6(b) is not applied from the Q terminal, and the capacitor C1 is charged via the resistor R2, but the Q
When the above-mentioned pulse is applied from the terminal, it is turned on, the charging voltage of the capacitor C1 is discharged through the transistor Trl itself, and the charging and discharging of the capacitor C1 is reversed.

If the resistor R2 of the time constant circuit, the capacitor CI, and the basic thread potential Vr are appropriately selected, the capacitor C
As shown in FIG. 6(c), the voltage at I does not exceed the reference potential Vr, and therefore, as long as the magnetic sheet 2 is rotating normally, the voltage at is maintained at a high level, and the power supply to the motor 6 is continued.Then, by the action of the servo device A, the rotation of the motor 6 is controlled to the speed of the recording/reproducing mode of 3.60 Orpm, for example. Ru.

(2) On the other hand, when the cassette 1/ that stores the cleaning sheet 2' is loaded, since the sheet core 3' is not provided with a magnetic pin, the motor 6 is energized and the cassette 1/ is activated. However, as shown in Figure 7 (a'), the KPG signal is not obtained, and as shown in Figure 7 (b'), there is no P pulse output at the Q terminal, and the terminal remains at a low level. It is. Therefore, the transistor Tri remains off and the capacitor C1 continues to be charged, and its charging voltage exceeds the base half potential Vr at the short poem r#41 (as shown in Figure C), and the output terminal of the comparator circuit 29 As shown in (d'), the level becomes low at the same time.As a result, in the switching circuit 27 of the servo device A, the output Δ of the fixed voltage generation circuit 26
V' is selected, and the rotational speed of the motor 6 is set to 900, for example.
The speed is reduced to rpm.

Note that ta in FIGS. 6 and 7 indicates the time when the switches SM and SL are closed, and H in FIG. 7 indicates the time when the output of the comparator circuit 29 changes from high level to low level.

(3) In this way, after closing the switches SM and sl, the output of the comparison @ path 2g is changed from a high level to a low level, so that the motor 6 is decelerated, and the cleaning is rotated by the low speed rotation of the motor 6. The p-head 14 is cleaned by the lug material 15 provided on the surface 2'a of the sheet 2', and dust and dirt adhering to its surface are removed. When the cleaning sheet 2' is rotated at low speed in this way, the lug between the head 14 and the sheet 2' is 0#.
The generation of an air layer between the head 14 and the head 15 can be avoided as much as possible, and the head 14 can be cleaned efficiently.

(4) Identification voltage generation circuit 2 by switching circuit 27
When the output No. 6 is selected, the low level potential of the P terminal of the switching circuit 27 is applied to the pace of the transistor 'rr3 via the resistor R8.
is turned on, the oscillator 30 starts, and the sound generator 31
Alternatively, the above-mentioned visual display device indicates that the 78th cleaning of the sieve 14 is being carried out.

As described above, according to the apparatus shown in FIG. 5, the presence or absence of the rotational position signal is determined depending on whether the magnetic sheet 2 or the cleaning sheet 2' is loaded, and it is determined whether the latter is loaded. At this time, the rotation speed of the sheet rotation motor 6 is automatically set to a low speed, so that the head 14 and the wrapping material 1
The generation of an air layer between the head 14 and the head 14 can be avoided, and the head 14 can be cleaned efficiently.

(Effect) According to the first invention of this application, the recording or reproducing head is opposed to the cleaning section provided with the cleaning material, and the cleaning member is rotated by the recording body drive device to record or reproduce the information. When cleaning the head, when the loading of the cleaning member is detected, the rotation of the cleaning member is made slower than when a recording medium is loaded, thereby eliminating or reducing the effect of the air layer mentioned above. Therefore, the recording or reproducing head can be cleaned efficiently and reliably.

According to the second invention, record or tI4 raw head l゛? F
/ facing the cleaning member provided with the scavenger, and
#i) Move the member 9 times + 1 times by the recording medium drive device and
In an apparatus for cleaning a recording or reproducing head, when the cleaning member is loaded, the rotation speed of the cleaning member can be automatically reduced to a low speed.

Furthermore, when using a rotational phase detection means (for example, a magnetic bottle) provided on the recording medium as a rotational signal generation means,
Since this rotational phase detection means should be provided to synchronize the phase of the recorded signal, especially the video signal, with the rotation of the recording medium, it is possible to easily detect the recording medium and the cleaning member without changing the configuration of the recording medium. It is possible to carry out loading identification.

Incidentally, the present applicant first proposed a recording or reproducing head configured to face a member provided with a cleaning material and to perform relative movement between the two to clean the recording or reproducing head. The apparatus includes a detection means for identifying that the member provided with the cleaning material is loaded, and a speed of the relative movement corresponding to the detection means when the detection means identifies that the member is loaded. He proposed a means of slowing down the recording or reproducing speed and a metal fitting device (patent application 1983).
No. 11688, title of invention "Cleaning device for recording or reproducing head"). In comparison, the invention of this application includes a rotation signal generation means in the recording medium itself, and the recording medium and the rotation signal generation means ! -h#f The feature is that it is possible to identify which one of the cleaning members has been loaded, based on the presence or absence of a rotation signal.

[Brief explanation of drawings]

FIG. 1 is a plan view of a state in which a magnetic sheet, which is an example of a recording medium applied to the invention of this application, is housed in a cassette;
FIG. 2 is an enlarged cross-sectional view of the phase detection device for detecting the rotation of the magnetic sort shown in FIG. 1. Is FIG. 3 applicable to the invention of this application? h A plan view of the sweeping part 'IJ stored in the cassette, 4th (1-1-1) part A and the driving device when the sumo wrestlers in Figure 3 are loaded into the driving device. The enlarged Ifjr diagram and the surface 5 diagram showing the combined state with i^i are the recording medium and the ? Figures 6 (a) to d) and Figures 7 (a to d) showing a partial circuit diagram of an example of the drive control device for the +'+'
) is an explanatory diagram of the operation of the apparatus shown in Fig. 5 when a recording medium and a cleaning member are respectively installed. In the figure, 1 and 1' are a cassette, 2 is a magnetic sheet that is a recording medium, 2' is a cleaning member that is a cleaning member, and 3, 3.
' is a center core, 4 is a magnetic pin which is a rotation signal generating means, 6 is a motor, 12 is a PG coil, 14 is a recording or reproducing head, 15 is a raffle, 25 is a phase comparison circuit, 26
is a fixed voltage generation circuit, 27 is a switching circuit, 28 is a motor drive circuit, 29 is a comparison circuit, SM is a main switch,
Sl is an operation command switch for the motor, Tri +
Tr2 r Tr3 is a switching transistor, R2
and CI indicate a resistor and a capacitor constituting a time constant circuit. Figure 1 Child Figure 2

Claims (2)

[Claims] (1) A method of cleaning the recording or reproducing head by arranging the recording or reproducing head to face a cleaning member provided with a cleaning material and rotating this cleaning member by a recording medium drive device, the method comprising generating a rotation signal. identifying which one is loaded: a recording medium provided with a means, or a cleaning member provided with a cleaning groove on at least one side thereof and not provided with a rotation signal generating means, and when the cleaning member is loaded, this cleaning member A recording or reproducing head cleaning method 0 characterized in that the rotation speed of the recording head is reduced to a low speed when the recording medium is loaded. (2) A drive chip 1 which is provided with a recording medium equipped with a rotation signal generating means and a cleaning material on at least one surface thereof, and which is equipped with a rotation signal generating means and rotates any of the cleaning members facing the recording or reproducing head. ) a detection means for identifying whether either the recording medium or the cleaning member is loaded based on the presence or absence of a rotation signal generated by the rotation signal generation means; and a detection means that responds when the cleaning member is loaded. and control means for rotating the cleaning member at a slower speed than when the recording medium is loaded.