JPH0124743Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cassette-type cleaning and degaussing device for cleaning and demagnetizing magnetic heads of tape recorders, etc., in which a switch operation button for opening and closing the excitation circuit of the degaussing head is mounted on the outer surface of the cassette. By providing this, the excitation circuit can be opened as appropriate to perform only cleaning of the magnetic head.

Magnetic heads for recording and playback in tape recorders, etc.
During long-term use, recording and playback characteristics deteriorate due to magnetization and dust adhesion, and therefore it is necessary to periodically demagnetize and clean the magnetic head. For this reason, a degaussing device is built into a cassette of the same size and shape as various cassettes such as the well-known Phillips compact cassette and 8-track cassette, and when the cassette is set on the deck and the play button is pressed, the magnetic head on the deck side A cassette type demagnetizer, a dry type demagnetizer, a wet type demagnetizer, a dry type demagnetizer, a dry type demagnetizer, a wet type demagnetizer, etc., which enter the cassette and hit the degaussing head constituting the demagnetizer, and in that state, generate an alternating gradually decreasing magnetic field in the demagnetizer head to erase the magnetization of the magnetic head. When the cleaning tape is loaded into the cassette, the cassette is set on the deck, and the play button is pressed, the magnetic head enters the cassette and comes into contact with the tape, and in this state the tape feeding device on the deck side is activated. A cassette-type cleaning device has already been put into practice that cleans and removes dust adhering to a magnetic head by driving the tape to slide along the front surface of the magnetic head.

By the way, it is conceivable to incorporate the degaussing device and the cleaning device in the same cassette so that the magnetic head can be degaussed and cleaned at the same time, but in this case, both the degaussing device and the cleaning device can be operated by pressing the play button. Since the magnetic head automatically starts driving when it enters the cassette, cleaning and demagnetization of the magnetic head are always performed simultaneously. However, since cleaning and demagnetizing the magnetic head have very different work purposes, they should not necessarily be performed at the same time. Instead, the degaussing device is stopped and only the cleaning device is driven, and only the cleaning work is performed. There are times when you want to. In particular, this type of degaussing device
Generally, a primary battery is used as a power source for the degaussing device, so if the device is driven unnecessarily, the primary battery will be wasted and its discharge will be completed prematurely.From this point of view as well, the drive of the degaussing device can be stopped at will. It is desirable to be able to do so.

Therefore, the present invention has been devised in consideration of the above points, and is a cassette-type cleaning demagnetizer comprising a cleaning tape placed in a cassette, a degaussing head and an excitation circuit for driving the demagnetizing head. In the apparatus, an operation button for a changeover switch for opening and closing the excitation circuit is provided on the outer surface of the cassette, and thereby the magnetic head can be cleaned and demagnetized at the same time, and the operation button By operating the excitation circuit and opening the excitation circuit, the drive of the degaussing device is stopped and only cleaning of the magnetic head can be performed. Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 is a perspective view of a cassette-type cleaning and degaussing device according to the present invention, and Fig. 2 is a plan view of the same. A feed reel 2 and a take-up reel 3 are rotatably disposed on the holder, and a dry cleaning tape 4 is wound around both reels 2 and 3. Numerals 5, 6, and 6 are a magnetic head insertion port and a pinch roller insertion port provided on the front side of the cassette 1, and the tape 4 is attached to guide rollers 7, 7 rotatably mounted on both sides of the front side of the cassette 1. The tape is adjusted along the magnetic head and is fed along each of the above-mentioned insertion ports 5, 6, and 6. At this time, the magnetic head slides into contact with the front surface of the magnetic head 8 inserted from the magnetic head insertion port 5, and is attached to the magnetic head 8. Clean and remove dust. 9 is a pinch roller.

Reference numeral 10 denotes a demagnetizing head, which is provided adjacent to the magnetic head insertion slot 5, and whose back surface is supported by wire springs 11 fixed at both ends to the cassette 1 so as to be able to move forward and backward. 12 is a micro switch, and when the magnetic head 8 is inserted through the insertion port 5, the degaussing head 10 is pushed by the magnetic head 8 and retreats against the wire spring 11, and the micro switch 12
The lever 12a is pressed in by the wire spring 11, the micro switch 12 is activated, and the excitation circuit wired on the rear excitation circuit board 13 is driven to generate an alternating gradually decreasing magnetic field in the degaussing head 10, and the magnetic head 8
This is to erase the magnetization of. Reference numeral 14 designates a power source battery for the excitation circuit, and reference numerals 15 and 15 designate capstan insertion ports formed on both upper and lower surfaces of the cassette 1, which correspond to the pinch roller insertion port 6.

Reference numeral 16a denotes an operation button for a changeover switch provided approximately at the center of the outer surface of the cassette 1, and is connected to the excitation circuit of the excitation circuit board 13.

FIG. 3 shows the excitation circuit wired on the excitation circuit board 13, in which 14 is the power supply battery, 1
Reference numeral 6 designates a changeover switch that opens and closes the excitation circuit in conjunction with the operation button 16a, and 12 designates the microswitch described above. 20 is a DC booster circuit, which includes a resistor 21, capacitors 22, 23, coils 24, 2
5, transistors 26, 27 and diode 2
8, etc., and boosts the terminal voltage of the power supply battery 14.

30 is a display circuit, which is composed of a light emitting element 31, a switching transistor 32, a resistor 33, etc., and 40 is a switching circuit, which is composed of switching transistors 41, 42 and resistors 43, 44, 45. , each circuit 30,
40 is connected to the output stage of the DC booster circuit 20. Reference numeral 50 denotes a constant voltage circuit connected to the switching circuit 40, which includes a constant voltage element 51 such as a Zener diode and a resistor 52 for detecting a constant voltage level.
3 and 54, and the resistor 54 on the low potential side also serves as a resistor for limiting the current of the booster circuit 20.

60 is a large capacity capacitor connected in parallel to both ends of the constant voltage circuit 50; 70 is an oscillation circuit driven by the accumulated charge of this capacitor 60;
3, 74, output transistors 75, 76, etc., and is connected to the degaussing head 10, which consists of an excitation coil 17, a capacitor 18, etc.

The collector pole of the switching transistor 42 is directly connected to each emitter pole of the output transistors 75 and 76 in the oscillation circuit 70, so that the switching transistor 42 forms a closed loop between the capacitor 60 and the oscillation circuit 70. It is configured as a switching transistor for

This device has the above-mentioned configuration, and its operation will be explained next.

When cleaning and demagnetizing the magnetic head 8 of the deck (not shown), slide the operating button 16a to the solid line position in Figure 2 to close the selector switch 16, then set the cassette 1 on the deck and press the play button. Press. Then, the magnetic head 8 on the deck side is inserted into the cassette 1 from the magnetic head insertion slot 5 on the front of the cassette 1.
When the deck enters the deck and its front surface comes into contact with the cleaning tape 4, the motor built into the deck is activated, the feed reel 2 and take-up reel 3 begin to rotate, and the cleaning tape 4 starts to be fed to the magnetic head 8. The front will be cleaned. When the magnetic head 8 enters the cassette 1 from the magnetic head insertion port 5, the demagnetized head 1 held by the wire spring 11 is inserted into the cassette 1.
0 is pushed back by the magnetic head 8, and the lever 12a of the micro switch 12 is pressed and closed by the wire spring 11, so that the micro switch 12 is operated.
When both the switches 16 and 12 are turned on in this manner, the terminal voltage of the power supply battery 14 is changed to the booster circuit 2.
When the output voltage of the booster circuit 20 is applied to the switching circuit 40, the switching transistor 41 becomes conductive and charging of the capacitor 60 is started.

When the capacitor 60 is charged to a predetermined voltage, a reverse current rapidly flows through the constant voltage element 51, the terminal voltage of the level detection resistor 52 rises, the switching transistors 32 and 42 become conductive, and the light emitting element becomes conductive. 31 emits light to indicate that it is being demagnetized, and at the same time, the switching transistor 41 is cut off and the capacitor 6 is removed from the booster circuit 20.
The voltage application to 0 is stopped. Further, the voltage of the voltage dividing resistor 54 of the level detection resistor 52 is applied to the base pole of the transistor 27 of the booster circuit 20 to limit the current of the booster circuit 20, and the light emitting element 31 is driven at a relatively constant voltage. Emits light.

On the other hand, when the switching transistor 42 becomes conductive, a closed loop is formed between the capacitor 60 and the oscillation circuit 70, and the charge accumulated in the capacitor 60 flows to the oscillation circuit 70, so that the oscillation circuit 70 is driven. Therefore, an alternating magnetic field is generated in the degaussing head 10, which gradually decreases over time as the capacitor 60 discharges, and the magnetization of the magnetic head 8 is eliminated. As described above, when the operation button 16a is turned to the side that closes the excitation circuit, the main cassette 1 is set on the deck, and the play button is pressed, both cleaning and demagnetization of the magnetic head 8 are performed.

Also, the drive of the excitation circuit is stopped and the magnetic head 8
If you only want to clean the
After opening the selector switch 16 by sliding the switch 6a toward the position indicated by the chain line in FIG. 2, the book cassette 1 is set on the deck and the play button is pressed. Then, the tape 4 is fed and the magnetic head 8 is cleaned in the same way as described above, but since the excitation circuit is open, it is not driven, and therefore the magnetic head 8 is not demagnetized.

4 to 6 show another embodiment of the present invention, in which reference numeral 80 is an operation button for the changeover switch 16 provided approximately in the center of the outer surface of a cassette 81 similar to the cassette 1 described above. , is slidably mounted in a rectangular recess 82 formed in the upper plate of the cassette 81. That is, the main operation button 80 is mounted so that its rear end can freely slide along a guide groove 83 recessed along one side periphery of the recess 82.
The excitation circuit of the excitation circuit board 13 is opened and closed by placing a fingertip on the uneven outer surface 80a exposed from the recess 82 of the switch button 80 and sliding it laterally. Further, on one side of the bottom surface 82a of the recess 82, the characters "cleaning" and "demagnetizing" are formed. Reference numeral 84 is a degaussing confirmation window opened adjacent to the front of each character in the recess 82, and the light emitting element 31 is disposed below the window 84. The operation button 80 has a cassette 81
A projecting piece 80b extends from the lower surface of the upper plate, and the characters "cleaning" are formed on the projecting piece 80b.

In this configuration, when cleaning and demagnetizing the magnetic head 8, by sliding the operation button 80 to the position a in FIG. 6, the changeover switch 16 is closed, the excitation circuit is driven, and the magnetic head 8 is Cleaning and demagnetization are performed. In this case, the characters "Cleaning" and "Demagnetizing" formed on one side of the bottom surface 82a are exposed, and the light emission from the light emitting element 31 is visible through the window 84, but the characters "Cleaning" on the protrusion 80b are visible. It is hidden below the upper plate of the cassette 81 and cannot be seen from the outside, thus indicating that the magnetic head 8 is to be cleaned and demagnetized.

When only cleaning the magnetic head 8, slide the operation button 80 to the side (Fig. 6b).
reference). In this state, the changeover switch 16 is opened and only the cleaning of the magnetic head 8 is performed. In this case, the protruding piece 80b of the operation button 80 slides up to above the window 4 and closes the window 84, hiding the light emitting element 31 and exposing the characters "cleaning" formed on the top surface, and also exposing the word "cleaning" formed on the bottom surface 82a. The characters "cleaning" and "demagnetizing" are hidden below the operation button 80, thus indicating that only cleaning of the magnetic head 8 is to be performed. By devising the structure of the operation buttons and the like in this manner, the device according to the present invention becomes more user-friendly.

FIG. 7 shows still another embodiment of the present invention, in which an operation button 9 is provided on the outer surface of the cassette 91.
A cleaning confirmation window 92 and a degaussing confirmation window 93 are provided in front of the operation button 90, and below each window 92, 93, a light emitting element 94 for indicating cleaning and a light emitting element 94 for indicating demagnetization are provided. A publishing element 95 is provided respectively. Figure 8 shows cassette 91
This figure shows an excitation circuit wired on an excitation circuit board built into the excitation circuit, and the excitation circuit includes the above-mentioned cleaning display light-emitting element 94 and the above-mentioned degaussing display light-emitting element 95.
are arranged in parallel, and in place of the changeover switch 16, a changeover switch 96 is provided between the positive line between both the light emitting elements 94 and 95, which opens and closes by operating the operation button 90. This is different from the excitation circuit of the first embodiment.

In the above configuration, when the operation button 90 is slid to the left, the changeover switch 96 is opened and the light emitting element 95 is turned off. Furthermore, when the operation button 90 is slid to the right, the changeover switch 96 is closed and the light emitting element 95 is turned on. Therefore, by visually checking whether the light emitting element 95 is turned off or turned on through the window 93, it is possible to confirm whether or not the magnetic head 8 is being demagnetized. Although the above embodiments have all been explained using the dry cleaning tape 4 as an example, a wet cleaning tape may be used in place of the dry cleaning tape 4, and it is also applicable to micro cassettes. be.

As explained above, the cassette type cleaning and degaussing device according to the present invention includes a cleaning tape 4 placed in the cassette 1, a degaussing head 10, and an excitation circuit for the degaussing head 10. Since the operation button 16a of the changeover switch 16 for opening and closing the excitation circuit is provided on the outer surface of the excitation circuit, it is possible to clean and demagnetize the magnetic head 8 at the same time, and also to clean the magnetic head 8 only. This has advantages such as preventing wasteful consumption of the power source battery 14.

[Brief explanation of the drawing]

The figure shows an embodiment of the present invention.
The figure is a perspective view of a cassette-type cleaning and degaussing device according to the present invention, FIG. 2 is a plan view of the same, FIG. 3 is a degaussing circuit diagram, FIG. Figures 6a and b are plan views of the same main parts, Figure 7 is a cross-sectional view of the same main parts,
The figure is a perspective view of still another embodiment of the present invention, and FIG. 8 is a degaussing circuit diagram. 1,81,91...cassette, 4...cleaning tape, 10...demagnetizing head, 16,96...
...Selector switch, 16a, 80, 90...operation button.

Claims (1)

[Scope of utility model registration request] A cleaning tape 4 is placed in the cassette 1, and a demagnetizing head 10 and an excitation circuit for the demagnetizing head 10 are arranged.
A cassette-type cleaning and degaussing device in which an operating button 16a of a changeover switch 16 for opening and closing the excitation circuit is provided on the outer surface of the device.