KR920001132B1 - De - magnetization device for vtr - Google Patents

Abstract

The magnetic device prevents undesirable magnetic effects such as magnetization of a magnetic head, a capstan and a guide in a cassette deck. The magnetic device includes: an audio recording switching section (A); a bias level selection switching section (B); a bias oscillating section (C); and a magnetic head section. Further, a magnetic device switching section (D), a magnetic device switch control section (F), and a magnetic device section (G) are disposed in such a manner that the output of the bias oscillating section can be used as the oscillating signals for the magnetic device. The magnetic device section converts the oscillating signals into magnetic fields, the magnetic device section being installed in a detachable form.

Description

Deck Device

Figure 1a, b is a schematic structural diagram showing a conventional rod-type and cassette-type device device.

2 is a block diagram of the present invention.

3 is a detailed circuit diagram of the present invention.

4A and 4B are schematic structural diagrams showing rod-type and cassette-type device devices in the present invention.

* Explanation of symbols for the main parts of the drawings

A: recording switch part b: bias level selector switch part

C: bias oscillation part d: device operation switch part

ㅁ: magnetic head part ㅂ: element operation switch control part

S: element part 10: metal material for magnetic induction

11: Coil part for element 12: Vinyl cap for protection

13: PLUG 14: contact for input of oscillation output for device

15: Device operation control contact SW ₁ : Recording switch

SW ₂ : Bias Level Selection Switch

SW _3-1 , SW _3-2 , SW _3-3 : Device Operation Switch

H ₁ : Magnetic head for recording H ₂ : Magnetic head for erasing

MIX ₁ , MIX ₂ : Synthesizer C ₁ , C ₆ : Condenser

R ₁ , R ₄ : Resistor Ry ₁ : Relay

T ₁ : bias oscillation coil Q ₁ : bias oscillation transistor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for a deck, and to prevent the reduction of recording and playback characteristics caused by metal parts such as magnetic headings, capstans, and guides inside the deck. It is.

As a conventional device, there are separate devices of a rod type and a cassette type as shown in Figs. 1A and 1B. However, the former rod type (Fig. 1a) element has a heavy weight and is inconvenient in use because the power supply circuit B and the oscillation circuit C are installed inside the device, and the latter cassette type is used. In the case of FIG. 1B, the inconvenience of having to periodically change the battery G is a structure in which the element portion D contacts only the head, and thus there is a problem in that the element is not made in other metal parts such as a capstan. . In addition, both have a problem in that the burden is increased because the user must purchase separately from the deck.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and by using a recording oscillation circuit mounted inside the deck as an element oscillator, the output is applied to a separate element portion to realize a lighter weight. In addition to the convenience of the cassette type, as well as the magnetic head as well as the capstan, the guide and the like to be able to simultaneously, as described in detail below in accordance with the accompanying drawings.

As shown in the block diagram of the present invention shown in FIG. 2, a device comprising a recording switch unit 7, a bias level selection switch unit (B), a bias oscillator unit (C), and a magnetic head unit (ㅁ) built into the deck. In Fig. 3, an element operation switch d, an element operation switch control section and an element section are additionally provided, the detailed circuit of which is shown in FIG. Referring to Figure 3 in more detail the rotational operation of Figure 2 as follows.

)로부터 각각 접속되어 있는 상태가 된다.In FIG. 3, first small, so if it does not operate as a magnetic is because element section (M ₁₎ the connector (CN ₁₎ are not connected by a (CN ₁₎ state, the relay (Ry ₁₎ is not being driven Device operation switch (SW _3-1 ) (SW _3-2 ) (SW _3-3 ) is a contact terminal (

Are connected to each other.

In this state, when the recording switch SW ₁ is turned on, the B ⁺ voltage is applied to the middle tap coil terminal b of the bias oscillation coil T ₁ according to the position of the selection contact point of the bias level selection switch SW ₂ . The transistor Q ₁ . Oscillation starts as a magnitude proportional to the voltage applied at the bias oscillation stage consisting of the resistors R ₃ (R ₄ ) and the capacitors C ₂ (C ₃ ) (C ₄ ).

This oscillation signal is oscillating at a resonance frequency due to the inductance of the secondary side of the step-up by the first and second turns ratio between the primary side of an oscillation coil (T ₁₎ and a capacitor (C ₅₎ and the oscillating coil (T ₁₎ is output . The oscillation signal is synthesized by the recording signal and the synthesizer (MIX ₁ ) through the condenser (C ₆ ) connected to the terminal (d) of the oscillation coil (T ₁ ) and applied to the recording head (H ₁ ). It is recorded on (not shown). In addition, the oscillation signal is applied to the erasing head H ₂ through the terminal e of the oscillation coil T ₁ to erase the signal recorded on the magnetic tape.

)로 각각 접속된다.On the other hand, in the case of operating as an element device, since the element portion M _{1 is} connected to the connectors CN ₁ and CN ₂ , the relay Ry ₁ is driven accordingly, so that the element operation switch (SW _{3 −). 1} ) (SW _3-2 ) (SW _3-3 ) is the contact terminal (

Are connected respectively.

In this state, if the recording switch (SW ₁ ) is turned "on", the B + voltage becomes the oscillation coil in the oscillation part through the recording switch (SW ₁ ) and the element operation switch (SW _3-1 ) and the reverse surge prevention diode (D ₁ ). The oscillation starts because it is added to (T ₁ ).

This oscillation signal is applied to the element portion M ₁ through the element operation switch SW _3-3 and the connector CN ₁ and CN ₂ . The element portion M ₁ can be configured to have the same structure as the electromagnet wound around the metal rod. When the oscillation signal is applied to the coil, the magnetic field of the metal rod changes.

That is, when the metal material is brought close to the device portion M ₁ , a magnetic induction phenomenon occurs, and the magnetic field of the metal material is changed on the magnetization curve. At this time, if the magnitude of the magnetic field is gradually reduced, the internal residual magnetic field of the metal material converges at the origin of the magnetization curve, and the residual magnetic field is lost. By using this write operation by contacting the element section (M ₁₎ in the magnetized metal part in the deck recording heads, capstans, guides, thereby removing the magnetic phenomenon.

Here, the condenser C ₁ is for causing the output of the oscillator to be gradually attenuated when the recording switch SW ₁ is turned off so that the outflow magnetic field at the element portion is gradually attenuated.

On the other hand, FIG. 4 schematically shows the rod-type and cassette-type device arrangements in the present invention, so that the rod-type shown in FIG. The insert is to be used to hold the device portion by hand, the protective vinyl cap 12 of the front end is to prevent the metal portion of the deck is damaged due to the metal rod of the device portion abuts on the metal portion of the deck.

An oscillation output contact point 14 and an element operation control contact point 15 are formed at the upper end of the tape insert of the cassette-type deck shown in FIG. 4B, and these contact points 14 and 15 contact the upper end of the cassette-type element part. By forming a terminal to be in a state to insert the device portion on the deck and the recording switch (SW ₁ ) is to be formed to erase the magnetic head and metal parts such as capstan, guide at the same time.

As described above, according to the present invention, by using the recording oscillation circuit mounted inside the conventional deck as an element oscillator and applying the output thereof to a separate element, the composition of the element is reduced in weight and convenience for use. In addition to providing a cassette type, which has been caused by a conventional problem, not only the magnetic head, but also the capstan and guided elements can be simultaneously operated.

Claims (3)

In the device device composed of a recording switch (a), a bias level selection switch (b), a bias oscillator (c) and a magnetic head (ㅁ) built in the deck, the bias level selection switch (b), bias An element oscillation signal for output of the bias oscillator (c) inside the deck by connecting an element operation switch (L), an element operation switch controller (ㅂ), and an element portion (G) between the oscillation section (c) and the magnetic head section (ㅁ). It is used as, and characterized in that the element portion (S) for converting the oscillation signal into a magnetic field can be detached from the outside. According to claim 1, wherein the element portion (S) is a metal portion 10 for removing the internal residual magnetic field by contacting the element coil portion 11 and a metal material such as a magnetic head, capstan and guide therein. Deck element device, characterized in that configured to include a cassette. The metal part 10 of claim 1, wherein the device part is in contact with a metal part such as a coil part 11 and a magnetic head, a capstan, a guide, and the like to remove an internal residual magnetic field. And a protective vinyl cap 12 formed at the front end of the coil part 11 for the device, and a rod type having a plug 13 having an electrical connection to the coil part 11 for the device. Deck device device characterized in that.

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