KR930002893B1 - Video head auto cleaning device for vtr - Google Patents

Abstract

The device comprises a section (11) for controlling the system with key input, a servo section (12) for outputting motor driving signal by the signal of the system control section (11), a head drum (13) rotated by the motar driving signal, a free amp (14) for amplifying recorded signal to tape, a section (15) for processing image signal from amplified signal of the free amp, automatic cleaning control section (16) for the output of sensing signal from the amp, a section (17) for the output of driving signal from the system control section (11), a head cleaner (18) operated by the driving signal. The automatic cleaning control section (16) includes of an integrator for the amplified signal from the free amp, a sampling and holder for integrated signal, a comparer for output signal of the integrator.

Description

Automatic cleaning head of video tape recorder

1 is a view showing a conventional video head cleaning apparatus, FIG. 1 is a diagram showing a stationary state, and FIG. 1 is a diagram showing an operating state.

2 is a block diagram of an automatic video head cleaning apparatus according to the present invention.

3 is a detailed circuit diagram of an automatic cleaning control unit.

4 is a cross-sectional view of the head cleaner.

4B is a view schematically showing the stop and the operating states of the head cleaner, respectively.

5 is a view showing an operating state of the head cleaner according to the present invention, a is a state in which the head cleaner does not operate.

b is a state in which the head cleaner is in close contact with the head drum.

* Explanation of symbols for main parts of the drawings

11: system control unit 12: servo unit

13: drum assembly 14: preamp

15: image signal processing unit 16: automatic cleaning control unit

17: drive unit 18: head cleaner

21: Integrator 22: Sampling and Holder

23: comparison 31: electromagnet

32: permanent magnet 33: support shaft

34: spring 35: fixed wing

36: cap 37: support

38: cleaner support 39: cleaner

The present invention relates to a video head cleaning apparatus of a video tape recorder, and more particularly, to a video head automatic cleaning apparatus capable of automatically removing foreign substances.

Conventionally, as shown in FIG. 1A, the support 5 is provided on the left or right side of the head drum 1 around the fixed shaft 4 according to the left and right movement of the moving shaft 3 by the solenoid 2. The video head cleaning device was configured such that the head cleaning portion 7 attached to the support 6 provided at the end was in close contact with the head drum 1 and the video head was cleaned by the rotation of the head drum 1.

That is, as shown in FIG. 1B, the solenoid 2 is selected by the user's selection or the like; When the drive power is supplied, the solenoid 2 is operated to move the moving shaft 3 in the direction of the arrow a.

Accordingly, the support 5 is rotated in the direction of the arrow (b) around the fixed shaft 4 so that the head cleaning portion 7 attached to the support 6 is in close contact with the head drum 1.

At the same time, the head drum 1 is rotated to clean the video head. However, since such a conventional video head cleaning apparatus can only be installed at a tape loading portion, cleaning cannot be performed during tape loading, and a peripheral space is required.

In addition, since the shrinking force of the solenoid is directly transmitted through the shaft, the video head and the cleaning part are rubbed, and thus, the head is likely to be damaged and the wear rate is high.

It is an object of the present invention to provide a video head automatic cleaning device suitable for automatically removing foreign matter from a head.

Another object of the present invention is to provide a head cleaner that is in close contact with the head by magnetic repulsive force and is easy to install so that no separate space is required.

Features of the present invention for achieving the above object is a system control unit for controlling the entire system by receiving a key input, a servo unit for outputting a motor drive signal in accordance with the signal of the system control unit, constant speed in accordance with the motor drive signal of the servo unit A pre-amplifier for reading and preamplifying a head drum rotating in a positive phase, a amplification signal processor for processing an amplified signal in the preamplifier as an image signal, and amplified signal in the preamplifier. Video of a video tape recorder comprising an automatic cleaning control unit for sensing and outputting a detection signal, a driving unit for outputting a driving signal by judging the detection signal of the automatic cleaning control unit by the system control unit, and a head cleaner operated according to the driving signal of the driving unit. The head is in the automatic cleaning device.

Another feature of the present invention is an electromagnet in which a magnetic field is induced by applying an electric current, a support shaft in which a permanent magnet opposing the electromagnet is embedded, a spring provided on the outside of the support shaft to closely adhere the permanent magnet to the electromagnet side, and a magnetic field of the electromagnet. Cap with fixed blades for shielding and fixing from outside by supporting electromagnets and springs, Support shaft combined with support shaft and arc-shaped outer side, Cleaner support and cleaner support bent at both ends to allow attachment and detachment In the head cleaner of the video tape recorder composed of the cleaner fixed by.

Hereinafter, the present invention will be described in detail by the accompanying drawings.

2 is a block diagram of an automatic video head cleaning apparatus according to the present invention, in which a microcomputer is built in which a user's key pressure is applied to send an instruction signal to a relevant part or a signal is received from a peripheral part. The control unit 11 and the servo unit 12 for controlling the drum motor at a constant speed and a constant phase according to the signal of the system control unit 11 and the servo unit 12 are controlled by the servo unit 12 to rotate at a constant speed and a constant phase. A head drum 13, a preamplifier 14 for reading and preamplifying the video signal recorded on the magnetic tape, and an image signal processor for receiving the amplified signal from the preamplifier 14 and processing the received video signal into a video signal. 15), an automatic cleaning control unit 16 for detecting a signal amplified by the preamplifier 15 and outputting a detection signal to the system control unit 11, and cleaning according to a detection signal input to the system control unit 11. It consists of a head cleaner (18) actuated by the output signal of the drive unit (17) for outputting a drive signal group.

3 is an exemplary circuit diagram of the automatic cleaning control unit 16 of FIG. 2, which includes an integrator 21 for integrating the signal amplified by the preamplifier 14 and a sampling and holder 22 for sampling and holding the integrated signal at a clock cycle. ) And a comparator 23 for sampling and holding signal as one input and comparing the output signal of the integrator 21 to the other input to the system controller 11.

FIG. 4 is a detailed configuration diagram of the head cleaner 18 shown in FIG. 2, wherein the magnetic field is induced by the application of the current from the driving unit 17, and the permanent magnets are opposed to the electromagnet 31. An axis 33 which shields the magnetic field of 32) and is pushed out when the magnetic field is induced in the electromagnet; Spring 34 provided on the outer side of the support shaft 33 and the magnetic field of the electromagnet 31 to close the permanent magnet 32 to the electromagnet 31 side, and supports the electromagnet 31 and the spring 34 On the cleaner support 38 having a cap 36 attached to the fixed blade 35 that can be fixed from the outside, and the support shaft 33 and the both ends are bent to be detachable by providing grooves at both ends. It consists of the cleaner 39 fixed by this.

The operation of the present invention will be described as follows.

The signal reproduced by the head drum 13 of FIG. 2 is amplified by the preamplifier 14 and converted into an image signal by the signal processing unit 15 in a normal signal processing manner.

In addition, the signal amplified by the preamplifier 14 is applied to the automatic cleaning control unit 16.

In the automatic cleaning control unit 16, the amplified signal of the preamplifier 14 is integrated in the integrator 21 shown in FIG. 3, sampled and held at a clock cycle, and sent to one terminal of the comparator 23. The output signal is sent to the other terminal of the comparator 23 so that it is compared in the comparator 23 and the output compared is input to the system control unit 11 of FIG.

Accordingly, when the head control unit 18 needs to be operated, the system control unit 11 sends a signal to the driving unit 17 so that the head cleaner 18 is driven.

In this case, the head cleaner 18 spaced apart from the head drum 13 as shown in FIG. 5 is in close contact with the head drum 13 as shown in FIG. 5 and performs a cleaning operation.

In more detail with reference to FIG. 4, first, electric current flows through the electromagnet 31 by the driving unit 17 to induce a magnetic field in the electromagnet 31 to push the permanent magnet 32, and the permanent magnet 32. This back surface support 37, the cleaner support 38 and the cleaner 39 are pushed simultaneously, the cleaner 39 is in close contact with the head drum 13 as shown in Fig. 5 (b), the spring 34 is compressed Will be.

At the same time, since the system control unit 11 sends a signal to the servo unit 12 to drive the drum motor to rotate the head drum, the video head is cleaned by the cleaner in close contact with the head drum.

When the video head cleaning is finished according to the signal of the automatic cleaning controller, the head cleaner 18 moves toward the electromagnet 31 by the restoring force of the spring 34 to return to the state as shown in FIG.

By doing so, a series of cleaning operations of the head cleaner 18 is completed.

As described above, according to the present invention, the user does not need to clean the video head from time to time, and the head cleaner adheres to the head by magnetic repulsion, so that the possibility of breakage or wear rate of the head is significantly lower than that of the conventional mechanical method. have.

In addition, it is easy to install and does not require a separate installation space, and the head cleaning operation is automatically completed, there is a very convenient advantage.

Claims (4)

A system controller 11 for receiving the key input and controlling the entire system, a servo unit 12 for outputting a motor drive signal in accordance with a signal from the system controller, and a constant speed and a phase in accordance with the motor drive signal of the servo unit A rotating head drum 13, a preamplifier 14 for reading and preamplifying a signal recorded on a tape, a video signal processor 15 for processing a signal amplified by the preamplifier as a video signal, and the preamplifier The automatic cleaning control unit 16 detects an amplified signal and outputs a detection signal, a driving unit 17 which outputs a driving signal by judging a detection signal of the automatic cleaning control unit by a system control unit, and a driving signal of the driving unit. Automatic cleaning device for a video head of a video tape recorder, which consists of a head cleaner (18) operated accordingly. The apparatus of claim 1, wherein the automatic cleaning control unit comprises an integrator 21 for integrating the signal amplified by the preamplifier, a sampling and holder 22 for sampling and holding the integrated signal at a clock cycle, and And a comparator (23) for comparing an output signal and an output signal of the integrator. The electromagnet 31 in which the magnetic field is induced by the application of electric current, the permanent magnet opposing the electromagnet is embedded so that the electromagnet is pushed out when the magnetic field is induced, and the permanent magnet is brought into close contact with the electromagnet side. And a cap (36) provided with a spring (34) provided on an outer side of the support shaft, and a fixed blade (35) for shielding the magnetic field of the electromagnet and supporting the electromagnet and the spring and fixed from the outside. A video tape recorder comprising: a support (37) fixed to the shaft and moving together with the support shaft, a cleaner support (38) bent at both ends to be detachable from the support, and a cleaner fixed to the support by the cleaner support; Head cleaner. 4. The head cleaner of claim 3, wherein grooves are formed at both ends of the cleaner support so that both ends of the support are fitted into the grooves to be coupled.