JPH03286403A - Rotary head type recording/reproducing device - Google Patents

Abstract

PURPOSE:To reduce the crosstalk of a recording signal to a regenerative signal at the time of simultaneous reproducing, and to improve the quality of a picture by supplying the recording signal to a recording head through the rotary head of one side, and taking out the reproducing signal from a reproducing head to the outside of a rotary head drum through the rotary transformer on the other side. CONSTITUTION:Two sets of the rotary transformers 18, 19 are arranged in the rotary head drum 10 so as to be positioned at the upper and the lower parts of the plane of rotation of the heads 16, 17. The lower side rotary transformer 18 is used for transmitting the recording signal, and the upper side rotary transformer 19 is used for transmitting the reproducing signal. When one side 18 of two sets of the rotary transformers 18, 19 is used for the transmission of the recording signal, and the other side 19 is used for the transmission of the reproducing signal in this way, a recording signal transmission route and a reproducing signal transmission route are separated at the boundary of the plane of rotation of the heads 16, 17. Thus, the crosstalk of the recording signal to the regenerative signal is lessened.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to a rotary head type recording and reproducing device such as a helical scan VTR, and particularly to a simultaneous recording and reproducing device that can immediately reproduce and check recorded contents during recording. The present invention relates to a recording/playback device with a playback function.

(Prior art) A magnetic head is mounted on the outer circumferential surface of a rotating drum, and a video signal is recorded while the magnetic tape is wound over a certain angle range on the outer circumferential surface of the rotary head drum, which is made up of a rotating drum and a fixed drum. Helical scan VTRs for playback are widely used for both consumer and business use.

Compared to consumer (home) VTRs, professional VTRs are generally more expensive to record programs, and it is often difficult to reshoot them, so the purpose of recording failures is to Therefore, it is required to have a so-called simultaneous playback function that allows the user to immediately check the recorded content by playing it back while it is being recorded.

The rotating head drum of a VTR with this simultaneous playback function is
It is constructed as schematically shown in FIGS. 5 and 6.

In FIG. 5, a rotary head drum 50 is a rotary drum 5.
The rotating drum 51 is directly connected to a drum motor 55 via a rotating shaft 54 supported by a bearing 53. A plurality of recording heads 56 and a plurality of reproducing heads 57 are attached to the rotating drum 51, and simultaneous reproduction can be performed by scanning the track immediately after a signal is recorded by the recording head 56 with the RAD 57 for reproduction.

A recording signal is transmitted from the outside into the rotary head drum 50 by a rotary transformer 58, and is supplied to the recording head 56 via a signal line 60 shown in FIG. 6 on a printed circuit board 59. As a result, a recording current flows through the recording head 56, and recording is performed on the tape. On the other hand, during simultaneous reproduction, the signal recorded on the tape is reproduced by the reproduction head 55, and the obtained signal is amplified by the reproduction amplifier IC 61 shown in FIG. 6 mounted on the printed circuit board 59, and then 58 to the outside.

In a VTR having such a simultaneous playback function, it is difficult to improve the playback image quality in the simultaneous playback mode. The reproducing current induced from the tape to the reproducing head 57 is a minute current, several hundred times smaller than the recording current. Therefore, if part of the recording current leaks into the reproducing current in the simultaneous reproduction mode, the images of the simultaneous reproduction will be distorted. It will disturb it. This makes it difficult to correctly monitor the recording state through simultaneous playback.

This problem increases as rotating head drums become smaller.

Furthermore, when a magnetic recording medium with strong coercive force such as a metal tape is used to achieve high density, a large recording current is required, which further increases the crosstalk between the recording current and the reproduction current during simultaneous reproduction. , it has become a serious problem.

(Problems to be Solved by the Invention) As described above, in the conventional technology, there is a problem in that during simultaneous reproduction, tally talk of the recording current to the reproduction current occurs, impairing the reproduced image quality.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary head type recording and reproducing apparatus that can reduce cross-over of recorded signals to reproduced signals during simultaneous reproduction and improve reproduced image quality.

[Structure of the Invention] (Means for Solving the Problems) The first feature of the present invention is that rotary transformers are provided above and below the rotating surfaces of the recording head and the reproducing head in the rotary head drum, and the recording on the recording head is The structure is such that a signal is supplied to the recording head through one rotary head, and a reproduced signal from the reproducing head is taken out to the outside of the rotary head drum through the other rotary transformer.

The second feature of the present invention is that the rotary head drum has a ground conductor layer on both sides almost fully opened, and the printed circuit board has a signal line in the inner layer for transmitting a recording signal to the recording head or a reproduction signal from the reproduction head. This is because we have established

A third feature of the present invention is that the rotary head drum has a ground conductor layer on almost the entire surface of one surface, and the recording head and the reproducing head are provided on the surface opposite to the ground conductor layer from the recording head and the reproducing head. A printed circuit board having a signal line for transmitting a recording signal to the recording head or a reproduction signal from the reproduction head is provided.

(Function) When one of the two sets of rotary transformers is used to transmit recording signals and the other is used to transmit reproduction signals, the recording signal transmission path and the reproduction signal transmission path are separated with the rotating surface of the head as a boundary. Therefore, crosstalk between the recorded signal and the reproduced signal is reduced.

In addition, if the printed circuit board has a three-layer structure with ground conductor layers on both sides and signal lines on the inner layer, and the signal line on the inner layer is used to transmit recording signals or playback signals, the signal line will be electrostatically prevented by the ground conductor layers on both sides. or magnetically shielded,
Crosstalk of the recorded signal to the reproduced signal is reduced.

Furthermore, if a ground conductor layer is formed on one surface of the printed circuit board, and a signal line for transmitting the recording signal or reproduction signal is formed on the surface opposite to the ground conductor layer from the recording head and the reproduction head, the signal line is formed. Since the head is electrostatically or magnetically shielded by the ground conductor layer, crosstalk between the recorded signal and the reproduced signal due to electromagnetic waves leaking from the head to the outside is reduced.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view showing the configuration of a rotary head drum section in a rotary head type recording/reproducing apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view showing the arrangement of the head.

In FIG. 1, a rotary head drum 10 is a rotary drum 1.
The rotating drum 11 is directly connected to a drum motor 15 via a rotating shaft 14 supported by a bearing 13. As shown in FIG. 2, a plurality of recording heads 16 and a plurality of reproducing heads 17 (two in the example shown) are respectively attached to the rotating drum 11 at positions shifted by 45 degrees from each other. In the simultaneous playback mode, simultaneous playback is performed by scanning the track immediately after a signal is recorded by the recording head 16 with the playback head 17.

Inside the rotary head drum 10, two sets of rotary transformers 1, 8, and 19 are arranged above and below the rotating surface of the head 16, 17, respectively. The lower rotary transformer 18 is used for transmitting recording signals, and the upper rotary transformer 19 is used for transmitting reproduction signals. The rotating element of the lower rotary transformer 18 is connected to the rotating shaft 14, and the stationary element is connected to the fixed drum 1.
2 are fixed respectively. The rotating side element of one upper rotary transformer is fixed to the rotating shaft 14, and the stationary side element is fixed to the coupling drum 20, respectively. The connecting drum 20 is arranged so as to surround the outside of the rotary head drum 10, and supports the fixed side of the rotary transformer 19 on its upper wall by screws or other means (not shown), and the lower end side is connected to the fixed drum 12.
It is fitted onto the outer periphery of and fixed by screws or other means (not shown).

Furthermore, two printed circuit boards 21 and 22 are provided within the rotary head drum 10. First printed circuit board 2
1 is fixed on the rotating element of the lower rotary transformer 18, and the second printed circuit board 22 is placed at a predetermined distance above the printed circuit board 21 with a spacer 23 in between. FIGS. 3 and 4 are cross-sectional views showing detailed structures of the first and second printed circuit boards 21 and 22, respectively.

As shown in FIG. 3, the first printed circuit board 21 has a three-layer conductor structure having ground conductor layers 31 and 32 on almost the entire surface of both sides and a signal line 33 in the inner layer.
Interlayer insulating layers 34 and 35 are provided between the layers 31 and 32 and the signal line 33. The ground conductor layers 31, 32 are electrically connected to the ground potential point of the recording/reproducing device.

A connection terminal 36 formed by etching the ground conductor layer 31 is provided on the surface on which the ground conductor layer 31 is provided, and this connection terminal 36 receives a signal via a connecting conductor 37 that penetrates the interlayer insulating layer 34. It is connected to one end of the line 33 on the inner peripheral side of the drum.

On the other hand, on the surface where the ground conductor layer 32 is provided, connection terminals 3 are formed by etching the ground conductor layer 32.
8 is provided, and this connecting terminal 38 is connected to one end on the outer peripheral side of the signal line 33 via a connecting conductor 39 penetrating the interlayer insulating layer 35. The connecting terminal 36 is connected to the rotating element of the rotating transformer 18 shown in FIG.
8 is connected to the recording head 16 shown in FIGS. 1 and 2.

Note that in this printed circuit board 21, the interlayer insulating layer 34
．． One of the substrates 35 may be an insulating substrate, and each layer may be formed on both sides of the substrate, or a structure may be employed in which two printed circuit boards are pasted together, with the interlayer insulating layers 34 and 35 serving as insulating substrates.

As shown in FIG. 4, the second printed circuit board 22 has a ground conductor layer 42 on almost the entire lower surface of the insulating substrate 41, and the recording head 16 and a signal line 43 on the surface opposite to the reproducing head 17. A connection terminal 44 formed by etching the ground conductor layer 42 is provided on the surface on which the ground conductor layer 42 is provided. It is connected to one end of the line 43 on the outer peripheral side of the drum.

On the other hand, the signal line 43 is divided in the middle, and a regenerative amplifier IC 46 is mounted at the divided part.

Although the IC 46 is mounted using a blip-chip method using face-down bonding in the figure, wire bonding or other methods may be used. One end of the signal line 43 on the inner peripheral side of the drum is a connecting terminal 47, and this connecting terminal 47 is connected to the rotating element of the rotating transformer 19 shown in FIG. Further, the connection terminal 44 is connected to the reproducing head 17 shown in FIGS. 1 and 2.

Next, the operation of the apparatus of this embodiment will be explained.

During simultaneous playback, a recording signal, for example a video signal, is transmitted from the outside to the inside of the rotary head drum 0 by a lower rotary transformer 18, and is further recorded from the rotary transformer 18 via a signal line 33 in the first printed circuit board 21. head 16
supplied to As a result, a recording current corresponding to the video signal flows through the recording head 16, and recording is performed on a tape (not shown) that is wound diagonally around the outer periphery of the rotary head ram 10 and runs in the longitudinal direction.

On the other hand, the signal recorded on the tape in this way is transmitted to the playback head 1.
7, it is immediately regenerated. As a result, the playback head 17
The regenerative current outputted from the is led to the regenerative amplifier IC46 via the signal line 43 on the printed circuit board 22, and the current -
After voltage conversion and amplification, the upper rotating transformer 19
is led to the outside through

In this case, the recording signal and the reproduction signal are transmitted to the end 16.
Since the recording speed passes through the lower and upper rotating transformers 18 and 19, which are provided with the rotating surface of 17 as the boundary, compared to the conventional configuration in which the rotating transformers are placed only on one side, the recording speed during simultaneous playback is Current does not easily leak into the reproduction current.

Shikamo, rotating head drum 10 by rotating transformer 18
The recording signal guided inside is supplied to the recording head 16 through the signal line 33 in the inner layer, which is electrostatically or magnetically shielded from the reproduction side by ground conductor layers 31 and 32 on both sides of the printed circuit board 21. Therefore, crosstalk between the recording current and the reproducing current is further reduced.

Further, the reproduction current from the reproduction head 17 is transmitted to the heads 16, 17 by a ground conductor layer 42 on the printed circuit board 22.
signal line 43 electrostatically or magnetically shielded from
and the rotary transformer] 9 via the reproducing amplifier LC46, crosstalk of the recorded signal to the reproduced signal due to electromagnetic waves leaking to the outside from the recording head 16 is reduced.

Note that the present invention is not limited to the above embodiments,
Various modifications can be made.

For example, in the embodiment, (2) two sets of rotary transformers 18, 19 are provided for transmitting recording signals and reproduction signals, (3) a third rotary transformer having ground conductor layers 31, 32 on both sides and a signal line 33 in the inner layer;
The printed circuit board 21 shown in the figure is used to transmit recording signals, and (1) a fourth circuit board having a ground conductor layer 42 on one surface and a signal line 43 on the surface opposite to the head 16, 17 with respect to the ground conductor layer 42; Although the printed circuit board 22 in the figure is used to transmit the reproduced signal, the crosstalk reduction effect can be obtained even if these three techniques (■■■) are implemented alone or in any two combinations.

Furthermore, the printed circuit board 21 shown in FIG. 3 may be used for transmitting reproduction signals, and the printed circuit board 32 shown in FIG. 4 may be used for transmitting recording signals.

[Effects of the Invention] According to the present invention, crosstalk between a recorded signal and a reproduced signal during simultaneous reproduction can be effectively reduced,
This effect is particularly significant when the rotating head drum is downsized and the packaging density is increased, or when a high coercive force medium such as a metal tape is used.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the configuration of a co-rotating head drum section according to an embodiment of the present invention, FIG. 2 is a plan view showing the arrangement of the head in the same embodiment, and FIG. FIG. 4 is a cross-sectional view showing the structure of the second printed circuit board, FIG. 5 is a cross-sectional view showing the structure of the conventional rotary head drum section, and FIG. It is a perspective view showing the composition of the printed circuit board in the figure. lO... Rotating head drum 11... Rotating drum 1
2... Fixed drum 13... Bearing 14...
Rotating shaft 15...Drum motor 16...
Recording heads 18, 19... Rotating transformers 21, 22... Printed circuit board 33... Signal lines 36, 38... Connection terminal 41... Insulating substrate 43... Signal line 45... Connection Conductor 17...Reproduction head 20...Connection drums 31, 32...Conductor layers 34, 35...Interlayer insulation layers 37, 39...Connection conductor 42...Ground conductor layers 44, 47... ... Connection terminal 46 ... Regenerative amplifier IC Fig. 1 16

Claims (3)

[Claims] (1) In a rotary head type recording and reproducing device that records and reproduces a tape by winding it around a rotary head drum that includes a rotary drum to which at least a recording head and a reproducing head are attached, and running the tape in the longitudinal direction, recording in the rotary head drum. Rotary transformers are provided above and below the rotating surfaces of the head and playback head, and the recording signal to the recording head is supplied to the recording head through one rotary head, and the playback signal from the playback head is supplied through the other rotary transformer. A rotary head type recording/reproducing device characterized by having a configuration in which the rotary head is taken out from the drum. (2) In a rotary head type recording and reproducing device that performs recording and reproducing while winding a tape around a rotary head drum including a rotary drum to which at least a recording head and a reproducing head are attached and running the tape in the longitudinal direction, in the rotary head drum, A rotary head type recording/reproducing device characterized by having a printed circuit board having a ground conductor layer on almost the entire surface of both sides and having a signal line in an inner layer for transmitting a recording signal to a recording head or a reproduction signal from a reproduction head. . (3) In a rotary head type recording and reproducing device that performs recording and reproducing while winding a tape around a rotary head drum including a rotary drum to which at least a recording head and a reproducing head are attached and running the tape in the longitudinal direction, in the rotary head drum, A ground conductor layer is provided on almost the entire surface of one surface, and a signal for transmitting a recording signal to the recording head or a reproduction signal from the reproduction head is provided on the surface opposite to the recording head and the reproducing head with respect to the ground conductor layer. A rotary head type recording/reproducing device characterized by being provided with a printed circuit board having a track.