JPH0525041Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

This invention relates to a channel arrangement of rotary heads mounted on a rotary drum and coupled by a rotary transformer, and more particularly to a channel arrangement of a rotary transformer with respect to a rotary erase head.

[Conventional technology]

In magnetic recording and reproducing devices using a rotating head mechanism, such as VTRs and digital audio tapes, a rotating transformer is generally used to electrically connect the rotating head to a stationary electronic circuit. This rotating transformer has coil winding grooves cut into a flat (or coaxial) magnetic core so that the stator side (fixed side) and rotating side coils face each other, and the coils are installed. It is designed to transmit signals without contact. The number of rotary transformers is equal to the number of rotary heads. On the other hand, the rotary head disposed on the rotary drum may be equipped not only with a head for recording and reproducing video signals, but also with a rotary head for erasing video signals.
The FE head (hereinafter referred to as FE head) has high utility value by improving the quality of the connecting part during recording.
It can also be effectively used when erasing only a portion of a track that is recorded diagonally on a tape with a rotating head (immediately after that is recorded with a video head), such as the PCM recording area in . Conventionally, since such FE heads were coupled to respective rotary transformers, it was necessary to prepare a rotary transformer channel for each FE head and rotary head for recording and reproduction. And F.E.
The channel arrangement of the rotary transformer for the rotary head including the head is such that the rotary transformer for the FE head is arranged adjacent to the rotary transformer so that the erase current of the FE head does not affect the transmission path of the rotary head that performs recording and playback. It was common. Further, the transmission line of the rotary head, which was not used at that time, was connected to an appropriate load on the stator side (fixed side) of the rotary transformer.

[Problem that the invention attempts to solve]

A conventional magnetic recording/reproducing device equipped with an FE head is configured as described above, so that when an erase current is supplied to one side of the FE head via a rotary transformer, an erase current is supplied to the other side of the FE head. However, due to current crosstalk between the channels of the rotating transformer, the FE head, which originally does not supply erase current, and other recording (playback)
This has the disadvantage that an erase current flows into the head and the read head, causing inconvenience. This invention was made in order to eliminate the above-mentioned drawbacks, and aims to provide a magnetic recording and reproducing device that can sufficiently reduce current crosstalk between channels of a rotating transformer provided in a rotating drum. It is something.

[Means to solve the problem]

In order to achieve the above object, this invention provides a magnetic recording and reproducing apparatus in which a rotating drum includes a pair of rotating heads including a pair of rotating erasing heads, and each of the rotating heads is coupled to a rotating transformer. The coils of the rotary transformers coupled to the rotary heads other than the pair of rotary erase heads are disposed between the respective coils of the rotary transformers coupled to the erase heads, and when the rotary erase heads are operated, the pair of rotary erase heads The invention is characterized in that the stator side coils of the rotary transformers connected to the rotary heads, except for the rotary erase head, are short-circuited.

【Example】

An embodiment of this invention will be described below with reference to the drawings. FIG. 1 is a half-sectional view showing the channel position configuration of a rotary transformer according to this invention. In the figure, reference numeral 1 is a stator of the rotary transformer, and this stator 1 includes one coil 2a of each channel.
~2e are arranged. Here, coils 2a, 2
c are the channels of the first and second FE heads, coil 2b is the channel of the rotary head for reproduction, and coils 2d and 2e are the rotary transformer elements on the stator 1 side corresponding to the channels of the rotary head for recording (reproduction), respectively. It consists of The coil 2b is always short-circuited when the FE head is operated. FIG. 2 is a plan view showing the arrangement of the rotary heads including the FE head provided on the rotary drum, where 3 is the first FE head, 4 is the reproduction rotary head,
5 is a second FE head provided 180 degrees opposite to the first FE head 3; 6 is a recording rotary head; 7 is provided 180 degrees opposite to the first recording rotary head 6. This is a second rotary recording head. The operation of the magnetic recording and reproducing apparatus configured in this way will be explained with reference to FIGS. 3 and 4. First,
When the first FE head 3 is used, the erase current circuit 8 is connected to the stator side coil 2a of the rotary transformer T.
is connected, and an erase current is supplied to the first FE head 3 via the rotary transformer T of this channel. Similarly, when the second FE head 5 is used, the erase current is supplied to the second FE head 5 from the erase current circuit 8 via the rotary transformer T of the channel. In this case, the first and second FE
When the heads 3 and 5 are in operation, the channel of the rotary transformer T corresponding to the reproducing rotary head 4 disposed between them is always short-circuited on the stator side. Note that in FIGS. 3 and 4, reference numeral 9 indicates the load on the stator side coil of the rotary transformer T in each channel. Figures 5 and 6 show the crosstalk between the channels of the reproducing rotary head 4 when the first FE head 3 and the second FE head 5 are in operation, with a load and when the channels are short-circuited. This shows that when the stator side of the rotary transformer T in the channel of the reproducing rotary head 4 is short-circuited, channel crosstalk is reduced (the amount of crosstalk from 15 to 20 dB is improved to 40 dB). . Here, the horizontal axes 1 to 5 (ch) in the figure represent the first FE head 3, the reproducing rotary head 4, and the second
Channels corresponding to the FE head 5 and recording rotary heads 6 and 7 are shown. In addition, in the above-mentioned embodiment, crosstalk can be further improved by inserting and arranging a short ring between each channel of the rotary transformer T.

[Effect of the idea]

As described above, according to this invention, the current flowing to the activated FE head does not flow to the inactive FE head, other recording (playback) heads, or playback heads, and there is no current crosstalk between channels. Talk can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the channel configuration of the rotary transformer according to this invention, Fig. 2 is a diagram showing the arrangement of the rotary head provided on the rotary drum, and Figs. circuit diagram,
FIGS. 5 and 6 are diagrams showing actual measured values according to this invention to explain channel crosstalk. 1...Stator, 2a-2e...Coil, 3...
...first FE head, 4... rotary head for reproduction,
5... Second FE head, 6, 7... Recording rotary head, 8... Erase current circuit, 9... Load, T...
...Rotating transformer.

Claims (1)

[Claims for Utility Model Registration] In a magnetic recording and reproducing device, a rotating drum includes a pair of rotating erasing heads, each of which is coupled to a rotating transformer. The coils of the rotary transformer coupled to the rotary heads other than the pair of rotary erase heads are disposed between the respective coils of the rotary transformer, and when the rotary erase heads are activated, the coils of the rotary transformer are A magnetic recording/reproducing device characterized in that a stator side coil of a rotary transformer connected to a rotary head other than the rotary head is short-circuited.