JPH06103729A - Magnetic tape cleaning mechanism for recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent a whole width erasing head from clogging, etc., by disposing a member for preventing a backflow of dust at the time of rewinding a tape in contact with the tape on the upstream side of a blade in a tape traveling system. CONSTITUTION:The magnetic tape cleaning mechanism is composed of the blade 22 and the backflow preventing member 23 disposed between the blade 22 and the whole width erasing head 13. At the time of recording and reproducing, dust stuck to a recording surface of the tape 6 is removed by the magnetic blade 22, and at the time of rewinding the magnetic tape, dust to be stuck again to the magnetic tape 6 is removed by the backflow preventing member 23 with such an arrangement that dust is fed out from an edge part 24 of the blade. By this method, dust in the backflow is prevented from sticking to the tape to be wound up around a supply reel as it is, and hence a drop-out and clogging of the whole width erasing head can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a cassette type recording / reproducing apparatus such as a VTR for removing dust and the like adhering to the recording surface of a magnetic tape, and removing the dust and the like when rewinding the magnetic tape. The present invention relates to a magnetic tape cleaning mechanism which has a simple structure and can reliably prevent backflow to the full-width erasing head side to cause so-called head clogs and the like.

[0002]

2. Description of the Related Art As a magnetic tape cleaning mechanism of a recording / reproducing apparatus, as shown in FIG. 4, a blade 101 composed of an abrasion resistant member is brought into contact with a recording surface of a magnetic tape 102 and is attached to the recording surface. After removing the magnetic powder (attached after dropping from the magnetic tape 102) and dust by scraping it off, the magnetic tape 102 is removed.
Is known to prevent the dropout and the deterioration of the error rate by sending it to the rotary head drum 103 as a recording / reproducing unit (for example, Japanese Laid-Open Patent Publication No. HEI 3-
203079).

[0003]

By the way, the conventional magnetic tape cleaning mechanism described above is used for a while, as shown in FIG.
The magnetic powder, dust 105, etc., removed from the magnetic tape 102 start to accumulate, and when these dust 105 etc. remain for a certain amount or more, they adhere to the magnetic tape 102 and flow backward when rewinding, which causes the following problems. was there.

(1) Magnetic powder, dust, and the like that flow backward during rewinding adhere to the head gap of the full-width erasing head 106,
Causes head clogs.

(2) Magnetic powder, dust, and the like that flow backward during rewinding are wound on the supply reel 107 and are pressed and solidified by the winding tension, which causes dropout.

The present invention solves the above-mentioned conventional problems and prevents backflow of magnetic powder, dust and the like remaining on the edge portion of the blade during rewinding, and causes backflow of magnetic powder and dust. It is possible to reliably prevent magnetic powder, dust, and the like from being caught in the clog of the full-width erasing head and the supply reel, which is caused by the simple structure.

[0007]

In order to solve the above problems, in the invention of claim 1, the magnetic tape cleaning mechanism contacts the recording surface of the magnetic tape to remove dust and the like adhering to the recording surface. A blade that sends the magnetic tape to the recording / playback unit side after removal, and contacts the recording surface of the magnetic tape on the upstream side of the tape running system of the blade, and rewinds the magnetic tape from the blade when rewinding the magnetic tape. It is composed of a backflow prevention member that removes dust and the like that have adhered.

According to a second aspect of the present invention, in the magnetic tape cleaning mechanism according to the first aspect, the backflow preventing member is arranged between the blade and the full width erasing head.

According to a third aspect of the present invention, in the magnetic tape cleaning mechanism according to the second aspect, the backflow preventing member and the blade are integrally formed.

[0010]

According to the invention of claim 1, at the time of recording / reproducing, dust or the like adhering to the recording surface of the magnetic tape is removed by the blade and the magnetic tape is sent to the rotary head drum to cause dropout or error rate. Prevent the deterioration of. Further, when rewinding the magnetic tape, dust or the like attached to the magnetic tape again as it is fed from the edge portion of the blade is removed from the magnetic tape by the backflow prevention member and wound on the supply reel. Is prevented.

Further, according to the second aspect of the invention, since the backflow preventing member is arranged between the blade and the full width erasing head, the dust and the like flowing back from the blade at the time of rewinding is immediately removed by the backflow preventing member. , Is prevented from adhering to the full width erase head.

Further, according to the third aspect of the present invention, since the blade and the backflow prevention member are integrally formed, if the blade is attached to the recording / reproducing apparatus, the backflow prevention member can be attached to the recording / reproducing apparatus at the same time. As a result, the workability of assembling can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic tape cleaning mechanism of the present invention will be described below as an example when it is incorporated in a cassette type VTR as a recording / reproducing apparatus.

FIG. 1 is a plan view showing the outline of a tape traveling system of a cassette type VTR.

When the tape cassette 1 is mounted in the cassette mounting position of the VTR, the supply reel 4 and the winding reel 3 of the tape cassette 1 are mounted on the supply reel base 2 and the take-up reel base 3 arranged in the cassette mount position. The reel 5 is mounted and the first tape is placed inside the magnetic tape (metal tape) 6 wound around the supply reel 4 and the take-up reel 5.
~ The fourth loading guides 7 to 10 and the pinch roller 11 are inserted (see the chain double-dashed line in Fig. 1).

When a sensor (not shown) detects that the tape cassette 1 has been mounted at the cassette mounting position, the first to fourth loading guides 7 are provided.
-10 and the pinch roller 11 move to the position shown by the solid line in FIG.
Is wound around the rotary head drum as the recording / reproducing unit 12 at a predetermined winding angle, the upstream side of the magnetic tape 6 with respect to the rotary head drum is brought into contact with the full-width erasing head 13, and the downstream side is connected to the audio erasing head 14. And audio
The CTL head 15 and the simultaneous recording / playback confirmation reproducing head 16 are brought into contact with each other.

When the recording / reproducing mode is set after the loading, the pinch roller 11 presses the magnetic tape 6 onto the capstan 17 and the take-up reel 5 rotates in the take-up direction to run the magnetic tape 6 at a low speed. Then, recording / playback is performed by the rotary head drum.

When rewinding, the pinch roller 11 separates from the capstan 17 and the supply reel 4 rotates to rewind the magnetic tape 6 to the supply reel 4 side.

In FIG. 1, reference numeral 21 is a magnetic tape cleaning mechanism of the present invention. The cleaning mechanism 21 is in contact with the recording surface of the magnetic tape 6 and magnetic powder, dust or the like attached to the recording surface. Of the magnetic tape 6 on the upstream side of the tape running system of the blade 22 and the recording surface of the magnetic tape 6 at the upstream side of the tape traveling system of the blade 22 after the removal.
Backflow prevention member 2 for removing dust and the like reattached to the recording surface of
It consists of 3.

The blade 22 is made of ruby, sapphire,
It is formed in a rectangular parallelepiped shape by a non-magnetic wear-resistant member such as ceramics, and a pair of left and right edge portions 24, 24 are provided on both side portions on the front side.

Then, the tip end of the one edge portion 24 is inclined at a desired inclination angle θ (5 °) with respect to the magnetic tape 6.
It is arranged on the upstream side of the rotary head drum in a state of being in contact with the recording surface at about 30 °) and scrapes off magnetic powder, dust 25, etc. adhering to the recording surface during recording or reproduction. It is designed to be removed.

The backflow preventing member 23 is made of a non-magnetic metal or ceramic and is formed in a so-called pin shape.

The backflow preventing member 23 is disposed between the blade 22 and the full-width erasing head 13 substantially in parallel with the magnetic tape 6, and its peripheral surface comes into contact with the recording surface of the magnetic tape 6. At the time of rewinding, the dust 25 or the like reattached to the magnetic tape 6 from the blade 22 is removed to prevent the dust or the like from flowing back to the full width erasing head 13 side.

The blade 22 and the backflow prevention member 23 are integrated by being attached to a holder 26. By fixing the holder 26 to a support plate 28 with a screw 27, the blade 22 and the backflow prevention member 23 are joined together. At the same time, it can be mounted on the support plate 28.

Magnetic tape cleaning mechanism 21 of the embodiment
Since it has the above configuration, during recording or playback,
The dust or the like adhering to the recording surface of the magnetic tape 6 is removed by the blade 22, and the magnetic tape 6 is sent to the rotary head drum for recording or reproduction.

When recording or reproducing is performed for a long time, dust or the like remains on the edge portion 24 of the blade 22, and the dust or the like reattaches to the magnetic tape 6 during rewinding, and together with the magnetic tape 6, the full-width erasing head. There is a risk that it will be returned to the 14 side.

At this time, the backflow preventing member 23 in contact with the recording surface of the magnetic tape 6 acts between the blade 22 and the full-width erasing head 14 to remove dust and the like from the recording surface to remove the dust and the like. Is sent to the full-width erasing head 14 side.

In the embodiment shown in the drawings, the blade 22
Although the case where the backflow prevention member 23 and the backflow prevention member 23 are integrated is shown, each of them may be independent.

The mounting positions of the blade 22 and the backflow preventing member 23 are not limited to between the rotary head drum and the full width erasing head 14.

[0030]

The magnetic tape cleaning mechanism of the present invention has the following effects.

(1) A backflow preventing member prevents a backflow of dust or the like from the blade at the time of rewinding, and the dust or the like that has backflowed is wound around the supply reel and is compacted as in the conventional case. And the like can be reliably prevented.

(2) By providing the backflow preventing member between the blade and the full width erasing head, it is possible to prevent the clog of the full width erasing head caused by the backflow of dust or the like at the time of rewinding.

(3) Since the backflow preventing member may be provided outside the blade, the structure is simple. In particular, by integrating the blade and the backflow prevention member, it is possible to reduce the number of parts and improve the workability of assembly.

[Brief description of drawings]

FIG. 1 is a plan view of a tape running system.

FIG. 2 is a perspective view of a main part.

FIG. 3 is a schematic plan view of a main part.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a plan view showing a problem of the conventional example.

[Explanation of symbols]

 6 ... Magnetic tape 12 ... Recording / reproducing part (rotating head drum) 13 ... Full width erasing head 21 ... Magnetic tape cleaning mechanism 22 ... Blade 23 ... Backflow prevention member

Claims (3)

[Claims] 1. A blade that contacts a recording surface of a magnetic tape and removes dust and the like adhering to the recording surface before sending the magnetic tape to a recording / reproducing section side; and a blade running upstream of the tape running system. A magnetic field of a recording / reproducing apparatus, which is constituted by a backflow preventing member that comes into contact with the recording surface of the magnetic tape and removes dust and the like reattached to the magnetic tape from the blade when the magnetic tape is rewound. Tape cleaning mechanism. 2. A magnetic tape cleaning mechanism for a recording / reproducing apparatus according to claim 1, wherein a backflow preventing member is arranged between the blade and the full width erasing head. 3. A magnetic tape cleaning mechanism for a recording / reproducing apparatus according to claim 2, wherein the backflow preventing member and the blade are integrally formed.