JPH0430659Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a rotary head assembly applied to a digital audio tape recorder (DAT) and the like.

(Prior art and its problems) Like video tape recorders, digital audio tape recorders record a wide band of signals, so the magnetic head is rotated to increase the relative speed with the magnetic tape. .

A device equipped with such a rotating magnetic head is called a rotating head assembly, and there are two types: the helical scan method conventionally used in video tape recorders, and the fixed drum method developed by the applicant. .

By the way, in order to spread the use of digital audio tape recorders, etc., the biggest challenge is to reduce the cost of the above-mentioned rotary head assembly, and one solution is to use plastic (resin) for the tape winding drum.
is seen as promising.

However, since the magnetic tape running on the tape winding drum of the rotary head assembly is also made of plastic, the friction between the two generates static electricity, which has a disadvantage in that recorded signals are adversely affected.

(Means for Solving the Problems) The present invention was proposed in view of the above points, and its purpose is to provide a simple structure that can prevent static electricity from forming on the plastic tape winding drum. The object of the present invention is to provide a rotary head assembly that enables

In order to achieve the above object, the present invention provides a rotary head assembly equipped with a plastic tape winding drum, in which a ground portion made of a conductive member is provided near the inlet and/or outlet of the tape running section of the tape winding drum. The gist of the invention is a rotary head assembly characterized in that it is provided with a rotary head assembly.

(Function) In the rotary head assembly of the present invention, a grounding section made of a conductive material is provided near the entrance and/or exit of the tape running section of the plastic tape winding drum, so that the magnetic tape is not electrically charged. Static electricity is removed by the ground portion, preventing the magnetic tape from coming into close contact with the tape winding drum during tape running, and preventing any adverse effects on recorded signals.

(Embodiments) Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the rotary head assembly of the present invention, in which (a) is a plan view with a magnetic tape wound around it, and (b) is a front view with no magnetic tape.

In FIG. 1, reference numeral 1 denotes a rotary head assembly of a fixed drum type that enables the magnetic tape to run in parallel.The tape winding of the rotary head assembly 1 is carried out by an inlet tape guide roller 11 and an outlet tape guide roller 12 provided on both sides. attached drum 2
magnetic tape 13 over a predetermined angle (approximately 90° for digital audio tape recorders).
can be wrapped around it. Also, the tape running portion of the tape winding drum 2 (magnetic tape 13
Ground portions 5A and 5B made of a conductive member are provided near the entrance and exit of the winding portion) and are connected to the chassis or the like via lead wires or the like. In addition, if the generation of static electricity is relatively small, the grounding parts 5A and 5B
Only one of them may be used. In addition, the ground portion 5A,
5B is provided near the entrance and exit of the tape running section, because if it is installed in the tape running section, the tape running surface will not be flat, and the magnetic tape 1
This is because it distorts the signal and has an adverse effect on signal recording.

FIG. 2 shows the structure of the rotary head assembly 1 in more detail, with A being a perspective view and B being an exploded perspective view. The present invention is applicable not only to the fixed drum type rotary head assembly shown in the drawings but also to conventional helical scan type rotary head assemblies.

In FIG. 2, 2 is a tape winding drum on which the magnetic tape runs, and this tape winding drum 2 is composed of an upper drum 2A and a lower drum 2B. Head passage holes 3 are formed in the curved surface on which the magnetic tape runs in the assembled state. In addition, when the tracking recorded on the magnetic tape is a straight line, the correction curve formed on the flange portion 4 becomes a waveform (waveform).
Since adhesion deteriorates in the valleys, one or more tape pushers 6 are provided at the upper end of the upper drum 2A to face the valleys of the curve in order to force the magnetic tape to follow the curve. On the other hand, inside the tape winding drum 2, a head rotating plate 7 having a magnetic head 8 arranged on its circumference is disposed diagonally, so that the magnetic head 8 is exposed through the head passage hole 3 of the tape winding drum 2. ing. Note that the curved surface of the tape winding drum 2 on which the magnetic tape runs has a planar shape of approximately an ellipse because the head rotary plate 7 rotates in an inclined state. On the other hand, 9 is a motor shaft, and 10 is a motor section (motor or pulley), which constitute the rotating head assembly 1.

FIG. 3 shows an example of a specific configuration of the grounding parts 5A and 5B in FIGS. 1 and 2, and FIG. 3 shows an example in which small pieces 5a made of conductive plastic are inserted from above and below the tape winding drum 2. , B is an example in which the metal rod 5b is inserted from the top and bottom of the tape winding drum 2, C is an example in which a metal press 5c is press-fitted into the tape winding drum 2, and D is an example in which conductive paint 5d is applied to the tape winding drum 2. This is an example. Note that the connection with the lead wires is made by soldering, conductive adhesive, conductive paint, or the like.

1 to 3, when the magnetic tape 13 is wound around the tape winding drum 2 of the rotary head assembly 1 and runs, the magnetic tape 13 comes into contact with the ground portions 5A and 5B, and the tape Static electricity generated by friction with the winding drum 2 disappears immediately, preventing the magnetic tape 13 from coming into close contact with the tape winding drum 2 during tape running, and preventing any adverse effects on recorded signals. It is something.

(Effects of the invention) As described above, in the present invention, in a rotary head assembly equipped with a plastic tape winding drum, a conductive part is provided near the inlet and/or outlet of the tape running section of the tape winding drum. Since we have provided a grounding section made of parts,
Even if static electricity is generated due to friction between the tape winding drum and the magnetic tape, the grounding part removes the static electricity charged on the magnetic tape, prevents the magnetic tape from coming into close contact with the tape winding drum during tape running, and prevents recording. This has the effect that there is no adverse effect on the signal being received.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the rotary head assembly of the present invention, FIG. 2 is a detailed diagram of the rotary head assembly, and FIG. 3 is a specific block diagram of the ground section. DESCRIPTION OF SYMBOLS 1... Rotating head assembly, 2... Tape winding drum, 2A... Upper drum, 2B... Lower drum, 3... Head passage hole, 4... Flange portion, 5
A, 5B...Earth part, 5a...Small piece, 5b...
Metal rod, 5c...metal press product, 5d...conductive paint, 6...tape press, 7...head rotating plate,
8...Magnetic head, 9...Motor shaft, 10...Motor section, 11...Entrance tape guide roller, 12
...Exit tape guide roller, 13...Magnetic tape.

Claims (1)

[Scope of utility model registration request] A rotary head assembly equipped with a plastic tape winding drum, characterized in that a grounding section made of a conductive member is provided near an inlet and/or an outlet of a tape running section of the tape winding drum. .