JPH0728602Y2 - Rotating head assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a rotary head assembly used for recording and reproducing a signal on a magnetic tape in a digital audio tape recorder (DAT) or the like.

(Prior Art) In a digital audio tape recorder or the like, since the band of a signal to be recorded is wide, it is necessary to increase the relative speed between the magnetic tape and the magnetic head. Therefore, a so-called rotary head method for rotating the magnetic head is generally used. Has been adopted as Also, oblique scanning is predominant because of the long scanning line length and other reasons.

FIG. 11 shows a main part of a conventional digital audio tape recorder or the like which adopts a rotary head system, and the rotary head assembly 21 is generally provided to be inclined. Then, the magnetic tape 28 pulled out from the tape cassette 27 is obliquely wound around the drum 22 of the rotary head assembly 21 via the entrance tape guide roller 29 and the entrance tilt guide 30, and the exit tilt guide 31 and the exit tape guide roller 32. Then, it is returned to the inside of the tape cassette 27 via the capstan shaft 33 and the pinch roller 34. In addition, the entrance inclination guide
The outlet inclination guide 31 guides the magnetic tape 28 so that the magnetic tape 28 wound in parallel and housed in the tape cassette 27 is obliquely wound around the drum 22 without slack.

Further, FIG. 12 shows only the rotary head assembly 21, and the drum 22 has an upper drum 22A and a fixed lower drum 22B that rotate at a high speed by receiving power from a motor shaft 25 and a motor unit 26.
And a magnetic head 24 on the circumference of the upper drum 22A.
Is exposed. The lower drum 22B is provided with a lead groove 23 so that the magnetic tape 28 is wound around the drum 22 at a predetermined inclination angle, and the magnetic tape 28 has a flange 29b of the inlet tape guide roller 29 and the outlet tape guide roller 32. Positioning is performed by being sandwiched by the lead grooves 23, 32b and 32b, so that stable traveling is achieved.

(Problems to be solved by the invention) By the way, in the conventional configuration shown in FIG. 11 and FIG. 12, the drum 22 of the rotary head assembly 21 has the upper drum 22A.
Since it has a two-stage structure including the lower drum 22B and the lower drum 22B, the height needs to be at least twice the width of the magnetic tape 28, which has a drawback that the device cannot be downsized.

In addition, since the rotary head assembly 21 is mounted so as to be inclined, a storage space is further required, which also has a drawback that the device cannot be downsized.

It should be noted that the height positions of the entrance tape guide roller 29, the entrance inclination guide 30, the exit inclination guide 31, and the exit tape guide roller 32 in the state where the magnetic tape 28 is wound around the drum 22 are relatively displaced. Although the inclination angle of the rotary head assembly 21 can be made smaller by using the rotary head assembly 21, the entrance tape guide roller 29, the entrance tilt guide 30, the exit tilt guide 31, the exit tape guide roller 32, and the pinch roller.
Since 34 has to move a predetermined track in order to pull out the magnetic tape 28 from the initial tape position a in the tape cassette 27 to the position shown in the figure, when the moving track is not in the same plane, its mechanism is very It is not practical because it becomes complicated and technically difficult.

(Means for Solving Problems) The present invention has been proposed in view of the above points, and an object of the present invention is to simplify and downsize the configuration of the rotary head assembly itself, and to provide a tape guide. Another object of the present invention is to provide a rotary head assembly in which other mechanisms such as rollers can be easily designed and the number of parts can be significantly reduced.

That is, in order to achieve the above-mentioned object, the present invention corrects the curved surface on which the magnetic tape runs and the distortion of the waveform of the head trace that enables the magnetic head to record or reproduce in a predetermined format on the magnetic tape. And a fixed tape winding drum having a curved portion for positioning one end of the magnetic tape and having a head passage hole on the curved surface, and a slant on the back side of the curved surface. A head rotating plate having a magnetic head disposed on the circumference thereof exposed from the head passage hole; and one or more tape pushers for pressing the magnetic tape against the curved line of the flange portion. The feature is a rotating head assembly that is a feature.

Also, the tape push is made to face the curved valley of the flange, the surface of the tape push that contacts the magnetic tape is formed into an R shape, and the tape push is elastic on the tape winding drum. It is also characterized in that the tape winding drum is divided into two parts with the head passage hole as a boundary.

(Operation) In the present invention, the magnetic tape is not obliquely wound around the drum as in the prior art to perform recording and reproduction by rotating a part of the drum, but the magnetic tape is attached to the tape winding drum fixed in two. The magnetic head of the head rotating plate that is run in parallel and is inclined is brought into contact with the magnetic tape through the head passage hole provided in the tape winding drum, and the height of the rotating head assembly is reduced, and the magnetic tape By running the tapes in parallel, the mechanism for winding the magnetic tape around the tape winding drum is simplified. Also, when the magnetic tape runs in an elliptic cylinder and the magnetic head rotates and traces in an oblique state, the trace on the magnetic tape does not become a straight line when the magnetic tape is developed on a flat surface, but a wavy distortion. However, in the present invention, the magnetic tape is deformed into a wave shape by the curve of the flange portion of the tape winding drum and the tape pressing, and the distortion can be corrected within the allowable range at the time of recording and reproducing.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

1 to 4 show an embodiment of the rotary head assembly of the present invention. FIG. 1 is a perspective view of the rotary head assembly, FIG. 2 is an exploded perspective view thereof, and FIG. FIG. 4 is a diagram showing a state of being incorporated in an audio tape recorder or the like, and FIG. 4 is a diagram of a main part viewed from the direction of an arrow A in FIG.

In FIGS. 1 and 2, reference numeral 2 is a tape winding drum on which a magnetic tape runs, and the tape winding drum 2 is composed of an upper drum 2A and a lower drum 2B, and a lower end of the lower drum 2B. Is a magnetic curve that corrects the distortion of the locus traced by the magnetic head 8 when one end of the magnetic tape is positioned and the magnetic tape travels on the curved surface of the tape winding drum 2 during reproduction and reproduction. A flange 4 is formed on the tape sliding surface, and the upper drum 2A and the lower drum are
The head passage hole 3 is formed on the curved surface on which the magnetic tape runs in a state of being combined with 2B. Also,
As will be described later, the correction curve formed on the flange portion 4 has a waveform (smoothness) on the entire tape sliding contact surface, and the adhesiveness deteriorates at the valley portion. Therefore, a magnetic tape is attached to the upper end of the upper drum 2A. One or more tape pushers 20 are provided opposite the valley of the curve so as to follow the curve. On the other hand, in the tape winding drum 2, a head rotating plate 7 having a magnetic head 8 arranged on the circumference is obliquely arranged so that the magnetic head 8 is exposed from the head passage hole 3 of the tape winding drum 2. Has become. The curved surface of the tape winding drum 2 on which the magnetic tape runs has a substantially elliptical planar shape because the head rotating plate 7 rotates in a tilted state. Further, in the case of applying to a normal digital audio tape recorder or the like, it is necessary to expose the magnetic head 8 over an angle of about 90 °, so it is not possible to incorporate the head rotating plate 7 after the tape winding drum 2 is assembled. Therefore, the tape winding drum 2 can be disassembled into two members (the upper drum 2A and the lower drum 2B) with the head passage hole 3 as a boundary. However, the tape winding drum 2 may be integrally formed as long as the exposed angle of the magnetic head 8 is small and the head rotating plate 7 can be easily incorporated later. The curved surface of the tape winding drum 2 on which the magnetic tape runs can be processed with sufficient accuracy by an NC machine tool or the like, but if it is divided into two parts, it must be disassembled once in order to incorporate the head rotating plate 7. , Hole 6A, 6
A taper pin or the like is driven into B and is processed in a state in which it is screwed in the screw holes 5A and 5B, and positioning is again performed by the taper pin or the like in the disassembled assembly, thereby preventing a decrease in accuracy. On the other hand, 9 is the motor shaft, 10
Is a motor unit (motor or pulley), and these constitute the rotary head assembly 1.

FIG. 3 shows a state in which the rotary head assembly 1 shown in FIG. 1 is incorporated in a digital audio tape recorder or the like, and the magnetic tape 12 pulled out from the tape cassette 11 is the inlet tape guide roller 13 and the rotary head assembly 1. Then, it returns to the tape cassette 11 again via the outlet tape guide roller 14, the capstan shaft 15, and the pinch roller 16. Incidentally, in order to facilitate the tape running, an inlet inclination guide and an outlet inclination guide may be used as shown in FIG. 11 if necessary. Further, FIG. 4 is a view of the main part viewed from the direction of the arrow A in FIG. 3, and 17 is a frame,
Reference numerals 18 and 19 denote magnets and coils of the motor unit 10, respectively.

Therefore, when the tape cassette 11 is set in a digital audio tape recorder or the like, the magnetic tape 12
Is in the initial position a, and the inlet tape guide roller 13, the outlet tape guide roller 14, and the pinch roller 16 are the magnetic tape 12
The wire is wound around the rotary head assembly 1 by moving in the same plane from the inside to the position shown in the figure. The magnetic tape 12 is sandwiched between the capstan shaft 15 and the pinch roller 16 and runs on the curved surface of the rotary head assembly 1 at a constant speed, and the magnetic head 8 moves at high speed along the head passage hole 3 provided on the curved surface. The signal is recorded and reproduced by moving.

By the way, FIG. 5 shows a locus of a head trace of the magnetic head 8 on the magnetic tape 12 developed in a plane. F is a standard format, but the magnetic head 8 is a circle in a tilted state. Since the magnetic tape 12 moves on the circumference, when the magnetic tape 12 is simply run in parallel, the locus of the head trace becomes distorted like F '. It should be noted that the figure shows the strain with considerable emphasis, and the deviation is a minute amount of about 0.05 mm. Therefore, in the present invention, a curved line for correction is formed on the flange portion 4 of the lower drum 2B in the widthwise direction of the magnetic tape 12 to correct it, and the magnetic tape 12 is flanged by one or more tape pushers 20. By closely contacting the portion 4, the distortion of the locus of the head trace is corrected. That is, a displacement corresponding to the difference between the standard format F and the distorted format F'is applied to the flange portion 4 as a vertical undulation, and the magnetic tape 12 is brought into contact with the magnetic head 8 in a distorted state. Record so as to cancel the distortion and match the standard format F,
It is possible to reproduce.

Note that when performing only playback, the signals received by the magnetic head can be re-aligned using an IC with memory capacity, so it is possible by correcting a part of the alignment required. There are some cases.

FIG. 6 emphasizes the displacement in the width direction of the magnetic tape 12 in the running state. The magnetic tape 12 has a flange 13b of the entrance tape guide roller 13, a tape push 20 and a flange 14b of the exit tape guide roller 14. By the above, it is pressed against the flange portion 4, and the vehicle runs with a slight amount of distortion in the width direction. The curve C of the flange portion 4
The magnetic tape 12 tends to float in the valley portion of the tape because it tends to run linearly.
There are more than 20 tape pushers.

7 and 8 show a specific example of the tape pressing 20, in which (a) is a perspective view and (b) is a sectional view taken along line XX in (a). Then, in FIG. 7, the tape pushing piece 20a is viscoelastically fixed to the upper drum 2A by two screws 20b and two springs 20c for preventing resonance by attaching rubber or the like. Since the tape pushing piece 20a can finely move in the width direction and the running direction of the magnetic tape, the adjustment per tape is automatically performed. Also, in FIG. 8, one or more screws 20b
The tape pressing piece 20a is viscoelastically fixed to the upper drum 2A by means of a leaf spring 20d for preventing resonance by attaching rubber etc., and the tape is pushed downward only by the spring pressure of the leaf spring 20d. The piece 20a is pressed. In addition, in both of FIG. 7 and FIG.
The side of the a that contacts the magnetic tape is molded into an R shape,
It has a structure that does not damage the magnetic tape.

Although the above embodiment has described the case where the flange portion 4 is provided on the lower end of the lower drum 2B, the flange portion 4 is provided on the upper side of the tape winding drum 2 and one or more tape pressing members are provided in accordance with this. 20, entrance tape guide roller 1
3. The flanges 13b and 14b of the outlet tape guide roller 14 may be on the lower side.

Next, FIGS. 9 and 10 show a second embodiment of the present invention. FIG. 9 is a perspective view of a rotary head assembly, and FIG. 10 is a state where it is incorporated in a digital audio tape recorder or the like. FIG.

In FIG. 9, reference numeral 2 denotes a tape winding drum on which the magnetic tape travels, only the portion in contact with the magnetic tape is shown, and the rear shape does not hinder the rotation of the head rotating plate 7. It is optional. Further, one end of the magnetic tape is positioned on the tape winding drum 2, and a curved surface for correcting the distortion of the locus traced by the magnetic head 8 when the magnetic tape travels on the curved surface of the tape winding drum 2 is formed. A flange portion 4 having a sliding contact surface is formed, and the lower end portion is fixed to the frame by mounting screws 5 and 6. Further, one or more tape pushers 20 are provided on the upper end of the tape winding drum 2 for bringing the magnetic tape into close contact with the flange portion 4.

Further, a head passage hole 3 is formed on the curved surface of the tape winding drum 2 on which the magnetic tape runs, and on the back side of the curved surface of the tape winding drum 2, there is provided a head rotating plate 7 having a magnetic head 8 arranged on the circumference. The magnetic head 8 is arranged obliquely and is exposed from the head passage hole 3 of the tape winding drum 2. The curved surface in the vicinity of the head passage hole 3 of the tape winding drum 2 rotates in a state where the head rotating plate 7 is inclined, and thus the plane shape thereof is almost a part of an ellipse. Further, since the head rotating plate 7 is provided at a steep angle, the ratio of the exposed angle of the magnetic head 8 to the entire circumference of the head rotating plate 7 is small. Therefore, when the tape winding drum 2 is integrally formed. But it can be assembled. That is, when the exposed angle of the magnetic head 8 is large, the tape winding drum 2 must be divided into two members with the head passage hole 3 as a boundary, but such consideration is not necessary in the second embodiment. .
The curved surface of the tape winding drum 2 on which the magnetic tape runs can be processed with sufficient accuracy by an NC machine tool or the like. On the other hand, 9 is a motor shaft, and 10 is a motor portion (motor or pulley), and these constitute the rotary head assembly 1.

FIG. 10 shows a state in which the rotary head assembly 1 of FIG. 9 is incorporated in a digital audio tape recorder or the like. The magnetic tape 12 pulled out from the tape cassette 11 is the inlet tape guide roller 13, the rotary head assembly 1 Then, it returns to the tape cassette 11 again via the outlet tape guide roller 14, the capstan shaft 15, and the pinch roller 16.

Therefore, when the tape cassette 11 is set in a digital audio tape recorder or the like, the magnetic tape 12
Is in the initial position a, and the inlet tape guide roller 13, the outlet tape guide roller 14, and the pinch roller 16 are the magnetic tape 12
The magnetic tape 12 to the tape winding drum 2 of the rotary head assembly 1 by moving in the same plane from the inside to the position shown in the figure.
To contact. And the magnetic tape 12 is a capstan shaft
15, It is sandwiched between pinch rollers 16 and runs on the curved surface of the rotary head assembly 1 at a constant speed, and the magnetic head 8 moves at high speed along the head passage hole 3 provided on this curved surface to record / reproduce signals. Done. Since the scanning angle of the magnetic head 8 is steeper than the angle of the normal oblique scanning, it is necessary to increase the running speed of the magnetic tape 12 accordingly. Further, the magnetic tape 12 is positioned by being sandwiched by the flange portion 4 of the rotary head assembly 1, one or more tape pushers 20 and the flanges 13b and 14b of the inlet tape guide roller 13 and the outlet tape guide roller 14 to distort. Is corrected and stable running is achieved.

(Advantages of the Invention) As described above, in the rotary head assembly of the present invention, the curved surface on which the magnetic tape runs and the wave of the head trace that enables the magnetic head to record or reproduce in a predetermined format on the magnetic tape. A fixed tape winding drum having a curved line for correcting the shape distortion and having a flange portion for positioning one end of the magnetic tape, and having a head passage hole in the curved surface, and a back side of the curved surface. A head rotating plate having a magnetic head disposed obliquely on the periphery thereof so that the magnetic head is exposed from the head passage hole; and one or more tape pushers for pressing the magnetic tape against the curved line of the flange portion. (A) The height of the tape winding drum can be set to the width of the magnetic tape plus the thickness of the flange and mounting part. Can be achieved miniaturization of the apparatus to reduce the height of the rotary head assembly is not necessary to provide inclined as come.

(B) After the magnetic tape is pulled out from the tape cassette, it travels in substantially the same plane without changing the direction, so the mechanism for winding the magnetic tape around the tape winding drum is simple, and the design and manufacturing of the device is easy. It will be easy.

(C) When the rotating plate of the magnetic head is inclined as in the present invention, the locus of rotation of the magnetic head with respect to the magnetic tape is an elliptical orbit when viewed from above. The recording pattern of the magnetic tape recorded by this magnetic head is S-shaped, and there is no problem in recording and reproducing with the same model, but since it is different from the predetermined format defined by the standard, It is not compatible with conventional models that record and play in formats. Therefore, the present invention corrects the distortion of the track of the trace of the magnetic head by pressing the flange portion of the tape winding drum and one or more tapes as necessary, and, for example, a predetermined value defined by the standard recorded in the conventional model. Recording in a linear format becomes a waveform by the flange portion of the present invention, and can be reproduced by a model using the present invention. Further, when the magnetic tape is forced into a waveform by the flange portion and recorded on the magnetic tape by the obliquely provided magnetic head as in the invention of the present application, if the waveform is forced into a waveform, the magnetic tape conforms to the standard. The recording is the same as the defined format, and reproduction with the above-mentioned conventional model can be performed without any problem, and there is complete compatibility.

And so on.

[Brief description of drawings]

1 to 4 show a rotary head assembly according to a first embodiment of the present invention. FIG. 1 is a perspective view of the rotary head assembly, FIG. 2 is an exploded perspective view thereof, and FIG. Is a diagram showing a state of being incorporated in a digital audio tape recorder or the like, FIG. 4 is a diagram of a main part seen from the direction of an arrow A in FIG. 3, and FIG. 5 is an explanatory diagram of a trace of a head trace,
FIG. 6 is an explanatory view of the running state of the magnetic tape, FIGS. 7 and 8 are configuration diagrams showing a concrete example of tape pushing, and FIGS. 9 and 10 show a second embodiment of the present invention. Is something
FIG. 9 is a perspective view of a rotary head assembly, FIG. 10 is a view showing a state where the rotary head assembly is incorporated in a digital audio tape recorder, and FIGS. 11 and 12 are configuration diagrams of a conventional rotary head assembly. 1 ... Rotating head assembly, 2 ... Tape winding drum, 2A ... Upper drum, 2B ... Lower drum, 3 ... Head passage hole, 4 ... Flange portion, 5A, 5B ... Screw hole, 6A, 6B ……
Hole, 5,6 ... Mounting screw, 7 ... Head rotating plate, 8 ... Magnetic head, 9 ... Motor shaft, 10 ... Motor part, 11 ... Tape cassette, 12 ... Magnetic tape, 13 ... Inlet tape guide roller, 13a …… Roller, 13b …… Flange, 14 ……
Exit tape guide roller, 14a …… roller, 14b …… flange, 15 …… capstan shaft, 16 …… pinch roller, 17
…… Frame, 18 …… Magnet, 19 …… Coil, 20…
… Tape press, 20a …… Tape press piece, 20b …… Screw, 20
c ... spring, 20d ... leaf spring.

Claims (5)

[Scope of utility model registration request] 1. A curved surface on which a magnetic tape runs, and a wavy curve for compensating for a wavy distortion of a head trace that enables recording or reproduction in a predetermined format on the magnetic tape by a magnetic head. And a fixed tape winding drum having a flange portion for positioning one end of the magnetic tape and having a head passage hole on the curved surface, and a magnetic tape provided obliquely on the back side of the curved surface and arranged on the circumference. A rotary head assembly comprising: a head rotating plate having a head exposed from the head passage hole; and one or more tape pressing members for pressing the magnetic tape against the curved line of the flange portion. 2. The rotary head assembly according to claim 1, wherein the tape push is provided so as to face the valley of the curved portion of the flange portion. 3. The rotary head assembly according to claim 1 or 2, wherein a surface of the tape-pressing portion in contact with the magnetic tape is formed into an R shape. 4. A utility model registration claim in which the tape push is elastically fixed on the tape winding drum.
The rotary head assembly according to item 3 or 4. 5. A utility model registration claim in which the tape winding drum is divided into two parts with a head passage hole as a boundary.
The rotary head assembly according to item (2), item (3) or item (4).