JPH0520748A - Rotary head drum device for magnetic recording and regenerating device - Google Patents

Abstract

PURPOSE:To make the rotary head drum device thin and small-sized, to make the whole magnetic recording and regenerating device thin and small-sized by cutting and forming the projecting parts of the upper and lower sides of a fixed drum. CONSTITUTION:An oblique cut surface 10f is formed by cutting the lower side projecting in the lower direction of a fixed lower drum 10 obliquely attached to the chassis 101 of a VTR 100 erecting and fixing a shaft 11. Further, an oblique cut surface 40f is formed by cutting the upper side projecting in the upper direction of a fixed upper drum 40. Thus, the rotary head drum device is thinned and miniaturized and also, the whole magnetic recording and regenerating device is thinned and miniaturized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical scan type rotary head drum device suitable for use in a VTR (video tape recorder) as a magnetic recording / reproducing device.

[0002]

2. Description of the Related Art In a VTR (video tape recorder) as a magnetic recording / reproducing apparatus, a rotary drum having a head for recording and reproducing a video signal is arranged at a slight inclination from the tape running direction, and is rotated on the magnetic tape. A helical scan type rotary head drum device for recording in an oblique pattern is used. This rotary scan type rotary head drum device is attached and fixed to a chassis of a VTR main body so as to be inclined at a predetermined angle, and has a fixed drum (lower drum) having an inclined tape lead portion on an outer peripheral surface, and the fixed portion. It consists of a rotary drum (upper drum) rotatably supported on the drum via a rotary shaft, and a pair of heads are projected on the lower surface of the rotary drum between these drums so as to project from the outer peripheral surface by a predetermined amount. It is set up.

Then, a magnetic tape is loaded from the tape cassette, for example, mounted on the VTR main body by a loading mechanism including a pull-out guide and a tilt guide disposed on the chassis on which the rotary head drum device is erected and fixed. The drum is helically wound around the outer peripheral surface of each drum, and each head is obliquely scanned with respect to the magnetic tape to sequentially form diagonal tracks.

[0004]

However, in the above rotary scan type rotary head drum device, since the fixed drum of the rotary head drum device is fixed to the chassis by inclining it, the upper end portion protruding above the rotary drum is fixed. Since the distance from to the lower end of the fixed drum projecting to the lower side of the fixed drum (chassis side) becomes long, there is a drawback that the entire height of the rotary head drum device becomes high and the size becomes large. Also,
The lower end side of the fixed drum projecting downward is attached so as to project to the rear surface side of the chassis to reduce the drum portion projecting on the chassis, but there is a drawback that the entire VTR becomes thick. It was

Therefore, according to the present invention, the upper and lower sides of the fixed upper and lower drums or the lower side of the fixed lower drum are cut to reduce the overall thickness and size of the drum and the overall thickness of the magnetic recording / reproducing apparatus. Provided is a rotary head drum device of a magnetic recording / reproducing apparatus which can be downsized.

[0006]

SUMMARY OF THE INVENTION A rotary head drum device for a magnetic recording / reproducing apparatus according to the present invention comprises a fixed lower drum, which is mounted obliquely with respect to a chassis of the magnetic recording / reproducing apparatus with its shaft vertically erected and fixed, and an outer periphery. A rotary drum rotatably supported in the middle of the shaft via a bearing by protruding a head on a surface of the shaft, a fixed upper drum fixed to the upper end of the shaft, and a rotor rotating with the rotary drum. Side rotary transformer and a stator-side rotary transformer fixed to the fixed lower drum, and the upper side protruding above the fixed upper drum and the lower side protruding below the fixed lower drum are respectively cut and molded. I am doing it.

A rotary head drum device for a magnetic recording / reproducing apparatus according to another aspect of the present invention includes a fixed lower drum which is vertically mounted and fixed on a shaft and is obliquely attached to a chassis of the magnetic recording / reproducing apparatus, and a head on the outer peripheral surface. A rotary drum rotatably supported in the middle of the shaft via a bearing by protruding a predetermined amount, a fixed upper drum fixed to the upper end of the shaft, and rotation on the rotor side rotating with the rotary drum. With a transformer
A stator-side rotary transformer fixed to the fixed lower drum, the outer peripheral side of each of the rotary transformers is formed higher than the inner peripheral side through a stepped portion, and the chassis side of the fixed lower drum is provided. The lower side, which faces the outer peripheral portion of the stator-side rotary transformer projecting to the above, is largely cut and molded up to the outer peripheral portion of the rotary transformer.

[0008]

Since the upper side projecting above the fixed upper drum and the lower side projecting below the lower fixed drum are respectively cut and molded, the rotary head drum device as a whole can be made thin and compact, and the magnetic recording / reproducing apparatus Since the lower end part of the fixed lower drum protruding to the back side of the chassis is reduced,
The magnetic recording / reproducing apparatus as a whole is made thinner and smaller.

Further, the outer peripheral side of each of the rotor side and stator side rotary transformers is formed higher than the inner peripheral side through the stepped portion, and the stator side rotary transformer protruding toward the chassis side of the fixed lower drum is provided. The lower side facing the outer periphery,
Since the outer peripheral portion of the rotary transformer is largely cut and formed, the entire rotary head drum device and the entire magnetic recording / reproducing device can be further thinned and downsized.

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a helical scan type rotary head drum device, which is used in an 8 mm VTR 100 as a magnetic recording / reproducing device, and a chassis 10 thereof.
It is attached at a predetermined angle on top of 1. The rotary head drum device 1 includes a fixed lower drum 1 in which a lower end 11a of a cylindrical fixed shaft 11 is fixed by a press fit into a hole 10b formed in the center of a bottom 10a so as to stand vertically.
0, a cylindrical bearing housing 20 rotatably supported on the middle part 11b of the fixed shaft 11 via a pair of ball bearings (bearings) 28, 28, and a head 31 projecting from the outer peripheral surface 30a by a predetermined amount. Disk-shaped rotary drum 30 fixed to the upper part of the bearing housing 20 and the fixed upper drum 4 fixed to the upper end 11c of the fixed shaft 11 and facing the rotary drum 30 with a predetermined clearance.
0, the rotor 51 fixed to the lower portion of the bearing housing 20, and the fixed lower drum 10 and a predetermined clearance (about 0.3 mm each) between the magnet 53 and the back yoke 54 of the rotor 51. Coreless motor 50 composed of a stator 56 facing each other
A video signal is supplied to the head 31 rotating at the time of recording, and a reproduction signal is taken out at the time of reproduction, on the rotor side mounted on the lower surface side of the bearing housing 20 and on the upper surface side of the bottom portion 10a of the fixed lower drum 10. The rotary transformer 60 is composed of the attached transformers 61 and 62 on the stator side.

The fixed lower drum 10 is formed in a cylindrical shape having a bottom, and a magnetic tape 1 to be described later is provided on the outer peripheral surface 10d thereof.
A tape lead portion 10c for guiding 11 is formed.
The rotating transformer 62 on the stator side is bonded and fixed to the upper surface of the bottom portion 10a of the fixed lower drum 10. further,
On the bottom surface of the bottom portion 10a of the fixed lower drum 10, a flexible substrate for external connection of the rotary transformer 62 on the stator side via a plurality of pins and a terminal plate (neither is shown).
Is installed.

As shown in FIGS. 1 and 2, upper and lower flanges 21 and 22 are integrally formed on the upper and lower portions of the bearing housing 20 so as to project therefrom. The upper flange 21 has a pair of substantially fan-shaped protrusions, and female screw holes 23 for fastening and fixing the rotary drum 30 are formed at the centers of the protrusions. The outer peripheral surface 20 a above the upper flange 21 is attached to the upper flange 21 by the rotary drum 30.
It is a centering reference plane that determines the radial position when mounting. A pair of insertion holes 24, 24 are formed in the upper flange 21 so as to sandwich the female screw holes 23. The lower flange 22 is formed in a disk shape so as to integrally project, and a pair of female screw holes 25, 25 for fastening and fixing the rotor 51 are formed at positions 90 ° apart from the positions of the female screw holes 23. There is. An outer peripheral surface 22a of the lower flange 22 serves as a centering reference surface that determines a radial position when the rotor 51 is mounted on the lower flange 22. Further, three insertion holes 26 are formed between the pair of female screw holes 25, 25 of the lower flange 22, and the notches 27 are formed on the lower side thereof.
Has been formed. A compression coil spring 29 is interposed between the pair of ball bearings 28, 28 fitted in the bearing housing 20, and the pair of ball bearings 28, 28 is loose relative to the fixed shaft 11. There is no such thing.

Further, the rotary drum 30 is formed in a circular disk shape in which a portion of the upper surface 30b excluding the outer peripheral surface 30a side is projected stepwise, and a center hole 3 is formed in the center thereof.
0d is formed. The center hole 30d of the rotary drum 30 is fitted to the outer peripheral surface 20a of the bearing housing 20, and the lower surface 30c around the center hole 30d is placed on the upper flange 21 of the bearing housing 20.
Then, the rotary drum 30 and the upper flange 21 of the bearing housing 20 are fastened and fixed via respective setscrews 32 screwed into respective female screw holes 23 formed in the upper flange 21. In addition, the lower surface 30 of the rotary drum 30
The base portion of the head base 34 is fixed to the opening recess 30e formed on the c side via a set screw 33. The head 31 is fixed to the tip end side of the upper surface of the head base 34 with an adhesive or the like. The tip side of the head base 34 is deformable downward by pressing the tip 35a of the pairing adjustment screw 35 screwed into the female screw hole 30f formed in the rotary drum 30. Adjustment).

The fixed upper drum 40 is formed in an inverted cylindrical shape in which the upper portion 40a is closed, and the center of the upper portion 40a is stepped and slightly recessed. A center hole 40c formed in the center of the upper portion 40a of the fixed upper drum 40 is press-fitted into the upper end portion 11c of the fixed shaft 11, and a flat lower surface side around the center hole 40c is fixed to the fixed shaft 1 described above.
It is mounted on an annular plate-shaped flange 41 which is press-fitted and fixed to the lower side of the upper end portion 11c of No. 1. Then, the fixed upper drum 40 and the flange 41 are fastened and fixed by respective setscrews 42 screwed into a plurality of female screw holes 41a of the flange 41. The outer peripheral surface 10d of the fixed lower drum 10
And the outer peripheral surface 30a of the rotary drum 30 and the fixed upper drum 4
0 is flush with the outer peripheral surface 40d, and the outer peripheral surfaces 10d, 30a, 40d of the drums 10, 30, 40, respectively.
Is the tape running surface of the magnetic tape 111 which is wound around each of the outer peripheral surfaces 10d, 30a, 40d by a predetermined angle and runs.

Further, as shown in FIG. 1, the upper portion of the fixed upper drum 40 (the upper right side in FIG. 1) is inclined by 20 ° from a line perpendicular to the fixed shaft 11 (a line parallel to the locus of the head 31). The (face) is formed by cutting (including the case of forming into a tapered surface at the time of forming the mold in addition to the predetermined cutting process). This diagonal cut surface is designated as 40f in FIGS. 1 and 4 and 5.
Indicate. The inclination of the cut surface 40f is determined by the drum mounting angle of the fixed lower drum 10 when the rotary head drum device 1 is mounted on the chassis 101 (the fixed shaft 1 relative to the chassis 101).
It is determined by the same angle as the drum mounting angle described above. Further, as shown in FIG. 4, the amount of cut (depth, size, etc.) is such that the fixed upper drum 40 has an inner wall 110a on the upper side of the tape cassette 110.
It is necessary to cut to an amount that does not correspond to the above, that is, an amount that the entire rotary head drum device 1 fits into the opening recess 110b at the front center of the tape cassette 110 as shown in FIGS. This means that the maximum height of the fixed upper drum 40 including the height of the head of the set screw 42 is below the upper cut line L ₁ shown in FIG.

The lower portion of the fixed lower drum 10 (see FIG. 1)
The lower left side of the middle left side is also cut and formed (including the case of forming a tapered surface at the time of molding in addition to the predetermined cutting processing) in parallel with the upper cut surface 40f of the fixed upper drum 40. There is. This oblique cut surface is indicated by reference numeral 10f in FIGS. 1 and 4 and 5, and the lower cut line is indicated by L ₂ . Accordingly, when the rotary head drum device 1 is obliquely placed on the chassis 101 (20 ° in this case), the height H in the direction perpendicular to the chassis 101 (drum height when diagonally placed) H can be lowered. it can. Further, the chassis 101 of the fixed lower drum 10 of the rotary head drum device 1
It is possible to reduce the amount of the lower end portion protruding to the back surface side of the device as much as possible. As a result, it is possible to reduce the height (thickness) of the entire VTR 100 when the rotary head drum device 1 is installed on the chassis 101.

The rotor 51 of the motor 50 comprises a disk-shaped rotor case 52, an annular plate-shaped magnet 53 fixed to the upper surface of the rotor case 52, and a disk-shaped back yoke 54. It is fastened and fixed to each female screw hole 25 of the lower flange 22 of the housing 20 via a set screw 55. As shown in FIGS. 2 and 3, a mounting hole 52a through which the upper flange 21 of the bearing housing 20 is inserted is formed in the center of the rotor case 52, and an annular recess 52b is formed on the bottom surface thereof. . This recess 5
The peripheral surface 52c of 2b serves as a reference surface fitted to the centering reference surface 22a of the lower flange 22 of the bearing housing 20, and as shown in FIG. 3, a pair of lower surfaces 52d, 52d protruding inwardly. Are mounting surfaces. A hole portion 52d 'through which the shank portion of each set screw 55 is inserted is formed in each mounting surface 52d. Each of the mounting surfaces 52d is a surface that comes into contact with the upper surface of the lower flange 22, and is higher than the lower surface of the other recess 52b by a step of about 50 μm.

The back yoke 54 of the rotor 51 is provided with a pair of back yoke supports 59, 59 provided 180 degrees apart on the outer peripheral surface 20b between the upper and lower flanges 21, 22 of the bearing housing 20. 20b so that the gap does not change with reference to 20b.
Installed on. The back yoke 54 is made of a damping material having a three-layer structure in which resin is sandwiched between metal plates. Also,
The back yoke support 59 is made of polyester elastomer resin, rubber or the like having a high vibration damping effect.

The stator 56 of the motor 50 is composed of a disk-shaped stator substrate 57 and a plurality of layers of coil portions 58 and the like provided on the lower surface of the stator substrate 57, and the outer peripheral portion 57a of the stator substrate 57 is formed. The fixed lower drum 10
It is adhered and fixed to the step portion 10e formed in the inner peripheral surface of the peripheral wall portion with an adhesive. The coil portions 58 of multiple phases of the stator 56 face the magnet 53 of the rotor 51 with a predetermined clearance (about 0.3 mm).

Further, the rotary transformer 61 on the rotor side is adhered and fixed to the lower surface of the lower flange 22 of the bearing housing 20 with an adhesive or the like, and the fixed lower drum 10
It faces the rotary transformer 62 on the stator side fixed to the upper surface of the bottom portion 10a with a predetermined gap (for example, 25 μm). Further, the wiring (not shown) of the rotary transformer 61 on the rotor side includes the notch portion 27 of the lower flange 22 of the bearing housing 20 and the insertion holes 26 to the upper flange 21.
It is connected to a relay board (not shown) fixedly attached to the upper surface 30b of the rotary drum 30 through each of the insertion holes 24, and is connected to the recording / reproducing head 31 on the head base 34 via the relay board.

FIG. 5 shows a tape path system (M loading system) of the VTR 100. In the figure, reference numeral 102 is a capstan shaft, 103 is a pinch roller, 104 and 105 are inclined guides, and 106 and 107 are drawn out. Be a guide.

According to the rotary head drum device 1 of the above embodiment, the lower left lower end side of the fixed lower drum 10 and the upper right upper end side of the fixed upper drum 40 are slanted so as to be parallel to the upper surface of the chassis 101. Since the rotary head drum device 1 is cut into two, the height H can be reduced when the rotary head drum device 1 is obliquely placed on the chassis 101, and the rotary head drum device 1 as a whole can be made thin and compact. Further, as shown in FIG. 4, since the amount of the lower end portion of the fixed lower drum 10 of the fixed lower drum 10 of the rotary head drum device 1 protruding to the back surface side of the chassis 101 can be reduced, the lower portion of the chassis 101 can be reduced. The thickness of the side can also be reduced,
It is also possible to reduce the thickness and size of the VTR 100 as a whole.
Therefore, the maximum height H of the rotary head drum device 1 is defined by the cut surfaces 10f and 40f of the drums 10 and 40 in the mounted state, and the cut surfaces 10f and 40f are on the upper surface of the chassis 101. Since they are parallel to each other, the height relationship between the tape cassette 110 and the rotary head drum device 1 is always constant with respect to the chassis 101 even if they move in parallel. The maximum height H of the rotary head drum device 1 is the inner wall 110a on the upper side of the tape cassette 110 mounted on the chassis 101.
Since it is lower than the above, the rotary head drum device 1 can enter the opening concave portion 110b at the front center of the tape cassette 110. That is, when M-loading the magnetic tape 111 from the opening recess 110b of the tape cassette 110 to the rotary head drum device 1, the tape cassette 110
Can be horizontally moved with respect to the rotary head drum device 1, and the rotary head drum device 1 can be inserted into the tape cassette 110 in a loading completed state.

Further, since the outer peripheral portion 57a of the stator substrate 57 of the stator 56 of the motor 50 incorporated between the fixed lower drum 10 and the rotary drum 30 is fixed to the stepped portion 10e of the fixed lower drum 10 with an adhesive or the like. Therefore, the rigidity of the stator 56 can be increased and the vibration of the stator 56 due to the rotation of the rotor 51 of the motor 50 can be damped. further,
Back yoke 54 that rotates with the rotor case 52
Is formed of a vibration damping material in which a resin plate is sandwiched between steel plates, and the back yoke support 59 for supporting the back yoke 54 is formed of a material having a high vibration damping property such as polyester elastomer. Can also be attenuated. As a result, when the motor 50 rotates, the stator 5
6 and the back yoke 54 can be suppressed,
The electromagnetic noise of the motor 50 due to these vibrations can be reliably suppressed.

By adopting such a structure of the motor 50, when assembling the motor 50 and the like, as shown in FIG. 2, the rotor case 52 of the rotor 51 is passed through without hitting the upper flange 21 of the bearing housing 20. It can be attached to the lower flange 22, and the upper flange 21 and the magnet 53 can be increased in size. In addition, the lower flange 2 of the bearing housing 20
When the rotor case 52 of the rotor 51 is attached to the rotor 2, the outer peripheral surface 22a of the lower flange 22 is used as a centering reference surface and the recess 52b formed on the lower surface side of the rotor case 52 is fitted into the rotor case 52. Highly accurate assembly can be performed at a cost.

The wiring (not shown) extending from the rotary transformer 61 on the rotor side is provided with the notches 27 formed in the lower flange 22 of the bearing housing 20 and the insertion holes 2.
6 can be easily routed to the lower surface 30c side of the rotating drum 30 from the respective insertion holes 24 formed in the upper flange 21. Further, a relay board or the like (not shown) that connects the rotary transformer 61 and the head 31 via the wiring can be arranged on the rotary drum 30, and the overall height of the rotary head drum device 1 can be further reduced. It is possible,
From this point as well, it is possible to further reduce the thickness, size, and weight of the rotary head drum device 1 as a whole.

FIG. 6 shows a rotary head drum device 1'of another embodiment. The outer peripheral portion 6 of each of the rotary transformers 61 and 62 on the rotor side and the stator side of the rotary head drum device 1 '.
The outer circumference of the stator side rotary transformer 62 is formed so that the sides 1a and 62a are higher than the inner peripheral portions 61b and 62b through the stepped portions 61c and 62c, and protrudes toward the chassis side of the VTR of the fixed lower drum 10. The lower side facing the portion 62a is largely cut and molded to the outer peripheral portion 62a of the rotary transformer 62. The other structure is similar to that of the above-described embodiment, and therefore, the same reference numerals are given and detailed description thereof is omitted. As a result, the height H of the rotary head drum device 1'can be made lower than that of the above-described embodiment, and the lower left lower VTR of the fixed lower drum 10 has almost no portion projecting to the rear surface side of the chassis. The VTR as a whole can be made even thinner.

In each of the above-mentioned embodiments, a so-called propeller rotating type rotary head drum device in which the rotary drum is a disk has been described, but the rotary drum can be applied to a medium drum rotary type rotary head drum device having a substantially cylindrical shape. Of course, the other embodiments can be applied to the cutting of the lower end of the fixed drum of the rotary upper drum type.

[0029]

As described above, according to the rotary head drum device of the present invention, the fixed lower drum, which is fixed obliquely to the chassis of the magnetic recording / reproducing apparatus with the shaft vertically standing and fixed, and the outer peripheral surface. A rotary drum rotatably supported in the middle of the shaft through a bearing by projecting the head by a predetermined amount, a fixed upper drum fixed to the upper end of the shaft, and a rotor side rotating with the rotary drum. A rotating transformer,
A rotary transformer fixed to the fixed lower drum is provided on the stator side, and the upper side projecting above the fixed upper drum and the lower side projecting below the fixed lower drum are formed by cutting, respectively. The entire magnetic recording / reproducing apparatus can be made thin and compact because it is possible to reduce the thickness and size of the entire magnetic recording / reproducing apparatus, and to reduce the lower end portion of the fixed lower drum protruding to the back side of the chassis of the magnetic recording / reproducing apparatus. You can

Further, the outer peripheral side of each of the rotor side and stator side rotary transformers is formed higher than the inner peripheral side via the stepped portion, and the stator side rotary transformer protruding toward the chassis side of the fixed lower drum. Since the lower side facing the outer peripheral portion of the rotary transformer is largely cut and molded to the outer peripheral portion of the rotary transformer, the entire rotary head drum device and the magnetic recording / reproducing device can be made even thinner and smaller.

[Brief description of drawings]

FIG. 1 is a sectional view of a rotary head drum device showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a relationship between a rotor and a bearing housing of a motor used in the rotary head drum device.

FIG. 3 is a perspective view of the rotor seen from the bottom side.

FIG. 4 is a schematic side view of a VTR using the rotary head drum device.

FIG. 5 is a schematic plan view of a VTR using the rotary head drum device.

FIG. 6 is a sectional view of a rotary head drum device according to another embodiment.

[Explanation of symbols]

1, 1 '... rotary head drum device, 10 ... fixed lower drum, 10f ... cut surface, 11 ... shaft, 11b ... midway part, 1
1c ... upper end part, 28 ... ball bearing (bearing), 30
... rotating drum, 30a ... outer peripheral surface, 31 ... head, 40 ...
Fixed upper drum, 40f ... Cut surface, 61 ... Rotation transformer on rotor side, 61a ... Outer peripheral portion, 61b ... Inner peripheral portion, 61c
... stepped portion, 62 ... stator side rotary transformer, 62a ...
Outer peripheral portion, 62b ... Inner peripheral portion, 62c ... Stepped portion, 100 ... V
TR (Magnetic Recording / Reproducing Device), 101 ... Chassis.

Claims (2)

[Claims] 1. A fixed lower drum which is vertically fixed to a shaft and obliquely attached to a chassis of a magnetic recording / reproducing apparatus, and a head which protrudes from an outer peripheral surface by a predetermined amount, and a bearing is provided at a middle portion of the shaft. Rotating drum that is rotatably supported, a fixed upper drum that is fixed to the upper end of the shaft, a rotor-side rotation transformer that rotates together with the rotating drum, and a stator-side rotation that is fixed to the fixed lower drum. A rotary head drum device for a magnetic recording / reproducing apparatus, comprising: a transformer; and an upper side projecting above the fixed upper drum and a lower side projecting below the fixed lower drum, respectively, being cut and formed. 2. A fixed lower drum, which is vertically fixed to a shaft and obliquely attached to a chassis of a magnetic recording / reproducing apparatus, and a head is protruded from an outer peripheral surface by a predetermined amount, and a bearing is provided at a middle portion of the shaft. Rotating drum that is rotatably supported, a fixed upper drum that is fixed to the upper end of the shaft, a rotor-side rotation transformer that rotates together with the rotating drum, and a stator-side rotation that is fixed to the fixed lower drum. An outer peripheral portion of each rotary transformer, the outer peripheral portion of which is formed higher than the inner peripheral portion through a stepped portion, and the outer peripheral portion of the stator-side rotary transformer which protrudes toward the chassis of the fixed lower drum. A rotary head drum device of a magnetic recording / reproducing apparatus, characterized in that a lower side facing to is greatly cut and formed to the outer peripheral portion of the rotary transformer.