JPH10334431A - Rotary magnetic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary magnetic recording device assembled accurately and easily at low costs. SOLUTION: This device is provided with upper and lower drums 11 and 12 having cylindrical outer peripheral surfaces and arranged to be fixed, a middle drum 14 supported rotatably in a hollow part between the upper and lower drums 11 and 12, at least one magnetic head 15 attached to be protruded to the outside from a gap between the upper and lower drums 11 and 12 in the peripheral edge of the middle drum 14 and a rotating means 18 for rotary- driving the middle drum 14. In this case, a supporting shaft 13 for rotatively supporting the middle drum 14 is held to be fixed in the upper and lower drums 11 and 12, and the middle drum 14 is supported rotatably by the supporting shaft 13 via a bearing 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary magnetic recording apparatus used in a helical scan type magnetic recording / reproducing apparatus such as a VTR and a DAT.

[0002]

2. Description of the Related Art Conventionally, a rotary magnetic recording apparatus is, for example, shown in FIG.
It is configured as shown in FIG. In FIG. 5, a rotary magnetic recording apparatus 1 includes an upper drum 2 and a lower drum 3 as fixed drums having cylindrical outer peripheral surfaces aligned with each other, and a rotating drum in a hollow portion defined by these two drums 2 and 3. And a middle drum 4 arranged as possible. At least one magnetic head 5
However, it is attached so that the tape contact surface protrudes outside from between the upper drum 2 and the lower drum 3.

[0003] The upper drum 2 and the lower drum 3 are fixedly arranged, and the upper drum 2 is supported by a support member 6 with respect to the lower drum 3. The rotating shaft 7 integrally mounted on the middle drum 4 is rotatably supported on the lower drum 3 by a bearing 7a.

The rotating shaft 7 is driven to rotate at a high speed by a motor 8 provided at a lower end thereof.
Here, the motor 8 includes a stator 8 a having a coil fixedly arranged on the lower surface of the lower drum 3, and a rotor 8 b having a rotor magnet attached to a lower end of the rotating shaft 7.

[0005] Further, the magnetic head 5 is provided through a rotary transformer 9 provided in a region around the rotating shaft 7.
Signals are input and output between the outside and the outside. The rotary transformer 9 includes a rotor 9a attached to the middle drum 4 and a stator 9b attached to the lower drum 3.

According to the rotary magnetic recording apparatus 1 having such a configuration, the rotating shaft 7 is driven to rotate by the rotation of the motor 8. Accordingly, the middle drum 4 is driven to rotate at a high speed, and the magnetic tape runs along the tape leads (not shown) of the upper drum 2 and the lower drum 3. Thus, the magnetic head 5 provided on the peripheral edge of the middle drum 4 moves relatively obliquely with respect to the magnetic tape, and records or reproduces a magnetic signal on or from the magnetic tape.

[0007]

However, in the rotary magnetic recording apparatus 1 having such a structure, the supporting member 6 is temporarily fixed to the lower drum 3 before assembling. 2 is attached to the fixing portion 6a of the support member 6. Then, after adjusting the coaxiality and the inclination of the upper drum 2 and the lower drum by, for example, applying a probe of an electric micrometer to the side surface of the upper drum 2, the lower drum 3
, The supporting member 6 is fixed.

Accordingly, in order to fix and hold the upper drum 2 with respect to the lower drum 3, a support member 6 is required,
The support member 6 needs to ensure the parallelism of the mounting surface to the upper drum 2 and the lower drum 3 for each component. At the time of assembly, it is necessary to adjust the coaxiality between the upper drum 2 and the lower drum 3 and the inclination. Thus, the number of parts increases, assembling becomes complicated, and the processing accuracy and assembling accuracy of the parts are required, so that there is a problem that the parts cost and the assembling cost increase.

The present invention has been made in view of the above points, and has a low cost.
It is an object of the present invention to provide a rotating magnetic recording device that can be easily and accurately assembled.

[0010]

SUMMARY OF THE INVENTION According to the present invention, there is provided, in accordance with the present invention, an upper drum, a lower drum, a middle drum rotatably supported between the upper drum and the lower drum; At least one magnetic head attached to the periphery so as to protrude outward from a gap between the upper drum and the lower drum, and a middle drum that is driven to rotate around a support shaft, wherein the middle drum is provided. Rotary magnetic recording, wherein a support shaft for rotatably supporting is fixedly held to an upper drum and a lower drum, and a middle drum is rotatably supported to the support shaft via a bearing. This is achieved by the device.

According to the above configuration, the upper drum is fixedly held to the support shaft fixed to the lower drum, so that the upper drum is fixedly held to the lower drum via the support shaft. . For this reason, there is no need for a support member for fixing the upper drum to the lower drum as in the case of the conventional rotary magnetic recording apparatus having a rotatable rotating shaft. Therefore, the need for a support member that requires processing accuracy and assembly accuracy is unnecessary, so that the number of parts can be reduced, and adjustment of coaxiality and inclination between the upper and lower drums is not required, and component costs and assembly costs are reduced. Costs will be reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. still,
Since the embodiments described below are preferred specific examples of the present invention, various technically preferred limitations are added.
The scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

FIG. 1 shows a first embodiment of a rotary magnetic recording apparatus according to the present invention. In FIG. 1, a rotating magnetic recording apparatus 10 includes an upper drum 11 and a lower drum 12 as fixed drums having cylindrical outer peripheral surfaces aligned with each other.
And a middle drum 14 as a rotating drum rotatably disposed around a support shaft 13 in a hollow portion defined by these two drums 11 and 12. At least one magnetic head 15 (two on both sides in the illustrated case) is provided on the periphery of the middle drum 14 such that the tape contact surface thereof projects outside from between the upper drum 11 and the lower drum 12. Installed.

The upper drum 11 and the lower drum 12 are fixedly arranged, and are supported as follows.
3 are fixedly held to each other. Here, the lower end of the support shaft 13 is fixed to the lower drum 12 by press fitting or shrink fitting. The support shaft 13
Does not rotate.

The middle drum 14 is rotatably supported by a support shaft 13 fixedly arranged as described above via a bearing (a ball bearing in the illustrated case) 16. Further, in the case shown, near the upper end of the support shaft 13,
A preload ring 17 is provided.
Thus, the support shaft 13 applies a preload to the bearing 16. Further, the upper end of the support shaft 13 is fixed to the upper drum 11 by press fitting or shrink fitting.

The middle drum 14 is driven to rotate at a high speed by a motor 18 provided near the lower end thereof. Here, the motor 18 has a configuration known per se, and includes a stator 18 a having a coil fixedly disposed on the upper surface of the lower drum 12, and a middle drum 18 opposed to the stator 18 a in the axial direction. And a rotor 18b having a rotor magnet provided at a lower end of the rotor 14.

Further, the magnetic head 15 is mounted on the support shaft 1.
Signals are input and output to and from the outside via a rotary transformer 19 provided in a region around 3 and a head amplifier (not shown). The rotary transformer 19 has a known structure per se, and includes a rotor 19a attached to the outer peripheral surface of the middle drum 14 and a stator 19b attached to the lower drum 12 side. As a result, the rotor 19 on the magnetic head 15 side
a and the stator 19b on the device body side exchange signals in a non-contact manner.

The rotating magnetic recording apparatus 10 according to the present embodiment
Is configured as described above, and the motor 18
The middle drum 14 is driven to rotate at a high speed, and the magnetic tape runs along tape leads (not shown) of the upper drum 11 and the lower drum 12. Thereby, the magnetic head 1 provided on the peripheral edge of the middle drum 14 with respect to the magnetic tape
5 moves relatively obliquely to record and / or reproduce signals on the magnetic tape.

When assembling the rotary magnetic recording apparatus 10, the lower end of the support shaft 13 is attached to the lower drum 12 by press-fitting or shrink fitting. Then, the middle drum 14 in which the magnetic head 15, the rotor 18b of the motor 18, the rotor 19a of the rotary transformer 19, and the bearing 16 (in the illustrated case, the outer ring of a ball bearing) is inserted into the support shaft 13 is inserted. . Next, the preload ring 17 is fixed to the support shaft 13 while applying a constant load. As a result, a predetermined preload is applied to the support shaft 13. Thereafter, the upper drum 11 is inserted into the upper end of the support shaft 13 and attached to the preload ring 17 by screwing or the like.

In this case, the positioning of the upper drum 11 with respect to the lower drum 12 is basically performed by the support shaft 13 and the upper drum 11.
No special adjustment work is required because it is determined by the fitting accuracy between the shaft hole 11a and the inner diameter of the shaft hole 11a. The upper and lower ends of the support shaft 13 are fitted to the upper drum 11 and the lower drum 12 in accordance with the required accuracy for the rotary magnetic recording apparatus 10, for example, by clearance fitting such as screwing, shrink fitting, press fitting, and the like. The interference fit is appropriately selected.

As described above, according to the above embodiment, the upper drum is fixedly held to the upper end of the support shaft having the lower end fixed to the lower drum.
It will be fixedly held to the lower drum. For this reason, there is no need for a support member for fixing the upper drum to the lower drum as in the case of the conventional rotary magnetic recording apparatus having a rotatable rotating shaft. Therefore, the need for a support member that requires processing accuracy and assembly accuracy is unnecessary, so that the number of parts can be reduced, and adjustment of coaxiality and inclination between the upper and lower drums is not required, and component costs and assembly costs are reduced. Costs will be reduced.

FIG. 2 shows a second embodiment of the rotary magnetic recording apparatus according to the present invention. 2, the rotary magnetic recording device 20 has substantially the same configuration as the rotary magnetic recording device 10 shown in FIG. 1, except that the preload ring 17 is omitted and the upper end of the support shaft 13 is attached to the upper drum 11. On the other hand, the configuration is different only in that it is fixed by press fitting or shrink fitting.

According to this configuration, the preload ring 17 is integrated with the upper drum 11, and the preload is directly applied to the bearing 16 from the upper drum 11. As a result, the preload ring 17 becomes unnecessary. Therefore, the number of parts is further reduced, and the cost of parts and the cost of assembly are further reduced.

FIG. 3 shows a third embodiment of the rotary magnetic recording apparatus according to the present invention. 3, the rotary magnetic recording device 30 has substantially the same configuration as the rotary magnetic recording device 10 shown in FIG. 1, but differs from the rotary magnetic recording device 10 only in that a direct bearing 31 is used instead of the bearing 16. Has become. Here, the direct bearing 31
Are configured as ball bearings, and the support shaft 13 itself is configured as an inner ring 13a.

According to this configuration, the preload is applied to the bearing (that is, the direct bearing 31) when the direct bearing 31 is mounted on the middle drum 14. Need not be added, and assembly can be performed more easily. Here, the flange portion 14a of the middle drum 14 may be formed separately as shown in the drawing. In this case, the main body portion of the middle drum 14 to which the magnetic head 15 is attached is mounted on the lower drum 12 via the direct bearing 31 after the flange portion 14a is mounted on the lower drum 12.
a. Therefore, before assembling the main body portion of the middle drum 14, the lower drum 1
2 will be adjusted.

FIG. 4 shows a fourth embodiment of the rotary magnetic recording apparatus according to the present invention. In FIG. 4, the rotary magnetic recording device 40 has substantially the same configuration as the rotary magnetic recording device 10 shown in FIG. 1, but instead of the motor 18 provided near the lower end of the support shaft 13, The configuration is different only in that a flat rotary transformer 42 is provided instead of the motor 41 provided near the upper end and the rotary transformer 19. The motor 41 includes a stator 41 a having a coil fixedly arranged on a lower surface of the upper drum 12, and a rotor having a rotor magnet provided at an upper end of the middle drum 14 so as to face the stator 41 a in the axial direction. 41b. Further, the rotary transformer 42 is connected to the middle drum 14.
, And a stator 42b fixedly arranged on the upper surface of the lower drum 12.

According to this configuration, the rotary transformer 42
Is formed in a flat shape, a low-cost rotary transformer is used, and the cost of parts is reduced.

In the embodiment described above, the rotary magnetic recording apparatus 10 provided with two magnetic heads has been described. However, the present invention is not limited to this, and may be applied to a rotary magnetic recording apparatus provided with at least one magnetic head. It is clear that the present invention can be applied. Further, in the rotary magnetic recording device 30 shown in FIG. 3, the middle drum 14 has a flange portion 14a formed separately, but the flange 14a is formed separately in another embodiment, that is, in the other embodiment, 1 and 2
And the rotary magnetic recording apparatuses 10, 20, and 40 shown in FIG.

[0029]

As described above, according to the present invention, it is possible to provide a rotary magnetic recording apparatus which can be assembled easily with high accuracy at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a first embodiment of a rotary magnetic recording apparatus according to the present invention.

FIG. 2 is a schematic sectional view showing a second embodiment of the rotary magnetic recording device according to the present invention.

FIG. 3 is a schematic sectional view showing a third embodiment of the rotary magnetic recording apparatus according to the present invention.

FIG. 4 is a schematic sectional view showing a fourth embodiment of the rotary magnetic recording apparatus according to the present invention.

FIG. 5 is a schematic sectional view showing an example of a conventional rotary magnetic recording device.

[Explanation of symbols]

10, 20, 30, 40 ... rotating magnetic recording device, 11
... upper drum, 12 ... lower drum, 13 ... support shaft, 14 ... middle drum (rotary drum), 14a ...
Flange part, 15 ... magnetic head, 16 ... bearing,
17 ... preload ring, 18 ... motor, 19 ...
Rotary transformer, 31 ... direct bearing,
41 ... motor, 42 ... flat rotary transformer.

Claims (10)

[Claims] 1. An upper drum and a lower drum, a middle drum rotatably supported between the upper drum and the lower drum, and a peripheral edge of the middle drum from a gap between the upper drum and the lower drum. At least one magnetic head attached so as to protrude outward, and a middle drum driven to rotate around a support shaft, wherein the support shaft for rotatably supporting the middle drum is an upper drum and A rotating magnetic recording device fixedly held to a lower drum, wherein the middle drum is rotatably supported on the support shaft via a bearing. 2. The support shaft is press-fitted at least at one end to an upper drum or a lower drum,
2. The rotating magnetic recording apparatus according to claim 1, wherein the rotating magnetic recording apparatus is fixed. 3. The rotary magnetic recording apparatus according to claim 1, wherein the support shaft is fixed at least at one end to an upper drum or a lower drum by shrink fitting. 4. The rotating magnetic recording apparatus according to claim 1, wherein the support shaft is fixed at least at one end to an upper drum or a lower drum by screwing. 5. The rotating magnetic recording apparatus according to claim 1, wherein the support shaft has a preload applied to a bearing at one end by a preload ring. 6. The rotary magnetic recording apparatus according to claim 1, wherein the support shaft directly applies a preload to the bearing at one end by an upper drum or a lower drum. 7. The rotating magnetic recording apparatus according to claim 1, wherein the bearing that rotatably supports the middle drum is a direct bearing. 8. A bearing and a magnetic head are provided on the middle drum,
2. The rotary magnetic recording apparatus according to claim 1, wherein a rotary transformer for inputting / outputting a signal of a magnetic head and a rotating unit are integrated. 9. A magnetic drum and a rotary transformer for signal input / output of the magnetic head are integrated with the middle drum, and a flange provided with a bearing is integrated with the middle drum. The rotating magnetic recording apparatus according to claim 1, wherein: 10. The rotating magnetic recording apparatus according to claim 1, wherein said rotating means is disposed above a middle drum.