JP3159333B2 - Rotary drum device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary drum device,
In particular, the present invention can be applied to a rotating drum device having a so-called upper drum fixing structure in which an upper drum is fixed to a lower drum.

[0002]

2. Description of the Related Art Conventionally, this kind of rotary drum device 1 has
As shown in FIG. 10, a cylindrical upper drum 2 and a lower drum 3 having the same outer diameter are integrally held by using a plate-shaped drum support member 4, and the upper drum 2 and the lower drum 3 There is one in which a head scanana 5 is disposed inside.
The head scanner 5 includes a middle drum (not shown) on which a magnetic head is mounted, and is fixed to a rotating shaft (not shown) of the motor 6 by conducting a drive current to a built-in motor 6. The middle drum rotates.

Accordingly, in the rotating drum device 1, a magnetic tape (not shown) running obliquely and wound around the peripheral side surfaces of the upper and lower drums 2 and 3 is used to form a gap G between the upper and lower drums 2 and 3. A helical scan is performed by the rotating magnetic head, so that a desired video signal or audio signal is recorded or reproduced. In this case, the drum supporting member 4 has an arc surface having substantially the same curvature as the outer diameter of the upper and lower drums 2 and 3 (hereinafter referred to as the drum outer diameter). The bolts 7 are used to fasten the upper and lower drums 2 and 3 integrally with the drums 2 and 3 in contact with the drums 2 and 3.

Further, a height regulating plate 8 is attached to the upper drum 2 by screws 9 so as to protrude outward from the upper end surface of the upper drum 2, whereby a fastening position of the drum supporting member 4 in the height direction is provided. At the position where the upper end surface of the drum supporting member 4 is in contact with the lower surface of the height regulating plate 8.

[0005]

By the way, in the case of this kind of rotary drum device 1, the upper and lower drums 2 are assembled at the time of assembly.
The upper and lower drums 2 and 3 are assembled while adjusting their relative positions in the circumferential direction in consideration of the contact of the magnetic tape with the upper and lower drums 2 and 3 in units of micrometers. However, in the rotary drum device 1, the fastening portion between the upper and / or lower drums 2 and / or 3 and the drum support member 4 may move during an impact test after assembly, and as a result, the circle with respect to the upper and lower drums 2 and 3 may be moved. The relative position in the circumferential direction changed.

For this reason, in the rotary drum device 1, as a method for preventing the change of the relative position, as shown in FIG. 11, the width of the contact surface of the drum support member 4 with the upper and lower drums 2 and 3 (hereinafter referred to as "the width"). This is called a drum support mounting width). However, according to this method, the drum support member 4 becomes large as the drum support mounting width is increased, so that a large occupied space is required as a whole of the rotary drum device 1 and the curvature of the contact surface of the drum support member 4 is increased. Must be accurately adjusted in a wide range, which complicates the production work, and as a result, there is a practical problem such as an increase in the production cost.

Further, in the case of the rotary drum device 1, the curvature of the contact surface of the drum support member 4 with the upper and lower drums 2 and 3 does not match the diameter of the drum.
And 3, the upper and lower drums 2 and 3 may be deformed. However, in the drum support member 4, since the range of the curvature of the contact surface is only 20 ° depending on the model, it is difficult to control the curvature dimension of the upper and lower drums 2 and 3 together. There was a problem.

The present invention has been made in view of the above points, and an object of the present invention is to propose a rotary drum device which can improve impact resistance without requiring a large occupied space and can be manufactured at low cost. .

[0009]

According to the present invention, in order to solve the above-mentioned problem, the upper drum 2 fastens the lower drum 3 by means of drum supporting means, so that the gap G between the upper and lower drums 2 and 3 is reduced. In a rotary drum device 20 for helically scanning a magnetic tape wound around an outer peripheral surface by a rotating magnetic head, a drum supporting means is constituted by a plurality of columnar drum supporting members 21A and 21B. In the present invention, the contact surfaces 2A, 2B and 3 of the upper and lower drums 2 and 3 with the drum supporting members 21A and 21B are provided.
A, 3B and the contact surfaces SA and SB of the drum support members 21A and 21B between the upper and lower drums 2 and 3 were formed flat.

[0010]

The drum supporting means is constituted by a plurality of columnar drum supporting members 21A and 21B.
A rotating drum device capable of providing a large drum support mounting width in a small occupying space, thus reducing the occupying space of the rotating drum device 20 as a whole and improving reliability with respect to impact resistance. it can.

In the present invention, the upper and lower drums 2
And 3B, the contact surfaces 2A, 2B and 3A, 3B with the drum support members 21A and 21B, and the drum support member 21
By forming the contact surfaces SA and SB of the A and 21B with the upper and lower drums 2 and 3 as flat surfaces, the dimensional control of the drum support members 21A and 21B at the time of processing is facilitated, thus assembling and adjusting work. The rotary drum device 20 which can be manufactured easily and can reduce the manufacturing cost can be realized.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

In FIG. 1, in which parts corresponding to those in FIGS. 10 and 11 are assigned the same reference numerals, the upper drum 2 and the lower drum 3 of the rotary drum device 20 are connected to two rectangular parallelepiped drum supporting members 21A and 21B. And are fastened together.
In this case, the upper and lower drums 2 and 3 of the rotary drum device 20
Are, as shown in FIG. 2, drum support members 21A and 21A.
The contact surfaces 2A, 2B and 3A, 3B (hatched portions) with B are flattened, and the contact surfaces SA and SB of the drum support members 21A and 21B with the upper and lower drums 2 and 3.
(FIG. 4) is processed into a plane, and the bolt 7 is connected to the upper and lower drums 2 and 3 via the drum supporting members 21A and 21B.
, The upper and lower drums 2 and 3 and the drum support members 21A and 21B are fastened.

In the above configuration, the rotary drum device 20
Is assembled in substantially the same procedure as that of the conventional rotary drum device 1 as shown in FIG. That is, the rotating drum device 2
0, the step S of the assembly and adjustment work RT0
After attaching the height regulating plates 8A and 8B to the upper drum 2 with screws 9A and 9B in P1 (FIG. 2), the upper ends of the drum supporting members 21A and 21B are attached to the height regulating plates 8A and 8B in step SP2. By screwing the screws 7A and 7B into the screw holes 11A and 11B formed in the contact surfaces 2A and 2B in the contact state, the upper drum 2
The upper portions of the drum supporting members 21A and 21B are fastened (FIG. 4), and the screws 7A and 7B are similarly screwed into the screw holes 11A and 11B formed in the contact surfaces 3A and 3B at step SP3. The lower portions of the drum support members 21A and 21B are fastened to the drum 3 (FIG. 5).

Then, in step SP4, as shown in FIGS. 6 and 7, the upper and lower drums 2 and 3 integrated by the drum supporting members 21A and 21B are placed on a predetermined jig plate 22. The micrometer 23 is used to measure whether or not the difference between the relative positions of the upper and lower drums 2 and 3 in the circumferential direction is within a predetermined allowable range. If a positive result is obtained, the assembly and adjustment are performed in step SP6. Finish the work. On the other hand, if a negative result is obtained in step SP4, the process proceeds to step SP5, where the bolts 7A and / or 7B for fastening the lower drum 3 to the drum supporting members 21A and / or 21B are removed and the lower drum 3 is removed. After a spacer 24 having a predetermined thickness is interposed between the drum and the drum supporting members 21A and / or 21B (FIG. 5), the process returns to step SP3, and then returns to step SP4 until a positive result is obtained in step SP4. -SP6-
The adjustment work is repeated by the loop of SP3.

According to the above construction, the contact surfaces 2A, 2B formed of flat surfaces formed on the outer surfaces of the upper and lower drums 2, 3
The two drum support members 21A and 21B are in a state where the flat contact surfaces SA and SB are in contact with the drum support members 21A and 21B.
Are fastened to the upper and lower drums 2 and 3, so that the upper and lower drums 2 and 3 can increase the mounting width between the two rectangular parallelepiped drum support members 21A and 21B as necessary. Thus, the rotary drum device 20 having high impact resistance can be realized. Further, the working of the contact surfaces SA and SB of the drum support members 21A and 21B with the upper and lower drums 2 and 3 is facilitated, and the dimensional management of the contact surfaces SA and SB is further facilitated. The costs of the support members 21A and 21B and the rotating drum device 20 can be reduced.

The upper and lower drums 2 and 3 are held in a predetermined state by two rectangular parallelepiped drum supporting members 21A and 21B, so that the upper and lower drums 2 and 3 rotate as shown in FIG. The drum supporting members 21A and 21B can be attached to the dead space of the drum device 20, respectively, and thus the occupied space of the rotary drum device 20 can be reduced. Further, the drum support members 21A and 21A
By making the contact surfaces SA and SB with the upper and lower drums 2 and 3 flat in B, the quality of the drum support members 21A and 21B in a single item state can be easily controlled, and thus, at the time of receiving inspection. In this case, it is possible to effectively prevent the occurrence of a defect in the rotary drum device 20, for example, by making it easier to detect a defective product in the above.

In the above-described embodiment, the drum supporting members 21A and 21B are fastened to the upper and lower drums 2 and 3, and the upper and lower drums 2 and 3 are held in a predetermined state by the drum supporting members 21A and 21B. Although the case where the upper drum 2 is formed is described above, the present invention is not limited to this, and as shown in FIG. 9, the upper drum 2 with the L-shaped drum supporting member 30 fastened to the fastener 31 side. In this case, the upper drum 2 and the lower drum 3
The fine adjustment of the relative position may be made electrically while running a magnetic tape (not shown). Further, in the above-described embodiment, the case where the upper and lower drums 2 and 3 are fastened using the two divided type drum support members 21A and 21B has been described, but the present invention is not limited to this. Three or more drum support members 21A and 21B may be used.

Further, in the above-described embodiment, the case where the drum supporting members 21A and 21B are formed in the shape of a rectangular parallelepiped has been described. However, the present invention is not limited to this. If the surfaces SA and SB are columnar formed or processed to be flat, the drum supporting members 21A and 21A
Various shapes can be applied as the shape of 1B.

[0020]

As described above, according to the present invention, the drum supporting means is constituted by a plurality of columnar drum supporting members, so that the drum supporting mounting width can be widened in a narrow occupied space. Thus, the occupied space of the entire rotary drum device can be reduced as compared with the conventional case, and the drum support mounting width can be made as wide as the magnetic tape path system allows, thus the impact resistance of the rotary drum device can be reduced. Performance can be improved.

Further, since the abutment surfaces of the upper and lower drums with the drum support member and the abutment surfaces of the drum support member with the upper and lower drums are formed as flat surfaces, dimensional control during processing or the like is facilitated. Thus, the production cost of the drum support and the rotary drum device can be reduced. Furthermore, since it is easy to manage by receiving inspection and the like, and occurrence of defects can be prevented beforehand, it is possible to realize a rotary drum device that can further improve reliability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a rotary drum device according to the present invention.

FIG. 2 is a perspective view showing contact surfaces of upper and lower drums with a drum support.

FIG. 3 is a flowchart showing a procedure for adjusting and assembling the rotary drum device shown in FIG. 1;

FIG. 4 is a perspective view showing an operation of assembling the rotary drum device shown in FIG. 1;

FIG. 5 is a perspective view showing an operation of assembling and adjusting the rotary drum device shown in FIG. 1;

FIG. 6 is a schematic perspective view showing a method of adjusting a relative position of an upper drum and a lower drum in the rotary drum device shown in FIG.

FIG. 7 is a schematic enlarged view showing a measurement unit using the micrometer shown in FIG. 6;

FIG. 8 is a schematic plan view showing a mounting state of a drum supporting member.

FIG. 9 is a schematic perspective view showing a modification of the embodiment.

FIG. 10 is a perspective view showing a conventional rotary drum device.

FIG. 11 is a schematic plan view showing a mounting state of a conventional drum supporting member.

[Explanation of symbols]

1, 20 ... rotary drum device, 2 ... upper drum, 2A,
2B, 3A, 3B, SA, SB ... Contact surface, 3 ... Lower drum, 4, 21A, 21B, 30 ... Drum support member,
6 ... motor, 7 ... bolt, G ... gap.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 5/52 G11B 15/61

Claims (2)

(57) [Claims] An upper drum fastens a lower drum by drum support means, and a helical scan of a magnetic tape wound around an outer peripheral surface by a magnetic head rotating in a gap between the upper and lower drums. In the drum device, the drum supporting means is constituted by a plurality of columnar drum supporting members. 2. The device according to claim 1, wherein the contact surfaces of the upper and lower drums with the drum support member and the contact surfaces of the drum support member with the upper and lower drums are flat. Item 2. The rotary drum device according to Item 1.