JPH0528444A - Drum structure - Google Patents

Abstract

PURPOSE:To provide the drum structure which allows the easy adjustment of the positions of upper and lower drums and allows easy working. CONSTITUTION:A supporting member 3 which supports and fixes the upper drum 1 and the lower drum 2 is axially bisected. The divided upper supporting member 3a and lower supporting member 3b are respectively fixed to the upper drum 1 and the lower drum 2 and the upper and lower supporting members 3a, 3b are fastened by means of bolts 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum structure which is provided in a magnetic recording / reproducing apparatus such as a video tape recorder and which guides traveling by attaching a magnetic tape, and more particularly to a drum structure comprising fixed upper and lower drums.

[0002]

2. Description of the Related Art A conventional drum structure of this type is shown in FIG.
Through, it was configured as shown in FIG. That is, the fixed upper drum 1 and the fixed lower drum 2 which are concentrically arranged are attached to the support members 3 provided on the outer circumferences of these drums 1 and 2,
Each is fixed via a pair of screws 4 and 5. Then, a spacer 6 is inserted between the outer periphery of the lower drum 2 and the support member 3 so that the upper and lower drums 1 and 2 are positioned concentrically. A flange 8 is rotatably supported at the center of the lower drum 2 via a rotary shaft 7 as shown in FIG. 6, and a plurality of magnetic heads 9 are attached to the outer periphery of the flange 8. The magnetic head 9 rotates at high speed along the gap between the upper and lower drums 1, 2.

As another example of the conventional drum structure,
In some cases, the upper and lower drums 1 and 2 and the supporting member 3 are integrally molded as shown in FIG.

[0004]

However, according to the conventional drum structure shown in FIGS. 4 to 6, the upper and lower drums 1,
Since the spacer 6 is used for position adjustment 2 and the spacers having various thicknesses are exchanged for adjustment, there is a problem that the work becomes complicated.

Further, according to the conventional drum structure shown in FIG. 7, there is a defect that the shape is complicated and the processing is difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drum structure in which the positions of the upper and lower drums can be easily adjusted and the processing is easy.

[0007]

SUMMARY OF THE INVENTION The drum structure of the present invention comprises:
In a drum structure having a fixed upper drum and a fixed upper and lower drum arranged concentrically, a rotary magnetic head rotating along a gap between both drums, and a support member for supporting and fixing both drums, the support member is a drum. Divided into two in the axial direction of
The divided upper and lower support members are fixed to the upper and lower drums, respectively, and the upper and lower support members are fixed via fastening means.

[0008]

In the drum structure having the above construction, the conventional supporting member is simply divided into two in the axial direction, so that the processing is easy. Further, by loosening the fastening means for fastening the pair of upper and lower support members and relatively moving the upper and lower support members in the radial direction of the drum, the upper and lower drums can be easily aligned with each other.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the drum structure of the present invention will be described below with reference to the drawings.

1 and 2 show the configuration of an embodiment of the present invention. In these figures, parts corresponding to the parts of the conventional example shown in FIGS. 4 to 6 are designated by the same reference numerals, and description thereof will be omitted as appropriate. In FIG. 2, the fixed lower drum 2
A rotary shaft 7 is rotatably supported at the center of the shaft via a pair of bearings 10 and 11 in the axial direction. A flange 8 is concentrically fixed to the upper end of the rotating shaft 7, and a rotary transformer 12 on the rotating side is provided on the inner circumference of a cylindrical portion formed in the lower portion of the flange 8. Fixed F drum 2
A fixed-side rotary transformer 13 is provided facing the rotary-side rotary transformer 12 on the outer circumference of the cylindrical portion that surrounds the outer circumference of the rotating shaft 7 at the center. Further, a magnetic head 9 is attached to the outer circumference of the flange 8. Also the rotating shaft 7
Is rotationally driven by a motor 14 provided below the fixed lower drum 2.

On the other hand, a fixed upper drum 1 is disposed substantially concentrically above the fixed lower drum 2, and the upper drum 1 and the lower drum 2 have a support member 3 as shown in FIGS. Is fixed through. The support member 3 is divided into two parts in the axial direction to form an upper support member 3a and a lower support member 3b.

Next, a procedure for fixing the upper drum 1 and the lower drum 2 with the support member 3 will be described. First, the support member 3b is fastened to the lower drum 2 with a pair of screws 5. At this time, the lower surface of the lower drum 2 and the lower surface of the lower support member 3b are attached so as to be flush with each other. Next, the upper support member 3a is attached to the upper drum 1.
Are fastened with a pair of screws 4. At this time, the positioning plate 15 mounted on the outer periphery of the upper surface of the upper drum 1 is used as a reference so that the upper surface of the upper drum 1 and the upper surface of the upper support member 3a are flush with each other. Next, the lower surface of the upper supporting member 3a and the upper surface of the supporting member 3b are butted against each other and lightly fastened together by a pair of bolts 16. Then, after moving the upper drum 1 with respect to the lower drum 2 to adjust the outer peripheral surfaces to match,
The bolt 16 is fastened with sufficient torque to withstand an external force.

According to this embodiment, a spacer is not required for adjusting the concentricity of the upper and lower drums 1 and 2 as in the conventional case, and the adjustment can be easily performed in a short time. Further, by loosening the screw 16 again after fastening, the upper drum 1 and the lower drum 2 can be relatively moved, so that readjustment and the like can be easily performed.

The upper and lower drums 1 and 2 and the supporting members 3a,
By tightening the roughness of the contact surface with 3b by cutting or lapping, the fastening of both can be ensured.

As shown in FIG. 3, the upper drum 1 and the upper support member 3a, and the lower drum 2 and the lower support member 3b are integrally formed into members 17 and 18, respectively, and the members 17 and 18 are paired with a pair of screws. You may fasten with 16.

[0016]

As described above, according to the drum structure of the present invention, the upper and lower supporting members are fastened to the upper and lower drums, respectively, and the upper and lower supporting members are fastened by the fastening means. The position of the drum can be easily adjusted.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a configuration of an embodiment of a drum structure of the present invention.

FIG. 2 is a vertical sectional view showing a rotating mechanism of the drum shown in FIG.

FIG. 3 is a perspective view showing the configuration of another embodiment of the drum structure of the present invention.

FIG. 4 is an exploded view showing the configuration of an example of a conventional drum structure.

5 is a plan view of FIG.

6 is a vertical cross-sectional view of FIG.

FIG. 7 is a perspective view showing the configuration of another example of a conventional drum structure.

[Explanation of symbols]

 1 fixed upper drum 2 fixed lower drum 3 support member 3a upper support member 3b lower support member 9 magnetic head 16 bolt (fastening means)

Claims (1)

Claim: What is claimed is: 1. A fixed upper drum and a fixed lower drum which are concentrically arranged, a rotary magnetic head which rotates along a gap between the both drums, and both the drums are supported and fixed. In a drum structure having a supporting member, the supporting member is divided into two in the axial direction of the drum, and the divided upper supporting member and lower supporting member are fixed to the upper drum and the lower drum, respectively, and the upper supporting member is provided. And a lower support member fixed via fastening means.