JPH0452828Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to a grounding mechanism for a rotating magnetic head drum used in a VTR or the like.

<Summary of the invention> The invention provides a grounding mechanism for a rotating magnetic head drum by providing a protrusion between the bearings of the lower drum, a conductive grease for conducting electricity between the protrusion of the lower drum and the shaft, and the conductive grease. By providing a gasket to prevent leakage, it is possible to ground inside the lower drum, and the purpose is to simplify the grounding mechanism.

<Prior Art> FIG. 2 shows a conventional grounding mechanism for a rotating magnetic head drum.

In this description, explanation of the structure of the rotating magnetic head drum itself will be omitted.

The grounding mechanism of a rotating magnetic head drum consisting of an upper drum 1, a lower drum 2, and a shaft 6 that supports them has a grounding brush assembly b fixed to a mounting base 7 with mounting screws 8, and a grounding brush contact a connected to the rotating shaft 6. The structure was such that the upper end surface of the drum was pressed by a spring 10, and the upper drum side was grounded to a mechanical chassis (not shown) via a mounting base. In addition, the earth brush assembly b includes a mounting screw 8, an angle 9, and a spring 1.
It consists of 0.

<Problems to be solved by the invention> In the conventional grounding structure of a rotating magnetic head drum, the grounding brush was attached to a mounting base for fixing the drum in the tape running position, which made the grounding brush design complicated. Accuracy of installation work was required. In addition, if the ground brush contact is not brought into contact with the center of the rotating shaft, abnormal noise will occur due to an increase in the sliding area, and if external force is applied to the ground brush during assembly or adjustment, the ground brush will deform and the ground will be disconnected. I had a problem with it coming off.

<Function> According to the present invention, a protrusion is provided on the lower drum side,
By interposing conductive grease between the rotary shaft and the rotating shaft, grounding can be performed on the lower drum side. Therefore, the parts of the earth brush assembly are unnecessary.
The number of parts is reduced, resulting in cost reduction. Also,
The generation of abnormal noise, which was a problem in the past, is eliminated, and poor contact due to deformation of the grounding brush is also eliminated, making the reliability of the grounding on the upper drum side higher.

<Example> FIG. 1 shows the grounding structure of a rotating magnetic head drum according to the present invention.

A protrusion 2a is provided on the lower drum 2 between a pair of bearings 4 that fit into a rotary shaft 6, and a gap is provided between the protrusion 2a and the rotary shaft 6. Conductive grease 5 is applied to the gap, and gaskets 3 for preventing leakage of the conductive grease 5 are arranged at both ends of the projection 2a.

With the above configuration, the ground on the upper drum side is grounded to the mechanical chassis via the lower drum 2 using the conductive grease 5.

<Effects of the invention> As described above, according to the invention, parts of the earth brush assembly are unnecessary, the number of parts is reduced, and costs are reduced. Furthermore, the occurrence of abnormal noise, which was a problem in the past, is eliminated, and contact failure due to deformation of the grounding brush is also eliminated, making the reliability of the grounding on the upper drum side higher.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a grounding mechanism for a rotating magnetic head drum according to the present invention, and FIG. 2 is a sectional view of a conventional grounding mechanism for a rotating magnetic head drum. 1...Upper drum, 2...Lower drum, 2a...Protrusion, 3...Putskin, 4...Bearing, 5...
...Conductive grease, 6...Rotating shaft, 7...
Mounting base.

Claims (1)

[Scope of utility model registration request] In a magnetic recording and reproducing device, the magnetic recording and reproducing device has a lower drum that allows the magnetic tape to run at a fixed position on the outer circumferential surface by a guide portion, and an upper drum that has a built-in magnetic head and is rotationally driven by a drive source via a shaft. A protrusion is provided between a pair of bearings that fit with the shaft on the lower drum side, and a packing is provided between the shaft and the protrusion to prevent leakage of the conductive grease, with conductive grease interposed between the shaft and the protrusion. A grounding mechanism for a rotating magnetic head drum, characterized in that the upper drum side is grounded by.