JPH06188052A - Slip ring for vtr rotation drum - Google Patents

Abstract

PURPOSE:To exclude debris, adhering to the surface of a slip ring, in slits to stabilize contact resistance, by providing slits, in parallel to an axis, on a cylinder surface slidingly contacting the feeding brush of the slip ring. CONSTITUTION:Slip ring pieces 83, composed of noble metal alloy, are arranged at regular intervals on the outer peripheral surface of a core body 81, and a fixing washer 82 is pressed in to form a slip ring 8 having slits 84. The slip ring 8 is made an insulated condition in an axis direction to be pressed-in fixed to a rotation shaft 7. By this constitution, even if the debris such as dust adhere on the surface of the slip ring 8, the debris is excluded in the slits 84 by a feeding brush 9, slidingly contacted to the surface, to be lockedly accumulated for keeping the surface of the slip ring 8 clean always. Consequently, contact resistant with the feeding brush is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power feeding device used for feeding power from outside to an electronic component, for example, a preamplifier incorporated in a rotary drum which constitutes a video tape recorder (hereinafter referred to as VTR). The present invention relates to a slip ring, and more particularly to a slip ring for a VTR rotary drum which is improved so as not to generate noise and to maintain a stable contact state with a power feeding brush.

[0002]

2. Description of the Related Art FIG. 2 is a front view of the essential parts showing the vicinity of a VTR rotary drum provided with a slip ring which is the object of the present invention. In FIG. 2, reference numeral 1 is a fixed drum, which is formed in a short cylindrical shape and fixed to the chassis 2. Reference numeral 3 denotes a rotary drum, which is formed in a short columnar shape similar to that of the fixed drum 1, is provided with, for example, two magnetic heads 4 in the vicinity of the outer periphery, is provided coaxially with the fixed drum 1, and can be rotated by a drive motor 5. Has been formed.

Next, 6 is a power feeding device, which is coaxially provided on the upper end surface of the rotary drum 3 and is in sliding contact with the rotary shaft 7, the slip ring 8 fixed to the rotary shaft 7, and the cylindrical outer peripheral surface of the slip ring 8. The power supply brush 9 and the cover 10 that are provided as described above are included. Reference numeral 11 denotes a bracket, which is provided on the chassis 2 and supports the power feeding device 6.

With the above structure, the rotary drum 3 is rotated by the drive motor 5 at, for example, 1800 rpm, and a magnetic tape (not shown) is run horizontally on the cylindrical surface of the rotary drum 3 so that the magnetic head 4 is passed through. It is possible to scan the magnetic tape diagonally and record and reproduce image information. In this case, a rotary transformer (not shown) may be provided on the opposing surfaces of the rotary drum 3 and the fixed drum 1 to exchange signals with the magnetic head. In recent years, by incorporating a preamplifier in the rotary drum 3, it is possible to send and receive a signal having a good S / N ratio and to reduce the number of phases of the rotary transformer. The power supply device 6 shown in FIG. 2 is a device for supplying power to the preamplifier from an external power supply.

[0005]

The above-mentioned conventional power feeding device 6
The slip ring 8 constituting the slip ring 8 is formed in a hollow cylindrical shape from a noble metal alloy such as a gold alloy or a platinum group alloy, and is fixed to the rotating shaft 7 via an insulating material. The power supply brush 9 is slidably contacted with the outer peripheral cylindrical surface. In such a configuration, when dust or other foreign matter adheres to the outer peripheral cylindrical surface of the slip ring 8, the slip ring 8 is locked with the power feeding brush 9, and therefore the electrical contact between the power feeding brush 9 and the slip ring 8 is made. The conduction becomes unstable or cut off.

As a result of the above, an undesired situation such as power supply failure or noise generation is brought about, and a malfunction occurs in the preamplifier or IC unit incorporated in the rotary drum 3, and the quality of image information recorded or reproduced. There is a problem in that

Further, since the entire slip ring 8 is formed of an expensive noble metal alloy, there is a problem that the manufacturing cost is increased. On the other hand, if the thickness dimension of the slip ring 8 is reduced in order to reduce the amount of the precious metal alloy used, the mechanical strength and life of the slip ring 8 are reduced, and therefore there is a limit to the reduction of the thickness dimension. However, there is a problem that it is difficult to significantly reduce the manufacturing cost.

The present invention solves the problems existing in the above-mentioned prior art, the contact state with the power feeding brush is stable, no noise is generated, and the manufacturing cost can be reduced.
An object is to provide a slip ring for a TR rotating drum.

[0009]

In order to achieve the above object, according to the present invention, a magnetic head is provided in the vicinity of the outer periphery and is coaxial with an end surface portion of a rotary drum which is rotatably formed coaxially with a fixed drum. In the slip ring for a VTR rotary drum, which is provided in the above and is configured to supply power to electronic components built in the rotary drum, a technical means is adopted in which a slit parallel to the axis is provided on a cylindrical surface that is in sliding contact with the power supply brush. did.

[0010]

With the above structure, even if an insulating foreign substance adheres to the surface of the slip ring, the foreign substance is removed into the slit by sliding with the power feeding brush, so the surface of the slip ring is kept clean. Therefore, the contact resistance with the power feeding brush can be stabilized.

[0011]

1 is an enlarged perspective view of an essential part showing an embodiment of the present invention, in which the same parts are designated by the same reference numerals as in FIG.
In FIG. 1, reference numeral 81 denotes a core, which is made of an insulating material such as nylon 6 into a hollow cylindrical shape, and the inner diameter of the hollow portion is substantially the same as the outer diameter of the rotary shaft 7 shown in FIG. The core body 81 can be press-fitted and fixed to the rotary shaft 7. Reference numeral 82 denotes a fixing washer, which is made of an insulating material similar to that of the core body 81 and is formed in a hollow disk shape.

Next, 83 is a slip ring piece, which is made of a noble metal alloy and has an arc-shaped cross section, for example, the center angle of each arc of the cross section is less than 120 °. Such a slip ring piece 83 is preferably formed by, for example, press molding punching means. When the slip ring pieces 83 are arranged on the outer peripheral surface of the core body 81 at equal intervals in the circumferential direction, and the fixing washers 82 are press-fitted into the end surface portions, the slits 84 extending parallel to the axial direction are formed. As a result, the slip ring 8 having a cylindrical outer peripheral surface is formed. The slip rings 8 thus formed are axially insulated as shown in FIG. 2 and are press-fitted and fixed to the rotary shaft 7.

With the above structure, as shown in FIG. 2, the power feeding brush 9 is slidably contacted with the outer peripheral cylindrical surface of the slip ring 8 to form the power feeding device 6, and an external power source via the power feeding brush 9 and the slip ring 8. It is possible to supply power to the electronic components built in the rotary drum 3. In this case, as shown in FIG. 1, since the slit 84 is provided on the outer peripheral cylindrical surface of the slip ring 8 in parallel with the axis, dust or other insulating foreign matter is attached to the surface of the slip ring 8. Also, the slit 8 is formed by a power supply brush (not shown, see reference numeral 9 in FIG. 2) that is in sliding contact with this surface.
The surface of the slip ring 8 is always kept clean because it is excluded and locked and accumulated in 4. Therefore, the contact resistance with the power feeding brush can be stabilized.

In this embodiment, the slip ring piece 8 is used.
Although the example in which 3 is integrally formed of a noble metal alloy is described, means for fixing a foil of a noble metal alloy on the surface of the body of, for example, a copper alloy, or forming a thin film on the surface of the body by vapor deposition, electrodeposition, or the like. In other words, it suffices that the noble metal alloy is applied to the minimum necessary area that is in sliding contact with the power supply brush. Therefore, for example, a noble metal alloy foil may be placed on the surface of a low-priced copper strip, and a clad-processed composite material may be formed and then pressed.

[0015]

EFFECTS OF THE INVENTION Since the present invention has the structure and operation as described above, the following effects can be obtained. (1) By providing a slit parallel to the axis on the cylindrical surface on the outer periphery of the slip ring, foreign matter adhering to the cylindrical surface can be easily removed by a power supply brush that is in sliding contact, and the foreign matter can be accumulated and retained in the slit. Therefore, the contact resistance between the power feeding brush and the slip ring can be stabilized, and the generation of noise can be prevented. (2) Since the slip ring can be constructed by assembling a plurality of slip ring pieces, the use of an expensive precious metal alloy can be suppressed to a necessary minimum and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an enlarged perspective view of essential parts showing an embodiment of the present invention.

FIG. 2 V with a slip ring which is the subject of the present invention
It is a principal part front view which shows the TR rotating drum vicinity.

[Explanation of symbols]

 3 Rotating drum 8 Slip ring 84 Slit

[Procedure amendment]

[Submission date] September 3, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

Claims (2)

[Claims] 1. A rotary drum (3) having a magnetic head (4) in the vicinity of the outer periphery thereof and coaxially provided on an end face portion of a rotary drum (3) formed so as to be rotatable coaxially with the fixed drum (1). ) In a slip ring for a VTR rotary drum configured to feed power to an electronic component built in, a slit (84) parallel to the axis is provided on a cylindrical surface that is in sliding contact with the power feeding brush (9). Slip ring for VTR rotating drum. 2. A slip ring (8) by sandwiching a plurality of slip ring pieces (83) having an arc cross section with a hollow cylindrical core body (81) and a hollow disk-shaped fixing washer (82). ) Is constituted, the slip ring for the VTR rotary drum.