JPH0220791Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention is used when transmitting and receiving electrical signals between a rotating body with a finite number of rotations and a fixed body, such as an automobile steering system. The present invention relates to a brushless electrical signal transmission device.

(Prior art) This type of brushless electric signal transmission device includes one in which an upper connector and a lower connector are connected by a spiral cord as described in Japanese Patent Publication No. 1274/1983, and the one shown in Fig. 1. A brushless electrical signal device as shown has been proposed. The present invention relates to an improvement of a brushless electric signal transmission device as shown in FIG. This brushless electric signal transmission device has a first housing 1 and a second housing 2, each having a substantially cylindrical shape, which are concentrically and relatively rotatably combined, and a fixing ring 4 is connected via a lubricating washer 3. The second housing 2 is fitted into the second housing 2 for connection, and a substantially strip-shaped spiral conductor 6 having a plurality of electrically conductive paths is spirally housed in a ring-shaped chamber 5 in both housings 1 and 2. ,
One end thereof is led out to the outside from an opening 7 provided in the first housing 1, and the other end is led out to the outside from an opening 8 provided in the second housing 2.
One housing was supported by a rotating body, and the other housing was supported by a fixed body.

In this case, the spiral conductor 6 is wound or unwound by the rotation of either the housing 1 or 2, but in the case of a conventional brushless electric signal transmission device, the spiral conductor 6 is
The spiral end face in the width direction of the first housing 1
inner surface 1A of the second housing 2 and inner surface 2A of the second housing 2.
Fricative noise is produced by rubbing. Further, vibration having a directional component along a plane perpendicular to the common central axis of the first and second housings 1 and 2;
Even when an impact is applied, the spiral conductor 6 swings within the chamber 5, causing the inner surfaces 1A and 2A to
Fricative noise is produced due to friction. When this brushless electric signal transmission device is applied to, for example, a steering device of an automobile, the generation of these frictional noises has the disadvantage of having a negative psychological effect on the driver.

(Purpose of the invention) An object of the invention is to provide a brushless electric signal transmission device that can reduce frictional noise.

(Structure of the invention) The present invention is characterized in that a first housing and a second housing are combined concentrically and relatively rotatably, and a ring-shaped chamber formed by the two housings has an electrically conductive path. In the brushless electric signal transmission device, a strip-shaped spiral conductor is housed in a spiral shape, one end of which is supported by the first housing, and the other end of which is supported by the second housing, in which the spiral conductor in the chamber is It is characterized in that rib-like protrusions are provided radially on each inner surface of the body facing the spiral surface.

When the rib-like protrusions are provided in a radial manner in this way, the frictional area is significantly reduced, and the generation of frictional noise can be reduced.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to FIGS. 2 and 3. Note that parts corresponding to those in FIG. 1 are designated by the same reference numerals. In the brushless electric signal transmission device of this embodiment, rib-like protrusions 9 and 10 are provided radially protruding from the inner surfaces 1A and 2A of both housings 1 and 2, where the spiral surfaces of the spiral conductor 6 face each other in the chamber 5. There is.

FIG. 4 shows another embodiment of the present invention. In the brushless electrical signal transmission device of this embodiment, the rib-like protrusions 9 and 10 (9 is not shown in this figure) are spirally curved along the locus drawn by the spiral conductor 6 by winding or unwinding. This is an example.

In this way, frictional noise can be further reduced compared to the above-described embodiment.

(Effect of the invention) As explained above, in the brushless electric signal transmission device according to the invention, rib-like protrusions are provided radially on both inner surfaces of the spiral conductor in which the spiral surfaces of the spiral conductor face each other in the chamber housing the spiral conductor. Therefore, the frictional area is significantly reduced, and the generation of frictional noise can be reduced. Moreover, in this case, the frictional resistance applied during the operation of the spiral conductor is reduced, and the spiral conductor can be moved more smoothly than before.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a conventional device, Fig. 2 is a longitudinal sectional view showing an embodiment of the device according to the present invention, and Fig. 3 is a longitudinal sectional view of a second housing used in the embodiment of Fig. 2. FIG. 4 is a perspective view showing another example of rib-like projections provided on the housing. 1...First housing, 1A...Inner surface, 2
...Second housing, 2A...Inner surface, 5...
Chamber, 6... spiral conductor, 9, 10... rib-like projection.

Claims (1)

[Scope of utility model registration request] A first housing and a second housing are concentrically and relatively rotatably combined, and a substantially strip-shaped spiral conductor having an electrically conductive path is spirally arranged in a ring-shaped chamber formed by the two housings. In a brushless electrical signal transmission device housed in the device, one end of which is supported by the first housing and the other end of which is supported by the second housing, an inner surface of the spiral conductor in the chamber where the spiral surfaces of the spiral conductor face each other; A brushless electric signal transmission device characterized in that rib-like protrusions are provided in a radial manner on each side.