Plug provided with elastic tongues having an approximately semi-circular or semi-cylindrical profile suitable for making the electrical connection between the plug and a socket

Abstract

 The invention consists of the discovery that by replacing the flat tongues in a plug-socket assembly by approximately semi-cylindrical tongues, the electric current capacity of said plug-socket assembly can be approximately doubled.

Description

[0001] This invention relates to a plug provided with two or more elastic metal tonpues of approximately semi-circular or semi-cylindrical profile which can be inserted into the relative socket of complementary profile, in order to make the electrical connection between the plug and socket.

[0002] The object of the invention Is to form electrical contacts which are reliable even when subjected to vibration due tb their being installed for example on a motor vehicle provided with a radio receiver, record player etc.

[0003] A plug is known provided with elastic flat tonrues suitably fixed to the top end of the plug stem.

[0004] Specifically, the elastic tongues of this known plug are perfectly flat, so that when the two tongues are inserted into the socket, four contact edges are theoretically determined.

[0005] We have discovered that by replacing the flat tongues with others of approximately semi-cylindrical or semi-circular profile, the socket-tongue contact surface can be approximately doubled, as can the power transmitted.

[0006] The plug accordinc to the present invention is further illustrated by way of non-limiting example in the following figures, in which Figures 1 to 5 and Figures 11 to 12 pertain to the invention, whereas Figures 6 to 10 pertain to the known art.

[0007] Figures of the invention:

Figure 1 is a plan view of a flat rectangular strip profiled in order to form two tongues 3 and comprising a central fixing hole 2;

Figure 2 is a front view of the strip 1 when suitably bent and profiled in order to form two tongues 3;

Figure 3 is a side view of Figure 2, showing the semi-circular or semi-cylindrical profile of the tongues 3;

Figure 4 is a partly sectional view of the plug of Figure 3, on the stem 4 of which is fitted the strip 1 with the tongues 3 bent along said stem;

Figure 5 is a cross-section through Figure 4; the stem 4, the tongues 3 and the socket 5 are visible;

Figures 11 and 12 are a side view of the plug comprising the tongues 3, prior its insertion into the socket 5,

Figures of the known art:

Figure 6 is a plan view of a flat rectangular strip 4;

Figures 7 and 8 are a front and side view respectively of the strip 7;

Figures 9 and 10 are respectively a partly sectional vertical front view of the plug mounted in the socket 8, and a transverse view thereof; the reference numeral 7 indicates the tongues.

[0008] A phosphor bronze having a Brinell hardness of 185-200 is advantageously used as the plug constructional material; the strip thickness is about 0.3 mm.

[0009] Furthermore, it has been found that the vertex angle of the cone formed by the tongues when not inserted is conveniently about 30°.

Claims

1. A metal plug comprising a stem (4), a socket (5) and a rectangular strip (1) with two or more tongues (3) for increasing the surface areas of electrical contact between the plug and socket and for approximately doubling the transmitted power, in which the stem (4) is fixed at one of its ends to the centre of said strip and at its other end is in contact with the socket (5), characterised in that said electrical contact is made by way of approximately semi-cylindrical surfaces.

2. A plug as claimed in claim 1, characterised in that the tongues (3) are fixed in such a manner as to be rotatable about the upper end of the stem (4).

3. A plug as claimed in claim 1 or 2, characterised in that the plug tongues (3) are two or more in number.

4. A plug as claimed in claim 1 comprising a stem (4), a socket (5), and a rectangular strip (1) with two or more tongues (3) for increasing the surface areas of electrical contact between the plug and socket and for approximately doubling the transmitted power, in which the stem (4) is fixed at one of its ends to the centre of said strip and at its other end is in contact with the socket (5), characterised in that the electrical contact is made by way of approximately semi-circular surfaces.

Drawing