WO1988003714A1

WO1988003714A1 - Electrical plug

Info

Publication number: WO1988003714A1
Application number: PCT/SE1987/000531
Authority: WO
Inventors: Bo Gullbrandsson
Original assignee: Bo Gullbrandsson
Priority date: 1986-11-12
Filing date: 1987-11-11
Publication date: 1988-05-19
Also published as: AU8237387A; SE8604845L; SE457301B; SE8604845D0

Abstract

An electrical plug intended for connection to electrical, aerial or similar sockets, and including a casing comprising at least two mutually joined parts (1a, 1b), contact pins (2, 3) being accommodated in the casing and projecting out from it. One pin (2) is fastened in one part (1a) and another pin (3) is fastened in the other part (1b). Both parts (1a, 1b) are joined to each other (at 4) for pivoting movement between an open state, in which the pins are uncovered, and a closed state, in which a conductor brought into contact with the pin in one of the casing parts is firmly clamped with the aid of pressure means (5, 6) associated with the other casing part.

Description

ELECTRICAL PLUG

DESCRIPTION

Technical Field

The present invention relates to electrical plugs intended for connection to electrical, aerial or similar sockets, and including a casing comprising at least two mutually joined parts, contact pins being accommodated in the casing and projecting out from it. Background Art

Plugs of the type mentioned above are already known in many different embodiments. The disadvantages burdening these embodiments are that they of en contain a relatively large number of loose parts, that they are often difficult to assemble and take apart, which is also time-consuming and requires the use of tools, and that they can be inserted and retained in the sockets even when their casing parts are not properly assembled. This last creating considerable risk to persons touching such a plug. Disclosure of the Invention

One object of the invention is to provide a plug of the kind described in the introduction, that comprises few parts, that is simple to assemble and put together without needing to use tools, that is cheap to manufacture and which it is impossible to insert in a socket if the casing parts are not properly put together. This object is achieved by the inventive plug displaying the distinguishing features disclosed in the characterizing portions of the accompanying claims. Description of Figures

Figure 1 illustrates an inventive plug in a partially closed state,

Figure 2 is an end view of the» plug in Figure 2 in a closed state,

Figure 3 is a view of the plug illustrated in Figures 1 and 2 in a completely open state, and Figure 4 is a view of details pertaining to the plug of Figures 1 - 3 with the plug in a closed state. Preferred Embodiment

The plug, which is intended for use with a socket in a conventional mains supply, comprises a plastics casing 1 , made in one piece, and two metal contact pins 2 and 3. The pin 2 is fastened in a part 1a of the casing, and the pin 3 in a second part lb of the casing. The parts la and 1b are hingedly connected to each other by a hinge 4, integral with the parts 1a and 1b.

The parts 1a and 1b are each provided with integral,, upstanding posts 5, 8 and 6, 9. Between the posts 8 and 9 an opening 10 has been made in the mutually adjacent ends of the respective casing parts 1a and 1b. In the case where the plug is made as an earthed plug for a mains supply, metal tabs 11 and 12 are fastened to the parts 1a and 1b, so that they project outwards as well as inwards into the casing. A metal post 7 is connected to the tab 11 and is upstanding from the part 1b. -The part 1b is provided with a flexible hook 13, which is suitably integral with this part. In the closed state of the plug, the hook 13 engages in a groove 14 in the part 1a, and is retained in this position by the elasticity of the hinge 4, which causes the parts 1a and 1b to be biassed away from each other. The hook 13 is accessible for being deflected outwards when the plug is to be opened.

The contact pins 2 and 3 are identically alike, and a slit is made in the end of each pin accommodated in the respective casing part. The pin 2 and its slit 2a are illustrated in Figure 4. The two tongues thus formed on each pin are springy and their opposing walls are suitably serrated.

When the plug is to be connected to the conductors of a lead, the parts 1a and 1b of the casing are given the positions illustrated in Figure 3. The lead, illustrated solely in Figure 1 and denoted S, is inserted from below in Figure 3 through the opening 10, a current-carrying conductor then being inserted in the slit 2a, of each of the respective pins 2 and 3, one of the conductors L being shown in Figure 4. In appropriate cases, an earth conductor (unillustrated) is applied to the tab 12, e.g. by its being inserted in a slit corresponding to the slit 2a. The parts 1a and 1b are then folded towards each other along the hinge 4, and pressed against each other until the hook 13 snaps into the groove 14, the parts then being locked together. In this state the posts 8, 9 are urged against the lead S to prevent it moving in relation to the plug, and the posts 5, 6 are urged against the pins 3, 2, reducing the slits in them and firmly clamping the conductors in the slits to the pins. Where there is an earthing conductor, the post 7 clamps it against the tab 12, to which it has been applied. Should the parts 1a and 1b not be locked to each other by the elements 13 and 14, the pins 2 and 3 cannot be inserted in the holes in the socket, since they are attached to different casing parts and are therefore situated at a mutual spacing exceeding that of the holes in the socket. Neither can the portions of the pins 2, 3 in the casing be uncovered when the plug has been inserted in a socket, since the pins are each in a different part of the casing. The portions of the pins inside the casing can only be uncovered when the plug has been removed from the socket and the hook 13 has been urged away from the groove 14, the hook being accessible for this purpose via a portion of the groove 14.

Although only one embodiment of the invention has been described above and illustrated on the accompanying drawing, it will be understood that the invention is not ^• restricted to this eiribcdiment,but solely by the disclosures of the claims.

Claims

1. An electrical plug intended for connection to electrical, aerial or similar sockets, and including a casing comprising at least two mutually joined parts (1a, 1b) and contact pins accommodated in the casing and projecting out from it, both casing parts being joined to each other (at 4) for pivoting movement between an open state and a closed state, characterized in that a pin (2) is fastened in one casing part (1a) and another pin (3) is fastened in the other casing part (1b) , in that for the open state of the parts (1a, 1b) the pins fastened therein are uncovered and oriented in opposite directions, in that for the closed state of the parts the pins in them are directed in the same direction, and in that a conductor brought into contact with the pin on each part is firmly clamped, preferably by pressure means (5, 6) associated with the other part.

2. Plug as claimed in claim 1, characterized in that- the casing parts (1a, 1b) are made integrally, suitably of plastics material, and are hingedly joined to each other by a hinge (4) integral with the parts.

3. Plug as claimed in claim 1 or 2, characterized in that there is an opening (10) made at the joint (4) between the parts (1a, 1b), through which a lead (S) comprising a plurality of conductors (L) is insertable, and in that there is a pressure means (8, 9) on at least one of the parts and in the vicinity of the opening, for firmly clamping the lead in the closed state of the casing, said means suitably being integral with the casing part.

4. Plug as claimed in any one of the preceding claims, characterized by a lock means (13, 14) integral with the casing parts (1a, 1b) , the locking portions of the means being situated between both pins (2, 3) in the closed state of the casing parts.

5. Plug as claimed in any one of the preceding claims, characterized in that at least one of the pins (2, 3) is provided with a slit (2a) defined by at least one flexible wall, and in which a conductor (L) is insertable.