GB2185156A - Pin shields on electric plugs - Google Patents

Abstract

Each of the contact pins (3) of a plug is provided with insulation (1) extending axially from the plug housing (4) to cover a part of the contact pin (3) and having the same external dimensions as the remainder of the contact pin (3), and is characterised in that the insulation (1) is formed integrally with the housing (4), preferably by injection moulding. This allows simple and economic production of the plug. The insulation (1) may be provided with a guide (2) serving to secure the position of the contact pin (3) in the radial direction. <IMAGE>

Description

SPECIFICATION Electric plug The present invention relates to a multi-pole electric plug for connection to an outlet socket and comprising an insulating housing, current-carrying contact pins projecting from said housing and means for connecting a cable to said contact pins within the housing. The contact pins will normally be of non-circular cross-section.

In electrical plugs of this kind, it is known to provide each current-carrying contact pin with a separate insulation extending axially around a part of the contact pin starting at the housing and having the same outer dimensions as the remainder of the contact pin, the end of the insulation remote from the housing abutting againstaflatshoulderonthe contact pin. The contact pin, together with its insulation, is secured in form-locking manner in the housing.

This way of arranging the insulations on the plug contact, and the subsequent attachment of the plug contacts, together with their insulations, to the plug housing requires a relatively high manufacturing outlay and is therefore uneconomical.

It is an object of the present invention to provide an electric plug of the kind referred to above in which these disadvantages are overcome and simple and economical production, particularly of the insulations, is ensured, and it is also ensured that the contact pins are fixed in position as far as their external dimensions relative to the external dimensions of the insulations are concerned.

According to the invention, there is provided a muiti-pole electric plug for connecting to an outlet socket, comprising an insulating housing, current-carrying contact pins projecting from the housing and means for connecting the conductors of a cable to said contact pins, each said current-carrying contact pin being provided with an insulation surrounding a part of said pin and extending axially from the housing and having the same outer dimensions as the remainder of said contact pin, the insulations for the current-carrying contact pins being formed integ rally with said housing.

The advantages of the invention consist not only in the simple, expedient and economical production of the insulationsforthe contact pins at the same time as the production of the plug housing, but also in the axial guide extending from and fixed to the housing which is provided axially in the insulation and which serves two fixthe position of the contact pin in the radial direction.

The invention will now be further described with reference to the drawing, in which Figure lisa schematicfrontviewofan electric plug according to the invention; and Figure2 is a schematic side sectional viewofthe plug of Figure 1, taken axially through one ofthe current-carrying contact pjns.

The plug, onlythe essential features of which have been shown in Figure 1, comprises a plug housing 4 on which insulations 1 for the two current-carrying contact pins 3 are arranged, the insulations being formed integrally with the housing. The contact pins 3 are arranged in the respective inqulations 1, and are secured in position therein in forc locking fashion.

An earth contact pin is shown at 5.

As can be seen from Figure 2, the insulations 1, which extend over only a part ofthe full length ofthe contact pins 3, form an integral partofthe housing 4; preferably, the housing and the integral insulation are injection moulded. The insulations 1 are provided with guides 2 extending in the axial direction so as to secure the position of the contact pins 3 in the radial direction, the contact pins 3 being secured in force-locking fashion in the axial direction atthe outer end bya shoulder6and atthe innerend by a rivet attachment, provided with an electrical terminal 7.

Instead of being produced by injection moulding, the housing 4, together with the insulations 1, can also be produced from an insulating material using the casting technique.

1. A multi-pole electric plug for connecting to an outlet socket, comprising an insulating housing, current-carrying contact pins projecting from the housing and means for connecting the conductors of a cable to said contact pins, each said current-carrying contact pin being provided with an insulation surrounding a part of sjid pin and extending axially from the housing and having the same outer dimensions as the remainder of said contact pin, the insulations for the current-carrying pins being formed integrally with said housing.

2. An electric plug as claimed in Claim 1,wherein each said insulation is provided with an axially extending guide serving to secure the position of the contact pin in the radial direction.

3. An electric plug as claimed in Claim 1 or Claim 2, wherein said housing and said insulations are formed integrally by injection moulding.

4. An electric plug substantially as hereinbefore described with reference to and as shown in the drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Electric plug The present invention relates to a multi-pole electric plug for connection to an outlet socket and comprising an insulating housing, current-carrying contact pins projecting from said housing and means for connecting a cable to said contact pins within the housing. The contact pins will normally be of non-circular cross-section. In electrical plugs of this kind, it is known to provide each current-carrying contact pin with a separate insulation extending axially around a part of the contact pin starting at the housing and having the same outer dimensions as the remainder of the contact pin, the end of the insulation remote from the housing abutting againstaflatshoulderonthe contact pin. The contact pin, together with its insulation, is secured in form-locking manner in the housing. This way of arranging the insulations on the plug contact, and the subsequent attachment of the plug contacts, together with their insulations, to the plug housing requires a relatively high manufacturing outlay and is therefore uneconomical. It is an object of the present invention to provide an electric plug of the kind referred to above in which these disadvantages are overcome and simple and economical production, particularly of the insulations, is ensured, and it is also ensured that the contact pins are fixed in position as far as their external dimensions relative to the external dimensions of the insulations are concerned. According to the invention, there is provided a muiti-pole electric plug for connecting to an outlet socket, comprising an insulating housing, current-carrying contact pins projecting from the housing and means for connecting the conductors of a cable to said contact pins, each said current-carrying contact pin being provided with an insulation surrounding a part of said pin and extending axially from the housing and having the same outer dimensions as the remainder of said contact pin, the insulations for the current-carrying contact pins being formed integ rally with said housing. The advantages of the invention consist not only in the simple, expedient and economical production of the insulationsforthe contact pins at the same time as the production of the plug housing, but also in the axial guide extending from and fixed to the housing which is provided axially in the insulation and which serves two fixthe position of the contact pin in the radial direction. The invention will now be further described with reference to the drawing, in which Figure lisa schematicfrontviewofan electric plug according to the invention; and Figure2 is a schematic side sectional viewofthe plug of Figure 1, taken axially through one ofthe current-carrying contact pjns. The plug, onlythe essential features of which have been shown in Figure 1, comprises a plug housing 4 on which insulations 1 for the two current-carrying contact pins 3 are arranged, the insulations being formed integrally with the housing. The contact pins 3 are arranged in the respective inqulations 1, and are secured in position therein in forc locking fashion. An earth contact pin is shown at 5. As can be seen from Figure 2, the insulations 1, which extend over only a part ofthe full length ofthe contact pins 3, form an integral partofthe housing 4; preferably, the housing and the integral insulation are injection moulded. The insulations 1 are provided with guides 2 extending in the axial direction so as to secure the position of the contact pins 3 in the radial direction, the contact pins 3 being secured in force-locking fashion in the axial direction atthe outer end bya shoulder6and atthe innerend by a rivet attachment, provided with an electrical terminal 7. Instead of being produced by injection moulding, the housing 4, together with the insulations 1, can also be produced from an insulating material using the casting technique. CLAIMS

1. A multi-pole electric plug for connecting to an outlet socket, comprising an insulating housing, current-carrying contact pins projecting from the housing and means for connecting the conductors of a cable to said contact pins, each said current-carrying contact pin being provided with an insulation surrounding a part of sjid pin and extending axially from the housing and having the same outer dimensions as the remainder of said contact pin, the insulations for the current-carrying pins being formed integrally with said housing.

2. An electric plug as claimed in Claim 1,wherein each said insulation is provided with an axially extending guide serving to secure the position of the contact pin in the radial direction.

3. An electric plug as claimed in Claim 1 or Claim 2, wherein said housing and said insulations are formed integrally by injection moulding.

4. An electric plug substantially as hereinbefore described with reference to and as shown in the drawing.