IE78623B1

IE78623B1 - Insulation displacement contact element

Info

Publication number: IE78623B1
Application number: IE922555A
Authority: IE
Inventors: Andrzej Janczak
Original assignee: Krone Ag
Priority date: 1991-08-02
Filing date: 1992-07-31
Publication date: 1998-02-25
Also published as: EP0525457A2; ATE135142T1; EP0525457B1; DE59205550D1; DK0525457T3; GR3019244T3; DE4126068C1; EP0525457A3; ES2084885T3; IE922555A1

Abstract

The invention relates to an insulation-piercing terminal contact element 1 for the insulation-free connection of an electrical conductor 2, especially in telecommunications and data technology, consisting of metallic leaf-spring material having two contact limbs 4, 5, which are separated along the contact slot 3 and are rigidly connected to one another via an end part 6, at their one end. In order to achieve greater stiffness of the insulation-piercing terminal contact element 1 with the contact slot 3 at the same time having a very small width in the quiescent state, the contact limbs 4, 5 are displaced approximately through half the material thickness D of the leaf-spring material to its front and rear side 9, 10, the contact edges 11 of the contact limbs 4, 5, which contact edges bound the contact slot 3, being arranged parallel to one another over their entire length. <IMAGE>

Description

INSULATION DISPLACEMENT CONTACT ELEMENT The invention relates to an insulation displacement contact element for the stripless termination of electrical conductors, in particular in the communica5 tion and data technique, made of metal blade-spring material and comprising two contact legs being separated along the contact slot and being rigidly connected with one another at one of their ends.

An insulation displacement contact element of the 10 type referred to hereinbefore is known in the art from DE 33 11 447 Al. Therein, the contact slots limiting the contact slot are interlaced with one another, so that an additional torsional force acts upon the clamping position. It is disadvantageous, therein, that by the interlacing of the two contact legs with each other, an acute-angled, V-shaped contact slot is formed, which, due to its different widths in the longitudinal direction of the contact slot, does not permit a uniform contact when terminating electrical con20 ductors, in particular very thin wires or strands.

Bending-up of the two contact legs and, thus, opening of the contact slot will be the larger, the deeper the electrical conductor is pressed into the contact slot. The opening width of the contact slot in the entry po25 sit ion depends upon the length of the contact slot, and is the larger, the longer the length of the contact slot is. Finally, relatively large bending-off of the contact legs will result when terminating electrical conductors; thus relatively high forces acting upon the housing receiving the insulation displacement contact element. Such forces are further increased by the existing additional torsional force.

From GB-A-2210514 there is known in the art a termination element being equipped with three or more prongs between which free spaces are provided. The free spaces have different widths in order to terminate different cable diameters. By forming V-shaped contact slots a relatively large deformation of the contact legs takes place when terminating the cable wires, thus relatively high forces being generated.

Is is therefore the object of the invention to improve an insulation displacement contact element of the type referred to hereinbefore such that a relatively uniform contact force is present for the termination of electrical conductors over the full length of the contact slot.

For the solution of this object, the invention provides that the contact legs are displaced each by approximately half the material thickness of the blade-spring material towards the front and rear sides thereof, the contact edges limiting the contact slot being disposed in parallel to one another over their full length. Thereby, a uniform width of the contact slot over its full length is obtained, thus the width of the contact slot being in the order of 0 to 0.05 mm. This allows contacting of very thin wires and strands as electrical conductors. Further, a very high rigidity of the insulation displacement contact element is obtained, without high forces acting upon the housing receiving the insulation displacement contact element.

In another embodiment the contact legs are twisted relative to one another by approximately half the material thickness of the blade-spring material, the contact edges of the contact legs limiting the contact slot being disposed in parallel to one another over their full length. Here, too, an extremely small width of the contact slot is achieved, so that very thin wires or strands can safely be terminated as electrical conductors. Further, a higher rigidity of the in3 sulation displacement contact element is obtained, without forces acting upon the housing receiving the insulation displacement contact element.

In the following, the invention is described in more detail, based on two embodiments of an insulation displacement contact element according to the invention represented in the drawings. There are: Fig. 1 the first embodiment of the insulation displacement contact element in a front view, a side view and a top view, Fig. 2 the insulation displacement contact element according to Fig. 1 with an electrical conductor terminated at 45°, Fig. 3 various possible contact positions of the insulation displacement contact element according to Figs. 1 and 2, Fig. 4 the second embodiment of the insulation displacement contact element in a front view,- a side view and a top view, Fig. 5 the insulation displacement contact element according to Fig. 4 with an electrical conductor terminated at 45°, and Fig. 6 various possible contact positions of the insulation displacement contact element according to Figs. 4 and 5.

The insulation displacement contact element 1 for the stripless termination of electrical conductors 2, comprises a metal blade-spring material of thickness D, being divided by a contact slot 3 extending over part of the full length into two contact slots 4, 5, rigidly connected to one another with a common end portion 6. The contact slot 3 extends from the bottom of the step-wise, approximately V-shaped entry section 7 to the upper end of an oval relief opening 8 in the transition section of the two contact legs 4, 5 to the end portion 6. The insulation displacement contact element 1 shown in Fig. la in a front view is made in a stamping process, whereby the entry section 7, the contact slot 3 and the relief opening 8 are formed.

In another production step, which can be executed together with the stamping process, the contact legs 4, 5 are each displaced by half the material thickness D of the blade-spring material towards the front and rear sides 9, 10 thereof, the contact edges 11 of both contact legs 4, 5 limiting the contact slot 3 being disposed in parallel to one another over their full length. During this process, the two contact legs 4, 5 are displaced in the area of the relief opening 8 to the front or rear sides 9, 10, resp., of the insulation displacement contact element 1, thereby displacement zones 12 resulting, which are disposed approximately in the central longitudinal area of the relief opening 8. By such displacement of the contact legs 4, 5 relative to one another by half the material thickness D of the blade-spring material each, -an extremely small width of the contact slot 3 between the contact edges 11 of both contact legs 4, 5 is obtained, which is in the order of 0 to 0.05 mm. In contrast thereto, with the traditional stamping processes of spring materials for insulation displacement contact elements, slot widths only are obtainable, which are greater than 0.7 times the material thickness of the spring material, which is usually 0.3 to 0.5 mm.

The insulation displacement contact element 1 allows for safe contacting of copper wires of 0.25 to 0.90 mm diameter and also for safe contacting of stranded wires. The insulation displacement contact element 1 can be employed as a bifurcated contact or as a wrap contact, the angle of the plane of the insulation displacement contact element 1 relative to the conductor 2 being between 30° and 60°.

In Fig. 2, the most frequent contact position of 45° between the insulation displacement contact element 1 and the conductor 2 is shown. Fig. 3 shows var5 ious possible contact positions with angles between 90° and 30° for different applications. It is essential that in all applications, parallelity of the contact legs 4, 5 relative to one another is maintained.

In Fig. 4, the second embodiment of the insulation displacement contact element 1' is shown, including a contact slot 3' with contact legs 4', 5' limiting the latter. The entry section 7 and the relief opening 8 are present, in the same way as in the em10 bodiment according to Figs. 1 to 3. In contrast to the first embodiment, the contact legs 4', 5' are each rotated relative to one another by half the material thickness D of the blade-spring material, the contact edges 11 of the contact legs 4', 5' limiting the con15 tact slot 3 being disposed in parallel to one another over their full lengths. For this purpose, the contact legs 4' , 51 are twisted over their full lengths relative to the end portion 6' in the direction of the front and rear sides 9, 10, as is shown in Fig. 4c in the top view. A displacement of the contact legs 4', ' relative to one another does not take place. The twisting zone 13 is in the area of the relief opening 8, as is shown in Fig. 4a.

Fig. 5 shows the termination of a conductor 2 at the contact legs 4', 5' of an insulation displacement contact element 1' in the second embodiment in a 45° position. Fig. 6 shows various other possible contact positions between the 90° position (bifurcated contact) and the 30° position.

In both embodiments, a high rigidity of the insulation displacement contact element 1, 1' is obtained. There are only low forces acting upon the housing including the insulation displacement contact element 1, 1'. The width of the contact slot 3, 3' is in both em35 bodiments nearly zero, in the rest position.

Claims

1. PATENT CLAIMS

1. An insulation displacement contact element (1) for the stripless termination of electrical conductors, in particular in the communication and data technique, made of metal blade-spring material and comprising two contact legs (4, 5) being separated along the contact slot (3) and being rigidly connected with one another at their end, characterised by that the contact legs (4, 5) are displaced by approximately half the material thickness (D) of the blade-spring material towards the front and rear sides (9, 10) thereof, the contact edges (11) of the contact legs (4, 5) limiting the contact slot (3) being disposed in parallel to one another over their full lengths and the width of the contact slot (3) being in the order of 0 to 0.5 mm in the rest position.

2. An insulation displacement contact element (1') for the stripless termination of electrical conductors, in particular in the communication and data technique, made of metal blade-spring material and comprising two contact legs (4', 5') being separated along the contact slot (3') and being rigidly connected with one another at their end, characterised by that the contact legs (4 1 , 5 1 ) are twisted relative to one another by approximately half the material thickness (D) of the blade-spring material, the contact edges (11) of the contact legs (4' , 5') limiting the contact slot (3') being disposed in parallel to one another over their full lengths and the width of the contact slot (3 1 ) being in the order of 0 to 0.5 mm in the rest position.

3. An insulation displacement contact element for the stripless termination of electrical conductors, substantially as herein described with reference to the accompanying drawings.