FR2504346A1 - Automatic electric cable loom mfr. on work table - uses wire cutting and insertion into self stripping connectors and has operations carried out successively using carousel - Google Patents

Abstract

The X-Y(-Z) work table (1) carries fixed pegs (3) in predetermined positions corresp. to the cable loom design which is to be implemented. Self-stripping connectors (4) of conventional type are placed near the ends of the cable loom branches, under the stretched wires (6) and in advance of the extreme end pegs. The wires are cut and inserted automatically into the connectors by vertical displacement of the cutting tool (5). Electrical contact is effected automatically by piercing of the insulation of wires which are trapped between the edges of metallic connections. The connectors (4) accept wires of various sizes and numbers so that a specific motor vehicle cable loom can be formed in half the time taken by the conventional process of severance and insertion.

Description

Process for the automated production of bundles of electrical wires
The present invention relates to the automated manufacture of bundles of electrical wires of various calibers, in particular for wiring electrical circuits of motor vehicles.

Several manufacturing methods are known.

Conventional bundle manufacturing involves several separate workstations, including cutting wires, crimping stripped ends, preparing and assembling bundles, finishing and electrical control.

The drawbacks of this process lie precisely in the multiplicity of positions which require a large floor area, an abundant workforce and which cause difficulties in managing the workshop and maintaining a correct level of quality, particularly because of the wide variety of wires and components used in automotive wiring.

Automated manufacturing uses automatic machines for cutting modules, that is to say plies of several wires of the same length, connected at each end to connectors which are themselves clipped onto metal connections previously crimped at the stripped ends. sons.

Compared to conventional manufacturing, automated manufacturing allows for maximum time savings of around 20 to 30 percent. However, the manufacture of simple modules requires an artificial increase in the length and weight of wires compared to the requirements which would normally be necessary if a bundle were directly designed for the application envisaged.

Indeed, the module technique requires the use of additional interconnection boxes, at a high cost, to make the connections between the different modules with a view to producing a given electrical circuit.

There is also known an automated manufacturing more specifically used by aviation in which the wires are cut and the particular beams formed on a work table provided with nails or points around which the wires are guided and movable in two (XY) or three (XYZ) orthogonal directions, relative to the cutting and automatic wire positioning tools.

This technique limited to cutting and positioning operations has hitherto not been possible economically for automotive applications because of the need to then perform, on the table, the crimping operations of the metal connections at the ends of the wires and snap-in connectors, given the number and variety of connections on the same harness.

The purpose of the present invention is to be able to adapt automatic XY (or XYZ) table manufacturing to the automotive sector, by finding an economical solution to the problem of making diversified connections at the ends of the bundle.

The method according to the invention makes it possible to respond to this problem by proposing to combine the technique of automatic manufacture on an XY table with the use of insulation displacement connectors, with automatic piercing of the insulation of the wires, moreover known per se and available in trade.

The subject of the invention is therefore a method of manufacturing around woven bundles of various electrical wires, in particular for wiring electrical circuits of motor vehicles, characterized in that there are insulation displacement connectors on a work table with relative movements with respect to the wire placement head and the cutting tools, along two or three orthogonal axes and at the predetermined locations corresponding to the ends of the beam to be produced, in that the beam is formed, in known manner, by automatic guiding and winding of the wires around points fixed on the table and arranged behind the connectors, so as to obtain a comb and in that the wires are cut and their crimping is carefully insulated in the connectors by means of a tool successively covering each connector.

The method according to the invention also makes it possible to automatically carry out branches at certain points of the beam, by means of insulation displacement branch connectors.

By tailors, the different steps of manufacturing the bundle, namely in particular the placement of the connectors on the table, the positioning of the wires, the cutting and crimping of the wires in the connectors, the electrical control, the wrapping and beam evacuation, can be chained automatically on a carousel.

As can be understood, the use of insulation displacement connectors with insulation piercing eliminates the various crimping problems of the old metal connections and makes it possible to manufacture automobile harnesses on XY type tables, which makes it possible to achieve a significant saving in length. and weight of son and significantly reduce manufacturing times, including direct labor time.

In addition, the manufacturing of a beam on a single station simplifies the management of the workshop, reduces the necessary floor area as well as intermediate handling and improves the manufacturing quality.

The following description refers to the attached drawing in which - Figure I is a perspective view of the work table and the beam formed, - Figures 2 and 3 show, in perspective, one end of the beam respectively before and after crimping in a insulation displacement connector.

Figure I shows a work table I on which a bundle of wires is already formed by guiding the wire around and between points 3 fixed on the table, at predetermined locations corresponding to the diagram of the bundle to be produced.

The table used is of the XY or XYZ type, that is to say with relative displacements along two or three axes orthogonal relative to the tools for placing the wires (pon shown) and for cutting 5
According to a characteristic of the method according to the invention, there are insulation displacement connectors 4, known per se, in the vicinity of the ends of the branches of the bundle below the tensioned wires 6 and upstream of the extreme guide pins 3, then the wires are cut and crimped automatically in the connectors by vertical displacement of the cutting tool 5 shown, suitably positioned.

Figures 2 and 3 illustrate this rapid operation in detail.

The electrical contacts are made automatically by piercing the insulating sheath of the wires trapped between the sharp edges close to the metal connections 7.

This type of connector accepts wires in number and in various sizes, which makes it possible to use an XY table for the formation of a specific automotive type beam, by eliminating the conventional and tedious crimping operations of connections.

By way of nonlimiting example, a bundle composed of 145 wires, of which 115 wires are crimped automatically in insulation displacement connectors by the method according to the invention, the remaining wires being crimped manually by the conventional method, has made it possible to reduce the time of manufacturing from 36 minutes to 18 minutes, saving time in a ratio of I to 2. Depending on the complexity of the beam, it was possible to reduce the manufacturing time in a ratio of I to 3.

The industrial application of this process is not limited to automotive wiring but could be successfully considered in particular in household appliances and in general for all wiring requiring the manufacture of complex bundles of different wires and which can accept piercing connectors insulation.

Claims (3)

I. Process for the automated manufacture of harnesses (2) of various electrical wires, in particular for wiring electrical circuits of motor vehicles, characterized in that there are insulation displacement connectors (4) on a work table (I) at relative displacements with respect to the tools along two or three orthogonal axes and at the predetermined locations corresponding to the ends of the bundle (2) to be produced, in that the bundle is formed, in known manner, by automatic guidance and winding of the wires (6 ) around points (3) fixed on the table and arranged behind the connectors, so as to obtain a comb and in that the wires are cut and their insulation stripping crimped in the connectors by means of a tool ( 5) successively covering each connector (4). 2. Method according to claim 1, characterized in that leads are automatically made at certain points of the beam, by means of insulation displacement taps. 3. Method according to claims I and 2, characterized in that the different steps of manufacturing the bundle, namely in particular the positioning of the connectors, the positioning of the wires, the cutting and crimping of the wires in the connectors, the electrical control , the wrapping and the evacuation of the beam, are linked successively and automatically on a carousel.