HARNESS MAKING APPARATUS

Description

[0001] The invention relates to a wire holding head and to a harness making apparatus comprising such heads.

[0002] In U.S. Patent Specification 4,428,114, there is described a harness making apparatus in which a row of connector parts are indexed along a feed path or guideway through a series of operating zones in each of which a wire holding head includes a device which forms a wire loop of desired length in a wire fed from a supply, severs the wire from the supply and terminates a leading and trailing end of the loop in terminals in the connector parts to form a harness. In practice, the wire holding heads form the loops on a side of the feed path remote from the wire supply to avoid entanglement during indexing of the connector parts along the feed path.

[0003] Using the above-described apparatus; harnesses including wires of any desired length terminated at. opposite ends in the connector parts can be progressively assembled during passage of the connector along the guideway.

[0004] However, for some applications, it is desirable to terminate the leading end of a wire in a terminal which is not in the row of connector parts.

[0005] It is an object of the invention to provide an improved wireholding head and harness marking apparatus.

[0006] According to the invention, a wire holding head comprising a loop-formirig device defining a semicircular loop-forming track and means to feed a leading end of a wire around the track to form a loop, shutter means being provided operable to close the track when forming a wire loop and to open the track and release the wire loop to permit unimpeded wire feed through the wire holding head by the wire feed means to extend the wire loop to a preselected harness length, characterised in that the wire holding head includes a straight track extending tangentially of the semicircular track, both tracks having a common entrance and pilot means operable to guide a leading end of wire either into the straight track or into the loop-forming track.

[0007] More particularly, the loop-forming device includes a semicircular loop-forming track and the head includes a straight track, the pilot means being operable to guide a leading end of a wire either into the semicircular track or the straight track. Preferably, the straight track extends tangentially of the semicircular track, both tracks having a common entrance, pilot means being located at the entrance and operable to permit a leading end of the wire to enter either track.

[0008] Desirably, the tracks are formed by grooves in a face of a body member and the pilot comprises a disc formed both with a straight and an arcuate groove, the disc being mounted for rotation in the body member between first and second alternative positions in which the arcuate groove and the straight groove are aligned with the entrance, respectively, thereby to guide a leading end of the wire into the semicircular groove or into the straight groove.

[0009] In a preferred construction, the grooves open downwards and the head includes shutter means movable between positions extending across the openings trapping wire in the grooves to permit wire feed and positions exposing the openings releasing wire therethrough to permit wire feed free of the tracks to form a loop of any desired length.

[0010] In a particular construction, the shutter means comprises a plurality of plate segments mounted adjacent the face of the body member, means being provided to move the segments between a contracted position in which they are located wholly within the semicircular track and an expanded position in which their peripheries extend across the opening.

[0011] Specifically, the plate segments comprise a front and rear pair of cam followers, one plate segment of each pair being symmetrically located on an opposite side of a medial axis of the semicircular track from the other plate segment of the respective pair and a cam member being mounted between the plate segments arranged for forward movement along the medial axis to cam the plates outwardly into the expanded position, with a leading edge portion of the cam plate extending across the opening between the front pair of plate segments.

[0012] The cam members comprise first and second cam plate portions fixed together by a pin passing through an axial slot in the body member to extend above and below the body member respectively, the first plate portion including a cam track receiving a cam follower pin passing through a transverse slot in the body member and fixed to the rear pair of plate segments and the second plate portion including cam surfaces engaging the front pair of plate segments.

[0013] This arrangement provides a relatively compact and reliable mechanism which can be operated by a conventional piston and cylinder assembly or other simple linear drive mechanism.

[0014] The invention also includes harness making apparatus comprising a frame providing a corrector quideway passing through a series of operating stations each of which includes a wire holding head according to the invention.

[0015] An example of the invention will now be described with reference to the accompanying drawings in which :

Figure 1 is a schematic perspective view of a harness making apparatus according to the invention ;

Figure 2 is an exploded perspective view of a wire holding head according to the invention ;

Figure 3 is an underplan of the wire holding head with a base plate omitted and with the track closed and a pilot in loop-forming condition ;

Figure 4 is a similar view to Figure 3 but with the track open and the pilot in straight wire lead out condition ;

Figure 5 is a cross-sectional view of the wire holding head with the track closed ;

Figure 6 is a fragmentary cross-sectional view of the pilot operating mechanism ;

Figure 7 is a fragmentary cross-sectional view taken along an axis perpendicular to the section of Figure 6 ;

Figure 8 is a perspective view of a loop-forming unit of a wire holding head ;

Figure 9 is an elevational view of part of the wire holding head and associated wire terminating mechanism;

Figure 10 is a schematic elevational view of the wire guide and ejection mechanism in a wire- receiving position mounted on a crimping press aligned with the wire holding head ; and,

Figure 10a is a schematic perspective view of parts of the wire guide and ejection mechanism after ejection of a terminated wire.

[0016] As shown particularly in Figure 1, the harness making apparatus comprises a frame 11 defining a guideway 12 providing a feed path extending past a series of work stations 13, 13' and supporting a series of pallets 14, 14' carrying connector pairs 15, 15', respectively. A return path (not shown) for the pallets is located beneath the feed path. Forward and return pallet indexing mechanism 17 and 17' are mounted for vertical movement into alignment with entry ends of the feed and return paths, respectively. The connector feed apparatus is closely similar to that described in Italian Patent Application No. 24063A184 corresponding to US-A-4552260.

[0017] Each workstation 13, 13' is closely similar to that described in the above-mentioned application and in U.S. Patent No. 4,428,114, and comprises a wire holding head 21 having wire entry and exit ends aligned with a pair of wire insertion rams 22, 22' and wire feed means 23 (Figure 9). In operation, as in the above-described apparatus where the wire is to be terminated at both ends in connectors on the guideway, the wire holding head forms a loop 24 in a leading end portion of a wire 25 fed across the feed path from a supply, the ram 22' terminates a leading end of the wire in a preselected terminal of one of the connectors of the connector pair 15, 15', the head subsequently indexes into alignment with a preselected terminal of the other connector of the pair while releasing the wire loop from the head and feeding additional wire from the supply to increase the loop to desired length and the ram 22 severs and terminates the trailing end of the wire loop in a preselected terminal of the other connector of the pair. Additional wires are terminated in connector pairs at successive workstations enabling harnesses to be progressively fabricated as a connector pair is indexed along the feed path.

[0018] The present apparatus is a modification of the apparatus described in the above-mentioned patent specitications in that the wire holding head is operable to provide either straight lead of the leading end of the wire or to form a loop.

[0019] As shown particularly in Figures 2 through 8, the wire holding head includes a block 31 to a lower face of which is secured a body member 32 and a base plate 33. The lower face of the body member 32 is formed with two wire guiding grooves 34 and 35, one 34 being semicircular the other straight, extending tangentially to groove 34. A common wire entry groove 36 is also formed in the lower face and a disc-form pilot 37 having arcuate and straight grooves 38 and 39 on one face is mounted in an aperture 41 in the body member between the entry groove and the grooves 34 and 35 for rotation between positions in which the arcuate and straight grooves 38 and 39 are respectively aligned with the entry groove 36 to form a wire loop or provide a straight lead out of a leading end portion of a wire passing through the entry groove. As shown particularly in Figures 2, 6 and 7, rotation of the pilot between positions limited by the engagement of shoulder 40, 41' with a stop 50 on block 31 is effected by engagement of a pinion 43 extending axially from the disc with a rack 44 connected to a piston 45 extending through a bore in the block 31. The condition of the pilot is indicated by the position of an arm 46 carried by the shaft of the pinion relative to a pair of proximity switches 46 and 47 (Figure 8) mounted on the block.

[0020] The groove 34 is closed by a shutter mechanism 51 mounted between the body member 32 and the base plate 33. The shutter mechanism comprises front and rear pairs of identical plate segments 52 and 53, each plate segment being located on an opposite side of a medial axis from its pair. A lower cam plate 54 is mounted between the plate segments and is formed with an arcuate leading end from which extend cam surfaces 60. The lower cam plate 54 is fixed to an upper cam plate 55 by drive pins 56, 56' passing through axially extending slots 57 formed in the body member. The upper plate 55 is formed with cam slots 58 which receive cam following pins 59 fixed in rear plate segments 53 and which extend through a transverse slot 61 in the body member 32. The body member is formed with an axial channel 63 receiving the upper plate 55 in a sliding fit. Guide pins 65, 65' and 66 extend through the body member and are received in slots 67, 67' and 68, 68' in the rear plate segments 53 and lower and upper cam plates 54, 55 respectively.

[0021] The drive pins 56, 56' are seated at upper ends in sockets 77, 77' in pistons 78, 78' received in working cylinders 79, 79' formed in the block 31. The pin 56 is of increased height extending through an axial slot 81 in the block into operative association with proximity switches 82, 82' (Figure 8).

[0022] The front plate segments 52 are linked to each other by a return spring 86 and to the rear plate segments by return springs 87.

[0023] It will be apparent that operation of pistons 78, 78' will drive upper and lower cam plates 55, 54 forward such that cam slots 58 and cam surfaces 60, respectively, urge rear plate segments 53 laterally apart so that the peripheries of both close the semicircular groove. The cam plate 54 causes an initial pivotal movement apart of the adjacent tips of the front cam plates 52 and finally a lateral translational movement apart on full engagement of the cam surfaces, a leading portion of the cam plate filling the space left between the front plate segments completely to close the front portion of the groove.

[0024] A leading end of the wire may then be fed either along groove 34 or 35 according to the position of the pilot 37. Release of the wire to enable a loop of desired length to be formed is effected by withdrawal of the plate segments under the action of the return springs on release of pressure from cylinders 79, 79'.

[0025] In this manner, wires may be terminated selectively at both or one end in terminals of connectors on the guide path. Other leading ends can be crimped in terminals 81 applied by other tooling such as a crimping press 82 fixed to the frame and transversely displaced from the guide path, as illustrated schematically in Figure 1 and in Figures 10 and 10a.

[0026] The crimping press 82 includes a frame 83 defining a wire admitting aperture 84 opening laterally at a downstream side and conventional crimping dies 85 mounted for reciprocal movement together in alignment with the aperture. A wire ejection mechanism comprises a wire engaging arm 86 pivotally mounted on the frame for reciprocal swinging movement by a piston and cylinder 87 across the aperture 84 to eject a terminated wire from the crimping press. A wire guide mechanism 89 is mounted on the front of the frame to extend between the aperture 84 and the groove 35. in the head 21. The wire guide mechanism 89 comprises a bipartite funnel consisting of a lower half 92 fixed to the frame 83 and an upper half 91 pivotally mounted on the lower half 92 for movement by a piston and cylinder 93, mounted on the front of the frame, between open and closed wire entry and wire exit positions.

[0027] As shown in Figures 1 and 10, in the wire feed position the funnel parts 91 and 92 are closed together to define a wire guide extending into the frame aperture 84 and a wire 25 is fed to a terminal 81 located on the die anvil 85. In this condition, the ejection arm 86 is held upstream of the aperture 84. Subsequent to termination of the wire 25, the piston and cylinder 93 is operated to pivot the funnel part 91 to open the funnel on the downstream side and piston and cylinder 87 is operated to swing the ejection arm across the aperture 84 to engage and eject the terminated wire 25 laterally, in the downstream direction from the crimping press, as shown in Figure 10a. The wire guide and ejection arm are then returned to their wire feed conditions by the operation of their respective piston and cylinders.

[0028] The ejection mechanism is particularly advantageous as it ensures clearance of the terminated wire to permit unimpeded feed of a successive wire in spite of the very close pitch of the terminals in the connector.

[0029] Thus, a variety of harnesses can be manufactured automatically using the above-described apparatus.

Claims

1. A wire holding head comprising a loop-forming device (34, 51) defining a semicircular loop-forming track (34) and means (23) to feed a leading end of a wire (25) around the track (34) to form a loop, shutter means (51) being provided operable to close the track (34, 35) when forming a wire loop and to open the track (34, 35) and release the wire loop (24) to permit unimpeded wire feed through the wire holding head (21) by the wire feed means (23) to extend the wire loop (24) to a preselected harness length, characterised in that the wire holding head (21) includes a straight track (35) extending tangentially of the semicircular track (34), both tracks (34, 35) having a common entrance (36) and pilot means (37) operable to guide a leading end of a wire (25) either into the straight track (35) or into the loop-forming track (34).

2. A wire holding head according to claim 1, characterised in that the tracks (34, 35) are formed by grooves (34, 35) in a face of a body member (32) and the pilot (37) comprises a disc (37) formed both with a straight and an arcuate groove (39 and 38), the disc (37) being mounted for rotation in the body member (32) between first and second alternative positions in which the arcuate groove (38) and the straight groove (39) are aligned with the entrance, respectively, thereby to guide a leading end of the wire (25) into the semicircular groove (34) or into the straight groove (35).

3. A wire holding head according to claim 2, characterised in that the grooves (34, 35) open downwards, the shutter means (51) being movable between positions extending across the openings trapping wire (25) in the grooves (34, 35) to permit wire feed and positions exposing the openings releasing wire therethrough to permit wire feed free of the grooves (34, 35) to form a loop (24) of any desired length.

4. A wire holding head according to claim 3, characterised in that the shutter means (51) comprises a plurality of plate segments (52, 53) mounted adjacent the face of the body member (32), means being provided to move the segments (52, 53) between a contracted position in which they are located wholly within the semicircular groove (34) and an expanded position in which their peripheries extend across the groove opening.

5. A wire holding head according to claim 4, characterised in that the plate segments (52, 53) are arranged as a front and rear pair of cam followers, one plate segment (52 or 53) of each pair being symmetrically located on an opposite side of a medial axis of the semicircular track (38) from the other plate segment (52 or 53) of the respective pair and a cam means (55, 54) being mounted between the plate segments (52 and 53) arranged for forward movement along the medial axis to cam the plates (52 and 53) outwardly into the expanded position, with a leading edge portion of the cam plate (54) extending across the opening between the front pair of plate segments (52).

6. A wire holding head according to claim 5, characterised in that the cam means (55, 54) comprise first and second cam plate portions (55 and 54) fixed together by a pin (56) passing through an axial slot (57) in the body member (32) to extend above and below the body member (32) respectively, the first plate portion (55) including a cam track (58) receiving a cam follower pin (59) passing through a transverse slot (61) in the body member (32) and fixed to the rear pair of plate segments (53) and the second plate portion (54) including cam surfaces (60) engaging the front pair of plate segments (52).

7. A wire holding head according to any one of the preceding claims, characterised by second terminating means (82) displaced transversely of the guideways (12), wire guide means (89) extending between the wire holding head (21) and the terminating means (82) movable between closed and open conditions respectively, to guide a leading end of a wire (25) transversely of the guideway (12) from the wire holding head (21) into the second terminating means (82) and to release the terminated wire (25) to permit indexing movement of the terminated wire (25) along the feed path.

8. A wire holding head according to claim 6, characterised in that the wire guide means (89) comprises a bipartite tube (91, 92), the parts (91, 92) being pivoted together for movement about a longitudinal pivotal axis between the open and closed conditions.

9. A wire holding head according to claim 7 or 8, characterised in that the second terminating means (82) comprises a crimping press (82) with dies (85) mounted for relative vertical movement transversely of the direction of the feed path, means (86, 87) being provided to eject a terminated wire (25) from between the dies (85) subsequent to termination and movement of the wire guide means (91, 92) to an open condition.

10. A wire holding head according to claim 9, characterised in that the wire ejection means (86, 87) comprises an ejection arm (86) mounted on the crimping press (82) for movement between the crimping dies (85) and the wire (25) guide thereby eject a terminated wire (25) from the crimping press (82).

11. Harness making apparatus comprising a frame (11) providing a connector guideway passing through a series of operating stations (13, 13') each of which includes a wire holding head (21) as claimed in any preceding claim.

Ansprüche

1. Drahthaltekopf mit einer schlaufenbildenden Vorrichtung (34, 51), die eine halbkreisförmige Schlaufenbildungsbahn (34) definiert, und mit einer Einrichtung (23) zum Herumfördern eines in Bewegungsrichtung vorderen Endes eines Drahts (25) um die Bahn (34) zur Bildung einer Schlaufe, wobei eine Verschlußeinrichtung (51) vorgesehen ist, die derart betreibbar ist, daß sie die Bahn (34, 35) bei Bildung einer Drahtschlaufe schließt und die Bahn (34, 35) öffnet und die Drahtschlaufe (24) freigibt, um eine ungehinderte Drahtbeförderung durch den Drahthaltekopf (21) hindurch mittels der Drahtfördereinrichtung (23) zu ermöglichen, um die Drahtschlaufe (24) auf eine vorgewählte Kabelbaumlänge zu verlängern, dadurch gekennzeichnet, daß der Drahthaltekopf (21) eine tangential zu der halbkreisförmigen Bahn (34) verlaufende, gerade Bahn (35) aufweist und beide Bahnen (34, 35) einen gemeinsamen Eingang (36) sowie eine Führungseinrichtung (37) aufweisen, die derart betreibbar ist, daß sie ein in Bewegungsrichtung vorderes Ende eines Drahts (25) entweder in die gerade Bahn (35) oder in the Schlaufenbildungsbahn (34) einführt.

2. Drahthaltekopf nach Anspruch 1, dadurch gekennzeichnet, daß die Bahnen (34, 35) durch Nuten (34, 35) in einer Flachseite eines Körperelements (32) gebildet sind und die Führungseinrichtung (37) eine Scheibe (37) aufweist, in der sowohl eine gerade als auch eine bogenförmige Nut (39 und 38) ausgebildet sind, wobei die Scheibe (37) in dem Körperelement (32) zwischen einer ersten und einer zweiten, alternativen Position, in denen die bogenförmige Nut (38) bzw. die gerade Nut (39) mit dem Eingang ausgerichtet ist, rotationsmäßig bewegbar angebracht ist, um dadurch ein in Bewegungsrichtung vorderes Ende des Drahts (25) in die halbkreisförmige Nut (34) oder in die gerade Nut (35) einzuführen.

3. Drahthaltekopf nach Anspruch 2, dadurch gekennzeichnet, daß die Nuten (34, 35) nach unten offen sind und die Verschlußeinrichtung (51) zwischen Positionen bewegbar ist, in denen sie sich über die Öffnungen erstreckt und dadurch Draht (25) zur Ermöglichung einer Drahtbeförderung in den Nuten (34, 35) einschließt, sowie Positionen, in denen sie die Öffnungen freilegt und dadurch den Draht durch diese hindurch freigibt, um eine von den Nuten (34, 35) freie Drahtbeförderung zur Bildung einer Schlaufe (24) jeder gewünschten Länge zu ermöglichen.

4. Drahthaltekopf nach Anspruch 3, dadurch gekennzeichnet, daß die Verschlußeinrichtung (51) eine Mehrzahl von Plattensegmenten (52, 53) aufweist, die benachbart der Flachseite des Körperelements (32) angebracht sind, wobei eine Einrichtung vorgesehen ist zum Bewegen der Segmente (52, 53) zwischen einer zurückgezogenen Position, in der sie sich vollständig innerhalb der halbkreisförmigen Nut (34) befinden, und einer ausgefahrenen Position, in der sich ihre Ränder über die Nutöffnung erstrecken.

5. Drahthaltekopf nach Anspruch 4, dadurch gekennzeichnet, daß die Plattensegmente (52, 53) in Form eines vorderen und eines hinteren paares von Steuerflächenfolgern angeordnet sind, wobei das eine Plattensegment (52 oder 53) jedes paares in bezug auf das andere plattensegment (52 oder 53) des jeweiligen paares auf einer gegenüberliegenden Seite einer Mittelachse der halbkreisförmigen Bahn (38) symmetrisch angeordnet ist und wobei eine Steuerflächeneinrichtung (55, 54) zwischen den plattensegmenten (52 und 53) angebracht sowie zur Ausführung einer Bewegung nach vorne entlang der Mittelachse ausgelegt ist, um die platten (52 und 53) in ihre ausgefahrene Position steuerflächenartig nach außen zu bewegen, wobei sich ein in Bewegungsrichtung vorderer Randbereich der Steuerflächenplatte (54) über die zwischen dem vorderen paar von plattensegmenten (52) befindliche Öffnung erstreckt.

6. Drahthaltekopf nach Anspruch 5, dadurch gekennzeichnet, daß die Steuerflächeneinrichtung (55, 54) einen ersten und einen zweiten Steuerplattenbereich (55 und 54) aufweist, die durch einen durch einen axialen Schlitz (57) in dem Körperelement (32) hindurchgeführten Stift (56) derart aneinander angebracht sind, daß sie sich oberhalb bzw. unterhalb des Körperelements (32) erstrecken, wobei der erste Plattenbereich (55) eine Steuerflächenbahn (58) aufweist, die einen Steuerflächenfolgerstift (59) aufnimmt, der durch einen Querschlitz (61) in dem Körperelement (32) hindurchgeführt ist und an dem hinteren Paar von Plattensegmenten (53) befestigt ist, und wobei der zweite Plattenbereich (54) Steuerflächen (60) aufweist, die an dem vorderen paar von Plattensegmenten (52) angreifen.

7. brahthaltekopf nach einem der vorausgehenden Ansprüche, gekennzeichnet durch eine zweite Anschließeinrichtung (82), die in Querrichtung von den Führungsbahnen (12) verlagert ist, wobei eine Drahtführungseinrichtung (89) sich zwischen dem Drahthaltekopf (21) und der Anschließeinrichtung (82) erstreckt und zwischen einem geschlossenen und einem geöffneten Zustand bewegbar ist, um das in Bewegungsrichtung vordere Ende eines Drahts (25) in Querrichtung zu der Führungsbahn (12) von dem Drahthaltekopf (21) in die zweite Anschließeinrichtung (82) zu führen bzw. den mit einem Anschluß versehenen Draht (25) freizugeben, um eine Fortschaltbewegung des mit einem Anschluß versehenen Drahts (25) längs der Förderbahn zu ermöglichen.

8. Drahthaltekopf nach Anspruch 6, dadurch gekennzeichnet, daß die Drahtführungseinrichtung (89) eine zweigeteilte Röhre (91, 92) besitzt, deren Teile (91, 92) zur Ausführung einer Bewegung um eine in Längsrichtung verlaufende Schwenkachse zwischen dem geöffneten und dem geschlossenen Zustand gelenkig miteinander verbunden sind.

9. Drahthaltekopf nach Anspruch 7 oder 8, dadurch gekennziechnet, daß die zweite Anschließeinrichtung (82) eine Crimppresse (82) mit Druckstempeln (85) aufweist, die zur Ausführung einer relativen, in vertikaler Richtung erfolgenden Bewegung quer zu der Richtung der Förderbahn angebracht sind, wobei eine Einrichtung (86, 87) vorgesehen ist zum Auswerfen eines mit einem Anschluß versehenen Drahts (25) von zwischen den Druckstempeln (85) nach dem Anschließvorgang und der Bewegung der Drahtführungseinrichtung (91, 92) in einen geöffneten Zustand.

10. Drahthaltekopf nach Anspruch 9, dadurch gekennzeichnet, daß die Drahtauswerfeinrichtung (86, 87) einen Auswerfarm (86) aufweist, der an der Crimppresse (82) derart angebracht ist, daß er eine Bewegung zwischen den Crimpstempeln (85) und der Führung des Drahts (25) ausführen kann, um dadurch einen mit einem Anschluß versehenen Draht (25) aus der Crimppresse (82) auszuwerfen.

11. Kabelbaumherstellungsvorrichtung mit einem Rahmen (11), der eine Verbinder-Führungsbahn vorsieht, die durch eine Reihe von Bearbeitungsstationen (13, 13') hindurchläuft, deren jede einen Drahthaltekopf (21) nach einem der vorausgehenden Ansprüche beinhaltet.

Revendications

1. Tête de maintien de fil comprenant un dispositif (34, 51) de formation de boucle définissant une piste semi-circulaire (34) de formation de boucle et des moyens (23) destinés à faire avancer une extrémité avant d'un fil (25) le long de la piste (34) pour former une boucle, des moyens obturateurs (51) pouvant être manoeuvrés pour fermer la piste (34, 35) lors de la formation d'une boucle de fil et pour ouvrir la piste (34, 35) et libérer la - boude de fil (24) afin de permettre une avance sans entrave du fil à travers la tête (21) de maintien du fil par les moyens (23) d'avance de fil pour étendre la boucle de fil (24) jusqu'à une longueur de faisceau préalablement choisie, caractérisée en ce que la tête (21) de maintien de fil comporte une piste droite (35) s'étendant tangentiellement à la piste semi-circulaire (34), les deux pistes (34, 35) ayant une entrée commune (36) et des moyens pilotes (37) pouvant être manoeuvres pour guider une extrémité avant d'un fil (25) soit dans la piste droite (35), soit dans la piste (34) de formation de boucle.

2. Tête de maintien de fil selon la revendication 1, caractérisée en ce que les pistes (34, 35) sont formées par des gorges (34, 35) dans une face d'un élément de corps (32) et le pilote (37) comprend un disque (37) formé à la fois d'une gorge droite et d'une gorge incurvée (39 et 38), le disque (37) étant monté de façon à tourner dans l'élément de corps (32) entre des première et seconde positions alternées dans lesquelles la gorge incurvée (38) et la gorge droite (39) sont alignées avec l'entrée, respectivement, afin de guider une extrémité avant du fil (25) dans la gorge semi-circulaire (34) ou dans la gorge droite (35).

3. Tête de maintien de fil selon la revendication 2, caractérisée en ce que les gorges (34, 35) s'ouvrent vers le bas, les moyens obturateurs (51) étant mobiles entre des positions s'étendant à travers les ouvertures, emprisonnant un fil (25) dans les gorges (34, 35) pour permettre une avance du fil, et les positions mettant à découvert les ouvertures, libérant le fil à travers elles pour permettre une avance du fil libre par rapport aux gorges (34, 35) afin de former une boucle (24) de toute longueur souhaitée.

4. Tête de maintien de fil selon la revendication 3, caractérisée en ce que les moyens obturateurs (51) comprennent plusieurs segments de plaque (52, 53) monté à proximité immédiate de la face de l'élément de corps (32), des moyens étant prévus pour déplacer les segments (52, 53) entre une position contractée dans laquelle ils sont disposés en totalité à l'intérieur de la gorge semi-circulaire (34) et une position expansée dans laquelle leurs périphéries s'étendent à travers l'ouverture de la gorge.

5. Tête de maintien de fil selon la revendication 4, caractérisée en ce que les segments de plaque (52, 53) sont agencés sous la forme de paires avant et arrière de contre-cames, un segment de plaque (52 ou 53) de chaque paire étant placé symétriquement, sur un côté opposé d'un axe médian de la piste semi-circulaire (38) par rapport à l'autre segment de plaque (52 ou 53) de la paire respective et des moyens de cames (55, 54) étant montés entre les segments de plaque (52 et 53) et agencés pour se déplacer vers l'avant le long de l'axe médian afin de déplacer par action de came les plaques (52 et 53) vers l'extérieur jusque dans la position expansée, une partie de bord avant de la plaque de came (54) s'étendant à travers l'ouverture entre la paire avant de segments de plaque (52).

6. Tète de maintien de fil selon la revendication 5, caractérisée en ce que les moyens de cames (55, 54) comprennent des première et seconde parties de plaque de came (55 et 54) fixées l'une à l'autre par une goupille (56) passant dans une fente axiale (57) de l'élément de corps (32) afin de s'étendre au-dessus et au-dessous de l'élément de corps (32), respectivement, la première partie de plaque (55) présentant une piste de came (58) recevant un doigt suiveur de came (59) passant à travers une fente transversale (61) de l'élément de corps (32) et fixé à la paire arrière de segments de plaque (53), et la seconde partie de plaque (54) présentant des surfaces de came (60) portant contre la paire avant de segments de plaque (52).

7. Tête de maintien de fil selon l'une quelconque des revendications précédentes, caractérisée par des seconds moyens de terminaison (82) décalés transversalement aux chemins de guidage (12), des moyens (89) de guidage de fil s'étendant entre la tête (21) de maintien de fil et les moyens de terminaison (82) et pouvant se déplacer entre des conditions fermée et ouverte, respectivement, afin de guider l'extrémité avant d'un fil (25) transversalement au chemin de guidage (12) à partir de la tête (21) de maintien de fil jusque dans les seconds moyens de terminaison (82) et de libérer le fil terminé (25) pour permettre un mouvement d'indexage du fil terminé (25) le long du trajet d'avance.

8. Tête de maintien de fil selon la revendication 6, caractérisée en ce que les moyens (89) de guidage de fil comprennent un tube (91, 92) en deux parties, les parties (91, 92) pouvant pivoter ensemble afin de se déplacer autour d'un axe longitudinal de pivotement entre les conditions ouverte et fermée.

9. Tête de maintien de fil selon la revendication 7 ou 8, caractérisée en ce que les seconds moyens de terminaison (82) comprennent une presse à sertir (82) munie d'outils (85) montés de façon à exécuter un mouvement vertical relatif transversalement à la direction du trajet d'avance, des moyens (86, 87) étant prévus pour éjecter un fil terminé (25) d'entre les outils (85) après une terminaison, et un mouvement des moyens de guidage de fil (91, 92) vers une condition ouverte.

10. Tête de maintien de fil selon la revendication 9, caractérisée en ce que les moyens (86, 87) d'éjection de fil comprennent un bras d'éjection (86) monté sur la presse à sertir (82) pour se déplacer entre les outils de sertissage (85) et le guide du fil (25) afin d'éjecter un fil terminé (25) de la presse à sertir (82).

11. Appareil de fabrication de faisceaux comprenant un bâti (11) qui présente un chemin de guidage de connection passant par une série de postes de travail (13, 13') dont chacun comprend une tête (21) de maintien de fil selon l'une quelconque des revendications précédentes.

Drawing