EP0315763B1 - Device for the connection of free wire ends - Google Patents

Description

The invention relates to a device for connecting the free wire ends of a wire bundle by temperature-assisted pressing of a material strip that can be glued or welded to the plastic sheathing of the individual wires onto the wire ends lying parallel to one another, comprising a base plate, a wire support detachably held on the base plate, and a pressure device with a vertical adjustable base plate for a press ram.

A device of the type mentioned above is known which presses a film strip onto the wires aligned in the wire support by means of a hydraulically driven, heated ram in order to glue or weld the film strip to the sheaths of the wires and thus to a specific sequence of the wires fix. Pressure time and temperature of the ram can be set on a circuit. The wire support is designed as a sorting comb and is placed on a carrier element. This carrier element contains four holes on its underside, which together with four bolts located on the base plate define an exact working position of the wire support. The positioning of the support element is cumbersome because the bolts and the bores in the support element that receive them are not visible during the positioning process. Furthermore, by connecting the free wire ends in this machine, you get a cable strip with parallel aligned connected wires, which, however, are usually not the same length and in one the production expensive further operation must be cut to the same length.

In the known device, the position of the ram is set in the pressure position via height stops. The contact pressure is therefore not defined, but varies with different wire sizes. However, too little pressure can result in individual wires not being properly connected to the film strip, which would require expensive post-processing. Damage to the wires is possible if the pressure is too high. A defined contact pressure is therefore necessary during the connection process in order to ensure a reliable, reproducible connection of the wires.

The invention has for its object to provide a device of the type mentioned, which allows a safe and reproducible connection of the wires in such a way that the ribbon cable end thus formed can be attached to a connector without another operation.

The object is achieved in that the press ram is movably mounted on the carrier plate parallel to the pressing direction against spring force, and that a cutting device is arranged on the carrier plate for severing the wire ends projecting beyond the material strip. The cutting device preferably comprises a knife fastened to the carrier plate, the cutting edge of which is located between the rest position and the pressing position of the pressing surface of the press ram, the wire support having a cutout for receiving the knife during the pressing process.

Due to the design of the device according to the invention, the wires are clamped during the pressing process by the pressure surface of the press ram in the wire support and connected to one another via the material strips and, when the carrier plate is brought closer to the base plate, severed by the knife perpendicular to its longitudinal direction. This has the advantage that the connected wire ends form a straight edge, to which a plug can be attached without further work.

Since the ram is adjustable against spring force, it is in contact with the strands during the connection process with the pressure force defined by the spring tension, so that reliable, reproducible cable connections can be created regardless of the respective wire thickness.

By guiding the press ram on the support plate by means of a plurality of bolts attached to the press ram which penetrate the support plate, a stable, torsion-proof guidance of the press ram is ensured.

In an ergonomically advantageous embodiment of the device according to the invention, a sliding guide is attached to the base plate, which enables the wire support arranged on a slide to be moved parallel to the base plate between a working position in which the wire support is aligned with the press ram and a preparation position in which the wire support is positioned can be inserted into and removed from the device or in which the wire bundle can be inserted and removed. This has the advantage that the insertion of the wire support does not have to be cumbersome, possibly even dangerous, below the pressure device.

The sliding guide is easy to implement in such a way that the slide is guided on rails arranged on the base plate or a base plate of the sliding guide via a tongue and groove guide, the working position being defined by a stop located in the sliding path. The slide can have roller or ball bearings to make it easier to move. For easy removal of the slide from the sliding guide and its insertion into the sliding guide, one rail is extended towards the preparatory position relative to the other by at least the length of the slide measured in the sliding direction and connected at its end projecting beyond this to a bar directed perpendicular to the rails . The slide is inserted from the side along the bar, so that when the grooves and tongues of the guide and slide are aligned, the slide can be inserted into the guide without the risk of jamming due to inaccurate alignment of the slide relative to the guide.

In order to ensure a defined position of the carriage during the pressing process, despite the displaceability of the carriage, it is proposed according to the invention that the carriage contains passages parallel to the pressing direction, which are aligned in the working position of the carriage with recesses formed in the base plate of the sliding guide and bolts arranged on the carrier plate. In the pressing position, the bushings in the slide and the depressions in the base plate are penetrated by bolts arranged on the carrier plate. After the pressure device has returned to the rest position, the carriage can be moved in the guide again.

When handling the wire support, the wires can be accidentally released from the wire support by pulling on the wire bundle when the wires are inserted. This can be prevented by arranging a clamp or strain relief to fix the wire bundle on the slide.

In order to avoid impairment of the functionality of the device by cut-off wire ends lying around in the device, at least the side of the wire support, which points from the cutout intended for receiving the knife in the direction of the wire ends to be cut off, has clamping grooves for holding the cut-off wire ends.

If the wires are clamped too strongly or too weakly between the strain relief and the clamping grooves, it could happen that the wires slip out of the side of the slots of the wire support. In order to avoid this and to ensure that the wire ends are held securely on the wire support and can be placed on or removed from the wire support in a simple manner and in a short time, it is proposed that the holding device be opposite the bottom of the groove on the top of the wire support arranged grooves is deeper and that the grooves each have a constant deep groove base in a first section directed towards the wire ends for unclamped separation of the wires, which drops to a greater depth in a second section facing the holding device, in which the width the grooves are so much smaller than the wire cross section that the wires can be clamped in the groove.

Due to this design of the device, the wires are formed by the lower position of the holding device relative to the bottom of the groove on the top of the wire support Grooves biased towards the bottom of the groove and thereby clamped in the groove section with the deeper bottom of the groove. In this way, the wires are clamped between the deeper groove section of the wire support and the clamping grooves of a downstream clamping support for the wires and are thus securely held in the groove section of the wire support provided for separating the wires.

In the case of an easy-to-manufacture wire support with a good clamping effect, the slot profile is at least approximately V-shaped.

In order to obtain a good connection between the individual wires and the material strip, the wire support is advantageously designed such that the depth of the groove base in the first section corresponds essentially to half the wire diameter. As a result, there is sufficient plastic sheathing of the wires for contact with the material strip, while at the same time a sufficiently large section of the wires lies in the grooves, so that the wires cannot be displaced against one another.

In a development of the invention, a sorting comb with comb grooves for the presorting of at least two cores per comb groove is arranged between the holding device and the wire support, the groove base of the comb grooves being located below the groove base of the wire support. This sorting comb enables the wires to be pre-sorted, for example, according to certain color codes applied to the sheathing, which simplify the sorting of the individual wires into the grooves of the wire support.

The prestressing of the wires towards the bottom of the slot of the wire support and securing the wires against a pull on the wire bundle can be combined with one another in an advantageous manner if the holding device is designed as a strain relief.

Fig. 1

eine teilweise schematische perspektivische teilgeschnittene Gesamtansicht der Vorrichtung in Ruhestellung des Preßstempels,

Fig. 2

eine schematische teilgeschnittene Seitenansicht der Vorrichtung in Ruhestellung des Preßstempels,

Fig. 3

eine der Figur 2 entsprechende Darstellung mit dem Preßstempel in Andruckstellung,

Fig. 4

eine schematische Draufsicht des Schlittens mit Adernauflage gemäß einer ersten Ausführungsform,

Fig. 5

einen Querschnitt der in Figur 4 dargestellten Adernauflage senkrecht zu den Aderführungen im Auflagenbereich des Materialstreifens,

Fig. 6

einen Querschnitt der Adernauflage gemäß Figur 4 senkrecht zu den Aderführungen im Bereich der abzuschneidenden Aderenden,

Fig. 7

eine Aufsicht auf einen Schlitten gemäß einer zweiten Ausführungsform mit einer Haltevorrichtung für ein Adernbündel, einen Sortierkamm und zwei Adernauflagen,

Fig. 8

einen Querschnitt durch den Schlitten entlang Linie VIII-VIII in Figur 7 und

Fig. 9

eine perspektivische teilschematische Ansicht eines Teils der Adernauflage gemäß Figur 7

Further features and advantages of the invention will become apparent from the following description, which in connection with the accompanying drawings explains the invention using exemplary embodiments. Show it:

Fig. 1

FIG. 2 shows a partially schematic, perspective, partially sectioned overall view of the device in the rest position of the press ram,

Fig. 2

2 shows a schematic, partially sectioned side view of the device in the rest position of the press ram,

Fig. 3

2 a representation corresponding to FIG. 2 with the press ram in the pressure position,

Fig. 4

2 shows a schematic top view of the slide with wire support according to a first embodiment,

Fig. 5

3 shows a cross section of the wire support shown in FIG. 4 perpendicular to the wire guides in the support area of the material strip,

Fig. 6

3 shows a cross section of the wire support according to FIG. 4 perpendicular to the wire guides in the area of the wire ends to be cut,

Fig. 7

2 shows a top view of a carriage according to a second embodiment with a holding device for a wire bundle, a sorting comb and two wire supports,

Fig. 8

a cross section through the carriage along line VIII-VIII in Figure 7 and

Fig. 9

6 shows a perspective, partially schematic view of part of the wire support according to FIG. 7

The device shown in Figures 1 to 3 comprises a base plate 10 to which two guide rods 12 are fastened perpendicular to it. On the guide rods 12, a support plate 14 directed parallel to the base plate 10 for a press ram 16 is vertically displaceably mounted. For the displacement of the carrier plate 14, a pressure medium-operated working cylinder 18 is used, which is arranged on a cover plate 20 connected to the upper ends of the guide rods 12 and whose piston rod 22 passes through the cover plate 20 parallel to the guide rods 12 and engages on the carrier plate 14.

The press ram 16 is guided on the carrier plate 14 with the aid of bolts 24 directed parallel to the guide rods 12, which penetrate bores 26 in the carrier plate and are secured against falling out of the bore 26 by a collar 28 at the upper end. The ram 16 is biased downward by two helical compression springs 30 from the carrier plate 14. The helical compression springs 30 surround the bolts 24 and engage with their end near the carrier plate 14 in a coaxial to the bore 26 and compared to this larger-diameter recess 32. The ram 16 can be heated in a manner not shown, for example by resistance heating.

On the underside of the carrier plate 14, a knife 36 is also arranged on a block 34 in such a way that it is close to and parallel to a side surface 38 of the rectangular press ram 16, the cutting edge 40 of the knife 36 being shown in FIG. 1 and 2 shown rest position of the ram 16 is above the pressure surface 42 of the ram. The purpose of this arrangement is explained in more detail below.

On the base plate 10, a sliding guide, generally designated 44, is arranged for a carriage, generally designated 46, which carries a wire support 48. The sliding guide consists of a rectangular base plate 50 resting on the base plate 10, along the longitudinal sides of which two guide rails 52 and 54 are arranged. The guide rails 52 and 54 each have a groove 56 or 58 on their mutually facing sides, which are each intended to receive a spring 60 or 62 formed on the sliding carriage 46. At their rear ends in FIG. 1, the guide rails 52 and 54 are connected to one another by a stop bar 64 which extends along the shorter rectangular side of the base plate 50. A guide bar 66 extends along the rectangular side of the base plate 50 opposite the stop bar 64 and is only connected to the guide rail 54. The other guide rail 52 is shorter than the guide rail 54 by an amount A which is at least equal to the width B of the carriage 46, so that an opening is formed between the free end of the guide rail 52 and the guide bar 66 through which the carriage 46 transversely can be inserted into the sliding guide 44 to the longitudinal direction of the guide rails 52, 54.

The insertion of the slide 46 along the guide bar 66 enables the slide 46 to be brought into a preparation or starting position without tilting, from which it can then be moved between the guide rails 52 and 54 into the working or end position defined by the stop bar 64. A button 68 fastened on the upper side thereof serves for easier handling of the slide 46.

In order to lock the carriage 46 in its working position and thus prevent the wire support 48 from slipping while the pressing die 16 is being pressed, the carriage 46 has two through-bores 70 directed near two diagonally opposite corners perpendicular to its surface, which in the end position of the Align carriage 46 with recesses 72 in the base plate 50 of the sliding guide 44 and with pins 74 arranged on the underside of the carrier plate 14. When the carrier plate 14 is lowered, the pins 74 reach through the bores 70 of the slide 46 into the recesses 72 in the base plate 50 and thus immobilize the slide 46 in its working position.

The cuboid wire support 48 comprises two sections 76 and 78, which are separated from one another by an upwardly open slot 80. The section 76 has on its surface a plurality of parallel groove-shaped depressions 82 arranged next to one another, into which wires 84 of a cable 91 or wire bundle can be inserted, which are to be connected to one another by a film strip 86. On the surface of section 78, each groove-shaped depression 82 is continued by a clamping groove 88 which is trapezoidal in cross section and in which the end section 92 of the respective wire 84 is clamped (FIG. 6). On The carriage 46 is also arranged a cable clamp 90 shown in FIG. 4, which serves to hold the wire bundle or cable 91, the individual wires 84 of which are to be aligned on the wire support serving as a sorting comb. This is to prevent unintentional loosening of the wires 84 from the wire support 48 by pulling on the cable.

The device described so far works as follows:
The carriage 46 is inserted laterally with the wire support 48 already fitted in the sliding guide. The lateral recess in the sliding guide 44, which was created by shortening the guide rail 52 relative to the other guide rail 54, is used for this purpose. When the springs 62 of the carriage 46 have engaged in the grooves 58 of the guide rail 54, the carriage is pushed into the working position defined by the stop 64.

After the wire support 48 with the parallel aligned wires 84 and the overlying film strip 86 has been brought into the working position, the support plate 14 is lowered with the heated press ram 16 by actuating the working cylinder 18. The bolts 74 arranged on the support plate 14 penetrate the bushings 70 of the carriage 46 and the depressions 72 in the base plate 50 of the guide 44 and thereby hold the wire support 48 in the working position during the pressing process. The pressure surface 42 of the heated press die 16 presses the film strip 86 lying thereon onto the wires 84 aligned in the wire support 48, the film strip 86 being welded or glued to the wires 84. From the time at which the pressure surface 42 of the press ram 16 touches the film strip 86 lying thereon, it moves the cutting edge 40 of the knife 36 fixedly connected to the carrier plate 14 by further downward movement of the carrier plate 14 in the pressing direction past the pressing surface 42 of the press ram 16. The wire ends 92 held in the clamping grooves 88 are separated from the wires 84 clamped under the ram 16. The cutting knife 36 penetrates into the slot 80 formed in the wire support 48. The device remains in the pressure position for a pressure time to be individually set on the wires (FIG. 3). The pressing time and temperature of the ram 16 can be set on a control unit 94. A reset to the starting position (FIG. 2) is carried out by actuating the working cylinder 18 again. After the slide 46 has been pulled out of the working position into the preparation position, the slide 46 and the wire support 48 can be removed from the device. Another slide with the wire support already fitted can now be inserted into the device.

FIGS. 7 to 9 show a further embodiment of a carriage with wire supports, which is explained in more detail below, the same parts again being provided with the same reference numerals.

The rectangular slide 46 shown in FIG. 7 carries at one end the holding device or cable clamp 90 designed as a strain relief for the cable 9 or wire bundle 91. A sorting comb 96 is arranged between the holding device 90 and the first section 76 of the wire support 48. This has on its upper side parallel grooves 98 in which the wires emerging from the cable 91 are pre-sorted into smaller wire bundles which may be arranged according to color.

The first section 76 of the wire support 48 has on its upper side a plurality of grooves 82 which are directed parallel to one another and which are directed parallel to the comb grooves 98 of the sorting comb 96. A groove 82 on section 76 is assigned to each core of a core bundle coming from sorting comb 96. In a first length section remote from the sorting comb, the groove base 100 of the grooves 82 is parallel to the surface of the wire support 48, the depth T2 of the grooves being approximately equal to half the wire diameter. In a second length section directed towards the sorting comb 96, the groove base 100 of the grooves 82 of the first section 76 of the wire support 48 falls towards the sorting comb 96 in a region of length L from the lower depth T2 to a greater depth T1 (FIG. 9). The profile of the grooves 82 is V-shaped, the width of which is somewhat larger at the upper end and smaller in depth T1 than the wire diameter. As a result, the wires are clamped in the slot section with the length L in the slots 82. Since the groove bottom of the comb grooves 98 is deeper than the groove bottom 100 of the grooves 82 directed towards the sorting comb 96 (FIG. 8), the wires are drawn into the grooves 82. The wires are not clamped in the slot section facing the wire ends with the slot depth T2, but are isolated only for the application of a strip of material.

The second section 78 with V-shaped clamping grooves 88 is arranged downstream of the first section 76 of the wire support 48. These are directed parallel to the grooves 98, 82 of the sorting comb 96 or the first section 76. The free wire ends of the individual wires in the first section 76 are clamped in this second section 78. The veins are therefore between the groove section with the Length L of the grooves 82 and the clamping grooves 88 clamped, whereby the wires are securely fixed in the separation area of the grooves 82. Between the first section 76 and the second section 78 of the wire support 48, a space 80 is again formed for receiving the cutting knife 36.

Claims (13)

1. Apparatus for connecting the free ends of the cores of a bunch (91) thereof by temperature-assisted pressing of a strip of material (86) stickable or weldable to the plastic sheathing of the individual cores (84) on to the core ends disposed in parallel relationship, comprising a baseplate (10), a core support (48) releasably held on the baseplate (10), and a pressure application device (18) having a carrier plate (14) for a press ram (16), said carrier plate (14) being movable perpendicular to the baseplate (10), characterised in that the press ram (16) is mounted on the carrier plate (14) for movement against spring force and in parallel relationship to the pressure application direction, and in that a cutting device (36, 40) for severing the core ends (92) projecting beyond the strip of material (86) is provided on the carrier plate (14).
2. Apparatus according to claim 1, characterised in that the press ram (16) is guided on the carrier plate (14) by means of a plurality of bolts (24) extending through guide bores in the carrier plate.
3. Apparatus according to claim 1 or 2, characterised in that the cutting device comprises a knife (36) fixed on the carrier plate (14), the knife edge (40) being situated between the position of rest and the pressure application position of the pressure application surface (42) of the press ram (16), and in that the core support (48) has a recess (80) to receive the knife (36) during the pressure application operation.
4. Apparatus according to any one of claims 1 to 3, characterised in that a slideway (44) is provided on the baseplate (10) for a carriage (46) carrying the core support (48), said carriage (46) being displaceable in the slideway (44) in parallel relationship to the baseplate (10) between a preparatory position and an operative position in which the core support (48) is in alignment with the press ram (16) in the direction of pressure application.
5. Apparatus according to claim 4, characterised in that the carriage (46) is guided by means of a key and keyway guide on rails (52, 54) disposed on the baseplate (50) of the slideway (44), and in that the operative position is defined by a stop (64) disposed in the path of the sliding movement.
6. Apparatus according to claim 5, characterised In that one rail (54) as considered in the direction towards the preparatory position is longer, at least by the length of the carriage (46) measured in the sliding direction, than the other rail (52), and is connected, at its end projecting beyond said other rail, to a strip (66) extending perpendicularly to the rails (52, 54).
7. Apparatus according to any one of claims 4 to 6, characterised in that the carriage (46) contains passages (70) extending parallel to the direction of pressure application, such passages (70), in the operative position of the carriage (46), being in alignment with recesses (72) formed in the baseplate (50) of the slideway (44) and bolts (74) disposed on the carrier plate (14).
8. Apparatus according to any one of claims 1 to 7, characterised in that a holding device (19) intended to hold the bunch of cores (96) fast relatively to the core support (48) is provided.
9. Apparatus according to any one of claims 3 to 8, characterised in that the core support (48) has clamping grooves (88) to receive the core ends (92) at least on one side of the recess (80) intended to receive the knife, said clamping grooves (88) extending perpendiculary to said recess and parallel to one another.
10. Apparatus according to claims 1, 8 and 9, characterised in that the holding device (90) is lower than the base (100) of the grooves (82) formed on the top of the core support (48) and in that the grooves (82) respectively have a base (100) of constant depth in a first portion remote from the holding device (90) for the purpose of unclamped separation of the cores, said base (100) sloping down in a second portion directed towards the holding device (90) to a greater depth (T1) in which the width of the grooves (82) is so much smaller than the core cross-section that the cores can be clamped fast in the groove (82).
11. Apparatus according to claim 10, characterised in that the profile of the grooves (82) of the core support (48) is at least approximately V-shaped.
12. Apparatus according to claim 10 or 11, characterised in that the depth of the groove base (100) in the first portion of the grooves (82) of the core support (48) corresponds substantially to half the core diameter.
13. Apparatus according to any one of claims 10 to 12, characterised in that a sorting comb (96) having grooves (98) for presorting at least two cores per comb groove (98) is provided between the holding device (90) and the core support (48), the base of the comb grooves (98) being situated below the base (100) of the grooves (82) of the core support (48).

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