EP0700575B1 - Winding head - Google Patents

Abstract

PCT No. PCT/DE94/00395 Sec. 371 Date Nov. 27, 1995 Sec. 102(e) Date Nov. 27, 1995 PCT Filed Apr. 8, 1994 PCT Pub. No. WO94/28562 PCT Pub. Date Dec. 8, 1994Device for producing a coil winding (33) from winding wire on a winding carrier (32) with a winding head (10) which has a wire guiding means (16) and is movable relative to the winding carrier (32) in which a wire connecting means (17) and a wire severing means (18) are provided in addition to the wire guiding means (16) as further integral parts of the winding head (10).

Description

The present invention relates to a device for producing a coil winding from winding wire on a winding support with a winding head having a wire guide device and movable relative to the winding support. Furthermore, the invention relates to a method which can be carried out by means of this device for producing an electrically conductive connection.

Devices of the type mentioned above can be used in the manufacture of coil arrangements in which a wire conductor is wound around the winding support by means of a winding head to form a coil winding and wire ends of the winding wire are connected to connection surfaces of the winding support or those of adjacent components. In order to establish the connection of the wire ends to the connection surfaces, other devices, namely a connecting device and a wire separating device, are required in addition to the winding head. In the manufacture of such a coil arrangement, the procedure can be such that first a wire end is connected to a connecting surface by means of the connecting device, then the actual coil winding is formed around the winding support by means of the winding head, and finally the running wire end of the winding wire is carried out by means of the connecting device is connected to a further connection surface and is severed by means of the wire cutting device. Such an arrangement for performing the above roughly explained method is described in more detail in the PCT application WO 93/09551 by the applicant.

The large number of devices involved in the manufacture of such a coil arrangement results in an overall complex structure in the known device, with correspondingly high manufacturing times resulting in particular from the distances to be covered by the winding head between the individual, locally installed manufacturing stations (connecting station, separating station).

The present invention has for its object to provide a generic device or a method that enables the most compact possible construction and a reduction in manufacturing times.

This object is achieved by a device with the features of claim 1.

In the device according to the invention, the wire guide device, the connecting device and the wire separating device are integral devices of the winding head. Such a device virtually creates a highly integrated winding head which, in addition to the actual wire guiding function when winding a wire conductor on a winding support, also simultaneously performs the functions of connecting the wire ends to the winding support or a separate connection surface support separate therefrom and the final wire cutting function. Due to the combination in a structural unit, the entire device is a compact arrangement, so that both in one and the same relative position with respect to the connection surface of the connection surface carrier Connection of the wire conductor to the pad as well as cutting the wire conductor can be done. As a result, there are no intermediate routes during the establishment of the connection, which arise from the fact that, in devices according to the prior art, the wire guide device must be guided from a connecting device to a separating device.

Although, as explained above, the device according to the invention is particularly suitable for producing coil arrangements, that is to say both for carrying out a winding process and for carrying out the connection technology, the device according to the invention can equally advantageously be used in general where it matters, at certain points To create connections between a wire conductor and a connection surface and to guide the wire conductor in the intermediate area with the winding / connecting device according to the invention, referred to here as the winding head, on a predetermined movement path from one connection point to the other connection point. In this case, a winding process does not have to be carried out in every case, but also with a corresponding axis control of the winding / connecting device, a meandering course in one plane or any other wire course between two connection points can be generated.

In a preferred embodiment of the device according to the invention, the wire guide device, the connecting device and the wire separating device are combined in one tool head, the actuating or delivery elements necessary for the individual devices being arranged outside the tool head. This structure means a miniaturization which enables the use of the device according to the invention even with the smallest connection areas, such as the connection areas of a chip which are only 100 micrometers x 100 micrometers as standard.

A wire deflection device is preferably assigned to the wire guide device, which enables a wire conductor which is supplied approximately parallel to the connecting device to be deflected transversely to the feed axis of the connecting device so that the wire conductor comes to rest between the connecting device and the connecting surface when the connection is made.

At this point it should be noted that the connection device is not limited to a particular type, but rather that any of the range of connection devices available, such as a thermode, a thermosonic connection device, a laser welding device etc., or a combination thereof , can be selected.

When using a laser welding device, such a device, as described in DE-OS 42 00 492, has proven to be advantageous, in which the laser power emitted by a laser source is conducted directly to the connection point by means of a glass fiber conductor. When such a laser welding device is used together with the device according to the invention, there is the particular advantage that the winding head itself does not have to be loaded by the device device forming the laser source, but can be arranged in a stationary manner from the winding head. The fiber optic cable can then be used as a connecting device be integrated into the winding head. This makes it possible to use a high-performance laser welding device in the device according to the invention without disadvantageously increasing its mass due to the device device mentioned above.

It is also possible to combine all or part of the wire guide device, the connecting device and the wire separating device to form a functional unit. For example, the wire guide device can be combined with the connecting device, for example in the case of a thermosonic bonding head as the connecting device, the wire is fed through a capillary in the bonding head. It is also possible, if necessary, to additionally integrate the separating device in a functional unit which is then composed of a wire guide device, connecting device and wire separating device. An example of this would be a thermosonic bonding head provided with a wire guide capillary, which also has a separating edge formed in the wire contact area. This would allow a high level of integration to be achieved.

The wire deflection device is preferably formed from a suction device acting transversely to the feed axis of the wire guide device. In this advantageous embodiment of the wire deflection device, only a suction air connection is required in the area of the connecting device for its implementation, which causes the wire conductor fed through the wire guide device approximately parallel to the feed axis of the connecting device to be deflected transversely to the feed axis of the connecting device as a result of the suction force, so that the connecting device can act on the wire conductor, for example by applying heat and pressure in the case of a thermode.

Another possibility is to provide a gripping device which can be pivoted transversely to the feed axis of the connecting device for the wire deflection device.

A possible embodiment of a wire deflection device, which is similar in principle, but still preferable in terms of the achievable compactness, consists in making the wire guide device itself pivotable transversely to the feed axis of the connecting device, in order then to cooperate with the connection surface of the connection surface carrier which the wire conductor strikes, to cause such a deflection of the wire conductor that the wire conductor comes to rest between the connecting device and the connection surface.

It proves to be particularly advantageous if the device according to the invention is constructed in such a way that the actuating or feed elements assigned to the individual devices are arranged in a tool head carrier which can be coupled to the tool head. This creates the possibility of performing a simple tool head change if necessary, in order to be able to couple, for example, particularly coordinated combinations of tool head devices. For example, depending on the combination of the materials of the wire conductor and the connecting surface, it may prove advantageous to use a connecting device of a certain type. For example, the thermocompression method for a connection on a connection surface of a Kapton film and for a chip connection surface have been found the Thermosonic process as advantageous, and a combination of these processes is also conceivable. Regardless of the choice of the connecting device, however, one and the same actuating or delivery element can always be used. Apart from a simple and quick tool head change, this has a favorable effect on the tool preparation costs.

There are various options for executing the actuating or delivery elements. For example, they can be designed as compressed air actuators, such as piston / cylinder units, or as solenoid actuators.

Furthermore, there is the advantageous possibility of providing a further wire guide device in addition to the wire guide device described above. This makes it possible to add an additive, such as gold or a gold alloy, as a bonding wire, for example if the materials of the wire conductor and connection pad are not compatible with the connection, in order to provide a secure, electrically conductive connection between the wire conductor and the one made of an aluminum surface to ensure existing pad.

This further wire guide device can be integrated in the connecting device.

A further advantageous measure, for example to establish or increase the connection compatibility between the wire conductor material and the pad material, can consist in providing a protective gas supply device in the area of the connection device.

Another possible alternative is to provide a vacuum device in the area of the connecting device, for example by surrounding the entire tool head with a vacuum bell.

The protective gas supply device can also be assigned a coating device which enables an application of a protective layer to the connection point, for example the application of a passivation layer as corrosion protection, preferably while the protective gas is being applied to the connection point.

To monitor and / or control the device according to the invention, in a special embodiment it can be provided with a camera, in particular a CCD camera equipped with CCD (charge-coupled device) image sensors, which is attached to the tool head itself or also to the tool head carrier can. Depending on the type of attachment, the camera can also be integrated into the tool head or the tool head carrier.

The method according to the invention made possible by using the device according to the invention has the features of claim 17.

According to the invention, the device according to one or more of claims 1 to 16 is used to connect a bondable wire conductor directly to the unbumped connection areas of an electronic component, such as a chip. Here, the wire is connected directly to the aluminum pads, without bumps having been applied to them beforehand. The consequence of this is a considerable simplification in the electrical connection of chips or components comparable in terms of connection technology.

It proves to be advantageous if a bondable winding wire, preferably a copper bonding wire, is used as the wire conductor. This makes it possible to use the device according to the invention only for winding coils, and then to use the same wire to establish a direct connection to an unbumped connection surface.

It proves to be particularly advantageous if the connection between the wire and the connection surface takes place in a protective gas atmosphere or under vacuum in order to increase the quality of the connection.

• Fig. 1 die erfindungsgemäße Vorrichtung in einer ersten Ausführungsform mit einem an einen Werkzeugkopfträger angekoppelten Werkzeugkopf;
• die in Fig. 2 dargestellte Vorrichtung in vergrößerter Teildarstellung nach dem Wickeln einer Spule und der Verbindung von Wickeldrahtenden auf Anschlußflächen eines Spulenträgers;
• Fig. 3 A bis 3 C den Werkzeugkopfträger in verschiedenen, zeitlich einander nachfolgenden Konfigurationen zur Ausbildung einer Drahtleiterverbindung;
• Fig. 4 eine schematische Darstellung des Werkzeugkopfes in einer ersten Variation des in Fig. 1 dargestellten Werkzeugkopfs;
• Fig. 5 eine schematische Darstellung des Werkzeugkopfs in einer weiteren Variation des in Fig. 1 dargestellten Werkzeugkopfs.

Preferred embodiments of the device according to the invention with an exemplary explanation of the method according to the invention are explained in more detail below with reference to the drawings. Show it:

• 1 shows the device according to the invention in a first embodiment with a tool head coupled to a tool head carrier;
• the device shown in Figure 2 in an enlarged partial view after winding a coil and the connection of winding wire ends on connection surfaces of a coil carrier.
• 3 A to 3 C show the tool head carrier in different configurations which follow one another in time to form a wire conductor connection;
• FIG. 4 shows a schematic illustration of the tool head in a first variation of the tool head shown in FIG. 1 ;
• 5 shows a schematic illustration of the tool head in a further variation of the tool head shown in FIG. 1 .

1 shows, in a first embodiment, a winding / connecting device 10 with a tool head carrier 11 and a tool head 12. The tool head 12 is detachably connected to the tool head carrier 11 by means of a connecting element 13 designed here as a connecting sleeve 13. For the releasable connection, the connecting sleeve 13 has in its end region facing the tool head carrier 11 an internal thread 14 which interacts with an external thread of the tool head carrier 11, not shown in detail.

The tool head 12 has a tool holder 15 with tool devices accommodated and guided therein, namely a wire guide device 16, a connecting device 17, a wire separating device 18 and a wire deflecting device 19.

In order to enable a feed movement of the wire guide device 16, the connecting device 17 and the wire separating device 18 in the direction of a feed axis 20, the devices mentioned are provided at their upper end in FIG. 1 with pneumatic piston / cylinder units 21, 22, 23 provided as feed members . Damping devices 25 can be provided between piston rods 24 of the piston / cylinder units 21, 22, 23 and the ends of the devices 16, 17, 18, as exemplified for the wire cutting device 18.

In this case, the devices 16, 17, 18 are not coupled directly to the piston / cylinder units 21, 22, 23 but via the damping devices 25.

The function of the winding / connecting device 10 will be explained in more detail below.

1 shows the winding / connecting device 10 in a winding configuration in which the wire guide device 16 is in a position advanced from the tool holder 15. In this case, a winding wire 26 or generally a wire with which, for example, a wire connection between two connection surfaces is to be created, is passed through the tubular wire guide device 16. In this configuration, the winding / connecting device 10 can be used in the usual way as a winding head which can be moved in one or more axes in space or generally as a wire guide head.

In order to use the winding / connecting device 10 shown in FIG. 1 to connect the wire 26 'to a connecting surface ( not shown in FIG. 1) after a winding process or with the free wire end 27 fixed in some other way, the tool head 12 first move in the direction of arrow 28 and the wire guide device 16 is moved into the tool head 12 by actuating the piston / cylinder unit 21. As a result, the wire 26 lies against the underside of the tool head, so that the connecting device 17 can be moved out of the tool head 12 until it lies against the connecting surface with the wire 26 being interposed. Depending on the distance of the tool head 12 from the connection surface, the winding / connecting device 10 as a whole can be advanced in the direction of the feed axis 20.

Depending on the type of connection device 17, this works, for example, with thermocompression or ultrasound excitation with or without simultaneous heating of the connection surface, as a result of which the wire 26 is connected to the connection surface. After the connection has been made, the separating device 18 is extended, which in the exemplary embodiment shown in FIG. 1 has the form of a separating knife in order to cut the wire 26 near the connection point.

This configuration of the winding / connection device 10 is shown in FIG. 2 . Here, the wire guide device 16 is in the retracted position and the connecting device 17 and the wire separating device 18 are in the advanced position.

Referring to FIGS. 3 A to 3 C are then still the configurations of the winding / connection device 10 when carrying out a wire connection, such as laying down the wire end to a pad prior to performing a subsequent winding operation or a wire connection between the pads, are described . In a departure from the illustration according to FIG. 1 in FIG. 3A, the wire guide device 16, the connecting device 17 and the wire separating device 18 are initially in a completely retracted position and release a channel 30 running transversely to the feed axis 20. The wire conductor 26 fed through the wire guide device 16 is brought into a position transverse to the infeed axis 20 by the wire deflection device 19 embodied here as a suction device, with its free wire end Wire feed can be prevented by the wire guide device by means of a clamping device. In addition to the clamping device, a device can also be provided for threading the wire into the wire guide device in an air-supported manner through nozzle flows.

Subsequently, as shown in FIG. 3B, the connecting device 17 is extended until it lies against a connecting surface 29 with the interposition of the wire 26. In this position, the wire 26 is now connected to the connecting surface 29.

In the following, as shown in FIG. 3C, the wire cutting device 18 is also extended so that the wire 26 can be separated by the cutting device 18 near the connection point. The severed wire end is then sucked off by the suction device 19.

2 shows an example of a possible application of the winding / connecting device 10 according to the invention in its use in the manufacture of a watch coil 31, which is used in electrically operated watches and which has a winding support 32 with a coil winding 33 arranged thereon. The connection surfaces of the watch coil 31 are formed by means of a so-called "Kapton film" 34, which consists of a plastic film with metallization layers 35, 36 applied thereon. 2 shows two connection points 37, 38 on the metallization layers 35, 36, at which winding wire ends 39, 40 are connected to the metallization layers 35, 36.

The watch coil 31 shown in FIG. 2 can be produced by means of the winding / connecting device 10 according to the invention by first, as shown in FIGS. 3 A, 3 B, 3 C , a first connection of the winding wire 26 to the first metallization layer 35 below Connection 37 is formed. The coil winding 33 is then carried out by superimposing a rotational movement of the winding support 32 about its longitudinal axis and a translational movement of the tool head 12 in the direction of the arrow 41 and finally of the wire 26 performed.

4 and 5 show schematic representations of alternative designs of tool heads.

4 shows a tool head 56 with a wire feed device 42 which can be pivoted about an articulation point 43 transversely to the feed axis 20 of the tool head. 4 shows the wire guide device 42 both in its winding position oriented essentially parallel to the feed axis 20 and in the pivoted state. The pivotability of the wire guide device 42 makes it possible to dispense with a separate deflection device. Rather, in the embodiment shown in FIG. 4 , the winding wire 26 is guided through a wire feed with the wire guide device 42 pivoted onto a connection surface 44 and deflected thereon. In this position, a connecting device 45 which can be advanced in the direction of the infeed axis can be moved up to the connection surface 44, the wire 26 between the connection surface 44 and a contact surface 46 of the connecting device 45 comes to rest.

In the exemplary embodiment shown in FIG. 4 , the connecting device 45 is designed such that a further wire guiding device 47, for example in the form of a channel, is formed in it in order to guide an additional wire 48 onto the connecting surface 44, so that the connection of the wire 26 with the connection surface 44 can take place simultaneously with the connection of the additional wire 48 to the connection surface 44. This additional wire 48 can be designed in such a way that the connection of poorly connectable or connection-incompatible materials of the wire 26 and the connection surface 44 is made possible. It is also possible to match the material of the additional wire 48 to the materials to be connected in such a way that special corrosion protection or insulation from the outside is provided. The wire cutting device was not shown in FIG. 4 .

5 shows in a further variant a schematically illustrated tool head 49 which, similar to the tool head 12 shown in FIG. 1 , has a wire guide device 50, a connecting device 51 and a wire separating device 52. In a departure from the exemplary embodiment shown in FIG. 1 , the tool head 49 has a deflection device 53 which consists of a gripping device which can be pivoted about an articulation point 54 belonging to the tool head 49. In order to bring the wire 26, which is guided downward out of the wire guide device 50, into a connecting position in which the wire comes to lie between the connecting device 51 and a connecting surface (not shown in more detail in FIG. 5) , the Wire 26 is picked up by a gripper 55 of the deflection device 53 and the held wire 26 with the gripper is pivoted about the articulation point 54 into its left position in FIG. 5 . Starting from this wire position, as described above in connection with FIGS . 3 B and 3 C , the wire 26 can then be connected to a connecting surface and the wire 26 subsequently cut.

Claims (20)

1. A device for manufacturing a coil winding from winding wire (26) on a winding support with a winding head (10) which comprises a wire guide device (16, 42, 50) and is movable relative to the winding support, with a wire connecting device (17, 45, 51) for producing an electrically conductive connection between the winding wire and a connection surface of a connection surface support (31) and with a wire separating device (18, 52), characterised in that, in addition to the wire guide device (16, 42, 50), the wire connecting device (17, 45, 51) and the wire separating device (18, 52) are provided as further integral units of the winding head (10).
2. A device according to claim 1, characterised in that the wire guide device (16, 42, 50), the wire connecting device (17, 45, 51) and the wire separating device (18, 52) are combined in a tool head (12, 49, 56), the actuating/feed members (21, 22, 23) of these devices being arranged outside the tool head.
3. A device according to claim 1 or 2, characterised in that the connecting device (17) 'is constructed as a glass fibre conductor, which is integrated in the winding head (10) and is connected to a laser source preferably arranged independently of the winding head (10).
4. A device according to one or more of the preceding claims, characterised in that a wire deflecting device (19, 53) is associated with the wire guide device (16, 42, 50) for deflecting the wire (26) in a direction transverse to the feed axis (20) of the connecting device (17, 45, 51).
5. A device according to one or more of the preceding claims, characterised in that the wire guide device (16, 42, 50), the connecting device (17, 45, 51) and the wire separating device (18, 52) are fully or partially combined to form an operational unit.
6. A device according to one or more of the preceding claims, characterised in that the wire deflecting device (19) is formed by a suction device acting transversely to the feed axis (20) of the connecting device (17).
7. A device according to one or more of claims 1 to 5, characterised in that the wire deflecting device (53) is formed by a gripping device which is pivotable transversely to the feed axis (20) of the connecting device (51).
8. A device according to one or more of claims 1 to 5, characterised in that, for deflecting the wire, the wire guide device (42) is pivotable transversely to the feed axis (20) of the connecting device (45).
9. A device according to one or more of the preceding claims, characterised in that the actuating/feed members (21, 22, 23) are arranged in a tool head support (11) which is couplable with the tool head (12, 49, 56).
10. A device according to one or more of the preceding claims, characterised in that the actuating/feed members (21, 22, 23) are constructed as compressed air actuating members.
11. A device according to one or more of claims 1 to 9, characterised in that the actuating/feed members (21, 22, 23) are constructed as solenoid actuating members.
12. A device according to one or more of the preceding claims, characterised in that a further wire guide device (47) is provided.
13. A device according to claim 12, characterised in that the further wire guide device (47) is integrated in the connecting device (45).
14. A device according to one or more of the preceding claims, characterised in that a protective gas supply device is provided in the region of the connecting device (17, 45, 51).
15. A device according to one or more of claims 1 to 13, characterised in that a vacuum device is provided in the region of the connecting device (17, 45, 51) for generating a vacuum in the connecting region.
16. A device according to one or more of the preceding claims, characterised in that a monitoring camera, more particularly a CCD camera, is provided on the tool head (12, 49, 56) or on the tool head support (11).
17. A method for manufacturing an electrically conductive connection between a wire conductor (26) and a connection surface (29, 44) of a connection surface support using a device according to one or more of claims 1 to 16, characterised in that the wire conductor (26), which is guided through the wire guide device (16, 47, 52), is connected to a bump-free connection surface (29, 44) of an electronic component, such as a chip.
18. A method according to claim 17, characterised in that a bondable winding wire, preferably a copper bonding wire, is used as the wire conductor (26).
19. A method according to claim 17 or 18, characterised in that the connection of the wire conductor (26) with the connection surface (29, 44) is effected in a protective gas atmosphere.
20. A method according to claim 17 or 18, characterised in that the connection of the wire conductor (26) with the connection surface (29, 44) is effected under vacuum.

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