DEVICE FOR ELECTRICALLY CONDUCTIVE CONNECTING OF CONDUCTORS WITH A RETAINING DEVICE

Abstract

The invention relates to a device for electrically conductive connecting, by means of ultrasonic welding, of first electric conductors (140, 142) and second electric conductors (144, 146) in a compression space the cross section of which can be changed and which comprises at least one lateral slide, a sonotrode and a counter electrode, wherein firstly, blank ends of the first electric conductors (140, 142) are introduced into the compression space and are welded by means of ultrasonic action to form a first connection (148) and then after the first connection has been removed from the compression space, blank ends of the second electric conductors (144, 146) are introduced into same and are welded by means of ultrasonic action to form a second connection, wherein the first connection is fed to a retaining device (182, 184) before the second connection is welded.

Claims

1. A device for connecting first conductors and second conductors by ultrasonic welding, comprising: a lateral slide, a sonotrode, and a counter electrode defining a compression space; and a retention device located outside the compression space; wherein the retention device is configured with respect to the compression space such that when the compression space is open, the retention device keeps an inline splice of welded electrical conductors previously welded in the compression space out of the compression space.

2. The device according to claim 1, wherein the retention device is formed as a member selected from the group consisting of a recess, a protrusion, a bracket, a hook, a clamping device, a gripping element, a spring, and a downholder.

3. The device according to claim 1, wherein the retention device is formed as a recess in an upper side of the lateral slide, distal to a bottom surface of the compression space.

4. The device according to claim 3, wherein the recess has a cross sectional geometry in the form of a member selected from the group consisting of a triangle, a non-isosceles triangle, a rectangle, a segment of a circle, a semicircle, and a combination thereof, in a cross section taken perpendicular to a front surface of the lateral slide.

5. The device according to claim 1, wherein the recess is formed as an undercut.

6. The device according to claim 1, wherein a protrusion having a rectangular- or L-shape in cross section extends from an upper side of the lateral slide; and wherein a surface of the protrusion facing the compression space transitions flush with a surface of the lateral slide that delimits the compression space.

7. The device according to claim 1, wherein the retention device is formed as a recess in a front surface of the counter electrode that faces the lateral slide, or as a protrusion extending from the front surface of the counter electrode.

8. The device according to claim 7, wherein a lower surface of the protrusion transitions flush into a lower surface of the counter electrode, so that a section of the lower surface of the counter electrode delimits the compression space.

9. The device according to claim 1, further comprising a housing disposed around the compression space and the retention device.

10. The device according to claim 9, wherein the housing comprises a first section and a second section which is adjustable with respect to said first section; and wherein the retention device is in a form of a hook-shaped protrusion extending from the first section or the second section.

11. The device according to claim 10, wherein two mutually spaced retention devices extend on opposite sides of the compression space, when the housing is in a closed position.

13. The device according to claim 1, comprising a plurality of retention devices.

14. The device according to claim 9, wherein the housing comprises a base plate, and wherein the retention device extends from the base plate.

15. The device according to claim 1, wherein the retention device is formed in, or on, the lateral slide, or in, or on, the counter electrode.

Description

[0025] In the drawing:

[0026] FIG. 1 shows a schematic diagram of an ultrasound metal welding arrangement,

[0027] FIG. 2 shows a schematic diagram of a compression space of an ultrasound metal welding device,

[0028] FIG. 3a shows a schematic diagram of a first embodiment of a lateral slide,

[0029] FIG. 3b shows a schematic diagram of a second embodiment of a lateral slide,

[0030] FIG. 3c shows a schematic diagram of a third embodiment of a lateral slide,

[0031] FIG. 3d shows a schematic diagram of a fourth embodiment of a lateral slide,

[0032] FIG. 3e shows a schematic diagram of a fifth embodiment of a lateral slide,

[0033] FIG. 3f shows a schematic diagram of a sixth embodiment of a lateral slide,

[0034] FIG. 4a shows a schematic diagram of a seventh embodiment of a lateral slide,

[0035] FIG. 4b shows a schematic diagram of an eighth embodiment of a lateral slide,

[0036] FIG. 5 shows an ultrasound welding device with sound protection housing,

[0037] FIG. 6 shows an ultrasound welding device according to FIG. 5 with a sound protection housing of different design,

[0038] FIG. 7 shows the arrangement according to FIG. 6, in which first conductors of twisted conductors are welded,

[0039] FIG. 8 shows the arrangement according to FIGS. 6 and 7 with closed sound protection housing, and

[0040] FIG. 9-14 show additional embodiments of retention devices.

[0041] Based on the figures, in which basically identical elements are provided with identical reference numerals, the teaching according to the invention is explained, by means of which individual conductors or cables which are twisted together can be welded, without any untwisting or twisting occurring in the area of the connections, so that a mutual influencing of the electrical conductors or cables is reduced.

[0042] This is of particular interest in the sector of communication technology, but also in the motor vehicle sector. The avoided mutual influencing here has a positive effect particularly in a cable harness of a motor vehicle, since the susceptibility to failure of the cable harness is reduced.

[0043] FIG. 1 is a purely schematic diagram of an ultrasound welding arrangement 110 intended to explain essential elements. The arrangement 110 comprises an ultrasound metal welding device 111 which is intended for welding conductors or cables.

[0044] The ultrasound welding arrangement 110 comprises, as essential elements, a converter 112 and a sonotrode 114, between which a booster for amplitude amplification is arranged. The converter 112, the booster 116 and the sonotrode 114 form a so-called ultrasonic oscillator 117 which is mounted in the booster. Associated with the sonotrode 114, i.e., its head with welding surface, which cannot be seen in FIG. 1, is a counter electrode 115 also referred to as anvil, which can be lowered toward the oscillator 117, in order to introduce forces into the joining zones during the welding, in the present case for the formation of passage nodes of conductors or cables.

[0045] The anvil 115 is accommodated by a so-called surface plate 119 (see FIG. 2) which can be adjusted perpendicularly to the welding surface 1114 of the sonotrode 114. Opposite, a lateral slide 113 is present, which, with the anvil 115, the sonotrode 114 or its welding surface 1114, and the surface plate 119, delimits a compression space 121 the height and width of which are adjustable.

[0046] The converter 112 is connected via a line 118 to a generator 120 which in turn is connected via a line 122 to a computer. Via the generator 120, high-frequency voltage is applied to the converter 112, i.e., to the piezo crystal plates arranged therein, in order to expand or to contract the plates whereby ultrasonic oscillations with an amplitude which is amplified by the booster 116 and transferred to the sonotrode 114 are generated.

[0047] The oscillation frequency is typically 20 kHz, The half-wave amplitude is usually between 0.010 mm and 0.045 mm. The forces acting on the cables during the ultrasound welding, which act on the cables from the anvil 115, can be between 150 N and 3000 N. The welding surface extends in the oscillation trough of the ultrasonic oscillations.

[0048] Although, based on FIG. 1, a longitudinal oscillator has been explained, the teaching according to the invention is also not exceeded if a torsional oscillator is used.

[0049] The ultrasound welding device 111 moreover is usually surrounded by a sound protection housing 126 which is closed during the welding. Purely as an example, such a housing can be obtained from FIG. 5. The sound protection housing 126 here consists of a stationary section 128 and a section 130 which can be moved with respect to said stationary section and which, during the welding, adjoins said stationary section and is in turn surrounded by a housing part 132.

[0050] On the bottom side, the housing 126 is closed by a base plate 134, from which the components or tools start or are mounted, which, among other reasons, are necessary for the formation of the compression space 121. Such a compression space can be obtained purely schematically from FIG. 2. One can see the sonotrode 114 with welding surface 1114, the lateral slide 113, the anvil 115 and the surface plate 119 which surround the compression space 121.

[0051] The conductors to be welded are introduced into the opened compression space 121, in order then to move the lateral slide 113 in the direction of the surface plate 119 to the desired welding width. Then, the anvil 115 is moved in the direction of the lateral slide 113 with simultaneous lowering by adjustment of the surface plate 119, in order then to weld the conductors after contacting of said conductors with sonotrode 114 excited. To that extent, reference is made to sufficiently known techniques.

[0052] According to the invention, first conductors 140, 142 are welded to one another, and second conductors 144, 146 are welded to one another one after the other. Here, the first conductors 140, 142 are twisted with the second conductors 144, 146, as can be seen in FIGS. 5, 7 and 8.

[0053] The welding of the first conductors 140, 142 occurs first. For this purpose, blank ends of the otherwise insulated conductors or cables 140, 142 are introduced into the compression space 121, in order then to shift the lateral slide 113 to the welding width in the above-described manner, in order subsequently to carry out the welding by adjusting anvil 115 and surface plate 119 with sonotrode 114 excited.

[0054] The free blank ends of the second conductors 144, 146 are positioned during the insertion of the blank ends of the first conductors 140, 142 so that they cannot penetrate into the compression space 121.

[0055] After the welding of the first conductors 140, 142 has occurred, that is to say after production of a first connection 148 to be referred to as passage node, the second conductors 144, 146 are introduced into the compression space 121. Here, it must be ensured that the passage node 148 cannot reach the compression space 121.

[0056] This can occur either in that the first and second conductors are untwisted over a longer distance or, on the other hand, according to the teaching of the invention, the passage node 148 is placed or hooked on a retention device which is integrated in the ultrasound welding device 111 and, in particular, within the interior space of the housing 126.

[0057] Thus, untwisting in the immediate vicinity of the passage node 148 is only required to a small extent. Consequently, the effect of the twisting is substantially maintained, namely the mutual influencing of the first conductors 140, 142 with respect to the second conductors 144, 146 and vice versa is prevented, an advantage which is reflected not only in communication technology, but also in the sector of motor vehicle technology.

[0058] In order to fix the passage node 148 so that the welding of the blank ends of the second conductors 144, 146 cannot be interfered with, different possibilities are given, as is explained in reference to the figures.

[0059] A preferred embodiment consists in that the lateral slide 113 acts as retaining device by means of recesses and/or protrusions or other aids. This is explained in reference to FIGS. 3 and 4.

[0060] Thus, according to the embodiment example of FIGS. 3a and 3b, the lateral slide 113 comprises on its upper side 1113 a recess 150, 152 forming an oblique angled triangle in cross section, the short leg of which according to FIG. 3a extends at a distance from the front surface 154 of the lateral slide 113 or facing same (FIG. 3b).

[0061] Irrespective of this, by the depression or recess 150, 152 it is ensured that, during the insertion of the passage node 148, said passage node is fixed during the welding process, The recess or depression 150, 152 extends over the entire width of the lateral slide 113.

[0062] According to the embodiment example of FIG. 3c, a recess 156 of rectangular cross section extending parallel to the front surface 154 is provided as retaining device.

[0063] In FIG. 3d, starting from the upper side 1113 and parallel to the front surface 154, a slot 158 extends, which transitions into a widening 160 which is circular in cross section and which is used as retention device.

[0064] According to the embodiment example of FIG. 3e, starting from the upper side 1113 of the lateral slide 113 is a groove-shaped recess 162 which extends over the entire width of the slide 113 and which, in the embodiment example, has the geometry of a semicircle. An additional possibility for forming a retention device in the lateral slide 113 is given by an undercut 164 (FIG. 3f).

[0065] However, the function of a retention device is also achieved by protrusions 166 or 168 starting from the upper side 1113 (FIG. 4a, b). The protrusion 166, which does not necessarily have to extend over the entire width of the slide 113, has a rectangular geometry in cross section and, according to FIG. 4b, the shape of an L in cross section, so that a free space 170 facing away from the front surface 154 results, into which the passage node 148 can be inserted or hooked.

[0066] However, a retention device can also be formed in the anvil. This is illustrated using FIG. 2. Thus, a protrusion 174 can start from the front surface 172 of the anvil 115, which extends on the slide side, so that, between the front surface 172 and the protrusion 174, a step is formed, on which the passage node 148 can be placed. In order not to influence the welding process, the protrusion 174 transitions flush on the sonotrode side into the lower side 176 of the anvil 115, which in sections delimits the compression space 121.

[0067] In other words, the protrusion 174 is a section of the anvil 115 or of the pressure surface itself. Instead of a protrusion, in the front surface 172, for example, a recess 176 can be provided, into which the first connection or passage node 148 is hooked during the welding of the blank ends of the second conductors 144, 146.

[0068] However, according to FIG. 5, the possibility also exists that a retention device starts from the adjustable housing section 130. In the embodiment example, starting from the housing section 130 are webs or arms 178, 180 which comprise upper sides 182, 184 of hook-shaped design into which the first connection or the passage node 148 is inserted during the welding of the second conductors 144, 146. The arms 180 here extend to the side of the lateral slide 113 and thus to the side of the compression space 121.

[0069] According to the embodiment example of FIGS. 6 to 8, starting from the stationary housing section 128 are hook-shaped protrusions 186, 188 which are used as retention device. The protrusions 186, 188 here have a slight spacing which ensures that the adjustment of the lateral slide 113 cannot be impeded.

[0070] In FIG. 6, the opened housing is represented. In FIG. 7, the welding of the blank ends of the first conductors 140, 142 has already occurred. The produced first connection, that is to say the first passage node 148, is placed on the hook-shaped sections 186, 188, so that the blank ends of the second conductors 144, 146 can then be welded. During the welding itself, the housing 126 is closed, as can be obtained from FIG. 8. Here, a front surface of the adjustable section 130 adjoins a geometrically matched surface of the housing section 128.

[0071] Irrespective of this, in order to be able to lead the first and second conductors 140, 142 or 144, 146 out of the housing 126, the adjustable section 130 in particular has, on the front margin-side, a corresponding yielding material preferably consisting of foam, as can be obtained from FIG. 8.

[0072] Additional embodiments of retention devices can be obtained from FIGS. 9 to 14. These embodiments here relate to the retention devices that start from the housing 126 or the sections 128, 130. Basically, they are designs of the retention devices 178, 180, 182, 184 of the adjustable section 130 or of the retention devices 186, 188 of the stationary section 128.

[0073] In FIGS. 9 and 10, along the hook-shaped upper sides 182, 184, in each case a spring-like element 282, 284 extends, and between them and the upper side 182, 184 of the arm 178, 180, the first connection 148 can be clamped, as can be obtained from FIG. 10.

[0074] According to an embodiment example of FIG. 11, in each case, along each longitudinal side surface of the slide 113, a gripping device comprising in each case two arms 290, 292 or 294, 296 extends, between which a passage node, that is to say, in the embodiment example, the first connection 148, is clamped, in order to then carry out the welding of the second conductors.

[0075] However, retention devices according to the designs of FIGS. 9 to 11 can also start from the stationary section 128 of the housing 126. Thus, spring-like clamping elements 298, 300 are associated with the hook-shaped protrusions 186, 188, and between them and the upper sides of the protrusions 186, 188, a passage node can be clamped, as can be obtained from FIG. 13.

[0076] FIG. 14 provides a gripping device as retention device in accordance with FIG. 11, i.e., in each case a pair of arms 302, 304 and 306 that can be pivoted with respect to one another as well as an additional arm that cannot be seen are adjustable with respect to one another, in order to accommodate a passage node in a clamping manner.

[0077] It should be noted that the method according to the invention can also be carried out when more than two connections are to be welded, that is to say when more than first and second lines are to be welded. Thus, the retention device can consequently be designed so that multiple connections, passage nodes are accommodated. It would be possible to provide more than one retention device for accommodating connections, in order to keep said connections away from the compression space.