Mounting device and method for producing an electrical contact

Abstract

The invention relates to an assembly device for producing an electrical contact (6) between an electronic component (5) and a printed circuit board (8), wherein the electrical contact (6) has at least one contact pin (9') formed on the electronic component (5) which is inserted into a via (11) of the printed circuit board (8), wherein the assembly device has two tool parts (1, 3) that are adjustable relative to each other, the electronic component (5) being held on the first tool part (1) and the printed circuit board (8) being held on the second tool part (3), wherein the two tool parts (1, 3) can be moved towards each other in an insertion stroke, whereby the contact pin (9') can be inserted into the via (11), wherein the assembly device has an alignment unit (16) which performs an alignment process before the insertion stroke.by means of which a tolerance-related positional deviation (Δz) of the contact pin (9') can be aligned with respect to the via (11) in order to ensure a interference contour-free insertion stroke, wherein the alignment unit (16) has at least one funnel element (17) mounted in the second tool part (3) so as to be adjustable in the insertion stroke direction, with a funnel-shaped alignment contour (18) which is formed with a chamfer (20) that terminates at an end-face opening edge region (22), and wherein in the alignment process the funnel element (17) is adjustable from a recessed initial position with an alignment stroke through the via (11) towards the contact pin (9') up to an alignment stroke end (E), characterized in that in the case of a larger positional deviation (Δz) of the contact pin (9') the funnel element (17) with its end-face opening edge region (22) in Alignment stroke until the contact pin head reaches its limit,which interrupts the alignment stroke of the funnel element (17) in an intermediate position (Z), and that upon sensor detection of the interruption of the alignment stroke, the second tool part (3) performs a corrective movement (K) in a plane transverse to the stroke direction, with the aim of threading the contact pin head from the opening edge area (22) into the alignment contour (18) of the funnel element (17).

Description

[0001] The invention relates to an assembly device for producing an electrical contact according to the preamble of claim 1 and to a method for producing such an electrical contact according to the preamble of claim 9.

[0002] The drive unit of an electrically powered vehicle features a pulse-controlled inverter whose components, including a control board and power modules, are mounted on a mounting bracket. The power modules and the control board are connected to each other, for example, via an electrical press-fit connection.

[0003] With such press-fit contacting, the contact pins formed on the power modules are press-fitted into the vias of the control board. In series production, the electrical contacting of the power modules with the control board takes place fully automatically in a generic assembly device. The assembly device has two tool parts with adjustable strokes relative to one another. One of these tool parts carries the power modules and is mounted on the lower, stationary tool part, while the control board is mounted on a cooperating upper, adjustable-stroke tool part. The adjustable-stroke tool part can be moved in a retraction stroke to a bottom dead center, whereby the contact pin can be retracted into the vias of the control board.In order to ensure process-reliable electrical contact, the contact pins must be positioned on the electronic assembly in a complex manner with high positioning accuracy so that the contact pins can be inserted into the corresponding through-holes of the control board with as little interference contours as possible.

[0004] DE 10 2020 212 934 A1 discloses a generic connecting element for electrically connecting two circuit boards. DE 10 2014 117 153 A1 discloses a guide device. JP 2008 - 192 569 A discloses a press-fit contact. DE 10 2016 203 286 A1 discloses a method for mounting a pin header with multiple pins on a printed circuit board. The method comprises the following process steps: aligning the pins according to a predetermined through-hole pattern, securing the aligned pins with a securing device, pushing the aligned free ends through holes in the printed circuit board, and removing the securing device after the through-hole insertion. From DE 10 2012 220 001 A1 an electrical connecting element is known in which the manufacturing effort during assembly is reduced and at the same time an alignment of contact elements with very small tolerance is possible.

[0005] The object of the invention is to provide an assembly device and a method with the aid of which the production of an electrical contact can be carried out more easily in terms of production technology compared to the prior art.

[0006] The object is achieved by the features of claim 1 or 9. Preferred developments of the invention are disclosed in the subclaims.

[0007] The invention is based on an assembly device for establishing electrical contact between an electronic component and a printed circuit board. The electrical contact has at least one contact pin formed on the electronic component, which can be inserted into a hole (i.e. via) or into a through-plating of the printed circuit board. The assembly device consists of two tool parts whose strokes can be adjusted relative to one another, of which the electronic component is held on the first tool part, while the printed circuit board is held on the second tool part. The two tool parts are moved towards one another in an insertion stroke, as a result of which the contact pin inserts into the through-plating. According to the invention, the assembly device has an alignment unit which carries out an alignment process before the insertion stroke, by means of which alignment process a tolerance-related positional deviation of the contact pin with respect to the through-plating can be aligned.In this way, the subsequent retraction stroke can be carried out without any interference contours.

[0008] In one technical implementation, the alignment unit can have at least one funnel element mounted in the second tool part so that its stroke can be adjusted in the retraction stroke direction. The funnel element can comprise a funnel-shaped alignment contour with a circumferential run-on bevel on its side facing the contact pin. The run-on bevel terminates at an end-face opening edge region facing the first tool part. During the alignment process, the funnel element is adjusted from its recessed starting position, in which it is positioned within the second tool part, with an alignment stroke through the via in the direction of the contact pin up to an alignment stroke end. When the contact pin formed on the electronic component is correctly positioned, its head is retracted into the funnel-shaped alignment contour of the funnel element without contact.

[0009] If the contact pin's position is slightly off, its head will come into sliding contact with the bevel of the funnel-shaped alignment contour of the funnel element. In this way, the contact pin head is aligned with the through-hole of the printed circuit board until the end of the alignment stroke is reached.

[0010] If the position of the contact pin is significantly deviated, the following occurs: During the alignment stroke, the funnel element, with its front opening edge area, comes into contact with the contact pin head. This interrupts the alignment stroke of the funnel element in an intermediate position. The interruption of the alignment stroke can be detected by a sensor using an electronic control unit. If the interruption of the alignment stroke is detected by a sensor, the control unit can control one of the two tool parts in a plane transverse to the stroke direction with a particularly circular corrective movement. The corrective movement causes the contact pin head of the contact pin with the deviated position to thread from the opening edge area into the alignment contour of the funnel element. Once threading has been completed, the alignment stroke can be continued from the intermediate position until the end of the alignment stroke.

[0011] In one technical implementation, the stroke of the funnel element can be adjusted by a lifting plunger between its recessed initial length and an alignment stroke end. An overload spring can preferably be supported between the lifting plunger and the funnel element. In this case, the following situation arises with the larger position deviation defined above: Upon reaching the intermediate position, the funnel element is pressed against the contact pin head by the lifting plunger, building up spring force, while the lifting plunger continues to adjust its stroke until its alignment stroke end. The above-mentioned corrective movement then takes place so that the contact pin head of the contact pin with the deviating position is threaded into the funnel-shaped alignment contour of the funnel element. Once threaded in, the funnel element is automatically adjusted until its alignment stroke end, dissipating the spring force generated by the overload spring.

[0012] Sensory detection of the alignment stroke interruption can be accomplished, for example, as follows: The control unit can use position sensors to detect the stroke of the lifting ram and the stroke of the funnel element. The control unit can determine whether or not there is an interruption in the alignment stroke of the funnel element by comparing the stroke of the lifting ram with, for example, the funnel element stroke. If such an interruption in the alignment stroke of the funnel element occurs, the control unit controls one of the two tool parts to perform the above-defined corrective movement transverse to the stroke direction.

[0013] Once the alignment process is complete, a reversing stroke begins, during which the funnel element is retracted from the through-hole into the second tool part, counter to the alignment stroke, back to its starting position. After the reversing stroke has been completed (or superimposed on it), the retracting stroke is performed, during which the two tool parts are moved towards each other to insert the contact pin into the through-hole. In a preferred embodiment, the electrical contact can be a press-fit contact. With this press-fit contact, the contact pin is implemented as a press-fit pin that can be press-fitted into the inner wall of the through-hole. To increase the connection strength, the inner wall of the through-hole can be coated with a metal layer, in particular a zinc layer.

[0014] An embodiment of the invention is described below with reference to the attached figures.

[0015] They show: Fig. 1a to 10 each show different views illustrating the mounting device and the method for producing an electrical contact.

[0016] In the Fig. 1a shows an electrical contact 6 between a power module 5 and a control board 8, produced by means of the assembly device according to the invention. The power module 5 forms a composite together with a cooler 7. The Fig. The assembly indicated in Figure 1 is a component of a pulse-controlled inverter (not shown) of a drive unit of an electrically powered vehicle. The electrical contact 6 between the power module 5 and the control board 8 is implemented as a press-fit contact, in which a plurality of contact pins 9, 9' formed on the power module 5 are press-fitted with through-contacts 11 (i.e., holes or vias) of the control board 8. To increase the connection strength, the inner walls of the through-contacts 11 are coated with a metal layer (not shown) (e.g., a zinc layer). According to the Fig. 1a, the contact pins 9, 9' have a radially expanded central region which is positively and / or materially connected to the respective through-plating 11.

[0017] In the Fig. 1a, of the five contact pins 9, 9', one contact pin 9' is positioned on the power module 5 with a larger tolerance-related positional deviation Δz. The alignment unit 16 of the positionally deviated contact pin 9' enables proper contact 6 with the corresponding through-hole connection 11 despite its positional deviation Δz. It should be emphasized that the positional deviation Δz is exaggerated in the figures. In reality, the positional deviations are a maximum of 0.6 mm from the nominal dimension.

[0018] The alignment unit 16 is part of the Fig. 1b. This is realized as a pressing device and is indicated to the extent necessary for understanding the invention. The pressing device has a stationary lower tool part 1 and a vertically adjustable upper tool part 3. In the Fig. 1b, the pressing device is shown in an open position, in which the two tool parts 1, 3 are spaced apart from each other by a retraction stroke s. Both the upper and lower tool parts 1, 3 have retractable / extendable locating pins 13, which protrude through corresponding positioning openings 15 in the cooler 7 and in the control board 8 during the process. In addition, the upper tool part 3 has a funnel element 17 for each electrical contact 6. Each of the funnel elements 17 is part of an alignment unit 16, by means of which a contact pin, which may be in a different position, can be aligned with the associated through-hole 11. The alignment unit 16 has, in addition to the funnel element 17, a lifting ram 19, which moves the funnel element 17 between a starting position ( Fig. 1b) and a lower alignment stroke end E ( Fig. 4 or Fig. 5) stroke adjusted. According to the Fig. 1b, each of the funnel elements 17 is formed on its side facing the lower tool part 1 with a funnel-shaped alignment contour 18 with a circumferential run-on bevel 20, which terminates at a front opening edge region 22. An overload spring 21 is supported between the lifting ram 19 and the funnel element 17. In addition, each of the funnel elements 17 is assigned a displacement sensor 23, which is in signal connection with a control unit 25. With the aid of the electronic control unit 25, the two tool parts 1, 3, the alignment units 16 and the dowel pins 13 can be controlled. For reasons of clarity, Fig. 1b only the signal connection between the control unit 25 and the Fig. 1b right alignment unit 16 and the signal connection to the locating pins 23 are indicated.

[0019] Below, based on the Fig. 2 to 10 describe an alignment process and a subsequent retraction stroke of the pressing device in a process sequence. By means of the alignment process, the contact pin head of the misaligned contact pin 9' can be aligned with the corresponding via 11.

[0020] In the process sequence, the control board 8 is first positioned vertically one above the other in the correct position in the tool parts 1, 3 via the locating pins 13 ( Fig. 2 and Fig. 3). For example, the control board 8 is pneumatically mounted on the upper tool part 3, while the assembly of power module 5 and cooler 7 is mounted on the lower tool part 1.

[0021] The alignment process then starts. During the alignment process, the funnel elements 17 are moved from their reset initial position with an alignment stroke through the vias 11 in the direction of the contact pins 9 to an alignment stroke end E ( Fig. 4 or Fig. 5) stroke is adjusted. Due to the larger position deviation Δz of the contact pin 9', the associated funnel element 17 cannot be adjusted continuously to its alignment stroke end E, but only to a position in the Fig. 4 shown intermediate position Z. In the intermediate position Z, the front opening edge area 22 of the funnel element 17 is in contact with the contact pin head of the contact pin 9' deviating in position. Upon reaching the intermediate position Z, the funnel element 17 is moved downwards by building up a spring force F ( Fig. 4) is pressed against the contact pin head, while the associated lifting ram 19 is further adjusted to the end of its alignment stroke. Using the displacement sensors 23, the control unit 25 detects that the alignment stroke of one of the funnel elements 17 has been interrupted. In this case, the control unit 25 controls the upper tool part 3 (still located at its top dead center) to perform a circular correction movement K ( Fig. 5). The correction movement K causes the contact pin head of the positionally deviating contact pin 9' to thread from the opening edge area 22 into the alignment contour 18 of the associated funnel element 17. After threading has been completed, the funnel element 17 is automatically adjusted to the alignment stroke end E, reducing the spring force F of the overload spring 21. At the same time, the contact pin head of the positionally deviating contact pin 9' is aligned with the through-hole 11.

[0022] After completion of the alignment process, the upper tool part 3 is moved back to its nominal position ( Fig. 6). The contact pins 9, 9' are then transferred to the control board 8 ( Fig. 7), in which the upper tool part 3 is moved downwards relative to the funnel elements 17 during the retraction stroke, while the funnel elements 17 are retracted upwards into their initial position ( Fig. 8). At the end of the retraction stroke ( Fig. 9), all contact pins 9, 9' are pressed into the associated through-holes 11 of the control board 8. The upper tool part 3 is then moved back to its top dead center ( Fig. 10) and the assembly is removed from the pressing device. List of reference symbols 1, 3 tool parts 5 power modules 7 coolers, 8 Control board 9 contact pin 9' position-deviating contact pin 11 Through-hole plating 13 dowel pins 15 positioning openings 17 Funnel element 6 electrical contact 18 Alignment contour 19 Lifting ram 20 run-on slope 21 Overload spring 22 Opening edge area 23 displacement sensor 25 Control unit Δz position deviation s Retraction stroke E Alignment stroke end K Corrective movement F spring force Z intermediate position

Claims

[1] Assembly device for producing an electrical contact (6) between an electronic component (5) and a printed circuit board (8), wherein the electrical contact (6) has at least one contact pin (9') formed on the electronic component (5) which is inserted into a through-plating (11) of the printed circuit board (8), wherein the assembly device has two tool parts (1, 3) whose strokes are adjustable relative to one another, of which the electronic component (5) is held on the first tool part (1), while the printed circuit board (8) is held on the second tool part (3), wherein the two tool parts (1, 3) are movable towards one another in a retraction stroke, whereby the contact pin (9') can be inserted into the through-plating (11), wherein the assembly device has an alignment unit (16) which carries out an alignment process before the retraction stroke,by means of which a tolerance-related positional deviation (Δz) of the contact pin (9') can be aligned with the through-plating (11) in order to ensure an interference-contour-free insertion stroke, wherein the alignment unit (16) has at least one funnel element (17) which is mounted in the second tool part (3) so as to be adjustable in the insertion stroke direction and has a funnel-shaped alignment contour (18) which is formed with a run-on bevel (20) which terminates at a front-side opening edge region (22), and wherein, during the alignment process, the funnel element (17) can be adjusted in stroke from a recessed starting position with an alignment stroke through the through-plating (11) in the direction of the contact pin (9') to an alignment stroke end (E), , characterized byin that, in the event of a greater positional deviation (Δz) of the contact pin (9'), the funnel element (17) with its front-side opening edge region (22) comes into abutment with the contact pin head during the alignment stroke, as a result of which the alignment stroke of the funnel element (17) is interrupted in an intermediate position (Z), and in that, when the interruption of the alignment stroke is detected by a sensor, the second tool part (3) executes a corrective movement (K) in a plane transverse to the stroke direction, with the aim of threading the contact pin head from the opening edge region (22) into the alignment contour (18) of the funnel element (17). [2] Mounting device according to claim 1, characterized bythat in the event of a minor positional deviation of the contact pin (9'), its head comes into sliding contact with the run-on bevel (20) of the funnel-shaped alignment contour (18) of the funnel element (17) during the alignment stroke, whereby at least the contact pin head can be aligned with the through-plating (11) until the end of the alignment stroke (E) is reached. [3] Mounting device according to claim 1 or 2, characterized by that after threading has been completed, the alignment stroke can be continued from the intermediate position (Z) to the end of the alignment stroke. [4] Mounting device according to one of the preceding claims, characterized bythat the funnel element (17) is stroke-adjustable by a lifting tappet (19) between its starting position and the end of the alignment stroke, and that in particular an overload spring (21) is supported between the lifting tappet (19) and the funnel element (17), so that in particular in the case of a larger position deviation (Δz) when the intermediate position (Z) is reached, the funnel element (17) is pressed against the contact pin head while a spring force (F) is built up, while the lifting tappet (19) is stroke-adjusted up to the end of the alignment stroke, and that after threading has taken place, the funnel element (17) is stroke-adjustable up to the end of the alignment stroke while the spring force (F) is reduced. [5] Mounting device according to claim 4, characterized bythat the assembly device has a control unit (25) for controlling the tool parts (1, 3) and / or the funnel element (17), and that in particular the control unit (25) detects the stroke of the lifting ram (19) and / or the funnel element (17), and that in particular the control unit (25) determines the interruption of the alignment stroke of the funnel element (17) by monitoring the funnel element stroke. [6] Mounting device according to one of the preceding claims, characterized by that after completion of the alignment process, a reversing stroke takes place, during which the funnel element (17) can be retracted from the through-plating (11) into the second tool part (3) in the opposite direction to the alignment stroke. [7] Mounting device according to claim 6, characterized bythat after the reversing stroke, the insertion stroke can be carried out, in which the two tool parts (1, 3) can be moved towards each other in order to insert the aligned contact pin (9') into the through-plating (11). [8] Mounting device according to one of the preceding claims, characterized by that the electrical contact (6) is a press-fit contact, in which the contact pin (9') is realized as a press-fit pin which is press-fitted with the inner wall of the through-contact (11), and that in particular to increase the connection strength the inner wall of the through-contact (11) is coated with a metal layer, in particular a zinc layer. [9] A method for producing an electrical contact (6) between an electronic component (5) and a printed circuit board (8), wherein the electrical contact (6) has at least one contact pin (9') formed on the electronic component (5) which is inserted into a through-plating (11) of the printed circuit board (8), wherein the assembly device has two tool parts (1, 3) whose strokes are adjustable relative to one another, of which the electronic component (5) is held on the first tool part (1), while the printed circuit board (8) is held on the second tool part (3), and wherein the two tool parts (1, 3) are moved towards one another in a retraction stroke, whereby the contact pin (9') is inserted into the through-plating (11), wherein the assembly device has an alignment unit (16) which carries out an alignment process before the retraction stroke,by means of which a tolerance-related positional deviation (Δz) of the contact pin (9') is aligned with the through-plating (11) in order to ensure an interference-contour-free insertion stroke, wherein the alignment unit (16) has at least one funnel element (17) which is mounted in the second tool part (3) so as to be adjustable in the insertion stroke direction and has a funnel-shaped alignment contour (18) which is formed with a run-on bevel (20) which terminates at a front-side opening edge region (22), and wherein in the alignment process the funnel element (17) is adjusted in stroke from a recessed starting position with an alignment stroke through the through-plating (11) in the direction of the contact pin (9') to an alignment stroke end (E), , characterized byin that, in the event of a greater positional deviation (Δz) of the contact pin (9'), the funnel element (17) with its front-side opening edge region (22) comes into abutment with the contact pin head during the alignment stroke, as a result of which the alignment stroke of the funnel element (17) is interrupted in an intermediate position (Z), and in that, when the interruption of the alignment stroke is detected by a sensor, the second tool part (3) executes a corrective movement (K) in a plane transverse to the stroke direction, with the aim of threading the contact pin head from the opening edge region (22) into the alignment contour (18) of the funnel element (17).

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