Method for manufacturing a busbar device and busbar assembly

Abstract

Method (600) for manufacturing a busbar device (108), wherein the method (600) comprises the following steps: Providing (602) a carrier unit (204) with an insulating element (208) having an adhesive joint (502), wherein the carrier unit (204) comprises a first busbar (206) which is overmolded by the insulating element (208) or glued into the insulating element (208), and wherein the first busbar (206) has a first connecting section (210) and a first contact section (212) adjacent to the first connecting section (210) with a first contact interface (214) for electrically contacting a first contact (200), wherein the insulating element (208) is arranged on the first connecting section (210); Providing (604) a further busbar (216) which has a further connecting section (218) and a further contact section (220) adjacent to the further connecting section (218) with a further contact interface (222) for electrically contacting a second contact (202), wherein the further busbar (216) has a further adhesive point (400) in the further connecting section (218); Arranging (606) a fixing material between the adhesive point (502) and the further adhesive point (400) to create a material-bonded connection between the support unit (204) and the further busbar (216) that is movable about a flexible bearing point (402); and Welding (616) of the first contact interface (214) to the first contact (200) and of the further contact interface (222) to the second contact (202), wherein the first contact (200) is fixed to the second contact (202).

Description

[0001] The present invention relates to a method for manufacturing a busbar device and to a busbar device.

[0002] E-mobility is becoming increasingly important in the automotive industry, leading to the growing use of electric motors. A stable power supply is essential for the proper functioning of such an electric motor and, consequently, the vehicle itself. Furthermore, electric motors can be used in a wide variety of machines across diverse sectors.

[0003] DE 10 2010 010 815 A1 discloses a busbar plate in which busbars are connected to a base plate by means of an elastomer.

[0004] Against this background, the present invention provides an improved method for manufacturing a busbar system and an improved busbar system according to the main claims. Advantageous embodiments are described in the dependent claims and the following description.

[0005] The approach presented here offers a way to implement a busbar system that is both stabilizing and tolerance-compensating. This can be achieved using a flexible material, such as one with an adhesive backing. Furthermore, one of several busbars can be pre-molded with an insulating material, thus simplifying the connection to another busbar. Simultaneously, the insulating material prevents any mutual electrical interference.

[0006] A method for manufacturing a busbar device is presented, comprising a step of providing a carrier unit with an insulating element having an adhesive joint. The method further comprises a step of providing another busbar having a further connecting section and an adjacent contact section with a further contact interface for electrically contacting a second contact, wherein the further busbar has another adhesive joint in the further connecting section. The method also comprises a step of arranging a fixing material between the adhesive joint and the further adhesive joint to create a material-bonded connection between the carrier unit and the further busbar that is movable about a flexible bearing point.

[0007] The carrier unit comprises a first busbar which is overmolded by the insulating element or glued into the insulating element.

[0008] The busbar system can, for example, be connected to a power converter and additionally or alternatively to a vehicle. To maintain a power supply, it can be advantageous to connect individual components of the busbar system using both material-bonded and, additionally or alternatively, form-fit connections. This can further improve vibration resistance, which can be beneficial for vehicles, for example, as it ensures a reliable power supply. The first and second contacts can be designed as counterparts to the contact interfaces, for example, in the form of contact pins. The busbars can each have, for example, an elongated connecting section, which can be planar.The insulating element can, for example, surround or encase the connecting section of the first busbar, thus advantageously electrically isolating the first busbar from the subsequent busbar. Therefore, the insulating element can advantageously be made of a non-conductive material, such as plastic. Generally speaking, the connecting sections are shaped to join the busbars together. The contact sections, on the other hand, can advantageously be shaped to establish an electrical connection with one of the electrical contacts. The fixing material can, for example, be a flexible adhesive material that can advantageously be applied to the bonding points in a spot manner.

[0009] Due to the flexibility of the fixing material, the additional busbar can advantageously be rotated around a pivot axis in two opposite directions. Axial tolerance compensation is also possible via the flexible bearing point.

[0010] The insulating element can be a plastic body. The carrier unit can therefore be provided as a plastic body, possibly with a busbar (in this case, the first busbar) already overmolded. However, busbars bonded directly into plastic parts can also be used. During the process, the busbars are aligned to a geometric point. One busbar may already be overmolded, or all busbars may be bonded in place. This allows for geometrically precise alignment of busbars, with at least one busbar incorporating tolerance compensation. In general terms, busbars are aligned to a geometric element (carrier body) via bonding.

[0011] The first busbar has a first connecting section and a first contact section adjacent to the first connecting section, with a first contacting interface for electrically contacting a first contact, wherein the insulating element is arranged on the first connecting section.

[0012] According to one embodiment, silicone or a flexible acrylate can be used as a fixing material during the assembly step. The choice of fixing material advantageously allows the support unit and the subsequent busbar to be connected yet flexibly movable. This allows for the compensation of tolerances and, additionally or alternatively, vibrations, thus ensuring a reliable power supply.

[0013] Advantageously, the busbar assembly is complete and ready for installation once the adhesive has cured. Tolerance compensation is provided by the flexibility of the connection technology.

[0014] According to one embodiment, the method comprises a step of welding the first contact interface to the first contact and the second contact interface to the second contact. Welding the contact interfaces, or the contact openings of the busbar assembly, to the electrical contacts advantageously prevents slippage and thus improves both the functionality of the busbar assembly and its vibration resistance.

[0015] Furthermore, in a single assembly step, at least the additional busbar can be mounted to a component element. This component element can be an EMC core into which a busbar unit, for example consisting of the busbars, can be inserted.

[0016] Furthermore, a conductor rail device for a vehicle is presented, wherein the conductor rail device comprises a carrier unit with an insulating element that has an adhesive joint. The conductor rail device also comprises a further conductor rail, which has a further connecting section and a further contact section adjacent to the further connecting section, with a further contact interface for electrically contacting the second contact. The further conductor rail has a further adhesive joint in the further connecting section, wherein a fixing material is arranged between the adhesive joint and the further adhesive joint, which is shaped to create a material-bonded connection between the carrier unit and the further conductor rail that is movable about a flexible bearing point.

[0017] The material-bonded connection between the adhesive point and the other adhesive point can be either point-like or surface-like.

[0018] The busbar system can be used, for example, in conjunction with an electric motor or electric machine, or for other vehicle components. The vehicle itself could be a motor vehicle. The first and second contacts could be electrical contacts that connect to the busbar system. The connecting sections could, for example, be aligned in the same direction, such as being positioned one above the other.

[0019] Advantageously, the busbar assembly can be designed to save space. The contact sections can be configured to establish an electrical connection at each contact interface with an electrical contact. Advantageously, the insulating element can be arranged across a flat surface between the first and subsequent connection sections. Advantageously, the subsequent busbar can rotate around an axis of rotation, which may, for example, run perpendicular to the orientation of the connection sections. Accordingly, the adhesive points can each be arranged on an axis oriented perpendicular to the axis of rotation.

[0020] According to one embodiment, the first busbar has a stepped intermediate section between the first connecting section and the first contact section, designed to connect the first connecting section and the first contact section. Furthermore, the second busbar has a stepped intermediate section between the second connecting section and the second contact section, also designed to connect the second connecting section and the second contact section. The intermediate sections can, for example, be connected to the contact section and the connecting section by rounded corners, resulting in the stepped shape. In the assembled state of the busbar assembly, the two intermediate sections can be arranged opposite each other and thus spaced apart.Advantageously, each busbar can therefore have such an intermediate section to create a height difference between the contact sections and the connecting sections. This advantageously prevents a susceptibility to faults caused, for example, by unintentional electrical contact at a position spaced away from the electrical contacts.

[0021] Furthermore, the additional adhesive point can be located at the end of the additional connecting section facing away from the additional contact section. Positioning the additional adhesive point at the end of the additional connecting section advantageously allows the additional busbar to be rotated more easily.

[0022] For example, greater leverage forces can be applied, making tolerance compensation easier. Furthermore, this can also improve vibration resistance, as contact with electrical contacts, for instance, can be made more stable.

[0023] The insulating element can have a retaining projection for holding the additional busbar. Advantageously, the retaining projection can be designed as a guide rail for the additional busbar. This means that the insulating element can advantageously have a retaining projection on each of two opposing edges along the first connecting section, and the additional busbar can advantageously be arranged between the retaining projections.

[0024] According to one embodiment, the busbar device can have a contact element that may include a first contact and a second contact. The contact element can, for example, be configured as a terminal that can have the two oppositely polarized contacts. The contact element can, for example, be coupled to or be part of an electrical component of the vehicle. For example, the contact element can be part of an electric machine or a power converter.

[0025] Furthermore, the invention relates to an electric axle drive for a motor vehicle comprising at least one electric machine, a transmission unit, an inverter, and a busbar system. The electric axle drive is characterized in that the inverter, also referred to as a current converter, is designed as described.

[0026] The transmission device may include a gearbox for reducing the speed of the electric machine as well as a differential.

[0027] Furthermore, the invention relates to a vehicle with an electric axle drive and / or a power converter and a busbar system. The motor vehicle is characterized in that the electric axle drive and / or the power converter is designed as described.

[0028] The invention is explained in more detail by way of example with reference to the accompanying drawings. These show: Fig. 1 a schematic representation of a vehicle according to an exemplary embodiment; Fig. 2 a schematic representation of a busbar device according to an exemplary embodiment; Fig. 3 a schematic representation of a busbar device according to an exemplary embodiment; Fig. 4 a schematic representation of a busbar device according to an exemplary embodiment; Fig. 5 a schematic representation of a busbar device according to an exemplary embodiment; and Fig. 6 a flowchart of an exemplary embodiment of a method for manufacturing a busbar device.

[0029] In the following description of preferred embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, without repeating these elements.

[0030] Fig. Figure 1 shows a schematic representation of a vehicle 100 according to an exemplary embodiment. The vehicle 100 is, for example, designed as a passenger car and is also referred to as a motor vehicle. The vehicle 100 has an electric axle drive 102, which in turn comprises at least one electric machine 104, a transmission unit 106, a busbar assembly 108, and a power converter 110. The electric machine 104 is also referred to, for example, as a drive unit or an electric motor and is coupled, for example, to the transmission unit 106. The power converter 110 and the electric machine 104 are connected to each other using the busbar assembly 108. This means that the busbar assembly 108 is implemented, for example, as a connection interface.The motor vehicle 100 further comprises a power supply unit 112, which is referred to, for example, as a battery. According to this embodiment, the power converter 110 is connected between the power supply unit 112 and the electric machine 104. The power converter 110 further comprises a capacitor 114 and a plurality of switches 116, for example, six in number, which are used to convert the direct current supplied by the power supply unit 112 into alternating current. Furthermore, according to this embodiment, the power converter 100 comprises a plurality of electrical lines 118 which are connected to the electric machine 104.

[0031] Fig. Figure 2 shows a schematic representation of a busbar device 108 according to an exemplary embodiment. The busbar device 108 is similar, for example, to the one shown in Fig. 1 mentioned in the power rail device 108 and is accordingly feasible for a vehicle such as, for example, in Fig. 1 was described.

[0032] The busbar device 108 is designed to contact a first contact 200 and a second contact 202 fixedly arranged relative to the first contact 200, and has an overall, for example, pincer-like shape. The contacts 200 and 202 are, for example, part of a contact assembly 203. The busbar device 108 has a support unit 204, which includes a first busbar 206 and an insulating element 208. The insulating element 208 has an adhesive joint, which is not shown here due to the perspective of the illustration. The first busbar 206 has a first connecting section 210 and a first contact section 212 adjacent to the first connecting section 210, with a first contact interface 214 for electrically contacting the first contact 200.The busbar assembly 108 further comprises another busbar 216, which has a further connecting section 218 and a further contact section 220 adjacent to the further connecting section 218, with a further contact interface 222 for electrically contacting the second contact 202. This means that the contact interfaces 214, 222 are implemented, for example, as connection points that are coupled or can be coupled to the contacts 200, 202. The contact device 203 is implemented, for example, as part of the busbar assembly 108 or can be implemented. The further busbar 216 also has another adhesive point in the further connecting section 218, which is also not visible here due to the perspective.A fixing material is arranged between the adhesive surfaces, shaped to create a material-bonded connection between the support unit 204 and the further busbar 216, which is movable about a flexible bearing point. According to this embodiment, the connecting sections 210, 218 are arranged one above the other in a resting state, i.e., lying on a common line. The insulating element 208 is arranged at least partially between the connecting sections 210, 218. In contrast, the contact sections 212, 220 are exposed according to this embodiment and only optionally each have a mounting opening 224, 226, which is shaped, for example, to screw the busbars 206, 216 to, for example, a vehicle component not shown here.In this embodiment, the contact interfaces 214, 222 are designed as contact openings, which can be created, for example, by punching or drilling. In this embodiment, the mounting openings 224, 226 are smaller than the contact openings. This means that the mounting openings 224, 226 have a smaller diameter than the contact interfaces 214, 222.

[0033] Optionally, the first busbar 206 has a stepped intermediate section 228 between the first connecting section 210 and the first contact section 212, designed to connect the first connecting section 210 and the first contact section 212. The first intermediate section 228 also has rounded corners. Similarly, the second busbar 216 has a stepped intermediate section 230 between the second connecting section 218 and the second contact section 220, designed to connect the second connecting section 218 and the second contact section 220. The second intermediate section 230 also has rounded corners. The intermediate sections 228 and 230 are shaped such that the contact sections 212 and 220 are each arranged at a different height than the connecting sections 210 and 218.According to this embodiment, the contact sections 212, 220 are arranged on a common plane when the busbar assembly 108 is complete. Optionally, the intermediate sections 228, 230 are arranged opposite each other, for example, parallel to each other.

[0034] According to this embodiment, the insulating element 208 has at least one retaining projection 232 for holding the additional busbar 216. This means that the retaining projection 232 is implemented, for example, as a guide rail for the additional busbar 216. To hold and, for example, secure the support unit 204 and the additional busbar 216 in an operating position, the busbar device 108 optionally has a U-shaped component element 234 that encompasses the connecting sections 210 and 218. According to this embodiment, the component element 234 has at least one opening 236 by means of which the component element 234 is also attached to, or can be attached to, the vehicle component. By way of example only, the component element 234 forms an EMC core into which the busbar unit is inserted.

[0035] The described approach offers advantages over overmolded busbars, which form a fixed assembly, or busbars that are loosely mounted using clips, because tolerances can be kept low, thus eliminating the need for large hole diameters to compensate for these tolerances. This allows for the elimination or at least minimization of a nominal air gap between a hole and a contact pin. Furthermore, it provides both good assembly properties and high resistance to vibration and micro-vibrations at the connection points.

[0036] Against this background, vibration-resistant busbars 206, 216 with tolerance compensation potential, also known as busbars, are described in this embodiment. The aim is to achieve the smallest possible gap between a fixed connection point, described here as contact 200, 202 or pin, and a busbar 206, 216, which is subsequently mounted and requires tolerance compensation. The approach described here also provides vibration-resistant mounting of the assembly, i.e., the busbar device 108. The gap between the pin and the contact interface 214, 222 is kept as small as possible to ensure reliable laser welding. To achieve this, the first busbar 206 is permanently encased in insulating material, while the second busbar 216 is flexibly mounted using a remotely located adhesive point.During assembly, the busbar assembly 108 aligns with the support unit 204, and the other busbar 216 is pressed into its final position. Following the laser welding process, this results in a vibration-resistant connection of the entire busbar assembly 108.

[0037] In principle, various configurations are possible with this design, requiring only minimal tolerance compensation. The number of busbars (206, 216) is not limited. Silicone adhesives, for example, are advantageous for the bonding point. Their relatively low modulus of elasticity and high elongation at break, combined with high temperature resistance, are beneficial. Flexible acrylics are also conceivable.

[0038] Fig. Figure 3 shows a schematic representation of a busbar device 108 according to an exemplary embodiment. The busbar device 108 is similar to the one shown in Fig. 2 described busbar device 108 and is usable in a vehicle such as, for example, in Fig. As described in Figure 1. According to this embodiment, the busbars 206, 216 are shown connected to the contact device 203. For example, the busbars 206, 216 are welded to the contacts 200, 202 and thus connected in a vibration-resistant manner.

[0039] Fig. Figure 4 shows a schematic representation of a busbar system 108 according to an exemplary embodiment. The busbar system 108 shown here is similar to the one described in one of the Fig. The busbar assembly 108 described in sections 2 to 3 is shown in this embodiment without the contact element. However, the position of an adhesive joint of the carrier unit 204 and / or a further adhesive joint 400 is shown only by way of example, since the further adhesive joint 400 is arranged on a side facing the insulating element 208. Due to the flexible bearing point, the further busbar 216 can, for example, rotate in two opposite directions 404. If the further busbar 216 is rotated about the flexible bearing point 402, the further contact section 220 also moves in two opposite directions 406. In this embodiment, the further adhesive joint 400 is optionally arranged at an end of the further connection section 210 facing away from the further contact section 220.

[0040] Fig. Figure 5 shows a schematic representation of a busbar device 108 according to an exemplary embodiment. The busbar device 108 is similar, for example, to the one described in at least one of the Fig. The busbar assembly 108 described in Figures 2 to 4 is shown disassembled in this embodiment. This means that the additional busbar 216 is not arranged on the support unit 204 in this embodiment. However, a directional arrow 500 is shown, illustrating how the support unit 204 and the additional busbar 216 are joined together during manufacturing. Furthermore, the adhesive joint 502 of the support unit 204, which is shown in Figure 2 to 4, is also shown in this embodiment. Fig. The adhesive is applied to the further adhesive point shown in section 4. The fixing material is applied between the area shown in Fig. The adhesive point 400 and the adhesive point 502 shown in the illustration are arranged and form an adhesive point or adhesive surface.

[0041] Fig. Figure 6 shows a flowchart of an embodiment of method 600 for manufacturing a busbar system. Method 600 manufactures a busbar system such as those found, for example, in at least one of the Fig. 2 to 5, and which is used, for example, for a vehicle such as in Fig.Method 600 comprises step 602 of providing a carrier unit with a first busbar having a first connecting section and a first contact section adjacent to the first connecting section, the contact section having a first contact interface for electrically contacting the first contact, and an insulating element arranged on the first connecting section, the insulating element having an adhesive joint. Method 600 further comprises step 604 of providing a further busbar having a further connecting section and a further contact section adjacent to the further connecting section, the further busbar having a further adhesive joint in the further connecting section.In step 606 of the assembly process, a fixing material is placed between the adhesive joint and the next adhesive joint to create a movable, material-bonded connection between the carrier unit and the next busbar. For example, silicone or a flexible acrylate is used as the fixing material.

[0042] Optionally, method 600 includes a step 608 of overmolding the first busbar with an insulating material forming the insulating element to obtain the carrier unit. This means that step 608 of overmolding is performed before steps 602 and 604 of provisioning. Furthermore, method 600 according to this embodiment optionally includes a step 610 of connecting the first contact interface to the first contact, a step 612 of moving the further busbar to position the further contact interface opposite the second contact, and a step 614 of connecting the further contact interface to the second contact.More precisely, in step 610 of connecting, a first contact opening of the first contact interface is connected to the first contact; in step 612 of moving, the further busbar is moved relative to the carrier unit around the flexible bearing point to arrange a further contact opening of the further contact interface relative to the second contact; and in step 614 of connecting, the further contact opening is positively connected to the second contact, for example by using pressure acting on the second busbar.

[0043] According to this embodiment, method 600 additionally optionally includes a step 616 of welding the first contact interface to the first contact and the second contact interface to the second contact, as well as a step 618 of placing a U-shaped component element onto the connection sections. Reference sign 100 vehicles 102 electric axle drive 104 electric machine 106 Gearbox unit 108 busbar device 110 power converters 112 Energy supply facility 114 Capacitor 116 Plural of switches 118 Plural of lines 200 first contact 202 second contact 204 carrier unit 206 first busbar 208 Insulating element 210 first connecting section 212 first contact section 214 first contact interface 216 additional power rails 218 further connecting section 220 further contact section 222 additional contact interfaces 224 Mounting opening 226 Mounting opening 228 first intermediate section 230 further intermediate section 232 Holding lead 234 Component element 236 Safety opening 400 more adhesive points 402 flexible bearing point 404 Direction of rotation 406 direction 500 Directional arrow 502 Adhesive point 600 Methods for manufacturing a busbar device Step 602 of providing a carrier unit Step 604 of providing another power rail Step 606 of the arranging process Step 608 of the overmolding process Step 610 of connecting the first contact interface 612 Step of Moving Step 614 of connecting the next contact interface 616th step of welding Step 618 of the setup

Claims

[1] A method (600) for manufacturing a busbar device (108), the method (600) comprising the following steps: Providing (602) a carrier unit (204) with an insulating element (208) having an adhesive point (502), wherein the carrier unit (204) comprises a first busbar (206) which is overmolded by the insulating element (208) or is adhesively bonded into the insulating element (208), and wherein the first busbar (206) has a first connecting section (210) and a first contact section (212) adjacent to the first connecting section (210) with a first contacting interface (214) for electrically contacting a first contact (200), wherein the insulating element (208) is arranged on the first connecting section (210); Providing (604) a further busbar (216) which has a further connecting section (218) and a further contact section (220) adjacent to the further connecting section (218) with a further contacting interface (222) for electrically contacting a second contact (202), wherein the further busbar (216) has a further adhesive point (400) in the further connecting section (218); Arranging (606) a fixing material between the adhesive point (502) and the further adhesive point (400) in order to produce a materially bonded connection between the carrier unit (204) and the further busbar (216) that is movable around a flexible bearing point (402); and Welding (616) the first contacting interface (214) to the first contact (200) and the further contacting interface (222) to the second contact (202), wherein the first contact (200) is arranged fixedly to the second contact (202). [2] The method (600) of claim 1, wherein the insulating element (208) is a plastic body. [3] Method (600) according to one of the preceding claims, wherein in the step (606) of arranging, silicone or a flexible acrylate is used as the fixing material. [4] Method (600) according to one of the preceding claims, comprising a step (618) of mounting at least the further busbar (216) on a component element (234). [5] Busbar device (108) for a vehicle (100), the busbar device (108) having the following features: a carrier unit (204) with an insulating element (208) having an adhesive point (502), wherein the carrier unit (204) comprises a first busbar (206) which is overmolded by the insulating element (208) or is glued into the insulating element (208), wherein the first busbar (206) has a first connecting section (210) and a first contact section (212) adjacent to the first connecting section (210) with a first contacting interface (214) for electrically contacting a first contact (200), wherein the insulating element (208) is arranged on the first connecting section (210), and wherein the first busbar (206) has a step-like first intermediate section (228) between the first connecting section (210) and the first contact section (212), which is designed to connect the first connecting portion (210) and the first contact portion (212) to each other; and a further busbar (216) having a further connecting section (218) and a further contact section (220) adjacent to the further connecting section (218) with a further contacting interface (222) for electrically contacting a second contact (202), wherein the further busbar (216) has a step-like further intermediate section (230) between the further connecting section (218) and the further contact section (220), which is designed to connect the further connecting section (218) and the further contact section (220) to one another, and wherein the further busbar (216) has a further adhesive point (400) in the further connecting section (218), wherein a fixing material is arranged between the adhesive point (502) and the further adhesive point (400), which fixing material is shaped to produce a material-to-material connection between the carrier unit (204) and the further busbar (216), which is movable about a flexible bearing point. [6] Busbar device (108) according to claim 5, wherein the material connection between the adhesive point (502) and the further adhesive point (400) is point-shaped or planar. [7] Busbar device (108) according to one of claims 5 to 6, wherein the insulating element (208) has a holding projection (232) for holding the further busbar (216). [8] Busbar device (108) according to one of claims 5 to 7, comprising a contact device (203) comprising the first contact (200) and the second contact (202). [9] Electronic circuitry in a motor vehicle with at least one electric drive and a busbar device (108) according to one of claims 5 to 8. [10] Electric axle drive (102) for a vehicle (100) with at least one electric machine (104), a transmission device (106) and a power converter (110) and a busbar device (108) according to one of claims 5 to 8, wherein the power converter (110) and the electric machine (104) are connected to one another using the busbar device (108). [11] Vehicle (100) comprising an electric axle drive (102) according to claim 10 and / or a power converter (110) with a busbar device (108) according to one of claims 5 to 8 and / or a busbar device (108) according to one of claims 5 to 8.

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