Conductor arrangement for electrically connecting a first contact element to a second contact element

Abstract

The present invention relates to a conductor arrangement for electrically connecting a first contact element to a second contact element, the conductor arrangement having a first connection area for connection to the first contact element and a second connection area for connection to the second contact element. The first and second connection areas are each arranged at opposite ends of a conductor rail connecting the connection areas and have several elastically deformable, spring-loaded contact tongues, which are designed and arranged such that they clamp the connected contact element with a holding force in an electrically conductive manner.

Description

The present invention relates to a line arrangement for electrically connecting a first contact element to a second contact element, and to a separately excited synchronous machine comprising the line arrangement.The increasing demand for electrically and partially electrically operated machines, especially vehicles, makes efficient production and especially efficient installation of their components with one another increasingly important.One embodiment of an electric machine is, for example, a separately excited synchronous machine (FSM). During operation, the rotor winding is usually supplied with direct current, so that a rotor-side magnetic field is generated which interacts with a stator-side magnetic field. This causes rotation of the rotor.In order to energize the exciter, i.e. the exciter windings of the rotor, current must be supplied to the exciter, for example from the power electronics (LE), in order to generate the rotor-side magnetic field.The power electronics and the electric machine are often manufactured separately from one another and only later contacted with one another or connected to one another by conductive elements. For this purpose, insulated and bent copper or aluminum rails are used, which are also referred to as busbars (or busbars). Busbars are particularly said to be better suited for automated assembly in comparison to conventional flexible cable connections. In robot production lines, the rigid busbars can be installed more easily and with a higher process safety compared to flexible cable connections. Up to now, there is a great diversity of components in the connection of the motor elements to the power electronics and energy storage systems, which cannot be used compatibly across them.In addition, clamping or "crimping" tools have to be used in the conventional line arrangements, such as cables or simple metal rails, which makes blind installation difficult or impossible. At the same time, with the conventional line arrangements, tolerance compensation in the event of structural deviations cannot be ensured.The use of tools for connecting motor parts to, for example, the power electronics or the energy storage systems at the same time increases the required construction or installation space of the electric machine, since space must be left for the tool or tools.In addition, the "crimped" or clamped contact points between, for example, power electronics and the excitation windings of a rotor have an increased susceptibility to frictional corrosion, which can shorten the service life of an electric machine.It is an object of the present invention to provide a line arrangement for a connection between a first and second contact element, which line arrangement at least partially overcomes the disadvantages specified above.This object is achieved by the line arrangement according to claim 1.In a first aspect, the present invention provides a line arrangement for electrically connecting a first contact element to a second contact element, having a first connection region for connection to the first contact element and a second connection region for connection to the second contact element. The first and second connection regions are each arranged at opposite ends of a line rail connecting the connection regions and have a plurality of elastically deformable, resilient contact tongues which are designed and arranged such that they each electrically conductively clamp the connected contact element with a holding force.A line arrangement can be an element that is made of a material that is suitable for conducting electric current, for example in the form of a sheet of copper, gold or aluminum shaped according to the invention. The line arrangement according to the invention can thus be used for electrical connection.The line arrangement according to the invention has a first and second connection region to which contact elements of different types can be connected. The designation as first and second connection regions can be applied variably for the respective connection ends of the line arrangement.A first contact element, which can be electrically connected to the line arrangement according to the invention at a first connection region, can be, for example, a current bolt. A current pin can be designed in the form of a pin which, for example, protrudes from the power electronics of a separately excited synchronous machine and with which the current which originates from the power electronics can be passed on.A second contact element, which can be contacted with the line arrangement according to the invention in a second connection region, is, for example, the end of a flat wire. Flat wires are also used in an exciter or exciter coil or winding. In a separately excited synchronous machine, the exciter winding in the rotor must be energized in order to build up a magnetic field which interacts with the magnetic field of the stator and enables the movement of the machine.The power electronics is a central element of electric drives and ensures, for example, that a continuously variable speed increase is possible by the exciter windings being energized accordingly.As already mentioned further above, the first and second connection regions are each arranged at opposite ends of a line rail connecting the two connection regions. The conductor rail can be made of the same or a different conducting material as the connection areas. The conduit rail may either be straight or angled. A conductor rail according to the invention has a greater length than width and can have a length of between 2-10 cm.The first and second connection region according to the invention, which is respectively located at the opposite end of the line rail, has a plurality of elastically deformable contact tongues. The contact studs can be designed such that they are movable in at least one direction, i.e. resilient or elastically deformable, by selecting a thickness of the material for the contact studs, for example, at which the latter yield from one direction under a compressive force. The contact tongues can establish the primary electrical connection between the connection region and the contact element.The contact tongues according to the invention are designed and arranged in such a way that they clamp the contact element(s) in an electrically conductive manner with a holding force. In this case, the resilient contact tongues can form a frictional connection between the connection regions and the contact elements.The line arrangement according to the invention can ensure blind installation or storage of components of an electric machine. The absence of clamping or "crimping" points can lead to less frictional corrosion in an electric machine. In addition, this results in a reduced installation space for the machine.In a first embodiment of the line arrangement according to the invention, the connection regions are designed as closed eyes. In this embodiment, the contact tabs are disposed on the eyelet periphery defining a terminal area that is less than the eyelet width. As a result, a holding force can be built up by the contact tongues on the eyelet periphery, by means of which the contact element is clamped and thus fixed. The contact tongues formed in this way on the lugs can ensure a first tolerance compensation, for example during the blind assembly of the individual machine parts.In a further embodiment, the first connection region is designed in the form of a round eyelet, on the circumference of which there are formed contact tongues which are arranged in the manner of crowns and which extend, starting from the eyelet edge, in a radially inwardly inclined manner. The angle of inclination of the contact tongues relative to the edge of the eyelet can be designed such that the contact tongues touch each other in the middle of the tongue, or such that the contact tongues do not touch each other, but rather only converge concentrically towards the inside. This can be dependent on the elasticity of the production material of the line arrangement, but also on the size or payload of the machine in which the line arrangement is installed, or of the contact element which is connected to the line arrangement.In a further embodiment, the second connection region is designed in the form of a rectangular eyelet which has contact tongues inclined inwardly on two opposite longitudinal sides. The contact tongues can have a free end running obliquely in order to increase the holding force exerted on the contact element.In a further embodiment of the line arrangement according to the invention, the contact tongues are designed in the manner of fingers and / or as contact tabs bent in a U-shape. The finger-like shaped contact tongues can be formed as insulated free elements which are connected to one another via a lower part and thus receive the contact element. The contact tongues can also be bent in a U-shape as tabs which can protrude into the interior of the above-described eyes.In a further embodiment, a connection region is designed such that the plurality of contact tabs bent in a U-shape are formed in pairs opposite one another on the opposite longitudinal sides of the rectangular eyelet for receiving a second contact element of flat design. In a cross-sectional view, the contact tabs can be bent toward one another in the form of a heart in this embodiment. A plurality of contact tabs can be arranged next to one another on in each case one longitudinal side of the eyelet, wherein the opposite longitudinal side correspondingly has the same number of contact tabs, so that a symmetrical shape is obtained in cross section. By means of this, a flat connection region can be realized, in which a flat contact element can be accommodated in a centered manner.In a further embodiment, a connection region of the line arrangement is designed such that the finger-like contact tongues are formed on the round eyelet for receiving a cylindrical or prismatic contact element. In this case, the finger-like contact tongues can each be round at an inner edge of the eyelet, so that a round or cylindrical contact element can be accommodated. However, the finger-like contact tongues can also be designed such that they can receive a polygonal or prismatically shaped contact element, in that the finger-like contact tongues are each designed to be straight at an inner edge of the eyelet, wherein the inner edge of the eyelet correspondingly has a similar polygonal or prismatic shape to the corresponding contact element.In a further embodiment, the line arrangement is designed such that the second connection region can clamp a flat wire and the first connection region can clamp a bolt. A flat wire can be a flat wire that comes from the coils of an exciter of an electric machine. The flat wire can have a material thickness of up to 0.8 mm, but preferably up to 0.5 mm. The bolt can be a current bolt which comes from the power electronics of an electric machine. The current stud can conduct a current of between 10 and 30 A per mm 2 based on the cross section of the stud and the flat wire, and between 4 and 6 A per mm 2 between the stud, or the flat wire and the busbar according to the invention. Accordingly, the outer diameter of the eyes of the first and second connection region can be dimensioned according to a current intensity of the current to be conducted.In a further embodiment, the line rail connecting the two connection regions has a flattened, in particular rectangular, cross section, such that the line rail is of flexible design in the plug-in direction of the contact elements. The conduit rail may have flat or round side edges. The conductor rail is flexible or spring-mounted in the plug-in direction, i.e. in the connection direction of the contact element, which can be realized by a correspondingly small thickness of the conductor rail.The conductor rail can have a thickness of up to 0.8 mm, but preferably up to 0.5 mm with a length of 2-10 cm. It is advisable to keep the length of the conductor rail as short as possible. The line rail is flexible in the thickness direction in comparison to its longitudinal direction. Accordingly, the line element can be elastically deformed in the axial direction, with respect to a rotor axis of an electric machine, or spring in this direction. At the same time, the line rail is rigid in the radial direction.The resilient contact tongues and the resilient conductor rail allow double tolerance compensation, which facilitates blind installation or storage of the machine components.In a further aspect, the present invention provides a separately excited synchronous machine (FSM) in which an exciter winding is connected to power electronics by a line arrangement according to the invention. The contact tongues according to the invention allow the first connection region to clamp a current pin of the power electronics and the second connection region to clamp a flat wire of a current transmission device interacting in contact or contactless fashion with the exciter winding of a rotor of a separately excited synchronous machine.The current transmission device can be designed in the form of a slip ring transformer or in the form of an inductive transformer.The line arrangements are preferably arranged in parallel and lie in the same plane between the motor and the power electronics. In addition, they can be arranged as close as possible to the axis of rotation. In this exemplary embodiment, two ends of a current transmission device for an exciter winding are connected to two current bolts of power electronics that are located next to one another. This can be sufficient for energizing the coils to generate a magnetic field, which can trigger a uniform rotational movement of the externally excited synchronous machine.The resilient configuration of the connection regions and of the line rail as described above enables blind existence with double tolerance compensation of the exciter device of a motor with the power electronics.Further aspects and features of the present invention will become apparent from the dependent claims, the accompanying drawings and the following description of embodiments.Embodiments of the invention will be described by way of example and with reference to the accompanying drawings. The following are shown: FIG. 1 shows a plan view of a line arrangement according to the invention with a first and second connection region FIG. 2 ashows a cross section of a first connection region in a first embodiment FIG. 2 b shows a cross section of a second connection region in a first embodiment FIG. 2 cshows a cross section of a second connection region in a second embodiment and connected contact element FIG. 3 shows a cross section of a line rail in a first, second and third embodiment FIG. 4 shows a schematic plan view for positioning the line arrangement in an electric machine FIG. 5 shows a schematic side view for positioning the line arrangement in an electric machineFIG. 1 shows a plan view of a line arrangement 10 according to the invention. A first connection region 1 is connected to a second connection region 2 via a conductor rail 3. The first connection region is equipped with contact studs 4a, and the second connection region is equipped with contact studs 4b, respectively. The contact tongues are designed such that they are elastically deformable, i.e. elastic or flexible. The direction of extension of the contact tongues in the first connection region 1 and in the second connection region 2 is illustrated by the double arrows in FIG. 1. Accordingly, the contact tongues 4 aand 4 bare deformable or designed to be elastic at least outwards in such a way that they form an inwardly acting holding force which connects a first and second contact element to the line arrangement in a frictionally locking manner.The simple arrows in FIG. 1 show the connection or plug-in direction in which the line element is installed in an electric machine. The line element is plugged out of the paper plane onto the contact elements to be electrically conductively connected.Furthermore, the simple arrows of the plug-in direction in FIG. 1 also show the possibilities of connecting the respective first and second connection regions 1 and 2 to corresponding contact elements 5 and 6, to which reference is made again later under the description of FIGS. 2 cand 4.FIG. 1 shows a first exemplary embodiment in which the first and second connection regions are each designed as an eyelet. The first connection region 1 is designed in the form of a round eyelet 1 b,and the second contact region 2 is designed in the form of an angular eyelet 2 b. The shape of the lugs is not limited to these embodiments, and the shape of the lugs can be matched to the respective contact element to be connected.The lugs 1b and 2b are provided with the contact studs 4a and 4b. In this embodiment, the contact tabs respectively define first and second inner terminal portions 1a and 2a whose inner periphery is smaller than the periphery of the ears 1b and 2b, thereby generating a holding force and allowing the contact member to be accommodated.FIG. 2 ashows an embodiment of the first contact region 1 in a cross-sectional illustration A-A. The line rail 3 on the left in FIG. 2 ais connected to a first connection region 1, which is designed as a round eyelet 1 b. Crown-like contact tongues 4a are formed on the round eyelet. These can be formed over the entire radial surface of the eyelet, or can only run over an inner edge of the eyelet.The contact tongues in the embodiment of FIG. 2a extend inclined inwardly. Accordingly, each contact tongue defines an angle of inclination at the connection to the eyelet, resulting in an inner connection region 1 awhich has a smaller circumference than the eyelet 1 b, as a result of which a contact element is connected in a holding force and in an electrically conductive manner.FIG. 2 b shows a B-B cross section of a first embodiment of the second connection region 2. The second connection region is designed in the form of a rectangular eyelet 2 b. In this exemplary embodiment, finger-like contact tongues 4 bare depicted on the surface of the eyelet 2 bor on its inner edge, said contact tongues being inclined with respect to one another and defining an inner connection region 2 awhich is smaller than the circumference of the eyelet 2 b.The contact tongues 4 bof the second connection region 2 are configured in pairs and opposite one another on a longitudinal side of the rectangular eyelet 2 b.According to a further exemplary embodiment, the contact tongues 4 bof the second connection region 2 can be designed in the form of contact tabs bent in a U-shape. In this case, the inwardly bent contact tabs are connected at one end to the rectangular eyelet, at least at an inner edge, and the bent contact tabs thus define an inner connection region 2 awhich is smaller than the circumference of the eyelet 2 b.According to a further exemplary embodiment, the plurality of contact tabs arranged opposite one another in pairs and bent in a U-shape are designed as contact tongues 4 bin such a way that they can accommodate a flat contact element 5. FIG. 2 cshows a cross section B-B of a second embodiment of the second connection region 2, wherein a flat contact element 5 is connected.In FIG. 2 c, the second connection region 2 is designed in the form of a rectangular eyelet 2 b. On the inner side of the eyelet, contact tabs bent in a U-shape are attached as contact tongues 4b.The contact tabs are shaped in such a way that a free end bent inward by them defines an inner contact region 2 awhich can be elastically deformed in the direction of the double arrow in FIG. 2 c. Thus, the contact tabs can clamp a flat contact element 5 by an inwardly acting holding force, and electrically connect it.FIGS. 3 a- c show cross sections B-B of possible embodiments of the conductor rail 3. The conductor rail serves for connecting the first connection region 1 to the second connection region 2 and is flexible in the direction of the arrow in FIGS. 3 a- c. The arrow direction corresponds to the connection or plug-in direction in which the line arrangement is attached.In FIG. 3 a, a conductor rail is shown which has an oval cross section; accordingly, the conductor rail has a curved surface in plan view. FIG. 3 bshows a conductor rail which has a rectangular cross section. FIG. 3 cshows a cross section of a conductor rail which, in its plan view, has a straight surface but has a bent shape at its flat ends.FIG. 4 shows a schematic installation of the line arrangement according to the invention in an electric machine in a side view. In this exemplary embodiment, two line arrangements 10 each connect a current bolt 6 of power electronics to a feed line 5 for a current transmission device of an exciter winding of an electric machine.In this exemplary embodiment, a second connection region 2 is plugged onto the ends of a flat wire of an exciter winding as a second contact element 5 in the indicated arrow direction in FIG. 3. The first contact element 6 in the form of a current stud of power electronics is likewise inserted into the first connection region in the direction of the arrow. The exciter winding can thus be connected in an electrically conductive manner to the power electronics, wherein a smaller installation space in the electric machine is made possible.Reference numerals denote reference numerals1 first connection region 1 afirst inner connection region 1 bfirst eyelet 2 second connection region 2 asecond inner connection region 2 bsecond eyelet 3 conductor rail 4 a, 4 bcontact tongues 5 second contact element 6 first contact element 10 conductor arrangement

Claims

A line arrangement (10) for electrically connecting a first contact element (6) to a second contact element (5), comprising: a first connection region (1) for connection to the first contact element (6); and a second connection region (2) for connection to the second contact element (5), wherein the first (1) and second connection region (2) are each arranged at opposite ends of a line rail (3) connecting the connection regions and have a plurality of elastically deformable, resilient contact tongues (4a, 4b) which are designed and arranged in such a way that they each electrically conductively clamp the connected contact element (5, 6) with a holding force.The line arrangement (10) according to claim 1, wherein the connection regions (1, 2) are formed as closed eyes (1b, 2b) and the contact tongues (4a, 4b) are arranged on the eye periphery and define a connection region (1a, 2a) which is smaller than the eye width.The line arrangement (10) according to one of claims 1 and 2, wherein the first connection region (1) comprises a round eyelet, on the circumference of which there are formed contact tongues (4a) arranged in a crown-like manner, which extend, starting from the eyelet edge, in a radially inwardly inclined manner.The line arrangement (10) according to one of the preceding claims, wherein the second connection region (2) comprises a rectangular eyelet which has contact tongues (4b) which are inclined in pairs relative to one another on two opposite longitudinal sides.The line arrangement (10) according to one of the preceding claims, wherein the contact tongues (4a, 4b) are designed in the manner of fingers and / or as contact tabs bent in a U-shape.The line arrangement (10) according to claim 5, wherein the plurality of contact tabs bent in a U-shape are configured to receive a flat contact element in pairs opposite one another on the opposite longitudinal sides of the rectangular eyelet.Line arrangement (10) according to one of the preceding claims, wherein the finger-like contact tongues (4a) are formed on the round eyelet for receiving a cylindrical or prismatic contact element.The line arrangement (10) according to one of the preceding claims, wherein the line rail (3) connecting the two connection regions has a flattened, in particular rectangular, cross section, such that the line rail is of flexible design in the plug-in direction of the contact elements.Externally excited synchronous machine, characterized in that a current transmission device for an exciter winding is connected to power electronics by a line arrangement (10) according to one of Claims 1 to 8.

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