DE102017205970A1 - Detachable electrical connection of power electronics with an e-machine - Google Patents

Abstract

The invention relates to a connecting device (1) for releasably electrically conductive connection of power electronics (2) for operating an electric motor (3) with an electrical winding (4) of the electric motor (3), with a connecting conductor (6) a first electrically conductive connection point (9A) is provided between a connection (6) of the power electronics (2) and the connection conductor (6), and a second electrically conductive connection point (9B) is arranged between the connection conductor (9) and the winding (4) is provided, and wherein one of the first and second connection point (9A, 9B) insoluble and the other of the first and second connection point (9A, 9B) is made detachable. The invention also relates to a manufacturing method for such a connection device (1) and a drive unit (5) with such a connection device (1) and a vehicle drive system with such a drive unit (5).

Description

The invention relates to a connecting device for releasably electrically conductive connection of power electronics for operating an electric motor with an electrical winding of an electric motor. It also relates to methods of making such a connection device. It also relates to a drive unit with an electric motor, with power electronics and with such a connection device. It also relates to a vehicle drive system having such a drive unit.

To operate an e-machine, it may be necessary to carry very high electrical currents from the power electronics to the e-machine, for example when using an e-machine as a traction drive in a vehicle drive system. In addition, such use requires the electrical connection to be resistant to vibration and, moreover, to be relatively easily detachable in order to be able to disconnect the electric machine from the power electronics (for example for replacement / repair). In addition, the number of joints should be kept small in order to minimize the number of possible sources of error and weight.

In the not pre-published DE 10 2016 208 291 A1 the applicant is proposed a spring clip for the mechanical and electrical connection of contact partners. These are in principle suitable for such a connection device.

The object of the present invention is to improve the state of the art.

This object is achieved by the objects specified in the main claims. Preferred embodiments thereof are the dependent claims.

Accordingly, a connecting device is proposed for releasably electrically conductive connection of power electronics, which serves for operating an electric motor, with an electrical winding of an electric motor.

The proposed connection device has a connection conductor. It also has a first electrically conductive connection point between a connection of the power electronics and the connection conductor. In addition, it has a second electrically conductive connection point between the connection conductor and the winding. One of the first and second connection point is designed to be insoluble. In contrast, the other of the first and second connection point is made detachable.

There are between the connection of the power electronics and the winding of the electric motor by the proposed connection device so in particular exactly two connection points, namely said first and second connection point. One of the two is detachable, and the other of the two is carried out insoluble. In the production of the connecting device, the releasable connection point is preferably produced first and then only the permanent connection point.

In principle, the connecting device can have a plurality of such connecting conductors. Each of the connecting conductors thereby connects one of a plurality of terminals of the power electronics with one of a plurality of windings of the electric motor detachably and electrically. For this purpose, a correspondingly executed first and second connection point is provided at each connection conductor.

An inextricably executed joint is separable in particular only with a destruction of the actual connection point forming or generating connecting means. Insoluble therefore does not mean that the connection point would basically no longer be separable. An insoluble joint can be produced, for example, by cohesive bonding, such as by welding or soldering or pressure welding, and / or by plastic deformation, such as by crimping or riveting.

In contrast, a detachably executed connection point can be separated in particular without destroying the connecting means forming or generating the actual connection point. A detachable connection point can be produced, for example, by means of screws or a plug-in contact or by means of releasable clamps or detachable clips. After the separation of the junction so the respective connection means, such as the screw, clamp, the clips or the plug / socket, etc., remains largely preserved and can optionally be reused.

The detachable executed connection point is presently preferred by means of one of in the DE 10 2016 208 291 A1 produced spring clips.

Under an electric motor is particularly understood a machine that converts electrical energy (electrical current, electrical voltage) into mechanical energy (speed, torque on a shaft) or vice versa. This may thus be in particular an electric motor or a correspondingly executed generator. The electric motor can in particular be an induction machine, such as an asynchronous or Synchronous machine. Alternatively, it may be a DC machine.

Such an electric machine has at least one, in particular several, windings. These windings may be provided in a stator and / or rotor of the electric motor. The winding serves for the said conversion of the electrical energy into mechanical energy or vice versa. The winding may for example be formed by a single electrical conductor of conductive solid material or by a strand (wire bundle) with a plurality of electrical conductors. The connecting device is used in particular for the electrical connection of the power electronics with a winding end, ie with a free end of the winding. The winding end is located in particular on a winding head of the electric motor.

Under a power electronics for operating the electric motor is particularly to understand electronics that has appropriate electrical components with which they can provide electrical energy to operate the electric motor available (engine operation) and / or with which they electrical energy from can dissipate the electric motor (generator operation). The power electronics preferably have electrical power semiconductor switches, such as, for example, MOSFETs or IGBTs.

The power electronics are preferably an inverter or at least part of an inverter. An inverter is designed to convert a direct electrical current into an alternating electrical current or vice versa. Such an inverter is therefore also called AC / DC converter. Alternatively, the power electronics may also be a converter or at least part of an inverter. Such a converter is designed to convert an alternating electrical current with one frequency into an alternating electrical current with a different frequency or vice versa. Such an inverter is therefore also called AC / AC converter.

However, the power electronics can also have such an inverter and such a converter, for example, united in a power electronics module.

The connecting conductor is preferably an electrical conductor with a low electrical resistance. For this purpose, the connecting conductor consists in particular of copper or aluminum (this includes corresponding Cu or Al alloys). Preferably, the connection conductor is formed by a single electrical conductor made of solid material. The connection conductor thus forms in particular a busbar, also called bus bar. The connection conductor has a suitable shape in order to serve as a connection between the winding and the associated connection of the power electronics. An L-shaped connection conductor has proven to be particularly suitable. Here, one leg of the L-shape may be shorter than the other leg of the L-shape.

In the proposed connection device, the number of necessary connection points is low. In addition, only one of the connection points needs to be detachable. This can be a significant savings in space, weight and cost can be achieved. In addition, this is the mechanical stress on the joints and the current-carrying components, which is caused by manufacturing tolerances and the thermal expansion differences, low. Thus, damage to the joints or components involved, such as loosening or breakage, can be prevented within the operating life. In addition, elaborate and risky manufacturing steps, such as a positioning of a cable lug of the winding of the electric motors, can be saved.

In addition, no separate opening in the housing of the power electronics for a tool (for example, a screwdriver or a pair of pliers) for opening or closing the detachable connection point mandatory, since the detachable connection point may be located in the housing of the electric motor and not in the housing the power electronics. Therefore, an existing in the housing of the electric motors opening can be used.

Preferably, two ends or the two ends of the connecting conductor are designed for the production of the connection point. The two connection points are thus in the range of ends of the connection conductor. Accordingly, one end is made to make the first joint while the other end is made to make the second joint.

Preferably, one of the ends of the connecting conductor is designed as an eyelet for producing the second connecting points. In this eye, the winding of the electric motor, in particular the coil end, are introduced. Subsequently, the eyelet with the winding cohesively and / or positively connected electrically conductive, for example by pressure welding or soldering or welding or crimping to form the permanent second connection point. The other end of the connection conductor is then designed to establish the first connection point. For this purpose, this other end can be designed with a receptacle for corresponding connection means.

By such an eyelet on the connection conductor, the winding of the electric machine need only be introduced therein in preparation for the preparation of the second connection point. An often provided with winding ends extra cable lug or sleeve is therefore not needed.

In a preferred embodiment of the connecting device so the first connection point is made detachable, while the second connection point is carried out insoluble. The (first) connection point between the connection of the power electronics and the connection conductor is therefore detachable and the (second) connection point between the connection conductor and the winding is therefore insoluble.

The power electronics preferably form an own module. For this purpose, the power electronics can be arranged in a separate housing, that is to say a power electronics housing. The housing may be completely closed or it may be open at least in the direction of the electric motor. In the latter case, the housing is designed in particular trough-shaped.

The electric machine also preferably forms an own module. For this purpose, the electric motor can be arranged in a separate housing, that is to say a power electronics housing. The housing may be completely closed, with the exception of some required openings (such as for a drive shaft of the electric motor, as well as for the connections of the power electronics and / or for supplying and removing a coolant), or at least in the direction of the power electronics to be open.

The two modules "power electronics" and "e-machine" are in particular each designed so that they can be joined together to form a common drive unit.

In a preferred embodiment of the connecting device, the power electronics are arranged in a separate housing, and the electric motor is arranged in a separate housing. The connection of the power electronics in this case protrudes from the housing of the power electronics and through a (first) opening of the housing of the e-machines in the housing of the e-machines inside. This (first) opening in the housing of the electric motor can serve in particular exclusively for the electrical connection of the power electronics to the electric motor. It can therefore be dimensioned accordingly small. The first and second connection points are arranged inside the housing of the electric motor. As a result, all connection points in which the connection conductor is involved are located within the e-machine housing. The preparation of the joints can then be done by a (other, second) opening of the E-machine housing, for example by an open end of the electric motor, which is later closed with a housing cover or a bearing plate for mounting a drive shaft of the electric motor.

Preferably, the (first) opening of the housing of the electric machines, through which the connection of the power electronics is led, a seal. Through this seal then the connection of the power electronics is performed. The seal consists for example of an elastomer. In particular, this seal prevents particles from the electric machine from entering the power electronics. So it serves as a bulkhead seal between electric motor and power electronics.

Preferably, the connecting device also has at least one signal line between the electric motor and the power electronics, which likewise leads through the (first) opening of the housing of the electric motors and optionally through the seal. Such a signal line is used in particular for transmitting information for operating the electric motor. In particular, these may be signals from a speed sensor of the electric motor and / or a temperature sensor or other sensors. However, these can also be signals of a higher-level power electronics control unit. The signal line may be embedded in the seal.

In a preferred development of the connection device, the connection of the power electronics has a (own) fixed plastic housing. This plastic housing may be formed, for example, by overmolding the connection with plastic. Preferably, this plastic housing is attached to a circuit board or a power module of the power electronics and / or to the housing of the power electronics. This may be a detachable or non-detachable attachment. The plastic housing can therefore be screwed, clipped, glued, riveted, plugged etc., for example.

In a preferred development of the connecting device, the connecting conductor has a (separate) solid plastic housing. This plastic housing may be formed, for example, by an encapsulation of the connecting conductor with plastic. Preferably, this plastic housing is attached to the housing of the electric motor. Again, it may be a detachable or non-detachable attachment. The plastic housing can therefore be screwed, clipped, glued, riveted, plugged etc., for example. In particular, this is another Plastic housing as that of the connection of the power electronics.

In a preferred embodiment of the connecting device, the electric motor has a plurality of windings. This is the case, for example, when the electric motor is a preferred multiphase induction machine, such as a three-phase electric motor or a six-phase electric motor. The power electronics then has a corresponding plurality of terminals. In this case, a corresponding plurality of connecting conductors is provided, each of which (exactly) electrically connects one of the windings with (exactly) one of the terminals of the power electronics. Thus, each of the windings is electrically contacted via the associated connection conductor with the associated connection of the power electronics.

Preferably, a common solid plastic housing is then provided for this plurality of terminals of the power electronics. As explained above, this can be formed by encapsulation of the connections with plastic. It is accordingly attached to a printed circuit board or to a power module of the power electronics and / or to the housing of the power electronics. Alternatively or additionally, then also have the plurality of connecting conductors have a common solid plastic housing. As explained above, this can also be formed by encapsulation of the connecting conductors with plastic. This is accordingly attached to the housing of the electric motor.

The connections of the power electronics are preferably of different lengths. In contrast, then the connection conductors are the same length. In particular, the connection conductors can be identical. The connections can thereby be adapted to a contour of the electric motor. Several identical connection conductors may be provided in the common solid plastic housing.

A method of manufacturing the connection device is also proposed. The method provides that first the first connection point is made, ie in particular the detachable connection point. Later, in particular immediately thereafter, the second connection point is produced, that is to say in particular the permanent connection point.

• • Der Verbindungsleiter wird in einem Gehäuse der E-Maschine angeordnet.
• • Der Verbindungsleiter wird in den Bereich der Wicklung gebracht. Insbesondere wird ein Ende des Verbindungsleiters in den Bereich eines Wicklungsendes gebracht. Dies kann gleichzeitig mit dem obigen Schritt erfolgen. Alternativ dazu wird die Wicklung in den Bereich Verbindungsleiters gebracht. Wenn der Verbindungsleiter über die Öse an einem seiner Enden verfügt, wird in diesem Schritt die Wicklung beziehungsweise das Wicklungsende in diese Öse lose eingeführt.
• • Ein Leistungselektronikmodul mit der Leistungselektronik wird an die E-Maschine angeordnet.
• • Der Anschluss der Leistungselektronik wird in den Bereich des Verbindungsleiters gebracht, insbesondere in den Bereich des anderen Endes des Verbindungsleiters. Dies kann gleichzeitig mit dem obigen Schritt „Anordnen der Leistungselektronik wird an die E-Maschine“ erfolgen. Es befinden sich nun alle Elemente der Verbindungsvorrichtung in der richtigen Position, um die Verbindungsstellen herstellen zu können.
• • Dementsprechend wird die (bevorzugt lösbare) erste Verbindungsstelle zwischen dem Anschluss der Leistungselektronik und dem Verbindungsleiter hergestellt.
• • Anschließend wird zunächst die (bevorzugt unlösbare) zweite Verbindungsstelle zwischen dem Verbindungsleiter und der Wicklung hergestellt.

Preferably, the manufacturing process is as follows:

• • The connection conductor is placed in a housing of the electric motor.
• • The connection conductor is brought into the area of the winding. In particular, one end of the connection conductor is brought into the region of a winding end. This can be done simultaneously with the above step. Alternatively, the winding is brought into the area connecting conductor. If the connecting conductor has the eyelet at one of its ends, the winding or the winding end is loosely inserted into this eyelet in this step.
• • A power electronics module with the power electronics is placed on the electric motor.
• • The connection of the power electronics is brought into the area of the connection conductor, in particular into the area of the other end of the connection conductor. This can be done simultaneously with the above step "arranging the power electronics to the electric machine". There are now all the elements of the connecting device in the correct position to make the joints can.
• Accordingly, the (preferably detachable) first connection point is established between the connection of the power electronics and the connection conductor.
• Subsequently, the (preferably insoluble) second connection point between the connection conductor and the winding is first produced.

The proposed manufacturing method applies correspondingly for the case when the connecting device has a plurality of connections of the power electronics with a plurality of windings of the electric machine via a plurality of connecting conductors for detachable electrical connection. Then, first all (preferably detachable) first connection point are prepared and then all (preferably insoluble) second connection point.

Furthermore, a drive unit with an e-machine and with power electronics for operating the e-machine is proposed. The drive unit has the proposed connection device for detachable, electrically conductive connection of the power electronics with at least one electrical winding of the electric motor.

Furthermore, a vehicle drive system with such a drive unit is proposed. The electric motor is designed as a traction drive. The electric motor is thus primarily for generating the vehicle propulsion required Torque provided. As a secondary function can be provided, for example, that the electric motor for energy recovery can be used as a generator.

• 1a-c eine Verbindungsvorrichtung und einen Ablauf zu deren Herstellung,
• 2 eine Antriebseinheit,
• 3 eine Leistungselektronik für die Antriebseinheit nach 2,
• 4 eine Antriebseinheit,
• 5 eine Leistungselektronik für die Antriebseinheit nach 4,
• 6a-d eine Verbindungsvorrichtung und einen Ablauf zu deren Herstellung,
• 7a-d eine Verbindungsvorrichtung und einen Ablauf zu deren Herstellung,
• 8 eine Verbindungsvorrichtung,
• 9 eine Verbindungsvorrichtung,
• 10 eine Verbindungsvorrichtung.

In the following the invention will be explained in more detail with reference to figures, from which further preferred embodiments and features of the invention can be removed. Shown schematically in each case:

• 1a-c a connecting device and a process for its production,
• 2 a drive unit,
• 3 a power electronics for the drive unit after 2 .
• 4 a drive unit,
• 5 a power electronics for the drive unit after 4 .
• 6a-d a connecting device and a process for its production,
• 7a-d a connecting device and a process for its production,
• 8th a connection device,
• 9 a connection device,
• 10 a connection device.

In the figures, identical or at least functionally identical components / elements are provided with the same reference numerals.

1a-c show a connecting device 1 and a preferred procedure for their preparation.

The connection device 1 serves for releasable, electrically conductive connection of power electronics 2 to operate an electric machine 3 with an electrical winding 4 the electric machine 3 , Together form the electric motor 3 and the power electronics 2 a drive unit 5 (please refer 1c ).

The power electronics 2 , which is preferably an inverter, has at least one connection 6 that with the winding 4 the electric machine 3 by means of the connecting device 1 to be contacted electrically. About the connection device 1 So should an electric current to operate the electric motor 3 , which is preferably a multi-phase induction machine, be feasible. For every phase or winding 4 the electric machine 3 can such a connection 6 at the power electronics 2 be provided.

The power electronics 2 and the electric machine 3 each form a module with its own housing. The housing of the power electronics 2 is to the housing of the electric motor 3 attachable to the drive unit 5 to build. The housing of the line electronics 2 is on one in the direction of the electric motor 3 pointing side open. Thus, the housing is trough-shaped. The connection 6 protrudes from this open side of the housing.

The connection 6 is with electrical components of power electronics 2 electrically connected to the electrical power supply of the electric motor 3 serve, in particular one or more semiconductor switches, capacitors, etc. The connection 6 can from a circuit board 7 or a power module of the power electronics 2 stand out and attached to it. Alternatively or additionally, the connection 6 on the housing of the power electronics 2 attached. The connection 6 preferably has a plastic housing. At the connection 6 in particular, it is a so-called busbar, that is, a solid electrical conductor made of solid electrically conductive material, such as copper or aluminum. The conclusion 6 is exemplified tongue-shaped.

For the preparation of the connecting device 1 and the drive unit 5 First, the module of power electronics 2 and the module of the electric motor 3 provided ( 1a ). Inside the housing of the electric motor 3 was already in advance an electrically conductive connection conductor 9 arranged. At the connection conductor 9 it is also preferably a busbar. As shown, the connection conductor 9 be designed for example L-shaped. In principle, however, he could also be shaped differently. The connection conductor 9 preferably has its own plastic housing. So he can in the housing of the electric motor 3 be attached.

At one end is the connection conductor 9 for producing a first electrically conductive connection point 9A with the connection 6 executed. At the opposite other end is the connection conductor 9 for producing a second electrically conductive connection point 9B with the winding 4 executed. Here is the connection conductor 9 preferably designed as an eyelet. In the eyelet is then a free winding end of the winding 4 introduced. This end of the coil does not require an extra cable lug or sleeve for this purpose. For example, this is the end of a winding designed as enamel wire bundle 4 ,

After the provision of the power electronics modules 2 and the electric machine 3 they are put together ( 1b ) and fastened together, for example screwed. At the Joining will be the connection 6 the power electronics 2 through an opening provided for this purpose 8th in the housing of the electric motor 3 guided. The opening 8th may have a seal for bulkhead sealing, through which the connection 6 to be led. Through the opening 8th It is also possible to carry one or more signal lines which are used to transmit information between the e-machine 3 and power electronics 2 serve, such as sensor signals and / or control signals.

A connection area of the connection 6 for the production of the first connection point 9A with the connection conductor 9 is located inside the housing of the e-machine after assembly 3 in the region of the respective end of the connection conductor 9 ,

Connecting will be the first connection point 9A produced. This can be a suitable tool 10 through another opening 11 the housing of the electric motor 3 to the respective end of the connection conductor 9 be guided. This first junction 9A is carried out releasably in the present case. Thus, the first connection point 9A be subsequently separated again without the used connecting means, such as screws, clamps, etc., are substantially destroyed. The first connection point 9A in particular by a screw connection 6 and connecting conductors 9 or generated by a clamp with a spring clip. However, there are also other releasable connection types used, such as a connector. The tool 10 can then be removed from the housing of the electric motor 3 be removed.

After the first junction 8th can also be the second connection point 9B getting produced ( 1c ). This is a corresponding additional tool 12 through the opening 11 the housing of the electric motor 3 to the respective end of the connection conductor 9 guided. This second connection point 9B is executed insoluble here. Thus, the second connection point 9B can not subsequently be separated again without the used connecting means, such as welding or crimping material, etc., are substantially destroyed. The second connection point 9B is in particular by a pressure welding of connecting conductor 9 and winding 4 generated. This is the eyelet of the connection conductor 9 with the winding end of the winding inserted therein 4 plastically deformed and heated at the same time, so that a positive and cohesive connection between connecting conductors 9 and winding 4 arises. One possibly on the winding 4 located paint layer is burned and / or broken up. However, there are also other insoluble connection types used, such as crimping, soldering or pure welding.

If the electric machine 3 over several windings 4 or phases, this procedure can be applied to all windings 4 or phases may be provided. Thus, for every windings 4 or phases exactly one connection conductor 9 provided and a corresponding connection 6 the power electronics 2 , In this case, preferably all first, detachable connection points are preferred first 9A created and then only all second, permanent joints 9B ,

In this way, a connection device 1 created, which a first electrically conductive and detachable connection point 9A between a connection 6 a power electronics 2 and a connection conductor 9 and which a second electrically conductive and permanent joint 9B between the connection conductor 9 and a winding of an electric machine 3 having.

• • In einem ersten Schritt wird der Verbindungsleiter 9 in dem Gehäuse der E-Maschine 3 angeordnet.
• • Gleichzeitig oder danach wird in einem zweiten Schritt der Verbindungsleiter 9 in den Bereich der Wicklung 4 gebracht wird, oder umgekehrt wird die Wicklung 4 in den Bereich des Verbindungsleiters 9 gebracht. Hierbei wird beispielsweise das Wicklungsende in die Öse (sofern vorhanden) des Verbindungsleiters 9 geführt.
• • In einem anschließenden dritten Schritt wird die Leistungselektronik 2 an die E-Maschine 3 angeordnet.
• • Hierbei wird der Anschluss 6 der Leistungselektronik 2 in den Bereich des Verbindungsleiters 6 gebracht.
• • In einem anschließenden vierten Schritt wird die erste lösbare Verbindungsstelle 9A zwischen dem Anschluss 6 der Leistungselektronik 2 und dem Verbindungsleiter 9 hergestellt.
• • In einem anschließenden fünften Schritt wird die zweite unlösbare Verbindungsstelle 9B zwischen dem Verbindungsleiter 9 und der Wicklung 4 hergestellt.

The procedure according to 1a-c can also be described as follows:

• • In a first step, the connecting conductor 9 in the housing of the electric motor 3 arranged.
• • At the same time or after that, in a second step, the connection conductor 9 in the area of the winding 4 is brought, or vice versa, the winding 4 in the area of the connection conductor 9 brought. In this case, for example, the winding end in the eyelet (if present) of the connecting conductor 9 guided.
• • In a subsequent third step, the power electronics 2 to the electric machine 3 arranged.
• • This will be the connection 6 the power electronics 2 in the area of the connection conductor 6 brought.
• • In a subsequent fourth step, the first detachable connection point 9A between the connection 6 the power electronics 2 and the connection conductor 9 produced.
• • In a subsequent fifth step, the second permanent connection becomes 9B between the connection conductor 9 and the winding 4 produced.

This solution has the following advantages:

By doing that, the winding 4 Only in the last step exactly with the connection conductor 9 is permanently connected, the burden on the relevant joints and components is kept very low and reproducible. This is one higher Safety and life of the high current connection against loosening or breakage achievable, since these during operation of the drive unit 5 is exposed to further stresses due to vibration and temperature differences. Manufacturing-related pre-damage of joints 9A . 9B or painted windings 4 will be avoided. Due to the smaller number of joints and conductor components space, weight and cost can be saved. An elaborate and risky manufacturing step, a special shaping of the winding ends of the windings 4 For example, with a stencil tool is thus avoided. A separate housing opening in the housing of the power electronics 2 for the preparation of the joints 9A . 9B not necessary. At the case opening 11 it can be an opening that is anyway structurally required. This can later, for example by a bearing plate or a housing cover of the electric motor 3 to be closed.

2 and 4 show each in isometric views preferred drive units 5 each with an electric motor 3 and each with a power electronics 2 for operating the electric machine 3 , For clarity, only the upper half of the electric motor 3 shown. Such drive units 5 are preferably used in a vehicle drive system in which the electric motor 3 serves as a traction drive.

For electrical contacting of the connections 6 the power electronics 2 with the windings 4 the electric machine 3 is at the drive units 5 of the 2 and 4 the proposed connection device 1 each with a connecting conductor 9 intended. The connection device 1 the drive units according to 3 and 4 were like in 1a-c described prepared.

The only difference between the drive units 5 of the 2 and 4 is that the first, detachable joints 9A produced in different ways. At the drive unit 5 according to 2 is the first connection points 9A by a screw connection between the connection 6 and the connection conductor 9 educated. At the drive unit 5 according to 4 is the first connection points 9A by a clamping by means of a clamping spring between the terminal 6 and the connection conductor 9 formed (see also 10 ).

The electric machine 3 according to 2 and 4 three windings on. This is a three-phase induction machine. The power electronics 2 is accordingly as an inverter with three phase connections 6 executed. These connections 6 are surrounded by a common plastic housing. In the area of the junction 9A lead the connections 6 out of the plastic housing. This plastic housing is on a circuit board 7 or a power module attached.

The housing of the electric motor 3 is open at one end (housing opening 11 ). This end face can later by a housing cover or a bearing plate for supporting a drive shaft of the electric motor 3 getting closed.

The power electronics 2 the drive unit 5 according to 2 is in 3 shown in an isometric view. The power electronics 2 the drive unit 5 according to 4 is in 5 shown in an isometric view. It turns out that this is the connections 6 surrounding plastic housing on a circuit board 7 or a power module of the power electronics 2 is attached. This circuit board 7 or this power module is within a trough-shaped housing of the power electronics 2 arranged, which is open towards the electric motor. The power electronics 1 This forms a module that is on the electric machine 3 can be placed.

The connections 6 protrude from the housing of the power electronics 2 out, in the direction where later the electric motor 3 should be arranged. The connections 6 protrude differently far in this direction. As a result, they resemble a contour of the electric motor 3 at.

The power electronics 2 of the 3 and 5 differ only by the different design of the connections 6 in the area of the later-produced first joint 9A , In the manufacture of the joint 9A by a screw connection ( 2 and 3 ) have the connections 6 have corresponding holes or holes (see also 8th ) while the connections 6 in the manufacture of the joint 9A by a clamping by means of clamping springs preferably each have a depression (see also 9 ). In the in 3 and 4 embodiment shown have the connections 6 Slotted holes.

The connection ladder 9 are according to 2 and 4 within the housing of the electric motor 3 arranged. They are surrounded by a common plastic housing, which is attached to the housing of the electric motor 3 is attached. At least in the area of the later connection points 9A . 9B the connecting conductors protrude 9 out of her plastic case. Each phase of the electric motor 3 is exactly a connection conductor 9 intended. The connection ladder 9 are identical to each other. They have an example of an L-shape. They are at different heights with respect to the electric motor 3 , This results in a step-like arrangement of the connecting conductor 9 , This arrangement is to the contour of the electric motor 3 customized.

In the area of the second connection point 9B have the connecting conductors 9 one eyelet each. This eyelet points towards the open end of the electric motor 3 , Thus, the coil ends of the windings 4 when inserted from the back of the eyelet into the open end of the electric machine 3 , A tool for making the second joints 9B can thus easily from the frontal housing opening 11 one after the other at the eyelets (see also 8th and 9 ).

A manufacturing process for the drive unit 5 according to 3 is in 6a-d shown. A manufacturing process for the drive unit 5 according to 4 is in 7a-d shown. The manufacturing processes are similar in their main steps. Only the production of the first connection points 9A is different (see 6c and 7c ).

According to 6a and 7a First, the modules "power electronics 2" and "E-machine 3" are provided. The housing of the electric machines 3 has (above) an area for receiving the power electronics 2 on. This area will later be replaced by the housing of the power electronics 2 covered. Within this housing area is a housing opening 8th provided by which the fixed connections 6 the power electronics are feasible. As a bulkhead seal, this opening can have a seal through which the connections 6 and optionally signal line (s) are feasible.

For example, over the frontal opening 11 in advance became the connecting conductors 9 within the housing of the electric motor 3 positioned. The winding ends of the windings 4 were also in advance in the eye of the respective liaison officer 9 introduced loosely. The second connection points 9B between the connecting conductors 9 and the respective winding 4 but they have not been made yet. Thus, the connecting conductors have 9 with respect to the windings 4 still a certain game on, for example, can be bridged by the tolerance variations.

According to 6b and 7b will be the power electronics first 2 on the electric machine 3 put on and fastened there, for example by a screw connection. When attaching the connections 6 through the opening 8th and in the area of the first junction 9A guided. The different lengths of the connections 6 correspond to the different arrangements of the connecting conductors 9 in height.

According to 6c and 7c now become the first, detachable connection points 9A produced. In the embodiment according to 2 (please refer 6c ) are the connections 6 with the respectively associated connection conductor 9 screwed. This is done through the housing opening 11 a screwing tool 10 used. In the embodiment according to 4 (please refer 7c ) are the connections 6 with the respectively associated connection conductor 9 clamped by a spring clip. This is done through the housing opening 11 a tool 10 used for bending and placing the spring clip. Such a tool 10 is for example in the DE 10 2016 208 291 A1 described.

According to 6c and 7c Only now are the second, permanent joints 9B educated. This is preferably done by pressure welding. This is done through the housing opening 11 a corresponding pressure welding tool 12 used. This compresses and heats the respective ends of the connecting conductors 9 (the eyelets) with the respective winding 4 , so that between these next to a positive connection (pressing) and a material bond (welding) is formed. Thus, the connecting device became 1 made the connections 6 with the windings 4 releasably and electrically conductive contacted.

8th and 9 each show a sectional view through a connecting device 1 during the production of the second insoluble joint 9B with the pressure welding tool 12 , so during the in 6d and 7d shown production step.

The pressure welding tool 12 can be constructed in several parts and, for example, from a movable stamp 12A and a solid matrix 12B between which are the parts 9 and 4 be pressed and heated.

In 8th and 9 is good that through the opening 8th the housing of the electric motor 3 guided connection 6 the power electronics 2 visible, as well as an associated connection conductor 9 with the connection points 9A . 9B , Likewise, the L-shape is the connection conductor 9 to recognize.

Inside the opening 8th is a seal 13 arranged as a bulkhead seal between the housing of the power electronics 2 and the housing of the electric motor 3 serves. Exemplary is through the opening 8th and the seal 13 also a signal line 14 guided.

8th shows an example by a screw 16 manufactured first connection point 9A , while 9 exemplified by a clamping by means of a spring clip 15 prepared joint 9A shows.

How out 8th indicates the connection 6 and the associated connection conductor 9 in each case a hole, which is penetrated by a screw. Together with a nut this causes the screwing of the two parts together and thus the connection point 9A ,

How out 9 shows, the connection points 6 an opening on and the associated connection conductor 9 a corresponding bulge, which by the spring clip 15 be jammed together. This will be the connection point 9A educated.

10 shows an isometric view of the connection device according to 9 , This is particularly good for the production of the joint 9B used spring clip 15 to recognize. In detail, this is a so-called cone clamp.

The spring clip 15 has two opposite spring arms 15A . 15B on. The spring arms 15A . 15B go from a middle area 15C the spring clip 15 V-shaped or cone-shaped (hence the name "cone clamp"). The middle area 15C serves as an attachment to the front, first contact partner (here, for example, the connection conductor 9 ). The spring arms 15A . 15B are designed to encompass at least this first contact partner from opposite sides and with the ends of the spring arms 15A . 15B in each case in or on the other, second contact partner (here, for example, the connection 6 ) to grasp this other contact partner against the voltage applied to the central area first contact partner. The spring clip 15 thus has a M or W shape in a cross section.

In addition to such a spring clip 15 are for making the first joint 9A Other types of spring clips can be used, for example, in the DE 10 2016 208 291 A1 described spring clips.

Due to the illustrated embodiment of the spring clip 15 can be easily made an electrical and mechanical connection between any two electrical contact partners. This type of connection is electrically highly resilient and resistant to vibration. It has fewer components than a classic screw connection. It can be mounted quickly and from one side of the contact partner.

The invention can therefore relate only to such a spring clip and / or to a mechanical and electrical connection between two contact partners by means of such a spring clip 15 , This spring clip 15 is characterized by the fact that it has at least two opposing spring arms 15A . 15B which has a central area 15C the spring clip 15 V-shaped or conical, with the middle region 15C for abutment against the first contact partner, and wherein the spring arms 15A . 15B are designed to encompass at least the first contact partner from opposite sides and to grip with their ends in or on the second contact partner to press this other contact partner against the voltage applied to the central region first contact partner.

In particular, such a spring clip 15 in a cross section on an M or W shape. The angles present within the M or W shape may be identical or different. In particular, the spring arms 15A . 15B mirrored to each other. In particular, such a spring clip 15 more than two spring arms 15A . 15B on. In particular, there is such a spring clip 15 made of spring steel. In particular, there is a means of the spring clip 15 made connection of at least one of the contact partners, in particular the first contact partner, made of a softer material than the spring clip 15 , The contact partners can consist of different materials.

LIST OF REFERENCE NUMBERS

1

connecting device

2

power electronics

3

E-machine

4

winding

5

drive unit

6

Connection, connection cable

6A, 6B

junction

7

circuit board

8th

housing opening

9

connecting conductors

9A, 9B

junction

10

Tool

11

housing opening

12

Tool

12A

stamp

12B

matrix

13

poetry

14

signal line

15

spring clip

15A

spring arm

15B

spring arm

15C

the central region

16

screw

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102016208291 A1 [0003, 0012, 0073, 0084]

Claims (17)

Connecting device (1) for releasably electrically conductive connection of a power electronics (2) for operating an electric motor (3) with an electrical winding (4) of the electric motor (3), with a connecting conductor (6), wherein a first electrically conductive connection point (9A) between a connection (6) of the power electronics (2) and the connection conductor (6) is provided, and wherein a second electrically conductive connection point (9B) between the connection conductor (9) and the winding (4 ) is provided, and wherein one of the first and second connection points (9A, 9B) is non-detachable and the other of the first and second connection points (9A, 9B) is detachable. Connecting device (1) after Claim 1 , wherein the first connection point (9A) is made detachable and the second connection point (9B) is designed to be non-detachable. Connecting device (1) according to one of the preceding claims, wherein the power electronics (2) is arranged in a separate housing and the electric machines (3) is arranged in a separate housing, and wherein the connection (6) of the power electronics (2) the housing of the power electronics (2) protrudes and projects through an opening (8) of the housing of the electric machines (3) in the housing of the electric machines (3), and wherein the first and second connection points (9A, 9B) within the Housing of the electric motor (3) are arranged. Connecting device (1) after Claim 3 , wherein the opening (8) of the housing of the electric machines (3) has a seal (13) through which the connection (6) of the power electronics (2) leads. Connecting device (1) after Claim 3 or 4 , wherein at least one signal line (14) between the electric motor (3) and power electronics (2) is provided, which leads through the opening (8). Connecting device (1) according to one of the preceding claims, wherein the connection (6) of the power electronics (2) comprises a plastic housing. Connecting device (1) after Claim 6 , wherein this plastic housing of the terminal (6) on • a printed circuit board (7) or a power module of the power electronics (2) and / or • a housing of the power electronics (2) is attached. Connecting device (1) according to one of the preceding claims, wherein the connecting conductor (9) comprises a plastic housing. Connecting device (1) after Claim 8 , wherein this plastic housing of the connecting conductor (9) is fixed to a housing of the electric motor (3). Connecting device (1) according to one of the preceding claims, wherein the connecting conductor (9) has at one end an eyelet for receiving the winding (4) for producing the second connection point (9B), and wherein the connecting conductor at another end for producing the second connection point (9A) is formed. Connecting device (1) according to one of the preceding claims, wherein the electric motor (3) has a plurality of windings (4) and the power electronics (2) has a corresponding plurality of terminals (6), and wherein a corresponding plurality of connecting conductors ( 9) is provided, in particular identical connecting conductors (9), which each one of the windings (4) with one of the terminals (6) of the power electronics (2) electrically conductively connect. Connecting device (1) after Claim 11 , wherein • the plurality of terminals (6) of the power electronics (2) have a common plastic housing, which is attached to a printed circuit board (7) or a power module of the power electronics and / or to a housing of the power electronics (2), and / or • the plurality of connection conductors (9) have a common plastic housing which is fixed to a housing of the electric motor (3). Connecting device (1) after Claim 11 or 12 , wherein the terminals (6) of the power electronics (2) are of different lengths and the connecting conductors (9) are of equal length. Method for producing a connection device (1) according to one of the preceding claims, characterized in that first the first connection point (9A) is produced and later the second connection point (9B) is produced. Method according to the preceding claim, wherein • the connecting conductor (9) is arranged in a housing of the electric motor (3), • the connecting conductor (9) is brought into the region of the winding (4) or vice versa, • the power electronics (2 ) is arranged on the electric motor (3), The connection (6) of the power electronics (2) is brought into the region of the connection conductor (9), • the first connection point (9A) is established between the connection (6) of the power electronics (2) and the connection conductor (9), the second connection point (9A) is established between the connection conductor (9) and the winding (4). Drive unit (5) with an electric motor (3) and with power electronics (2) for operating the electric motor (3) and with a connecting device (1) according to one of Claims 1 to 13 for releasably electrically conductive connection of the power electronics (2) with at least one electrical winding (4) of the electric motor (3). Vehicle drive system with a drive unit (5) according to Claim 16 , wherein the electric motor (2) is designed as a traction drive.

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