Patent Description:
Driving arrangements that comprise an electric machine arranged within the housing have to be supplied with an electric current provided by one or multiple supply cables. Therefore, it is generally known to provide an opening in the housing, through which the supply cable extends.

Particularly with respect to automotive applications of the driving arrangement, a inside of the housing needs be protected against the ingress of water and/or dust. With respect to the feed-through of the supply cable into the housing, it has already been proposed to provide a sealing between the supply cable and the opening by potting with a bulk molding compound. However, potting is a difficult step of a manufacturing process of the driving arrangement and causes dirt when handling the compound.

<CIT> discloses a driving arrangement for driving a vehicle according to the preamble of claim <NUM>.

It is an object of the present invention to provide a driving arrangement with a simplified protection against the ingress of water and/or dust into a housing through the feedthrough of a supply cable.

According to the present invention the above object is solved by a driving arrangement according to claim <NUM>.

The invention is based upon the consideration to seal the opening of the housing by means of the carrier, that can be adjusted to the specific shape of the opening, and to realize a sealing between the carrier and the supply cable by means of the sealing sleeve, through which the supply cable extends. Thereby, the feed-through of the supply cable through the opening is simplified since the carrier can be mounted on the wire and attached to the housing. The sleeve can be slid over the supply cable and arranged in the through-hole of the carrier in order to form the sealing device. Thereby, dirt and hardly automatable assembly steps that come along with conventional potting technologies can be avoided.

Preferably, the sealing sleeve is less rigid than the carrier. This allows to realize the mechanical stability of the feedthrough by means of the carrier on the one hand and to realize the function of sealing the supply cable against the carrier by means of the sealing sleeve on the other hand. Additionally or alternatively, the sealing sleeve may be less rigid than the supply cable. This allows to provide the sealing to rather rigid supply cables that are capable of conducting large amounts of current, particular when using the driving arrangement to drive the vehicle.

Preferably, the sealing sleeve is made of rubber and/or the carrier is made of plastic, e.g. polyamide.

Advantageously, the sealing sleeve comprises an angled portion on its side facing the outside of the housing. Thereby, the supply cable can be bent directly after passing through the opening in order to save mounting space within the driving arrangement. The angle portion may have an angle between <NUM>° and <NUM>°.

Preferably, the sealing sleeve comprises a sealing lip that extends circumferentially around the supply cable. Thereby, an effective sealing between the sealing sleeve and the supply cable can be realized. The sealing lip may be arranged at a free end of the sealing sleeve. Typically, the angled portion is arranged between the sealing lip and the housing.

With respect to the driving arrangement according to the invention, it is preferred that the sealing sleeve comprises a circumferential detent that overlaps the carrier on its side facing the inside of the housing. This allows an simplified fixation of the sealing sleeve at the carrier.

Advantageously, the sealing sleeve comprises a circumferential collar overlapping the carrier on its side facing the outside of the housing. Thereby, it can be avoided that the sealing sleeve is pushed too much into the through-hole of the carrier during assembly.

Preferably, the carrier comprises a plate portion that covers an edge of the opening. Furthermore, the through-hole may be surrounded by a cylindrical surface of the carrier that extends from the plate portion towards the inside of the housing.

According to a preferred embodiment, the sealing sleeve may comprise one or multiple circumferential sealing projections that abut the cylindrical surface. This realizes an effective axial sealing between the carrier and the sealing sleeve. Typically, the sealing projections are elastically deformed between the supply cable and the carrier.

With regard to the driving arrangement according to the invention, it is furthermore preferred that the sealing device comprises a sealing ring arranged between the carrier and the opening. The sealing ring provides an effective axial sealing between the opening and the carrier. Typically, the sealing ring extends along an outside surface that is opposite to the cylindrical surface surrounding the through-hole.

In order to simplify the mounting of the sealing device within the opening, it is preferred that the carrier is fixed to the housing by means of a snap-fit. Therein, one or multiple snapping means may extend from the carrier, particular from the plate portion, towards the inside of the housing.

Preferably, the carrier and/or the opening has or have the shape of the radiused triangle. This allows an optimized shape of the feedthrough when using three supply cables with respect to provide a three- or six-phase alternating current of the electric machine, as described in detail below.

Preferably, the carrier has one or two further through-holes.

More preferably, a further sealing sleeve is arranged in each further through-hole and a further supply cable extends through the further sealing sleeve. Alternatively, a further sealing sleeve is arranged in one of the further through-holes and a further supply cable extends through the further sealing sleeve, wherein the other through-hole is closed. Alternatively, the further through-hole or the further through-holes is or are closed. Thereby, a uniform housing may be adapted to different phase configurations of the electric machine. The through-hole may be closed by a plug.

Typically the or each through-hole is arranged within corner portions of the radiused triangle.

It is possible that the housing comprises a further opening through which a supply cable for the electric machine extends, wherein a further sealing device is mounted in the further opening. Therein, six supply cables may be provided, wherein three supply cables extend through the first opening and three supply cables extend to further opening. Thereby, a six-phase electric machine can be supplied. Alternatively, three supply cables are provided, wherein one supply cable may extend though one of the openings and two supply cables extend through the other opening. Thereby, a three-phase electric machine can be supplied.

All statements referring to the opening, the supply cable, the sealing sleeve and the sealing device may apply correspondingly to the further opening, the further supply cables, the further sealing sleeves or the further sealing device, respectively.

Additionally, the driving arrangement may further comprise an inverter, wherein the or each supply cable is part of an electrical connection between the inverter and the electric machine. Preferably, the sealing device or the sealing devices are arranged within a maintenance box, formed by an outer surface the housing and a removable cover element.

Further details and advantages are disclosed in the following embodiments, wherein reference is made to the drawings. The drawings are schematic and show:.

<FIG> is a perspective view of a first embodiment of a driving arrangement <NUM>. The driving arrangement <NUM> is configured to drive the vehicle, such as battery electric vehicle or hybrid vehicle.

The driving arrangement <NUM> comprises an electric machine (hidden in <FIG>) and a housing <NUM>, in which the electric machine is arranged. A shaft <NUM> that connects the electric machine with the gearbox (hidden in <FIG>) is visible in <FIG>, which is supported by a bearing arranged within an end shield portion <NUM> of the housing <NUM>. A maintenance box <NUM> of the driving arrangement <NUM> is formed by an outer surface <NUM> (see <FIG>) of the housing <NUM> and a removable cover <NUM>. Furthermore, the driving arrangement <NUM> comprises an inverter box <NUM>, which is formed by a further outer surface (hidden in <FIG>) of the housing <NUM> and a further removable cover <NUM>. Within the inverter box <NUM> an inverter (hidden in <FIG>) is disposed that provides a multiphase AC current for supplying stator windings of the electric machine.

<FIG> is a detailed view of openings <NUM>, <NUM> of the housing <NUM> according to the first embodiment. As can be seen the housing has a first opening <NUM> and a second opening <NUM> that have the shape of a radiused triangle. Through the openings <NUM>, <NUM> supply cables (not shown in <FIG>) for the electric machine extend. In the present embodiment, the supply cables are a part of an electric connection between the inverter and the electric machine. In the present embodiment, the electric machine in a six-phase synchronous machine, so that six supply cables are provided.

<FIG> is a frontal view of the housing <NUM> according to the first embodiment.

The drive arrangement <NUM> comprises a first sealing device <NUM> mounted within the first opening <NUM> (see <FIG>) and the second sealing device <NUM> mounted within the second opening <NUM>. The sealing devices <NUM>, <NUM> are substantially identical so that they are described in detail with reference to the first sealing device <NUM> only.

The sealing device <NUM> comprises a carrier <NUM>, a first sealing sleeve <NUM>, a second sealing sleep <NUM> and a third sealing sleeve <NUM>. Through each sealing sleeve <NUM>, <NUM>, <NUM> a supply cable extends from the outside of the housing <NUM> into the inside of the housing <NUM> in order to connect the electric machine. Each sealing sleeve <NUM>, <NUM>, <NUM> is arranged within one of three through-holes 17a, 17b, 17c (see <FIG>) of the sealing device <NUM>. The sealing sleeves <NUM>, <NUM>, <NUM> and made of rubber, whereas the carrier <NUM> is made of polyamide and, thus, more rigid than the sealing sleeves <NUM>, <NUM>, <NUM>.

<FIG> is cross-sectional view of the sealing device <NUM>. In the following the sealing sleeve <NUM>, also shown in a perspective view in <FIG>, is described representatively for the other sealing sleeves <NUM>, <NUM> of the sealing device <NUM>.

The sealing sleeve <NUM> comprises an angled portion <NUM> which allows the sealing sleeve <NUM> to follow are corresponding angled shape of the highly rigid cable that extends therethrough. The sealing sleeve <NUM> of the comprises a sealing lip <NUM> on its free and on the side of the housing to being opposite to the electric machine. Therein, the angled portion <NUM> is arranged between the sealing lip <NUM> and the housing <NUM>.

The other free end of the sealing sleeve <NUM> comprises a circumferential detent that overlaps the carrier <NUM> on its side facing the inside of the housing <NUM>. Furthermore, the sealing sleeve <NUM> comprises two circumferential sealing projections <NUM> that about a cylindrical surface <NUM> of the carrier <NUM>. Additionally, the sealing sleeve <NUM> comprises a circumferential collar <NUM> overlapping the carrier <NUM> on its side facing the outside of the housing <NUM>.

<FIG> are each a perspective view of the carrier <NUM>. As can be seen the carrier <NUM> comprises a plate portion <NUM> from which for each through-hole 17a, 17b, 17c the cylindrical surface <NUM> extends into the inside of the housing <NUM>. On its side facing the inside of the housing <NUM> the carrier <NUM> comprises outside surfaces <NUM> that the surround of the through-holes 17a, 17b, 17c partially.

Again with reference to <FIG>, it can be seen that a sealing ring <NUM>, which is shown in a perspective view in <FIG>, is arranged between the carrier <NUM> and an edge <NUM> of the opening <NUM>. The sealing ring <NUM> is disposed along the outer surfaces <NUM> of the sealing device <NUM>.

The sealing device <NUM> is fixed to the housing <NUM> by means of a snap-fit that is realized by <NUM> snapping means <NUM> (see <FIG>) that are arranged between the outer surfaces <NUM>.

<FIG> is a perspective view of the sealing devices <NUM>, <NUM> according to a second embodiment of a driving arrangement <NUM>. As far as nothing else is mentioned in the following, the second embodiment corresponds to the first embodiment.

In the second embodiment the electric machine is a three-phase synchronous machine, so that three supply cables <NUM>, <NUM>, <NUM> are provided. Therein, the supply cable <NUM> extends through the first through-hole 17a and the supply cable <NUM> extends through the second through-hole 17b of the first sealing device <NUM>. The third through-hole 17c is closed by means of a plug <NUM>. The supply cable <NUM> extends through the first through-hole 17a of the second sealing device <NUM>. The second through-hole 17b and the third through-hole 17c of the second sealing device <NUM> are closed by means of plugs <NUM>. Thus, the same housing <NUM> and the same carrier <NUM> can be used for a six-phase and a three-phase electric machine.

<FIG> is a perspective view of the sealing devices <NUM>, <NUM> according to a third embodiment of a driving arrangement <NUM>. As far as nothing else is mentioned in the following, the second embodiment corresponds to the first embodiment.

Claim 1:
Driving arrangement (<NUM>), particularly for driving a vehicle, comprising
- an electric machine,
- a housing (<NUM>), in which the electric machine is arranged, the housing (<NUM>) having an opening (<NUM>), through which a supply cable (<NUM>) for the electric machine extends, and
- a sealing device (<NUM>) that comprises
- a carrier (<NUM>) having a through-hole (17a) and
- a sealing sleeve (<NUM>) arranged within the through-hole (17a), wherein the supply cable (<NUM>) extends through the sealing sleeve (<NUM>)
characterized in that
the carrier (<NUM>) is mounted within the opening (<NUM>) and comprises a plate portion (<NUM>) that covers an edge (<NUM>) of the opening (<NUM>), wherein the through-hole (17a) is surrounded by a cylindrical surface (<NUM>) of the carrier (<NUM>) that extends from the plate portion (<NUM>) towards the inside of the housing (<NUM>), wherein the sealing sleeve (<NUM>) comprises one or multiple circumferential sealing projections (<NUM>) that abut the cylindrical surface (<NUM>).