Patent Publication Number: US-2023150443-A1

Title: Driving arrangement, particularly for driving the vehicle

Description:
The present invention refers to a driving arrangement, particularly for driving a vehicle, comprising an electric machine and a housing, in which the electric machine is arranged, the housing having an opening, through which a supply cable for the electric machine extends. 
     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. 
     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 as initially described, further comprising a sealing device that comprises a carrier having a through-hole and being mounted within the opening and a sealing sleeve arranged within the through-hole, wherein the supply cable extends through the sealing sleeve. 
     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 30° and 90°. 
     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. 
     For example, the carrier has two further through-holes. In this case, 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 further through-hole is closed. As another alternative, the further through-holes are closed. 
     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.  1    a perspective view of a first embodiment of the driving arrangement according to the invention; 
         FIG.  2    a detailed view of the openings of the housing according to the first embodiment; 
         FIG.  3    a frontal view on the housing according to the first embodiment; 
         FIG.  4    a cross-sectional view of a sealing device depicted in  FIG.  3   ; 
         FIG.  5    a detailed view of a sealing sleeve of the sealing device depicted in  FIG.  4   ; 
         FIG.  6    a first detailed view of the carrier of the sealing device depicted in  FIG.  4   ; 
         FIG.  7    a second detailed view of the carrier of the sealing device depicted in  FIG.  4   ; 
         FIG.  8    a detailed view of the sealing ring of the sealing device depicted in  FIG.  4   ; 
         FIG.  9    a perspective view of the sealing devices according to a second embodiment; and 
         FIG.  10    a perspective view of the sealing devices according to a third embodiment. 
         FIG.  1    is a perspective view of a first embodiment of a driving arrangement  1 . The driving arrangement  1  is configured to drive the vehicle, such as battery electric vehicle or hybrid vehicle. 
     
    
    
     The driving arrangement  1  comprises an electric machine (hidden in  FIG.  1   ) and a housing  2 , in which the electric machine is arranged. A shaft  3  that connects the electric machine with the gearbox (hidden in  FIG.  1   ) is visible in  FIG.  1   , which is supported by a bearing arranged within an end shield portion  4  of the housing  2 . A maintenance box  5  of the driving arrangement  1  is formed by an outer surface  6  (see  FIG.  3   ) of the housing  2  and a removable cover  7 , Furthermore, the driving arrangement  1  comprises an inverter box  8 , which is formed by a further outer surface (hidden in  FIG.  1   ) of the housing  2  and a further removable cover  9 . Within the inverter box  8  an inverter (hidden in  FIG.  1   ) is disposed that provides a multiphase AC current for supplying stator windings of the electric machine. 
       FIG.  2    is a detailed view of openings  9 ,  10  of the housing  2  according to the first embodiment. As can be seen the housing has a first opening  9  and a second opening  10  that have the shape of a radiused triangle. Through the openings  9 ,  10  supply cables (not shown in  FIG.  1    to  FIG.  8   ) 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.  3    is a frontal view of the housing  2  according to the first embodiment. 
     The drive arrangement  1  comprises a first sealing device  11  mounted within the first opening  9  (see  FIG.  2   ) and the second sealing device  12  mounted within the second opening  10 . The sealing devices  11 ,  12  are substantially identical so that they are described in detail with reference to the first sealing device  11  only. 
     The sealing device  11  comprises a carrier  13 , a first sealing sleeve  14 , a second sealing sleep  15  and a third sealing sleeve  16 . Through each sealing sleeve  14 ,  15 ,  16  a supply cable extends from the outside of the housing  2  into the inside of the housing  2  in order to connect the electric machine. Each sealing sleeve  14 ,  15 ,  16  is arranged within one of three through-holes  17   a ,  17   b ,  17   c  (see  FIG.  6   ) of the sealing device  11 , The sealing sleeves  14 ,  15 ,  16  and made of rubber, whereas the carrier  13  is made of polyamide and, thus, more rigid than the sealing sleeves  14 ,  15 ,  16 . 
       FIG.  4    is cross-sectional view of the sealing device  11 . In the following the sealing sleeve  14 , also shown in a perspective view in  FIG.  5   , is described representatively for the other sealing sleeves  15 ,  16  of the sealing device  11 . 
     The sealing sleeve  14  comprises an angled portion  19  which allows the sealing sleeve  14  to follow are corresponding angled shape of the highly rigid cable that extends therethrough. The sealing sleeve  14  of the comprises a sealing lip  20  on its free and on the side of the housing to being opposite to the electric machine. Therein, the angled portion  19  is arranged between the sealing lip  20  and the housing  2 . 
     The other free end of the sealing sleeve  14  comprises a circumferential detent that overlaps the carrier  13  on its side facing the inside of the housing  2 . Furthermore, the sealing sleeve  14  comprises two circumferential sealing projections  22  that about a cylindrical surface  23  of the carrier  13 . Additionally, the sealing sleeve  14  comprises a circumferential collar  24  overlapping the carrier  13  on its side facing the outside of the housing  2 . 
       FIG.  6    and  FIG.  7    are each a perspective view of the carrier  13 . As can be seen the carrier  13  comprises a plate portion  25  from which for each through-hole  17   a ,  17   b ,  17   c  the cylindrical surface  23  extends into the inside of the housing  2 . On its side facing the inside of the housing  2  the carrier  13  comprises outside surfaces  26  that the surround of the through-holes  17   a ,  17   b ,  17   c  partially. 
     Again with reference to  FIG.  4   , it can be seen that a sealing ring  27 , which is shown in a perspective view in  FIG.  8   , is arranged between the carrier  13  and an edge  28  of the opening  9 . The sealing ring  27  is disposed along the outer surfaces  26  of the sealing device  11 . 
     The sealing device  11  is fixed to the housing  2  by means of a snap-fit that is realized by 3 snapping means  29  (see  FIG.  7   ) that are arranged between the outer surfaces  26 . 
       FIG.  9    is a perspective view of the sealing devices  11 ,  12  according to a second embodiment of a driving arrangement  1 . 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  30 ,  31 ,  32  are provided. Therein, the supply cable  30  extends through the first through-hole  17   a  and the supply cable  31  extends through the second through-hole  17   b  of the first sealing device  11 . The third through-hole  17   c  is closed by means of a plug  33 . The supply cable  32  extends through the first through-hole  17   a  of the second sealing device  12 . The second through-hole  17   b  and the third through-hole  17   c  of the second sealing device  12  are closed by means of plugs  33 . Thus, the same housing  2  and the same carrier  13  can be used for a six-phase and a three-phase electric machine. 
       FIG.  10    is a perspective view of the sealing devices  11 ,  12  according to a third embodiment of a driving arrangement  1 . As far as nothing else is mentioned in the following, the second embodiment corresponds to the first embodiment. 
     Instead of using plugs  33  for closing the third through-hole  17   c  of the first sealing device  11  and the second and third through-holes  17   b ,  17   c  of the second sealing device  12 , the number of through-holes  17   a ,  17   b  of a respective sealing device  11 ,  12  corresponds to the number of supply cables  30 ,  31 ,  22  that extend through the opening  9 ,  10 , in which the sealing device  11 ,  12  is mounted. The plate portion  25  of a respective carrier  13  extends closed in a respective corner portions, where no through-hole is provided.