Abstract:
The invention relates to a fluid-sealing electric motor connector ( 1 ) for a housing ( 70 ) of an electric motor ( 7 ), in particular an electric motor ( 7 ) of an engine cooling fan or of an ABS/ESP system of a motor vehicle, comprising a connector housing ( 10 ), which can be attached to the housing ( 70 ) and by means of which at least one electrical line ( 80 ) can be connected to the electric motor so as to be fluid-sealed to the electric motor ( 7 ), wherein the connector housing ( 10 ) can be fastened to the housing ( 70 ) by means of a locking spring ( 50 ) or a catch mechanism, wherein the fluid-sealing electric motor connector ( 1 ) can be fastened to the housing ( 70 ) in an easily detachable manner. The invention further relates to a motor, in particular an electric motor ( 7 ) for an engine cooling fan or an ABS/ESP system of a motor vehicle, or a completed electrical cable ( 8 ) for a motor ( 7 ), in particular an electric motor ( 7 ), wherein the motor ( 7 ) or the completed electrical cable ( 8 ) has a fluid-sealing electric motor connector ( 1 ) according to the invention.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a fluid-sealing electric motor connector for a housing of an electric motor, in particular an electric motor of an engine cooling fan or of an Antilock Braking System/Electronic Stability Program (ABS/ESP®) system of a motor vehicle. The invention further relates to a motor, in particular an electric motor for an engine cooling fan or of an ABS/ESP® system of a motor vehicle, or a ready-to-use electrical cable for such a motor. 
     For cost reasons, when producing electric motors, in particular direct current (DC) motors, deep-drawn parts are used for the housings thereof. In different applications, such as for example in engine cooling fans and/or in the ABS/ESP® area of motor vehicles, such electric motors have to be fluid-sealed, i.e. the electrical control and supply lines have to be inserted in a fluid-sealed manner via a sealing flange into the electric motor.  FIG. 1  of the drawings shows such a sealing flange  100  according to the prior art, wherein the sealing flange  100  itself is fluid-sealed relative to the housing  70  via an axial seal  105  and one respective electrical line  80  via a radial seal  106 . 
     The terminology used hereinafter for the seals is based upon the mechanical loading of the seal, i.e. a mechanically axially loaded seal is denoted as the axial seal and a mechanically radially loaded seal is denoted as the radial seal. The seals may, however, also be denoted according to the path of their sealing function, wherein the terms may be reversed, i.e. an axial seal is then denoted as the radial seal and a radial seal is denoted as the axial seal. 
     The sealing flange  100  according to the prior art is secured by means of self-tapping and/or self-cutting screws  102  to the housing  70 , wherein the screws  102  have to be supported via steel sleeves  101  in order to prevent setting behavior of the sealing flange  100  which is produced from a relatively flexible plastics material. Moreover, the screws  102  are micro-encapsulated  103  in the region of their screw holes  104  in the housing  70 , whereby said screws are also fluid-sealed relative to the housing  70 . By means of the micro-encapsulation  103 , the sealing flange  100  is only able to be removed again from the housing  70  by breaking open the micro-encapsulation  103 ; i.e. in the event of a repair, wherever possible the sealing flange  100  remains on the housing  70 , as otherwise the micro-encapsulation  103  would have to be carried out again. 
     The screw connection required for the axial contact of the sealing flange  100  is complex and relatively cost-intensive, as additional screw holes  104  have to be provided and said screw holes have to be sealed by means of special screws  102 . Moreover, the screwing process is relatively complicated, wherein micro-encapsulated screws  102  are expensive and the seal thereof (ca. 2000 ppm) is not always guaranteed in mass production. During the tapping process of the screws  102 , shavings are produced which are able to penetrate the interior of the housing  70 , which subsequently may cause damage during operation of the motor or to a printed circuit board which may lead to a breakdown of the entire motor. Moreover, the material consumption is increased by a screwing-on region of the sealing flange. 
     SUMMARY OF THE INVENTION 
     It is the object of the invention to specify an improved fluid-sealed connection, in particular an improved fluid-sealed electrical connection to a motor, in particular an electric motor. In this case, the connection is intended to be easier to handle than a conventional sealing flange, wherein the connection and/or the fastening to the housing is intended to be easily detachable from the housing and without damaging a component of the sealing flange. Moreover, the connection is intended to be inexpensive and use fewer components than in the prior art. Furthermore, it is intended that less relatively cost-intensive sealing material has to be used for fluid-sealing the connection. 
     The object of the invention is achieved by means of a fluid-sealing electric motor connector for a housing of an electric motor, in particular an electric motor of an engine cooling fan or of an ABS/ESP system of a motor vehicle; and a motor, in particular an electric motor for an engine cooling fan or an ABS/ESP system of a motor vehicle, or a ready-to-use electrical cable for a motor, in particular an electric motor. 
     According to the invention, instead of a sealing flange for the electrical lines of the motor, which may only be removed in a complex manner from a housing of a motor, a connector for the lines is provided, said connector being able to be fastened in a simple and convenient manner to the housing and also being easily detachable from the housing. The fluid-sealing connector according to the invention has a plug connector housing which may be plugged onto the housing, by means of which at least one electrical line is able to be connected to the motor so as to be fluid-sealed relative thereto. The plug connector housing may be fastened to the housing by means of a locking spring or a latch mechanism, whereby the fluid-sealing connector may be fastened to the housing in an easily detachable manner. 
     The invention permits fewer and less expensive components to be used than in the prior art, wherein a more effective fluid-sealed connection is provided for the motor, with a smaller outlay for the mounting devices. In comparison with the prior art set forth in the introduction, at least two micro-encapsulated screws are dispensed with, resulting in the sealing problem in the screw region of the sealing flange being eliminated and shavings not being produced by the screws being screwed and/or cut into the housing. In a motor with a printed circuit board this is advantageous, in particular, when the printed circuit board has SMD (surface mounted device) components. At least two steel sleeves which have to be fitted into the sealing flange are also dispensed with. 
     In this case, the connector for fluid-sealing the relevant electrical line and/or the connector relative to the housing, may have a radial seal and an axial seal or a sealing unit preferably made in one piece from the same material, which ensures an axial and radial fluid-seal of the line and/or of the connector relative to the housing. The plug connector housing of the connector preferably has a mounting portion, by means of which the connector may be fastened to the housing of the motor. The mounting portion which is preferably substantially cuboidal is able in this case to be plugged inwardly into the housing, through a recess in the housing, and is configured such that the connector may be blocked inside the housing. Moreover, the mounting portion may be configured on the plug connector housing such that the connector may be blocked outside the housing. 
     In one embodiment of the invention, the mounting portion may have a locking recess, preferably formed as a through-recess, into which the locking spring may be inserted for mounting the connector on the housing such that a wall of the housing may be clamped between the locking spring and a shoulder of the plug connector housing. In this case, it is preferable if the locking spring has at least one spring portion which is configured, in particular, as a preferably arcuate spring tab. 
     The respective spring portion of the locking spring in this case may be inserted into a relevant locking recess of the mounting portion such that a longitudinal end portion of the spring portion is located on the housing and a central portion of the spring portion is located inside on the mounting portion. In this case, the mounting portion is preferably configured such that the locking spring may be inserted with its respective spring portion inside the housing into the relevant locking recess. 
     In preferred embodiments of the invention, a relevant locking recess of the mounting portion is a through-recess. In this case, the locking spring is preferably configured such that it may be supported in the locked state in the mounting portion with the two longitudinal end portions thereof on the housing. In embodiments of the invention, in a locked state of the locking spring a blocking device of the locking spring bears in a locked manner in the locking recess against a blocking device in the locking recess. In this case, the blocking device of the locking spring is preferably configured as a blocking tab or a blocking projection and the blocking device of the locking recess is preferably configured as a blocking recess and/or a blocking shoulder. 
     In embodiments of the invention, the plug connector housing may be designed such that a sealing unit, for example a combined axial/radial seal, may be mounted between the plug connector housing and one side of the housing, in particular an outer face of the housing. Moreover, the plug connector housing may be designed such that a radial seal or a radial seal, configured in particular as a mat seal, is received in the plug connector housing, wherein the radial seal is mounted in the plug connector housing by means of a fixing device preferably configured as a fixing plate. 
     In embodiments of the invention, the axial seal on the shoulder of the connector may be provided outside the mounting portion, completely encircling the mounting portion. Moreover, the relevant radial seal may be provided inside the plug connector housing, wherein it fluid-seals the relevant electrical line relative to the plug connector housing. The plug connector housing may have a plurality of through-recesses, through which the electrical lines are able to extend. Moreover, the mounting portion may be configured as a plurality of domes which may be inserted through a plurality of through-recesses in the housing; the locking spring is then able to be inserted therein through recesses in the domes, in particular plugged through said recesses. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is described in more detail hereinafter with reference to exemplary embodiments and referring to the accompanying detailed drawings, in which: 
         FIG. 1  shows a sectional plan view of a sealing flange according to the prior art on a housing of an electric motor for an electrical supply line or control line of the electric motor; 
         FIG. 2  shows a perspective view from above and the front of a first variant of a fluid-sealing electric motor connector according to the invention, during the mounting thereof on a housing of an electric motor; 
         FIG. 3  shows a lateral sectional perspective view of the connector of  FIG. 2  in a mounted state in the region of its locking to the electric motor; 
         FIG. 4  shows a three-dimensional view of a locking spring for the connector; 
         FIG. 5  shows a perspective view of the connector, similar to  FIG. 2 , which shows the connector in a mounted state, wherein contact is made between the electric motor and electrical lines; 
         FIG. 6  shows a perspective view from the front and below of the connector in the mounted state, wherein the housing and/or the electric motor have been omitted for the sake of clarity; 
         FIG. 7  shows a first embodiment of the first variant of the connector according to the invention in a three-dimensional exploded view from above and the rear; 
         FIG. 8  shows a second embodiment of the first variant of the connector according to the invention, also in a three-dimensional exploded view from above and the rear; 
         FIG. 9  shows a perspective view from above and the front of a second variant of the fluid-sealing electric motor connector according to the invention in a mounted state on a housing of an electric motor; 
         FIG. 10  shows a perspective view from below and the rear of the mounted connector of  FIG. 9 ; 
         FIG. 11  shows a three-dimensional exploded view from above and the front of the connector during the mounting thereof on the housing of the electric motor; 
         FIG. 12  shows a three-dimensional exploded view from above and the rear of the connector during the mounting thereof on the housing; 
         FIG. 13  shows a sectional view through the mounted connector in the region of its locking to the housing; and 
         FIG. 14  shows a sectional view similar to  FIG. 13  but sectioned in the region of an electrical line passed through the connector. 
     
    
    
     DETAILED DESCRIPTION 
     Initially with reference to  FIGS. 2 to 8  of the drawings, the first variant of the fluid-sealing electric motor connector  1  according to the invention is described below with reference to two embodiments. The connector  1  has a plug connector housing  10  by means of which it may be fastened to a housing  70 , for example a pole housing  70  of an electric motor  7 . At least one electrical line  80  and/or at least one electrical cable  80  is passed through the connector  1  into the inside of the electric motor, said electrical line and/or cable then being electrically connected to an electrical conductor inside the electric motor  7  (see  FIG. 5 ). The electrical lines  80  provided on the connector  1  together with the connector  1  in this case form a ready-to-use electrical cable  8  and/or cable harness  8 . 
     The plug connector housing  10  is of substantially cuboidal construction with preferably rounded side walls, and on the front face thereof has a mounting portion  11 , wherein on the plug connector housing  10  in the transition to the mounting portion  11  thereof, a shoulder  13  is formed by means of which the connector  1  may be located on the housing  70 . The mounting portion  11  thus protrudes in such a state—a mounted state of the connector  1  on the housing  70 —through a through-recess  71  in the housing  70  inwardly into the housing  70 . In this case it is preferred that the connector  1  is locked inside the housing  70 , wherein the locking, together with the shoulder  13 , clamps a wall of the housing  70  therebetween; however an, optionally additional, external locking of the plug connector housing  10  to the housing  70  may also be used. 
     Such a locking may, for example, be implemented by means of latching devices, for example latching hooks formed on the mounting portion  11 , said latching devices being latched inside the housing  70  on suitable latching devices; this may, for example, be an internal wall of the housing  70  (not shown in the drawings). Moreover, latching devices, for example latching tabs or latching recesses, may be provided or configured on the plug connector housing  10 , such that said latching devices are latched with latching devices, for example latching recesses or latching hooks, outside on the housing  70  (also not shown in the drawings). Moreover, the locking is possible by means of a locking spring  50  or securing spring  50  which pulls the shoulder  13  of the plug connector housing  10  against the outer wall of the housing  70 , which is described in more detail below. 
     Such a locking spring  50 , which is preferably made in one piece from the same material and stamped from a metal sheet, is shown in more detail in  FIG. 4 , wherein the locking spring  50  preferably has three spring portions  52 , configured in particular as spring tabs  52 , on a web  51 . Naturally, there may be any number of spring portions  52 , the number thereof only corresponding to the number of locking recesses  12  in the mounting portion  11 . One respective spring portion  52  is preferably of arcuate configuration and provides a spring force perpendicular to its planar extent. 
     The respective spring portion  52  is connected to the web  51  by an attached longitudinal end portion  53 , is then lifted up in the direction of one free end  57  in a planar manner from a plane of the web  51  in the direction of its central portion  54 , in order to drop back again in the direction of a free longitudinal end portion  55  into the plane of the attached longitudinal end portion  53 . The free end  57  of the respective spring portion  52  is in turn lifted up in the same direction as the central portion  54 , in order to facilitate the insertion of the locking spring  50 . 
     Preferably, in the central portion  54  of the respective spring portion  52 , a blocking device  56  configured in particular as a blocking tab  56  or as a blocking projection  56  is provided, by means of said locking device a relevant spring portion  52  and/or the locking spring  50  being able to be latched in a relevant locking recess  12  in the mounting portion  11 , whereby the locking spring  50  is prevented from sliding out from the relevant locking recesses  12 . Preferably, only the two outer spring portions  52  have blocking devices  56  formed thereon. A blocking device  56  in this case engages and/or acts in the mounted state of the locking spring  50  in/on the mounting portion  11  in a blocking device  16  preferably formed as a blocking recess  16  and/or preferably formed as a blocking shoulder  16 , wherein the blocking device  16  is provided in a relevant locking recess  12  (see  FIG. 3 ). 
     The mounted state of the connector  1  on the housing  70  is also clearly seen in  FIG. 5 , wherein the locking spring  50  is inserted with each of its spring portions  52  into a corresponding locking recess  12  of the mounting portion  11 . In this case, the corresponding locking recesses  12  protrude inwardly into the housing  70 . In the mounted state, the relevant two longitudinal end portions  53 ,  55  of the locking spring  50  bear on the inside against the housing  70 , whereas the relevant central portion  54  bears on the inside against the respective locking recess  12 , and thus pretensions the mounting portion  11  and thus the plug connector housing  10  in the direction of the inside of the housing  70 , i.e. an axial seal  30  is axially loaded (see below). In other words, the relevant central portion  54  of the spring portions  52  bears against an edge of the relevant locking recess  12  directly adjacent to a free end of the mounting portion  11 . 
     To fluid-seal the connector  1  relative to the housing  70 , the connector  1  preferably has an axial seal  30  in a groove  15  of the plug connector housing  10  (see  FIG. 6 ). In this case, the groove  15  is machined into the shoulder  13  (see  FIG. 3 ) and preferably completely encircles the mounting portion  11  protruding from the shoulder  13 . Outside the groove  15 , projections  19  (see the second variant of the invention,  FIGS. 11 and 12 ) may be provided on the shoulder  13  which define a maximum axial compression path of the axial seal  30 . In the mounted state, the locking spring  50  pulls the axial seal  30  with its sealing portion  34  against an outer face of the housing  70 , whereby the plug connector housing  10  is fluid-sealed externally relative to the housing  70 . 
     Moreover, the connector  1  has a radial seal  20 ,  21  (see  FIGS. 7 and 8 ) which is fluid-sealed by means of an internal sealing portion  22  with regard to a relevant, or the relevant, electrical line  80  and by means of an outer seal portion  23  relative to the plug connector housing  10 . In this case, there are two embodiments. In the first embodiment shown in  FIG. 7 , each electrical line  80  is individually sealed, for which the plug connector housing  10  has one respective individual receiver  17 . In the second embodiment of the first variant shown in  FIG. 8 , a plurality, and in particular all, electrical lines  80  are sealed by a single radial seal  21 , preferably configured as a mat seal  21 , for which the plug connector housing  10  has a planar, for example rear, receiver  18 . 
     Both the individual radial seals  20  and the mat seal  21  are held in position by a fixing device  60  which may be fastened to the plug connector housing  10 , in particular secured by means of a tamper-evident device  61 . Moreover, the plug connector housing  10  has through-recesses  14  for the electrical lines  80 , wherein the lines  80  may be additionally secured to/in the plug connector housing  10 ; however it is also possible to pass the lines  80  simply through the plug connector housing  10 , without securing said lines to the plug connector housing  10 . Inside the housing  70 , the lines  80  are able to be connected to electrical connection devices  90 , wherein the lines  80  supply the electric motor  7  with electrical power for generating a torque and/or transmit control signals thereto and/or pass signals therefrom. 
     Moreover, a permissible degree of deformation and also a setting behavior of the sealing lips of the axial seal  30  may be relatively accurately set by the thickness and also the material of the locking spring  50 . Moreover, the locking spring  50  compensates for the relaxation of the material of the axial seal  30 , so that a fluid-seal is permanently ensured. The locking spring  50  in this case is designed such that it axially holds the plug connector housing  10  securely on the housing  70 , even in the case of vibrational stress. In this case, the connector  1  according to the invention may be used, for example, in electronically commutated (EC) and DC motors. 
     With reference to  FIGS. 9 to 14  of the drawings, the second variant of the fluid-sealing electric motor connector  1  according to the invention is described hereinafter with reference to one embodiment. In this case, details are only provided about features which differ from the first variant of the invention. In other words, features of the first variant may be transferred to the second variant of the invention; it is also possible to transfer the features of the second variant to the first variant of the invention. According to the second variant, the two separate components of the first variant which seal in a radial manner (axial seal  30 ) and in an axial manner (radial seal  20 ,  21 ) are combined into one sealing unit  40 , which is a combined axial/radial seal  40  and may take the form of a mat seal  40 . An internal sealing portion  42  in this case takes on the function of the above radial seal  20  and an outer sealing portion  43  the function of the above axial seal  30 . 
     In addition to lower material costs for the sealing unit  40 , the mounting time is also reduced, without the sealing behavior of the connector  1  being impaired. Relative to the above embodiment, the mounting portion  11  is no longer substantially cuboidal but configured as one, or a plurality of, preferably cylindrical dome(s)  11 . In this case, for the mounting of the connector  1  to the housing  70 , a longitudinal end portion of one respective dome  11  is moved forward through a separate through-recess  71  in the housing  70 . 
     Moreover, the housing  70  has through-recesses  72  for the electrical lines  80  adjacent to the through-recesses  71  for the domes  11 . Three cylindrical domes  11  are preferably formed on the plug connector housing  10  between four electrical lines  80 . Similar to the first variant of the invention, for locking the plug connector housing  10  to the housing  70 , the domes  11  have on their respective free longitudinal end portion a locking recess  12  into which the locking spring  50  may be inserted in a locked manner; which takes place in a similar manner to the first variant of the invention. 
     The sealing unit  40  is received in a front receiver  18  of the plug connector housing  10  and/or may be received during mounting of the connector  1  on the housing  70 , wherein the sealing unit  40  is clamped between the housing  70  and the plug connector housing  10 . In this case, the outer sealing portion  43  bears against the housing  70  and seals the plug connector housing  10  relative to the housing  70 . The inner sealing portions  42  seal the electrical lines  80  and the domes  11  relative to the housing  70 . Moreover, the domes  11  are in turn fluid-sealed, as the domes  11  are sealed on the inside behind the inserted locking spring  50  (see  FIG. 13 ) so that by means of the partially hollow domes  11  no fluid is able to penetrate the inside of the housing  70 . In this case, the domes  11  serve, on the one hand, for fastening the connector  1  to the housing  70  and, on the other hand, for saving material of the sealing unit  30 . 
     The sealing unit  40  is preferably designed (see  FIGS. 13 and 14 ) such that the inner sealing portion  42  is reduced relative to the outer sealing portion  43 , whereby sealing material is saved. In other words, the sealing unit  40  in the region of the through-recesses  71 ,  72  for the domes  11  and the electrical lines  80  is thicker in cross section than at other points, in particular a periphery on which the outer sealing portion  43  of the sealing unit  40  is preferably located. Preferably, the sealing unit  40  is configured in one piece from the same material as its sealing portions  42 ,  43 ; but it is possible to provide the sealing portions  42 ,  43  on a base body of the sealing unit  40 , in particular to bond said sealing portions thereto, in order to save further sealing material, as in such a case only the sealing portions  42 ,  43  are preferably formed from sealing material. 
     Moreover, in both variants of the invention it is possible to form a cover or a further housing part of the electric motor  7  (neither shown in the drawings) which closes, for example, the housing  70  in its mounted state and/or in the mounted state thereof on the housing  70 , in a portion adjacent to the locking spring  50 , such that for example a projection holds the locking spring  50  in its mounted position. This may also be transmitted to the housing  70 , which on the inside on a corresponding region has a projection or a recess which then holds the locking spring  50  in its mounted position. In the case of a recess in the housing  70 , the locking spring  50  then engages with a projection therein.