Patent Publication Number: US-8534425-B2

Title: Method for regulating the level of a section of an oil tray comprising at least two sections

Description:
This application is a National Stage completion of PCT/EP2007/059182 filed Sep. 3, 2007, which claims priority from German patent application serial no. 10 2006 045 240.2 filed Sep. 26, 2006. 
     FIELD OF THE INVENTION 
     The present invention concerns a method for regulating the oil level in a section of an oil sump of a splash-lubricated transmission that comprises at least two oil sump sections. In addition, the invention concerns a device for regulating the oil level in a section of an oil sump of a splash-lubricated transmission that comprises at least two oil sump sections, and in particular a device for implementing the method according to the invention. 
     BACKGROUND OF THE INVENTION 
     Within a splash-lubricated transmission, in particular a transmission of step-down design, the various diameters of the gearwheels involved result in varying immersion levels of the gearwheels in the oil sump. If a pair of engaging gears is not immersed in the oil sump, or only insufficiently so, then adequate lubrication and cooling in the tooth engagement area is not ensured and, disadvantageously, this deficient lubrication results in premature wear of the running gearteeth. 
     From the prior art it is known, in order to raise or lower the oil level specifically in particular sections of the oil sump, to use baffle plates to produce individual oil sump sections in which the oil level can be raised or lowered for example by virtue of the housing wall or by means of grooves, but this solution, disadvantageously, entails additional costs. 
     SUMMARY OF THE INVENTION 
     The purpose of the present invention is to indicate a method for regulating the oil level in a section of an oil sump of a splash-lubricated transmission that comprises at least two oil sump sections, which ensures adequate lubrication and cooling of the gearwheels of the transmission. In addition, a device for regulating the oil level in a section of an oil sump that comprises at least two oil sump sections is provided, which is suitable for implementing the method according to the invention. 
     Accordingly, to regulate the oil level in a section of an oil sump comprising at least two oil sump sections, it is proposed that the oil splashing off a gearwheel immersed in one section of the oil sump is specifically deflected into another oil sump section. According to the invention the oil splashing off a gearwheel immersed in the sump is deflected into an adjacent oil sump section, these two sections being separated by a baffle plate, the oil passing through the baffle plate via an opening located above the desired oil level. 
     To deflect the splashing oil a deflector device is provided, preferably arranged directly on the baffle plate under the gearwheel from which the oil is coming. Oil is drawn out of the sump by the rotating gearwheel and flung off radially. It is then deflected upward and to the side by the deflector device, which is preferably formed as a bowl, so that the oil passes through the opening in the baffle plate to the back of the latter. The deflector device can also be made in some other suitable form. 
     Thanks to the concept according to the invention sufficient lubrication and cooling of the gearwheels of a splash-lubricated transmission is ensured in a simple and inexpensive manner. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Below, an example embodiment of the invention is explained in more detail with reference to the attached figures, which show: 
         FIG. 1 : Schematic front view of the device according to the invention for regulating the oil level in a section of an oil sump that comprises at least two oil sump sections; and 
         FIG. 2 : A partial schematic side view of the device according to the invention, along a section line 2-2 of in  FIG. 1 , for regulating the oil level in a section of an oil sump that comprises at least two oil sump sections. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS. 1 and 2  show a gearwheel  1  which rotates in the direction indicated by the arrow in a first oil sump section A of a splash-lubricating oil sump, the first oil sump section A being separated from a second oil sump section B by a baffle plate  2 . According to the invention, an opening  3  is provided in the baffle plate  2  above the oil level desired in the second, adjacent oil sump section B, through which the splashed oil is deflected into the second oil sump section B. 
     A preferably curved deflector device  4  is provided to deflect the splashed oil, and is positioned directly on the baffle plate  2  under the gearwheel 1  from which the oil is coming. Oil is drawn out of the first oil sump A by the gearwheel, directed radially, and deflected by the deflector device  4  upward and to the side so that it passes through the opening  3 , to the back of the baffle plate  2  and into the adjacent second oil sump section B where, as shown in  FIG. 2 , the oil is accommodated and maintained in the second sump section B at a higher oil level than the oil level in the first oil sump section A. The direction of movement of the oil is indicated in the figures by the arrows  5 . 
     INDEXES 
     
         
           1  Gearwheel 
           2  Baffle plate 
           3  Opening 
           4  Deflector device 
           5  Oil movement direction 
         A First Oil Sump 
         B Second Oil Sump