Abstract:
Coupling system of a sealing assembly that has an annular rotating element, the seal assembly provides an annular screen providing a sleeve portion to be integrally coupled with the annular element rotating and a flange portion that protrudes radially from the sleeve portion. The sleeve portion by coupling with a seat mounting of the annular rotating element defined by an outer cylindrical surface of the mounting and including a first circumferential discontinuity cooperating with the sleeve portion to locally increase a reaction force of the cylindrical surface at the first circumferential discontinuity due to elastic radial pressure exerted by the sleeve portion on the mounting seat.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to Italian patent application no. 102015000021905 filed on Jun. 9, 2015, the contents of which are fully incorporated herein by reference. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to a coupling system of a sealing assembly with a rotating annular element. 
       BACKGROUND OF THE INVENTION 
       [0003]    Normally, within the framework of the rolling bearings, which the present invention will refer without thereby losing generality, the seal assemblies include an annular screen having a sleeve portion, which is coupled with a rotating annular element, in particular a bearing ring, by means of a mounting by interference in order to render angularly and axially integral with each other the annular screen and the rotating annular element. 
         [0004]    Such fittings for interference occur, normally, by placing on the annular shield, or on a part of it, an axial thrust linearly increasing intensity with increasing progressively in surface engagement between the sleeve portion and the rotating annular element. The annular screen is normally realized in a printed metal sheet and sheared so that, after assembly, the sleeve portion showing resiliently compressible against the seat assembly, and such that the radial compression of the sleeve portion exerted on the mounting seat causes a reaction force of the cylindrical surface of sufficient material to prevent any sealing of the screen shifts. 
         [0005]    Despite the precision in the positioning and in the assembly of annular screens of the seal assemblies, coupling systems of the type described above have not proved sufficiently reliable in terms of use, or under mechanical and thermal stress, having been found during some tests and operations of maintenance of the movement, albeit minor, the screens themselves than in the bearing rings, or with respect to the nominal design conditions. 
       SUMMARY OF THE INVENTION 
       [0006]    The object of the present invention is to provide a coupling system of a sealing assembly with a rotating annular element free from the drawbacks described above. 
         [0007]    According to the present invention there is provided a coupling system of a sealing assembly with a rotating annular element. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0008]    The invention will now be described with reference to  FIG. 1 , which, in section, illustrates a preferred embodiment of a coupling system of a sealing assembly with a rotating annular element of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    With reference to the attached drawing, numeral  1  indicates as a whole a coupling system of a sealing assembly  2  with a rotating annular element  3 , in particular a bearing ring  40 . 
         [0010]    The sealing assembly  2  is adapted to prevent the entry of contaminating material within the bearing  40 , and provides an annular screen  21 , which is keyed on a radial outer cylindrical surface  3   a  rotary ring  3 , and is normally made of a molded sheet metal and sheared. The screen  21  includes a sleeve portion  22  intended, in use, to couple integral with the rotating ring  3  and a flange portion  23  that projects in cantilever fashion, in the radial direction, from the sleeve portion  22 , and is shaped in such a way that, after fitting, the sleeve portion  22  is elastically compressible ring  3   a  against the surface  3 , and such radial compression ring  3  causes a reaction force directed in the direction radially opposite to portion  22  and towards the sleeve itself. 
         [0011]    In the embodiment illustrated in the annexed figure, the sleeve portion  22  is defined by two cylindrical layers  22   a  and  22   b  folded back on themselves, to which the layer  22   a  is mounted on the contact surface of the radial cylindrical outer ring  3   a    3  rotary, and the layer  22   b  is connected, on the one hand, with the layer  22   a  and, by an axially opposite side to the preceding side, with the portion  23  to the flange. However, the sleeve portion  22  may assume different geometries and conformations depending on the type of annular screen  21  adopted, for example, alternatively to that shown she attached figure, it may be composed of a single layer instead of two radially superimposed layers, but as here notes for the purposes of the present invention is that it is force fit onto the rotary  3  being the geometry of an example non-limiting embodiment. 
         [0012]    The coupling system  1  is adapted to influence the magnitude and distribution of the aforementioned restraining reaction between the surface  3   a  and the sleeve portion  22  and includes a mounting seat  10  to allow the coupling portion  22  of the sleeve with the ring  3  rotating ring. 
         [0013]    The contact between the seat  10  and the mounting portion  22  in the sleeve, or the elastic action of the sleeve portion  22 , radially directed toward a rotation axis (not shown) of the bearing  40 , determines a reaction force opposite and proportional entity the extension of the surface of mutual contact between the seat  10  and the mounting portion  22  in sleeve: in the known case in which there is full communion between the seat  10  and the mounting portion  22  in the sleeve, the restraining reaction is, in line of maximum, uniformly distributed along any contact director between the seat  10  and the mounting portion  22  in the sleeve. 
         [0014]    In the embodiment illustrated in the annexed figure, the seat assembly  10  includes a groove  11  or the annular groove formed in the ring  3  through the surface  3   a  and two annular edges, or circumferential discontinuities,  12  and  13 , which axially bound the throat  11  and cooperate with the sleeve portion  22  to increase locally, i.e., at the edges  12  and  13  same, the restraining reaction of the cylindrical surface  3   a  due to the resilient radial pressure exerted by the portion  22  in the sleeve  10  on the seat assembly. The groove  11  locates on the surface of the ring  3  two zones  3   a  and  5  cylindrical surface disposed axially on opposite sides of the throat  11  and of which the zone  4  is axially bounded by the edge  12  and an edge  6  of the inner ring  3 , while zone  5  is axially bounded by the edge  13  and by a rounded edge  7  of the outer ring  3 . 
         [0015]    The presence of both the groove  11  and, above all, of the edges  13  determines, along a director any contact between the seat  10  and the mounting portion  22  in the sleeve, a constraining distribution of the reaction which will be proportional to the extension of the surface of mutual contact between the seat  10  and the mounting portion  22  to the sleeve along the two zones  4  and  5 , and the extent of the local reaction forces at the two annular edges, or circumferential discontinuities,  12  and  13 . 
         [0016]    The presence of the two annular edges, or circumferential discontinuities,  12  and  13  causes a local increase of the reaction constrain between the seat  10  and the mounting portion  22  in the sleeve of greater intensity to an intensity of the average value of the reaction constrain resulting between the seat  10  mounting portion  22  and the sleeve along the two zones  4  and  5 , making it even more stable coupling between the screen  21  and the annular ring  3  rotating. 
         [0017]    Furthermore, the groove  11  can be created using the form tools such as to confer to the relative annular rims  12  and  13  respective shaped profiles and such that the stable coupling between the annular screen  21  and the rotary ring  3 , to suffer from the aforementioned axis of rotation, according to directions chosen in such a way as to increase even more the stability of the coupling between the annular screen  21  and the ring  3  rotating. By way of example, but not limiting, both edges  12  and  13  may have the same shaped profiles, for example, subtend respective angles of 90°, and the lines of action of the relative binding reactions are directed towards each other forming of the corners with the axis of rotation of amplitude equal to half the amplitude of the angle subtended by the edges  12  and  13  same. In the case where it was necessary to increase the stability of the coupling without acting to the detriment of ease of assembly, can then be provided by the edges of the shaped profiles  12  and  13  should increase the retaining action of the edge  13 , and that, instead, facilitate, the action of mounting, i.e., give the edge  12  a restraining reaction of intensity and direction such as not to facilitate assembly of the sleeve portion  22 . 
         [0018]    The profiling of the edges of the profiles  12  and  13  can be modulated by varying, for example, the radius of curvature of the groove  11 . 
         [0019]    Finally, to favor the action of stability and retention on the sleeve portion  22 , that is, on the screen  21 , not only contribute to the constraining reactions exercised by the edges  12  and  13 , together with the reaction force proportional to the extension of the surface of mutual contact between the seat  10  and the mounting portion  22  to the sleeve along the two zones  4  and  5 , but also contributes elastic contraction within the throat portion  11  of the sleeve  22 , which, due to the lack of contact, namely of direct contrast to the radial compression of the sleeve portion  22  exerted on the seat assembly  10  at the throat  11 , it tends to penetrate radially into the groove  11  itself once assembly is completed, by determining, therefore, an increase of the coupling constraint between the screen  21  and the ring  3 . 
         [0020]    Therefore, if the normal reaction force due to the hammering of the screen  21  on the ring  3  at the zones  4  and  5  also adds the effect of the reaction value constrain localized along the edges  12  and  13 , resulting an increase in stability of the hammering the same without any change of the screen  21 , and, not even ring  3  to the realization of the groove part  11 . That is, the coupling system  1  described above allows in an extremely simple and economical way to couple in a much more stable and reliable the complex  2  with the sealing ring  3  without, for another, requiring any increase of the thrust of the hammering.