MANUFACTURING PROCEDURE OF A ROTULA BEARING.

摘要

Method of manufacturing a bearing (1) of the so-called ball joint type, especially provided with, - a first element (2) which, partially spherical and indicated by the term "sphere" has at least two functional surfaces (201 , 202), which are: - an external surface, called first surface (201), which defines a spherical ring delimited between two opposite faces (202, 203) substantially orthogonal to the axis (204) of the ring, - a second element (3 ) which, annularly and indicated with the term "cage", has at least two functional surfaces (301, 302), which are: - an external surface, called third surface (301), substantially cylindrical of revolution, intended to allow a mechanical connection with a bearing support element (4), - an internal surface, called fourth surface (302), intended to cooperate with the first surface (201) of said first element (2), being planned a radial play (5) of a pri mer predetermined value (51) between said first surface (201) and fourth surface (302), so that, according to this procedure, to manufacture the bearing (1), after having constituted the first element (2) called "sphere" : - during a first phase (20), the second element (3) called "cage" is formed by molding a first material (300), and this, at least in two assemblies (303, 304, 305, 306 ) at least according to a joint plane (307, 308) chosen to allow the positioning of said parts in the sphere (2), and this with a radial clearance (5) of a second predetermined value (52), - during a second phase (30), the different parts (303, 304, 305, 306) of the cage (3) are assembled on the sphere (2) so that they are in the operating position and, after assembly, - during a third phase (40), a third element (6), indicated with tea, is formed around the different parts (303, 304, 305, 306) of the cage (3) tying term, to maintain said different parts (303, 304, 305, 306) exercising on these last radial actions ("R") oriented towards the geometric center (206) of the sphere (2), and adjusting the intensity of these radial actions ("R") in order to modify, by means of the deformation of the cage, the radial clearance (5) and adjust this set to make it pass from the second predetermined value (52) to the first predetermined value (51), this procedure being characterized by the fact that in order to constitute the third element called the binding element (6): - a second material (600) of injection moldable type is chosen, then - at least by test, the coefficient of retraction (601) of said second material (600), then - depending on said retraction coefficient (601), at least per test, the second radial play value (52) is determined so that after molding of the tying element (6), the latter applies to the cage (3) radial actions that deform it in a controlled way and that, by modifying the radial play (5), regulate the radial play (5) over the first predetermined value (51), then - a mold (7) is formed that defines a cavity around those of the parts (303, 304, 305, 306) that constitute the cage (3), and after having positioned in the mold (7) an assembly consisting of a sphere (2) and a cage ( 3), then - the tying element (6) is formed by molding said second material (600) around the different parts (303, 304, 305, 306) of the cage (3) in order to elastically maintain said different parts (303, 304, 305, 306) of the cage (3) and, during solidification of the second material (600), as a consequence of the retraction of the second material (600), and of imposing on these parts of the box ( 3) the radial tensions that will allow to adjust the radial play 5 on the first value (51).