Patent ID: 7175008

Claim:
A decelerating device insertable between two members which are moveable relative to each other, said device comprising a casing defining internally a chamber filled with a viscous fluid; a movable member fitted in fluid-tight manner to the casing so as to be housed at least partly inside said chamber and immersed in the viscous fluid; partition means for dividing the chamber, substantially in fluid-tight manner, into at least two adjacent portions varying in volume as a function of a relative position of the movable member with respect to the casing; and calibrated constriction means for maintaining a permanent hydraulic connection of said at least two adjacent portions of the chamber, so that said viscous fluid flows, with a given resistance, between said at least two adjacent portions as a consequence of a relative motion between the movable member and the casing; wherein said casing is of elongated, cylindrical axial symmetry; said movable member is defined by a cylindrical pin, which is fitted to the casing, is housed at least partly inside the casing, clicks into an axially locked position inside the casing, and is inserted through an open end of the casing; said cylindrical pin comprises an axial portion housed in fluid-tight manner inside said chamber of the casing to define a rotor immersed in said viscous fluid filling the chamber, and a head projecting from said open end of the casing; said partition means comprise at least one radial rib extending along a whole length of said axial portion of the pin, and so sized as to cooperate in sliding manner, in use, with a cylindrical inner lateral wall of said chamber of the casing, and a saddle-shaped projection extending along an angular portion of a given size of said inner lateral wall of said chamber; said projection defines a cylindrically symmetrical seat, on which a cylindrical outer lateral wall of said axial portion of the pin rests and slides in use, so that said at least one rib and said projection support and guide said pin inside said chamber; a first end of said axial portion and said head of the pin are separated by a cylindrical stop surface larger in diameter than the axial portion of the pin, and such as to mate with said cylindrical inner lateral wall of said chamber, at said open end of the casing; and by a collar which clicks inside a groove formed in said cylindrical inner lateral wall of the chamber, at said open end of the casing; said device further comprises, between said cylindrical stop surface and said collar, a sealing ring being inserted inside a seat on the pin, and cooperating with the cylindrical inner lateral wall of the chamber; and a second, opposite end of said axial portion is fitted and rests axially inside a cylindrical seat, which is defined by a recess formed in said chamber, in an end wall of said casing, and faces said open end of the casing.