Hydraulic damper for furniture doors and drawers

A hydraulic damper (1000) for use in furniture doors or drawers, the damper (1000) comprising a housing (1) that has a closed first end (14) and a second end that is provided with a lid (7);

• the damper (1000) further comprises a piston (2) that is movable in the housing (1) along a longitudinal piston axis (A);
• a piston rod (3) connected to the piston (2);
• the housing (1) is divided by the piston (2) to define a first chamber (11) and a second chamber (12) that are respectively at a first end side and a second end side of the piston (1);
• wherein
• the piston (2) comprises a circumferential groove (24) that is defined between a circumferential first shoulder (241) and a circumferential second shoulder (242) provided at a second end side with regard to the first shoulder (241);
• the piston rod (3) activating a damping of the piston (2);
• the groove (24) is provided with an annular collar (5) that is axially movable between the first shoulder (241) and second shoulder (242);
• the collar (5) is formed from an elastic material, and is arranged to reversibly contact to an inner surface (13) of the housing (1) when radially expanded when subjected to hydraulic pressure forces that are parallel to the axis (A);
• the first shoulder (241) is arranged to allow hydraulic fluid to flow on the collar (5) when the collar (5) is brought into contact with the first shoulder (241);
• the second shoulder (242) is arranged to block hydraulic fluid from flowing on the collar (5) when the collar (5) is brought into contact with the second shoulder (242);
• the piston (2) is provided with a channel (21) that is arranged to provide fluid flow communication between said first chamber (11) and second chamber (12);
• the collar (5) comprises a circumferential outer surface (51) facing the inner surface (13) of the housing (1), the outer surface (51) having a cylinder side surface geometry with a height (L);
• at zones that correspond to a trajectory of the piston (2) at its reciprocations along the axis (A), the inner surface (13) of the housing (1) has an inner diameter (D1) radial to said axis (A);
• and
• an L/D ratio between said height (L) and said inner diameter (D1) is 0.3 or higher.