Hydraulically damped hinge for hinging a closure member to a support

A hydraulically damped hinge for hinging a closure member to a support, the hinge comprising:

• a first hinge member configured to be fixed to one of:
• the support and the closure member, the first hinge member comprising a cylinder barrel having a longitudinal direction;
• a second hinge member pivotably mounted on the first hinge member, the second hinge member being configured to be fixed to the other one of:
• the support and the closure member;
• and
• a dashpot interposed between said hinge members and configured for damping a closing movement of said closure member, the dashpot comprising:
• said cylinder barrel;
• a closed cylinder cavity formed within the cylinder barrel and being filled with a volume of hydraulic fluid;
• a damper shaft which extends into the cylinder cavity and is connected to the second hinge member, the cylinder barrel and the damper shaft being rotatable with respect to one another about a rotation axis which is substantially parallel to the longitudinal direction;
• and
• a piston within said cylinder cavity so as to divide the closed cylinder cavity into a high pressure compartment and a low pressure compartment, the piston being operatively coupled to said damper shaft to be slideable between two extreme positions in said longitudinal direction upon a relative rotation between said cylinder barrel and said damper shaft,
• wherein said hinge members are made of a synthetic material and in that the damper shaft is made of metal,
• wherein the dashpot further comprises:
• a one-way valve allowing fluid flow from the low pressure compartment to the high pressure compartment when said closure member is being opened;
• a restricted fluid passage between the high pressure compartment and the low pressure compartment which determines a closing speed of the closure member, the restricted fluid passage being formed by a plurality of bores within the damper shaft, at least one bore of said plurality of bores extending in said longitudinal direction;
• and
• an adjustable valve configured to regulate a fluid flow through said restricted fluid passage, said adjustable valve being placed in said at least one bore, said adjustable valve being made from a material having a higher thermal expansion coefficient than the metal of the damper shaft.