Patent ID: 8191573

Claim:
A pressure regulating valve for the protection of hydraulic assemblies of hydraulic longwall working, against rock burst and other sudden overload, comprising a valve housing ( 2 ) with a connection ( 4 ), an inlet side ( 5 ) and an outlet side ( 11 ) of the valve housing ( 2 ) being separated from one another by a closure device ( 12 ) which is movable against force of a valve spring ( 3 ) and features a sealing ring ( 10 ), with a fixed piston ( 9 ) and a hat-shaped valve spring plate ( 8 ) that is movable thereon, whereby during an overload said inlet and outlet sides are connected to one another via a three-step inner bore ( 14 ) in the connection ( 4 ) and the piston ( 9 ) and via radial bores ( 15 , 16 ) for discharging a pressure medium, a damping chamber ( 20 ) being configured between an upper side ( 17 ) of the piston ( 9 ) and a lower side ( 18 ) of the valve spring plate ( 8 ) and connected to the inlet side ( 5 ) via the inner bore ( 14 ), wherein the damping chamber ( 20 ) is connected to the inlet side ( 5 ) via the three-step inner bore ( 14 ), an uppermost partial bore ( 21 ) being configured as a throttle bore ( 22 ), while a partial bore ( 23 ) serving as a large-volume discharge bore ( 24 ) extends partially over the radial bores ( 15 , 16 ), and a central partial bore ( 25 ) has a reduced diameter relative to the discharge bore ( 24 ), and the central partial bore has a significantly larger diameter relative to the throttle bore ( 22 ).