A valve structure (1) for driving reversible ploughs (40), comprising a first port (3) adapted to be in fluid communication with a pump (P) in a first configuration of the plough (40) and adapted to be in fluid communication with a tank (T) in a second reversed configuration of the plough (40), and a second port (4) adapted to be in fluid communication with the tank (T) in the first configuration of the plough (40) and adapted to be in fluid communication with the pump (P) in the second reversed configuration of the plough (40), a body (2) which includes a first seat (5) and a second seat (6), the seats housing respective moving spools (13, 14), a first interconnection port (7a) for the connection of the valve structure (1) to a first chamber (10a) of a first hydraulic cylinder (10) for longitudinally aligning the plough (40), and a second interconnection port (7b) for the connection to a second chamber (10b) of the first hydraulic cylinder (10), a third interconnection port (8a) for the connection of the valve structure (1) to a first chamber (12a) of a second hydraulic cylinder (12) for reversing the plough (40), and a fourth interconnection port (8b) for the connection to a second chamber (12b) of the second hydraulic cylinder (12). The valve structure (1) comprises hydraulic components configured to control the relative displacement of the spools (13, 14) to automatically control the movement of the cylinders (10, 12). A check valve (31) enables the fluid to flow in the second reversed configuration of the plough (40).

A pressing tool is described for plastically deforming a workpiece. The pressing tool comprises a piston pump driven by a motor that rotates in operating rotation direction RA and a pressure release valve and a coupling arrangement, which mechanically couples the motor to the pressure relief valve, so that the motor opens the pressure relief valve when operated in a loosening rotation direction RL opposite to the operating rotation direction RA. Also described is a corresponding method of operating a pressing tool.

A valve structure (1) for driving reversible ploughs (40), comprising a first port (3) adapted to be in fluid communication with a pump (P) in a first configuration of the plough (40) and adapted to be in fluid communication with a tank (T) in a second reversed configuration of the plough (40), and a second port (4) adapted to be in fluid communication with the tank (T) in the first configuration of the plough (40) and adapted to be in fluid communication with the pump (P) in the second reversed configuration of the plough (40), a body (2) which includes a first seat (5) and a second seat (6), the seats housing respective moving spools (13, 14), a first interconnection port (7a) for the connection of the valve structure (1) to a first chamber (10a) of a first hydraulic cylinder (10) for longitudinally aligning the plough (40), and a second interconnection port (7b) for the connection to a second chamber (10b) of the first hydraulic cylinder (10), a third interconnection port (8a) for the connection of the valve structure (1) to a first chamber (12a) of a second hydraulic cylinder (12) for reversing the plough (40), and a fourth interconnection port (8b) for the connection to a second chamber (12b) of the second hydraulic cylinder (12). The valve structure (1) comprises hydraulic components configured to control the relative displacement of the spools (13, 14) to automatically control the movement of the cylinders (10, 12). A check valve (31) enables the fluid to flow in the second reversed configuration of the plough (40).

Fluid equipment includes a container configured for having first and second fluids therein, a first fluid outlet/inlet path provided for outflow and inflow of the first fluid, a second fluid outlet/inlet path for outflow and inflow of the second fluid, and a member configured for moving in the container in response to pressure of the first fluid, the fluid equipment transmitting energy from the first to the second fluid. A first bellows is configured such that one end is closed in a sealed state by the moving member, the other end is fixed to an inner surface part of the container in a sealed state, and the inside of the first bellows communicates with the first fluid outlet/outlet path.

A pressing tool is described for plastically deforming a workpiece. The pressing tool comprises a piston pump driven by a motor that rotates in operating rotation direction RA and a pressure release valve and a coupling arrangement, which mechanically couples the motor to the pressure relief valve, so that the motor opens the pressure relief valve when operated in a loosening rotation direction RL opposite to the operating rotation direction RA. Also described is a corresponding method of operating a pressing tool.

Fluid equipment includes a container configured for having first and second fluids therein, a first fluid outlet/inlet path provided for outflow and inflow of the first fluid, a second fluid outlet/inlet path for outflow and inflow of the second fluid, and a member configured for moving in the container in response to pressure of the first fluid, the fluid equipment transmitting energy from the first to the second fluid. A first bellows is configured such that one end is closed in a sealed state by the moving member, the other end is fixed to an inner surface part of the container in a sealed state, and the inside of the first bellows communicates with the first fluid outlet/outlet path.

A first switching valve that switches between flow passages which allow communication between a first pressure-receiving chamber and a fluid supply device side and flow passages which allow communication between a second pressure-receiving chamber and the fluid supply device side, according to a change in a fluid pressure to be applied, and a second switching valve that is switched to flow passages which apply the fluid pressure to the first switching valve, are provided. The second switching valve includes return device, and is provided to be reciprocatable between an operation position to which the second switching valve is moved by a stroke of a piston and a return position to which the second switching valve is moved by the return device. The piston and the second switching valve are movable independently of each other.

A turbine valve actuator (100) controls a valve unit of a media-operated consumer unit, such as a steam or gas turbine, and has an actuating part drive (102) with a movable actuating part (104), a first media space (106) and a second media space (108). A pressure build up in the first media space (106) attempts to cause a movement of the actuating part (104) in a first direction (R). A pressure build-up in the second media space (108) attempts to cause a movement of the actuating part (104) in an opposing second direction (GR). The first media space (106) can be supplied with a fluid in predeterminable amounts by a supply (110). The second media space (108) is acted upon by a hydraulic accumulator (112) provided with a preload pressure and permanently connected to the second media space (108).

A first switching valve that switches between flow passages which allow communication between a first pressure-receiving chamber and a fluid supply device side and flow passages which allow communication between a second pressure-receiving chamber and the fluid supply device side, according to a change in a fluid pressure to be applied, and a second switching valve that is switched to flow passages which apply the fluid pressure to the first switching valve, are provided. The second switching valve includes return device, and is provided to be reciprocatable between an operation position to which the second switching valve is moved by a stroke of a piston and a return position to which the second switching valve is moved by the return device. The piston and the second switching valve are movable independently of each other.

A valve is for controlling flow of a pressurized fluid to a tool. The valve has a manifold, a poppet biased into an unseated position in which the pressurized fluid may flow from the manifold via a tank outlet, a piston configured to move the poppet into a seated position when the pressurized fluid flows into the manifold via the manifold inlet at a first fluid pressure, and a check valve biased into a closed position in which the pressurized fluid is prevented from flowing from the manifold via the tool outlet. A retainer retains the poppet relative to the piston and is configured so that when the poppet is in the seated position, the piston is independently movable relative to the poppet and thus permits the poppet to remain in the seated position upon variations in fluid pressure in the manifold.