Disclosed is a tower lifting device for a rotary blasthole drill, comprising a hydraulic cylinder (5), an extending oil path (7), a retracting oil path (6), a speed control oil path (14) and a proximity switch (3), wherein the extending oil path (7) is connected to a non-rod-end chamber of the hydraulic cylinder (5), and an extension control unit is provided on the extending oil path (7); the retracting oil path (6) is connected to a rod-end chamber of the hydraulic cylinder (5), and a retraction control unit is provided on the retracting oil path (6); the speed control oil path (14) is connected to the retracting oil path (6), the speed control oil path (14) is connected to a speed control valve block (15) in series and the tail end thereof is connected to an oil tank (16); the proximity switch (3) is arranged on a tower supporting frame (2) for controlling the switching on and off of the speed control valve block (15), and when the tower (4) is approximately in a horizontal state, the speed control valve block (15) is on. By using such a tower lifting device in the present invention, the speed at which the tower is laid down to a horizontal state can be conveniently controlled.

Disclosed is a tower lifting device for a rotary blasthole drill, comprising a hydraulic cylinder (5), an extending oil path (7), a retracting oil path (6), a speed control oil path (14) and a proximity switch (3), wherein the extending oil path (7) is connected to a non-rod-end chamber of the hydraulic cylinder (5), and an extension control unit is provided on the extending oil path (7); the retracting oil path (6) is connected to a rod-end chamber of the hydraulic cylinder (5), and a retraction control unit is provided on the retracting oil path (6); the speed control oil path (14) is connected to the retracting oil path (6), the speed control oil path (14) is connected to a speed control valve block (15) in series and the tail end thereof is connected to an oil tank (16); the proximity switch (3) is arranged on a tower supporting frame (2) for controlling the switching on and off of the speed control valve block (15), and when the tower (4) is approximately in a horizontal state, the speed control valve block (15) is on. By using such a tower lifting device in the present invention, the speed at which the tower is laid down to a horizontal state can be conveniently controlled.

A method for operating a valve device for supplying compressed air to compressed air consumer includes the method comprising the steps of: determination of a first fluid pressure in a first section of a fluid passage of a valve assembly, which extends between an inlet port, and a valve element, determination of a second fluid pressure in a second section of the fluid passage of the valve assembly, which extends between the valve element and an outlet port, determination of a flow value for the valve element from the two fluid pressures and of a flow function, relating of the flow value with a presettable volumetric fluid flow rate or mass fluid flow rate for the pressurised fluid, which flow rate is provided for flow through the fluid passage, to a guide value and determination of a required actuating energy for an actuating device, and provision of the actuating energy to the actuating device.

A method for operating a valve device for supplying compressed air to compressed air consumer includes the method comprising the steps of: determination of a first fluid pressure in a first section of a fluid passage of a valve assembly, which extends between an inlet port, and a valve element, determination of a second fluid pressure in a second section of the fluid passage of the valve assembly, which extends between the valve element and an outlet port, determination of a flow value for the valve element from the two fluid pressures and of a flow function, relating of the flow value with a presettable volumetric fluid flow rate or mass fluid flow rate for the pressurised fluid, which flow rate is provided for flow through the fluid passage, to a guide value and determination of a required actuating energy for an actuating device, and provision of the actuating energy to the actuating device.

An actuator includes a cylinder, a first 2/2-way solenoid valve, a second 2/2-way solenoid valve, a fuzzy block, a controller, a source, a silencer, and a sensor. The cylinder is configured to receive a piston. The piston defines a first chamber and a second chamber inside the cylinder. The first 2/2-way solenoid valve includes an input terminal and a plurality of ports. The second solenoid valve includes an input terminal and a plurality of ports. The fuzzy block includes a plurality of phases each phase including a 2/2-way solenoid valve and a flow control valve for controlling the speed of movement of the piston within the cylinder. The controller is configured to issue a control signal for controlling the first and second 2/2-way solenoid valves and the 2/2-way solenoid valves included within the plurality of phases.

An actuator includes a cylinder, a first 2/2-way solenoid valve, a second 2/2-way solenoid valve, a fuzzy block, a controller, a source, a silencer, and a sensor. The cylinder is configured to receive a piston. The piston defines a first chamber and a second chamber inside the cylinder. The first 2/2-way solenoid valve includes an input terminal and a plurality of ports. The second solenoid valve includes an input terminal and a plurality of ports. The fuzzy block includes a plurality of phases each phase including a 2/2-way solenoid valve and a flow control valve for controlling the speed of movement of the piston within the cylinder. The controller is configured to issue a control signal for controlling the first and second 2/2-way solenoid valves and the 2/2-way solenoid valves included within the plurality of phases.

A work machine has a connecting valve which is positioned fluidly between a hoist actuator and a stick actuator to permit fluid flow between the hoist actuator and the stick actuator when the connecting valve is open. When the connecting valve is closed, fluid flow is inhibited between the hoist actuator and the stick actuator. A controller can receive information from a hoist boom position sensor and a stick boom position sensor, the controller can receive input from a user interface, and the controller can communicate signals to the hoist actuator and the stick actuator based upon the information from the hoist boom position sensor and the stick boom position sensor, and the input from the user interface.

Devices, systems, and methods for detecting properties of motion of at least one component of fluid exchange devices, such as, for example, a pressure exchange device or system.

Devices, systems, and methods for detecting properties of motion of at least one component of fluid exchange devices, such as, for example, a pressure exchange device or system.

A hydraulic driving device for a steam valve includes a plurality of hydraulic actuators to generate driving force to be transmitted to the valve body through a valve shaft of the steam valve. The hydraulic actuators each include a cylinder, a piston that is capable of reciprocating in the cylinder, and a rod having respective ends connected to the piston and valve shaft. The hydraulic actuators include a main actuator including a throttle portion for regulating a flow of pressure oil in a hydraulic chamber defined by the cylinder and piston so that a damping force is applied to the valve body during its closing operation. The one or more hydraulic actuators other than the main actuator include at least one sub actuator not having the throttle portion. The hydraulic chamber of the sub actuator communicates with the hydraulic chamber of the main actuator.