A fluid pressure driving device includes a first air-fluid converter and a second air-fluid converter each configured to convert air pressure supplied from an air pressure source to fluid pressure, a fluid pressure actuator having a first pressure chamber and a second pressure chamber, an operation state acquisition unit configured to acquire an operation state of the fluid pressure actuator, and first and second air pressure valves respectively provided on first and second air supply paths, the first and second air supply paths being configured to supply air from the air pressure source to the first and second air-fluid converters respectively, wherein the control device is configured to control the first air pressure valve and the second air pressure valve on the basis of an acquired result from the operation state acquisition unit.

A piezohydraulic actuator system includes four chambers: a first chamber defined by a drive bellows filled with a hydraulic fluid and movable by a piezo actuator, a second chamber defined by a hydraulic cylinder filled with the hydraulic fluid, which defines a first output; a third chamber defined by an output bellows filled with the hydraulic fluid, which defines a second output; and a fourth chamber defining a reservoir of the hydraulic fluid. The drive bellows is hydraulically connected via a first check valve to the second chamber. A hydraulic piston in the hydraulic cylinder is coupled mechanically to the output bellows. The drive bellows is hydraulically connected via a second check valve to the fourth chamber. The hydraulic fluid reservoir is hydraulically connected via a third check valve to the output bellows, and the hydraulic cylinder is hydraulically connected via a fourth check valve to the output bellows.

A hydraulic actuator (1) is disclosed comprising a cylinder housing (2), a piston (5) with a piston rod (6) being displaceably arranged inside the cylinder housing (2) and a pressure amplifier (17) comprising an inlet section (18) with a pressure inlet port (20), an active section (19) with a high pressure outlet port (22), a low pressure chamber (32) and a high pressure chamber (38a). It is an objective of the invention to provide a hydraulic actuator (1) with a modular pressure amplifier (17). To this end, the hydraulic actuator (1) comprises a cartridge pressure amplifier (10) comprising a sleeve (10a) being arranged at least partially inside the piston rod (6), and wherein the pressure amplifier (17) is stationarily arranged inside the sleeve (10a).

This disclosure relates to methods and apparatuses for punching workpieces. A punching tool is configured to move during a punching stroke along a stroke axis towards a workpiece to be punched. The punching tool is configured to move away from the punched workpiece during a return stroke. The punching tool includes first and second components configured to be coupled hydraulically for concurrent movement along the stroke axis. The punching tool includes a punching drive for moving the first component along the stroke axis. The punching apparatus is configured to move the second component relative to the first component at a first transmission ratio during the punching stroke. The punching apparatus is configured to move the second component relative to the first component at a second transmission ratio in response to a reaction force of the workpiece exceeding a threshold value of the punching drive during the punching stroke.

Provided is an electromechanical-linkage hydraulic control gate valve actuator. The actuator includes a hand-operated speed-increasing gearbox assembly and a bidirectional throttle valve. In the present invention, a motor is driven to rotate through the hand-operated speed-increasing gearbox and thus a hydraulic system is driven to finally open and close a gate valve. An opening and closing speeds of the gate valve can be regulated and controlled through the bidirectional throttle valve. The present invention drives the motor through the hand-operated speed-increasing gearbox under emergency conditions such as repair and power failure, thereby controlling to open and close the gate valve. Meanwhile, a hydraulic system respectively regulates the speeds of two states of opening and closing through a bidirectional throttling technique, so as to effectively eliminate a water hammer phenomenon. The present invention has simple structure, light weight and modular installation, and enhances safety and reliability.

A hydraulic pressure amplifier arrangement (1) is described comprising a supply port (A1), a pressure outlet (A2) connected to the supply port via check valve means (3), an intensifier section (5) having a high pressure piston (6) in a high pressure cylinder (7), a low pressure piston (8) in a low pressure cylinder (9) and connected to the high pressure piston (6), and a control valve (12) controlling a pressure in the low pressure cylinder (9), wherein the control valve (12) comprises a hydraulically actuated valve element (13). Such a pressure amplifier arrangement should have a good operational behavior in a cost effective manner. To this end the control valve (12) comprises spring means 16 acting on the valve element (1) in a direction towards a starting position of the control valve.

Provided is an electromechanical-linkage hydraulic control gate valve actuator. The actuator includes a hand-operated speed-increasing gearbox assembly and a bidirectional throttle valve. In the present invention, a motor is driven to rotate through the hand-operated speed-increasing gearbox and thus a hydraulic system is driven to finally open and close a gate valve. An opening and closing speeds of the gate valve can be regulated and controlled through the bidirectional throttle valve. The present invention drives the motor through the hand-operated speed-increasing gearbox under emergency conditions such as repair and power failure, thereby controlling to open and close the gate valve. Meanwhile, a hydraulic system respectively regulates the speeds of two states of opening and closing through a bidirectional throttling technique, so as to effectively eliminate a water hammer phenomenon. The present invention has simple structure, light weight and modular installation, and enhances safety and reliability.

An inner cylinder inside an outer cylinder is disposed to be coaxial to an air pressure supply rod inside the inner cylinder. A first piston is disposed between the air pressure supply rod and the inner cylinder, a pneumatic chamber is disposed on a side of one surface (hydraulic surface) of the first piston in the inner cylinder, and a first hydraulic chamber is disposed on a side of the other surface. A second piston is disposed between the outer cylinder and the inner cylinder, and a second hydraulic chamber is disposed on a side of a surface of the second piston which is provided in the same direction as the hydraulic surface of the first piston in both of the cylinders. The inner cylinder is provided with a communication hole for transmitting a negative pressure along with movement of oil with which the first hydraulic chamber and the second hydraulic chamber are filled. In this configuration, it is possible to shorten an overall length of a fluid pressure cylinder.

A hydropneumatic device having pressure a working part with a working piston guided in the working part and an intensifier part with an intensifier piston guided in the intensifier part. A connecting section for a hydraulic connection of the working part and of the intensifier part provides a connecting line for passage of hydraulic fluid between the working part and the intensifier part. The connecting section includes an adapter component which can be mounted on the working part and the intensifier part, and in the interior of which the connecting line is formed. In the mounted state of the adapter component, an opening, which is provided at the side on the working part, of a hydraulic chamber of the working part is connected, via the connecting line, to an opening, which is provided at the side on the intensifier part, of a hydraulic chamber of the intensifier part.

This disclosure relates to methods and apparatuses for punching workpieces. A punching tool is configured to move during a punching stroke along a stroke axis towards a workpiece to be punched. The punching tool is configured to move away from the punched workpiece during a return stroke. The punching tool includes first and second components configured to be coupled hydraulically for concurrent movement along the stroke axis. The punching tool includes a punching drive for moving the first component along the stroke axis. The punching apparatus is configured to move the second component relative to the first component at a first transmission ratio during the punching stroke. The punching apparatus is configured to move the second component relative to the first component at a second transmission ratio in response to a reaction force of the workpiece exceeding a threshold value of the punching drive during the punching stroke.