A pressure medium cylinder (1) for moving a toothed bar (3), comprising a toothed bar (3) on at least one side of which is formed a toothing (4). Inside the toothed bar (3), a cavity (6, 6a, 6b) is formed, extending to at least one end (7a, 7b) of the toothed bar. The pressure medium cylinder (1) further comprises a longitudinal structure (8, 8a, 8b), the longitudinal structure (8, 8a, 8b) and the toothed bar (3) being adapted movably in relation to each other, and the longitudinal structure (8, 8a, 8b) is adapted at least partly inside said cavity (6, 6a, 6b). The toothed bar (3) and longitudinal structure (8, 8a, 8b) are adapted in a sealed manner in relation to each other so that the toothed bar and the longitudinal structure are movable in relation to each other by the effect of a pressure medium.

A pressure medium cylinder (1) for moving a toothed bar (3), comprising a toothed bar (3) on at least one side of which is formed a toothing (4). Inside the toothed bar (3), a cavity (6, 6a, 6b) is formed, extending to at least one end (7a, 7b) of the toothed bar. The pressure medium cylinder (1) further comprises a longitudinal structure (8, 8a, 8b), the longitudinal structure (8, 8a, 8b) and the toothed bar (3) being adapted movably in relation to each other, and the longitudinal structure (8, 8a, 8b) is adapted at least partly inside said cavity (6, 6a, 6b). The toothed bar (3) and longitudinal structure (8, 8a, 8b) are adapted in a sealed manner in relation to each other so that the toothed bar and the longitudinal structure are movable in relation to each other by the effect of a pressure medium.

An apparatus for damping an actuator includes an inerter. The inerter includes a first terminal and a second terminal movable relative to one another along an inerter axis and configured to be mutually exclusively coupled to a support structure and a movable device actuated by an actuator. The inerter further includes a rod coupled to and movable with the first terminal and a threaded shaft coupled to and movable with the second terminal. The inerter further includes a flywheel having a flywheel annulus coupled to one of the rod and the threaded shaft. The flywheel is configured to rotate in proportion to axial acceleration of the rod relative to the threaded shaft in correspondence with actuation of the movable device by the actuator.

An apparatus for damping an actuator includes an inerter. The inerter includes a first terminal and a second terminal movable relative to one another along an inerter axis and configured to be mutually exclusively coupled to a support structure and a movable device actuated by an actuator. The inerter further includes a rod coupled to and movable with the first terminal and a threaded shaft coupled to and movable with the second terminal. The inerter further includes a flywheel having a flywheel annulus coupled to one of the rod and the threaded shaft. The flywheel is configured to rotate in proportion to axial acceleration of the rod relative to the threaded shaft in correspondence with actuation of the movable device by the actuator.

The present invention regards an elongated fluid actuator arrangement comprising a first and second cylinder housing (3, 5) extending in a longitudinal direction (X), respective housing (3, 5) encompasses a first respective a second piston body (7, 9). The respective piston body (7, 9) divides the respective cylinder housing (3, 5) in a first and second cylinder chamber (11, 13). The arrangement (1) is adapted for connection to a valve member means (15) of a fluid supply device (17). A piston rod member (19) extending through said respective first and second piston bodies (7, 9). The first piston device (7) comprises a piston rod engagement and disengagement means (29), which is adapted to engage or disengage the first piston device (7) to/from the piston rod member (19), wherein an engagement area (A2), defined by an engagement zone between the first piston body (7) and the piston rod member (19), is larger than a cross-sectional piston area (A1) of the first piston body (7).

The present invention regards an elongated fluid actuator arrangement comprising a first and second cylinder housing (3, 5) extending in a longitudinal direction (X), respective housing (3, 5) encompasses a first respective a second piston body (7, 9). The respective piston body (7, 9) divides the respective cylinder housing (3, 5) in a first and second cylinder chamber (11, 13). The arrangement (1) is adapted for connection to a valve member means (15) of a fluid supply device (17). A piston rod member (19) extending through said respective first and second piston bodies (7, 9). The first piston device (7) comprises a piston rod engagement and disengagement means (29), which is adapted to engage or disengage the first piston device (7) to/from the piston rod member (19), wherein an engagement area (A2), defined by an engagement zone between the first piston body (7) and the piston rod member (19), is larger than a cross-sectional piston area (A1) of the first piston body (7).

A shuttle valve connects a second flowpath and a drain flowpath when the hydraulic pressure in a first flowpath is greater than the hydraulic pressure in the second flowpath. The shuttle valve connects the first flowpath and the drain flowpath when the hydraulic pressure in a second flowpath is greater than the hydraulic pressure in the first flowpath. The ratio between the pressure receiving area of a first pressure section and the pressure receiving area of a second pressure section is the same as the ratio between the pressure receiving area of a first chamber side and the pressure receiving area of a second chamber side of a cylinder rod.

A shuttle valve connects a second flowpath and a drain flowpath when the hydraulic pressure in a first flowpath is greater than the hydraulic pressure in the second flowpath. The shuttle valve connects the first flowpath and the drain flowpath when the hydraulic pressure in a second flowpath is greater than the hydraulic pressure in the first flowpath. The ratio between the pressure receiving area of a first pressure section and the pressure receiving area of a second pressure section is the same as the ratio between the pressure receiving area of a first chamber side and the pressure receiving area of a second chamber side of a cylinder rod.

A hydraulic drive system raises and lowers an object by supplying and discharging operating oil to and from two ports of an actuator and includes a control device, first to fifth electromagnetic proportional control valves, first and second hydraulic pumps, a first and second control valve, and a lock valve. When a fourth pilot pressure is output, the second control valve causes the operating oil to be discharged from a first port in order to lower the object. The lock valve prevents the operating oil from being discharged from the first port by closing a path between the first port and the second control valve, and when a fifth pilot pressure is output from the fifth electromagnetic proportional control valve per an operating device, discharges the operating oil from the first port by opening the path between the first port and the second control valve, to lower the object.

A hydraulic drive system raises and lowers an object by supplying and discharging operating oil to and from two ports of an actuator and includes a control device, first to fifth electromagnetic proportional control valves, first and second hydraulic pumps, a first and second control valve, and a lock valve. When a fourth pilot pressure is output, the second control valve causes the operating oil to be discharged from a first port in order to lower the object. The lock valve prevents the operating oil from being discharged from the first port by closing a path between the first port and the second control valve, and when a fifth pilot pressure is output from the fifth electromagnetic proportional control valve per an operating device, discharges the operating oil from the first port by opening the path between the first port and the second control valve, to lower the object.