Abstract:
The invention refers to coupling mechanism and a linear actuator incorporating such a mechanism for releasably interconnecting first and second mechanical members (1, 2), longitudinally movable relative to each other, a first one of said mechanical members (1) pivotably supporting an end (F) of a first link of a knee link mechanism (3), also incorporating a second link member (3b), which first and second link members are pivotally connected to another in a knee joint (E), a control rod (4) pivotally connected to said knee joint (E), the end (D) of the second link member (3b) remote from the knee joint (E) being connected to a hook arm (5), the opposite end of which is pivotally supported at a support point (B) stationary positioned relative to said first mechanical member (1), said hook arm (5) having a hook (5a) facing said second mechanical member and being in mechanical engagement (A) with a shoulder (6, 6') on said second mechanical member (2) as long as the said knee joint (E) is kept in a substantially stretched position by said control rod (4), which is kept stationary under influence of a holding force exerted in connection to said first mechanical member (1), but which is arranged to displace the knee joint (E), thus that the hook (5a) of the hook arm (5) is pulled out from its engagement with the shoulder on the second mechanical member, when the holding force expires or drops under a threshold value.
Abstract:
The invention concerns a safety device (1) for an actuator comprising a connection means (2) allowing a connection to a releasable holding means (5). The connection means (2) is fixed via a sacrificing means (3) to a supporting means (4), and a resilient means (7) is acting between the supporting means (4) and a supporting portion (8). An extension means (9) is fixed to the supporting means (4) via the connection means (2). The sacrificing means (3) has a mechanical strength such that the sacrificing means (3) breaks when subjected to a force exceeding a predetermined force, such that the extension means is no longer fixed to the supporting means and that a re-connection of the supporting means (4) and the releasable holding means (5) is made impossible. The predetermined force is lower than the mechanical strength of the extension means (9) and the supporting means (4). A linear actuator (13) comprising the safety device (1) is also provided.
Abstract:
A device for changing a pitch of a blade of an impeller/propeller is disclosed. It comprises at least one linear actuator. A first bearing is mounted to a non rotary mechanical element with the first portion, and a second bearing is mounted to the second portion, allowing a relative axial movement between the first bearing and second bearing. The first bearing is mounted between a supporting structure of the rotor shaft and the non rotary mechanical element, allowing a relative rotation between the supporting structure and the at least one linear actuator. The second bearing is mounted between the second portion and a lever means having a rotary point at the supporting structure. When operating the at least one linear actuator, the second portion is moved axially, leading to an angular movement of the lever means causing a change of the pitch of a blade, and when operating the at least one linear actuator, a force is generated that acts upon the non rotary element, so that the rotor shaft is unaffected by the force. Also, a fan comprising the device is disclosed.
Abstract:
The invention concerns a valve actuator (1) comprising a housing (2) and a nut and screw arrangement. A first portion (5) of the nut and screw arrangement is operated by an electric motor (7), which is fixed to the housing (2). A means (8) is in contact with a second portion (6) of the nut and screw arrangement, and a resilient means (9) is acting between the means (8) and the housing (2). A relative rotation between the threaded nut (3) and the threaded screw (4) leads to a translation of the means (8) and an energizing or de-energizing of the resilient means (9). A locking means (10) locks the resilient means (9) in an energized state by locking the relative rotation of the nut and screw arrangement. When the locking means (10) are released, the resilient means (9), when de-energizing, acts on the means (8), leading to a translation of the means (8).
Abstract:
A device (1) for canting a keel arrangement (9) about a longitudinal axis of a sailing vessel is disclosed. It comprises a screw and nut arrangement (3), comprising a threaded nut (5) receiving a threaded screw (7). The screw and nut arrangement (3) is fixable to the keel arrangement (9) and to a fixed element (11) of the sailing vessel essentially perpendicularly to the longitudinal axis. A relative rotation between the threaded screw (7) and the threaded nut (5) is responsive for canting the keel arrangement (9) in relation to the sailing vessel. A mechanical rolling means (13) is in contact with the threaded screw (7) and the threaded nut (5). Also disclosed is a system (51) for canting a keel arrangement (9) about a longitudinal axis of a sailing vessel, comprising two devices (1).