| 摘要 |
A linear actuator with a reversible electric motor (3,11,26,27,34), which over a transmission (4,12,24,25,35) drives a non-self locking spindle (5,14,22,23,36), by which a tube-shaped positioning element can be moved axially, in that it with one end is connected to a spindle nut (6,15) on a spindle (5,14,22,23,36). The actuator comprises a quick release (9,13) for releasing the tube-shaped positioning element (7,16,28,29,37) from the electric motor (3,11,26,27,34) and the part of the transmission (4,12,24,25,35) that lies from the motor (3,11,26,27,34) to the quick release (9,13) such that the spindle (5,14,22,23,36) is set to rotate by the load on the tube-shaped positioning element (7,16,28,29,37). The actuator further comprises braking means for controlling the speed of the tube-shaped positioning element (7,16,28,29,37) during the outer load, when the quick release (9,13) is activated. The braking means consists of a centrifugal brake (38,60), by which it is possible to provide a construction where the lowering speed is self-controlled when the quick release (9,13) is activated. |
| 主权项 |
1. A linear actuator which comprises:
a non-self-locking spindle, a spindle nut mounted on the spindle to move axially along the spindle with rotation of the spindle, a non-rotating tube-shaped positioning element associated with the spindle nut to move axially along the spindle with the spindle nut, a reversible electric motor for rotating the spindle, said electric motor including a shaft with a worm, a quick release mechanism for disconnecting the spindle from the electric motor when the quick release mechanism is activated, and braking means for controlling a speed of movement of the positioning element along the spindle under an external load after the quick release mechanism has been activated, said braking means including a centrifugal brake connected to the spindle and a gearing mechanism between the centrifugal brake and the spindle for increasing revolutions of the centrifugal brake, said gearing mechanism comprising a planetary gear comprising a sun wheel, a planetary wheel holder and an outer toothed rim with outer worm wheel toothing to which the worm is engaged, the spindle being connected to the planetary wheel holder and the sun wheel is connected to the centrifugal brake and the quick release mechanism. |
