Abstract: A device for performing an action on a surface comprises at least one movably arranged functional body (21, 22), driving means for driving the functional body (21, 22), main safety means for decoupling the driving means from the functional body (21, 22) when a load exerted by the functional body (21, 22) in the direction of the driving means under the influence of resistance forces experienced by the functional body (21, 22) exceeds a predetermined maximum value, and additional safety means (40) which are movably arranged in the vicinity of the functional body (21, 22), and which are capable of exerting loads on the main safety means to different extents in different positions, at a side of the main safety means associated with the functional body (21, 22). The additional safety means may comprise a bar (40) having a non-circular cross-sectional area, which is rotatable about its longitudinal axis (41).

Abstract: A device (1) comprises filtering means (30) for removing particles from a fluid, which have a particle collecting face (31) for collecting particles during use of the device (1), and a chamber (10) in which a fluid is present and in which the filtering means (30) are arranged. An inlet (11) of the chamber (10) comprises a spouting part (20) which serves for spouting the fluid to be filtered in a direction towards the particle collecting face (31) of the filtering means (30). An arrangement of the spouting part (20) and the particle collecting face (31) with respect to each other is adapted to generate, during operation of the device (1), a rotating flow pattern in the fluid that is present in the chamber (10) under the influence of the flow of the fluid to be filtered, whereby particles can be blown away from the particle collecting face (31).

Abstract: A device for performing an action on a surface comprises at least one movably arranged functional body (21, 22), driving means for driving the functional body (21, 22), main safety means for decoupling the driving means from the functional body (21, 22) when a load exerted by the functional body (21, 22) in the direction of the driving means under the influence of resistance forces experienced by the functional body (21, 22) exceeds a predetermined maximum value, and additional safety means (40) which are movably arranged in the vicinity of the functional body (21, 22), and which are capable of exerting loads on the main safety means to different extents in different positions, at a side of the main safety means associated with the functional body (21, 22). The additional safety means may comprise a bar (40) having a non-circular cross-sectional area, which is rotatable about its longitudinal axis (41).

Abstract: A device (1) comprises filtering means (30) for removing particles from a fluid, which have a particle collecting face (31) for collecting particles during use of the device (1), and a chamber (10) in which a fluid is present and in which the filtering means (30) are arranged. An inlet (11) of the chamber (10) comprises a spouting part (20) which serves for spouting the fluid to be filtered in a direction towards the particle collecting face (31) of the filtering means (30). An arrangement of the spouting part (20) and the particle collecting face (31) with respect to each other is adapted to generate, during operation of the device (1), a rotating flow pattern in the fluid that is present in the chamber (10) under the influence of the flow of the fluid to be filtered, whereby particles can be blown away from the particle collecting face (31).

Abstract: A unit (2) for pumping air containing particles (5) and separating the particles (5) from the air comprises a housing (10) having a space (20) for receiving and storing the particles (5), and an air pumping device (30) being arranged inside the housing (10) and comprising a basic fan (31) intended for pumping air out of the particle storage space (20), and another fan (32) intended for separating the particles (5) from the air. A gap (22) is present between the fan arrangement of the air pumping device (30) and the housing (10), and in order to avoid a flow of air containing particles (5) through the gap (22), at least a major portion of the basic fan (31) is uncovered, so that a relatively strong pumping action on the basis of an interaction of an outer surface of the basic fan (31) with a stationary wall is avoided.