Abstract: Fan (16), in particular for an aircraft cooling unit, having a wheel (128) comprising a hub (138) and an annular array of blades (140), a shaft assembly (136) for driving the wheel about an axis (A), and fusible means for connecting the hub of the wheel to the shaft assembly, said fusible connecting means comprising a first mounting sleeve through which the shaft assembly extends and which is surrounded by the hub, and fusible safety elements (174) which extend parallel to the axis (A) and are configured to break and to disengage the wheel from the shaft assembly when said wheel rotates and a driving torque of the wheel transmitted by the shaft assembly exceeds a certain threshold, characterised in that the connecting means comprise a second wearing sleeve (143) which is inserted between the first sleeve and the hub and through which the fusible elements extend, the second sleeve being made of a material which is different from that of the first sleeve and subject to wear by friction and/or by heating if the

Abstract: The invention relates to a fan, in particular for an aircraft cooling unit, comprising a wheel (128) and a shaft line (136) for driving the wheel about an axis (A), said wheel including a hub (138) supporting an annular row of blades (140), and means (142) for connection to said shaft line that are housed inside said hub. The fan is characterized in that the connection means include at least one meltable safety element (158) designed to be broken and to rotationally disengage at least a portion of the connection means from the shaft line when a torque for driving the wheel that is transmitted by the shaft line exceeds a specific threshold.

Abstract: Fan (16), in particular for an aircraft cooling unit, having a wheel (128) comprising a hub (138) and an annular array of blades (140), a shaft assembly (136) for driving the wheel about an axis (A), and fusible means for connecting the hub of the wheel to the shaft assembly, said fusible connecting means comprising a first mounting sleeve through which the shaft assembly extends and which is surrounded by the hub, and fusible safety elements (174) which extend parallel to the axis (A) and are configured to break and to disengage the wheel from the shaft assembly when said wheel rotates and a driving torque of the wheel transmitted by the shaft assembly exceeds a certain threshold, characterised in that the connecting means comprise a second wearing sleeve (143) which is inserted between the first sleeve and the hub and through which the fusible elements extend, the second sleeve being made of a material which is different from that of the first sleeve and subject to wear by friction and/or by heating if the

Abstract: The invention relates to a fan, in particular for an aircraft cooling unit, comprising a wheel (128) and a shaft line (136) for driving the wheel about an axis (A), said wheel including a hub (138) supporting an annular row of blades (140), and means (142) for connection to said shaft line that are housed inside said hub. The fan is characterized in that the connection means include at least one meltable safety element (158) designed to be broken and to rotationally disengage at least a portion of the connection means from the shaft line when a torque for driving the wheel that is transmitted by the shaft line exceeds a specific threshold.

Abstract: The new agent, based on glycols and water and having crosslinked acrylic polymers as thickener and also customary corrosion inhibitors, surfactants belonging to the group of alkali metal alkylarylsulfonates and neutralizing agent to adjust the pH to a basic value, contains, as the thickener, two selected crosslinked acrylic polymers in a specific ratio by weight to one another, namely a selected crosslinked acrylic acid or alkali metal acrylate homopolymer and a selected crosslinked acrylic acid/acrylamide or alkali metal acrylate/acrylamide copolymer in a ratio by weight of 2 to 10:1 and, as the neutralizing agent, three alkaline compounds, each in a selected amount, namely ammonia, monoethanolamine, diethanolamine and/or triethanolamine as the first alkaline compound, potassium hydroxide as the second alkaline compound and a further alkali metal hydroxide as the third alkaline compound.

Abstract: A liquid agent for de-icing and protecting against icing-up is described, by means of which it is possible, in particular, to free the metal surface of aircraft rapidly and completely from ice, hoar-frost, snow and the like, and to protect the surface against further build-up for a relatively long period. The agent is essentially composed of several components, namely of (a) glycols, (b) water, (c) thickeners, (d) substances insoluble in water, (e) surface-active agents, (f) corrosion inhibitors and (g) alkaline compounds, in very specific quantities in each case, the quantity of the components (a) and (b) being at least 94%, relative to the total weight of the agent. Its pH value is 7.5 to 10.

Abstract: Brake fluids and operating fluids for central hydraulic installations in motor vehicles having an excellent temperature / viscosity behavior and good lubricating properties are obtained by the admixture to conventional polyethylene glycol alkyl ether-based fluids of alkyl polyethylene glycol-t-butyl ethers of the formula ##STR1## in which R is a straight or branched chain alkyl radical having from 1 to 4 carbon atoms and n is an integer of from 2 to 10, preferably from 2 to 5. Mixture of the ethers may be employed.