Abstract: A backflush filter device for filter elements (22) is incorporated in a filter housing (10)having a filter inlet (18) and an outlet (20) for the liquid to be filtered. The filter elements (22) permit flow in both directions for a filtration, or backflush. One filter element (22) may be performing a filtration and, simultaneously, at least one other filter element (22) may be backflushed to clean its effective filtration surface. To assist the backflushing, a vacuum device (42) is provided. The vacuum device generates a vacuum at the filter element (22) to be backflushed. The efficacy of the ongoing backflush is increased to be able to remove even the toughest contaminants. The cleaning process uses little energy and occurs in a defined manner, such that the backflush volumes may be both specified and minimized.

Abstract: A method monitors the gas prefill pressure in hydraulic accumulators. After the pressure supply to the oil side of the accumulator has been interrupted and the contents of the tank have been emptied, the current gas temperature and the current gas pressure are determined, once the temperature has equalized. The data relating to the gas temperature and pressure is telemetrically transmitted to an evaluation unit, which is spatially located at a distance, to calculate an actual value of the gas prefill pressure which corresponds to a reference temperature.

Abstract: An arrangement monitors the useful properties of pressure fluids (5) in fluid-technical installations. A plurality of measured variables, each representing a useful property of the pressure fluid, are determined by a plurality of sensors (13, 15, 17) which are combined with a pump (11) to form a structural unit which can be build into a tank (3) containing the pressure fluid. The sensors (13, 15, 17) are hydraulically connected in series with the pump (11).

Abstract: A shutoff valve has a movable flap member rotatably mounted in a valve housing. The valve housing has concentric, spherically-shaped sealing surface zones which cooperate with an edge of the flap member. The housing also has two coaxial couplings and one perpendicular coupling. By rotation of the flap member, flow can be directed from the perpendicular coupling to either of the two coaxial couplings. The three couplings have axes which meet at a common point. The rotational axis of the flap member passes through that common point. The two concentric spherical sealing surface zones are separated by a 90.degree. rotation of the flap member.

Abstract: A switching valve for the selective connection of each of a plurality of measuring locations with a manometer has a first valve body mechanically connected to the manometer and a second valve body rotatable with respect to the manometer, the second body having a radial control bore connected constantly with the measuring bore of the manometer. In order to attain tight closure between the two valves without the use of seat valves, the second valve has a spherical zone into which opens a control bore. In the other part are a plurality of packing bodies, the number of which corresponds to the number of measuring locations, each of the packing bodies having a central bore in a plane perpendicular to the axis of the first valve, each packing body have an annular sealing surface which is in constant contact with the spherical zone. A chamber including the spherical zone can be connected outside of the packing surfaces to a vent tank.

Abstract: An apparatus for clamping two side-by-side pipes together comprising two recessed holding bodies receiving the pipes therein, two clamping elements having the holding bodies therebetween and a screw interconnecting these four members. Interlocking projections and indentations on one of the clamping elements and its adjacent holding body prevent relative rotation during tightening of the screw.

Abstract: A pump bracket includes a two-part bracket housing with a heat exchanger mounted therein through which air can flow, the bracket being attached to, and between a motor and a pump. The shafts of the motor and pump are coupled together and a fan blower wheel is mounted on the motor shaft. A blower casing controls air flow to the suction side of the blower wheel. In one embodiment the casing channels incoming air from a portion of the exchanger to the suction side of the wheel which blows air out through the rest of the exchanger. In another embodiment air is drawn in through openings in the housing, directed to the suction side by the casing and blown out through the exchanger.