Abstract: Systems and methods described herein are intended for the reduction of grain bin entrapment. A method may include coupling at least a portion of a casing housing an auger to at least a portion of an inner sidewall of a grain bin. A method may include activating a power source of the auger to cause the auger to gather grain from a bottom portion of the grain bin and convey the grain to a top portion of the grain bin, thereby reducing an amount of the grain that is attached to the inner sidewall of the grain bin.

Abstract: A multi-stage float sorting device includes a first flotator float-sorting ores mixed with water based on a difference in density, and a second flotator provided with a column extending in a top-down direction, one side of which communicates with the first flotator to receive primary concentrates, and float-sorts the primary concentrates based on a difference in density to obtain secondary concentrates. The second flotator includes a washing water jetting section provided at a top of the column to jet washing water, a gas sparger provided at a bottom of the column to jet an inert gas, and an opening and closing section located between the washing water jetting section and the gas sparger to partition an inside of the column into upper and lower regions, and form an opening for rising secondary concentrates in the column according to a pressure state of the lower region.

Abstract: A mixer and method for mixing are provided. The mixer includes a housing including a fluid inlet, an additive inlet, and an outlet. The housing defines a mixing chamber in fluid communication with the fluid inlet, the additive inlet, and the outlet. The mixer also includes an impeller disposed in the mixing chamber. When rotated, the impeller pumps fluid through the fluid inlet. The mixer also includes a slinger disposed in the mixing chamber and configured to receive the fluid from the impeller and to receive an additive from the additive inlet. When rotated, the slinger slings the fluid and the additive radially outwards. The mixer further includes a flush line extending between the mixing chamber and the additive inlet. The flush line is receives, from the mixing chamber, a portion of the fluid pumped by the impeller and to deliver the portion of the fluid to the additive inlet.

Abstract: A sealed pressurized food dispensing system with self-cleaning features that can include a food processing apparatus that includes a cylinder having an inlet for receiving a food ingredient; a faceplate coupled to the cylinder, that defines a dispense bore and a bypass passage having a first open end; a blocking cap coupled to the faceplate to block the dispensing of product from within the cylinder; and a pump having an inlet fluidly coupled to a connection element and an outlet fluidly coupled to the inlet of the cylinder, where connection of the connection element to the source of cleaning fluid will result in the pumping of cleaning fluid into the food dispensing cylinder, though the cylinder into the blocking cap, and through the blocking cap into the bypass passage.

Abstract: A hot lather dispenser includes a compartment configured to receive a removable pod, a pump configured to receive liquid from the removeable pod during operation, a heater configured to head the liquid, an auger configured to combine the liquid with air to generate lather, and a nozzle configured to dispense the lather to a user.

Abstract: A system for preparing a polymeric mixture includes: a containment device configured to distribute dry polymeric materials; a receiving chamber in fluid communication with the containment device; a wetting bowl; a dispersing channel; and a mixing chamber connected to the dispersing channel. A method of preparing a polymeric mixture includes distributing water and dry polymeric materials through the various components of the system and mixing the materials with the mechanical mixing device.

Abstract: A fluid mixing system includes a flexible bag having a first end, an opposing second end, and an interior surface bounding a compartment. A first rotational assembly includes a first casing mounted to the first end of the flexible bag and a first hub rotatably mounted to the first casing. A second rotational assembly includes a second casing mounted to the second end of the flexible bag and a second hub rotatably mounted to the second casing. An elongated member has a first end coupled with the first hub and an opposing second end coupled with the second hub, the connector being flexible and having a uniform flexibility along its entire length. A first impeller is mounted to the connector.

Abstract: Equipment for processing food creams, which comprises a tub (11) housed in a removable manner inside a containment structure (2) and comprising a side wall (15), which is provided at the top with an access aperture (20) for loading the cream and is closed at the bottom by a bottom wall (17) provided with an exit aperture (22), through which the cream is dispensed outside the tub (11); cooling means (21) operatively associated with the tub (11) to absorb heat from the cream; an obturator (23) operatively connected to the bottom wall (17) of the tub (11) and movable between a closed position, in which it occludes the exit aperture (22) of the bottom wall (17), and an open position, in which it leaves the opening of the exit aperture (22) free in order to allow the cream to come out of the tub (11); a mixing body (30), rotatably housed inside the tub (11) and provided with a thrust surface (31) tilted and facing towards the bottom wall (17) of the tub (11); moving means (32) mechanically connected to the mixing

Abstract: An apparatus and methods of mixing materials in a silo that includes a mixing chamber (2) with an outlet (23) the bottom and an inlet hose (4) connected to an inlet opening at the top; a sieve (16) at the top of the mixing chamber above the inlet opening and below the outlet opening to prevent contact between a particulate mixing material and the top of the mixing chamber and to allow dust through; a pump system (18) to create a negative pressure region at the top of the mixing chamber; and an air manifold assembly (8), which includes an air pressure manifold (10) having an air nozzle (12) to introduce an air stream into the mixing chamber and an air manifold cover (14) to prevent contact between the particulate mixing material and the air pressure manifold, and to allow a particulate mixed product material to pass to the mixing chamber outlet.

Abstract: A drive unit for an endless conveyor, comprising a magnetic transmission and an electric motor connected to an input shaft of the magnetic transmission, where the magnetic transmission comprises a rotatable outer cylinder comprising a plurality of permanent magnets arranged as magnetic poles at the inner side of the outer cylinder, an intermediate cylindrical element comprising a plurality of ferromagnetic pole pieces, an inner cylinder comprising a plurality of permanent magnets arranged as magnetic poles at the outer side of the inner cylinder, where the outer side of the outer cylinder is configured with a drive surface adapted to interact with a conveyor belt or conveyor chain. The advantage of the invention is that a compact and efficient drive unit for a conveyor system is provided, which is provided with a contactless predefined slip.

Abstract: A system for preparing a polymeric mixture includes: a containment device configured to distribute dry polymeric materials; a receiving chamber in fluid communication with the containment device; a wetting bowl; a dispersing channel; and a mixing chamber connected to the dispersing channel. A method of preparing a polymeric mixture includes distributing water and dry polymeric materials through the various components of the system and mixing the materials with the mechanical mixing device.

Abstract: A confectionery composition comprising an edible shell having a filling therein. The filling comprises a fat system and has a solid fat content (SFC) of 35 to 65% at 0° C. and 1 to 8% at 30° C. In particular embodiments the fat system is prepared from palm oil midfraction. The filling is soft at low temperature so that it is palatable. However, it does not melt at ambient temperatures and therefore does not require refrigeration/freezing for storage or transport.

Abstract: A metering apparatus may be configured to control flow of material from a reservoir to control the amount of material applied, dispensed, and/or spread to a field while a vehicle traverses the field. The metering apparatus may include an auger portion located in an elevator channel to control the flow of material out of a reservoir opening of the reservoir.

Abstract: A method of introducing a first flow and a second flow into a process liquid flowing through a conduit including: injecting the first flow with an introduction liquid into the process liquid in transverse to a flow direction of the process liquid, wherein the injected first flow forms a mixing field comprising counter-rotating vortices in the process liquid; and injecting a second flow transverse to the flow direction of the process liquid and between the counter-rotating vortices.

Abstract: A hydraulic excavator includes a urea aqueous solution injection device, a urea aqueous solution tank, a pump, a first pipe, and a second pipe. The urea aqueous solution injection device is disposed in an engine compartment, and injects an aqueous solution of urea to clean exhaust gas. The urea aqueous solution tank stores the aqueous solution of urea. The pump draws up the aqueous solution of urea form the urea aqueous solution tank and supplies it to the urea aqueous solution injection device. The first pipe connects the reductant tank to the pump, and supplies the aqueous solution of urea from the reductant tank to the pump. The second pipe connects the pump to the reductant injection device, supplies the aqueous solution of urea from the pump to the reductant injection device, and has a smaller inside diameter than the first pipe.

Abstract: Disclosed is a mixing mechanism. The mixing mechanism includes an auger, a fluid handling portion, and at least one discharge hole. The auger configured to receive granular materials from a granular material source and capable of moving the granular material along a predetermined path. The fluid handling portion is coupled to a fluid supply source and has an inlet within an interior section of the auger. The size and positioning of the discharge hole (or holes) along the auger are specifically configured to allow for optimum mixing of the materials prior to being discharged.

Abstract: A manner of providing an improved fluid processing arrangement, and bioprocessing in particular, is adapted to agitate the fluid, and also simultaneously provide for the distribution of gas throughout the fluid in order to maintain desirable processing conditions (such as an increased level of dissolved oxygen, in the case of biological applications). In some embodiments, the mixing would be completed without necessitating the use of an external drive motor or the like, such as by using a fluid-driven mixer. Overall, use of the improved arrangement leads to a simplification of the fluid processing operation with improved results and a concomitant reduction in the expense associated with such use.

Abstract: A high impact pressure processor comprises of a piston. The piston comprises of a piston seal, a piston cap, a piston shaft, and a plurality of vent holes. The piston seal, located at an end of the piston shaft, seals out air from a container of a food processor or blender. This enables high impact pressure to be placed on the ingredient(s) in the container, thus creating smoother and thicker mixtures of ingredient(s). The plurality of vent holes allows air into container when needed, but are easily sealed off with the piston cap.

Abstract: Device for adding a fluid to a liquid, for example of gas and/or particles to liquid metal. A rotor is rotated immersed in the liquid, comprising a hollow rotational body 10 with a first inner annular wall 16 with at least one radial opening 18 from a central, cylindrical chamber 19 and with an opening directed downwards. The rotational body is carried by a generally vertical shaft 12 which is connected to a powering unit and which may be arranged to lift the rotational body out of, respectively lower it into the liquid. Outside the central annular wall 16 of the rotational body 10 a further annular wall 14 which forms an annular chamber 17 is arranged, which communicates with the central chamber through the one or more radial openings 18. Advantages are achieved by that the one or more of the radial openings 18 are arranged in the lower part of the inner annular wall 16 of the rotational body, in a area which projects down under the surrounding additional annular wall 14.

Abstract: A photobioreactor apparatus in which a reaction chamber contains a slurry of water, nutrients and photosynthetic organisms. The sidewall of the reaction chamber is constructed of translucent material, thereby permitting light to be conveyed into the slurry to promote photosynthesis. The interior of the reaction chamber is in fluid communication with a gas dispenser. A lift member is disposed in the reaction chamber and gas is introduced in the slurry beneath the lift member, thereby providing buoyancy to lift the lift member, thereby providing agitation and movement of the slurry within the photobioreactor and enhancing growth of photosynthetic organisms.

Abstract: A flexible pouch has a mixing apparatus, the mixer shaft of which is adjustable in length for use as a bioreactor for culturing microorganisms and cells.

Abstract: The improved rotor processor of the present invention includes a stator with a rotatable rotor defining a rotor chamber in which particles are circulated for coating or layering. A spray gun mounted to the stator adjacent the rotor directs liquid into the rotor chamber, while a powder feed system mounted in the stator adjacent the rotor directs dry powder into the rotor chamber. The spray gun and powder feed system are spaced apart circumferentially so as to define a spray zone and a separate powder zone through which the circulating particles repeatedly and sequentially pass. The powder feed system includes a feed screw conveyor, an eductor, and a flexible conduit for delivering micronized powders, such as polymers or glidants, to the rotor chamber.

Abstract: Systems and methods for automatically controlling conditions of a process are disclosed. In one example, a controller is programmed with a sequence of steps and parameters required to carry out a bioreactor process. A sensor system interacts with the bioreactor to receive information related to a condition of the bioreactor and/or receive a sample from the bioreactor, which it analyzes. The sensor system sends data signals related to the information and/or the sample to a controller, which determines a control signal based on the received information. The controller sends the control signal to the sensor system which, based on the control signal, performs an action that affects a condition of the bioreactor or affects the sensor system itself.

Abstract: A method of mixing including providing a flexible container which comprises at least two components, assembling the components from outside the flexible container to form a centrally disposed magnetic driven shaft with at least one impeller, whereby the integrity of the flexible container is maintained, filling the flexible container having the centrally disposed magnetic driven shaft with one or more ingredients of the contents to be mixed; engaging a magnetic element of the centrally disposed magnetic driven shaft with an external magnetic drive element; analyzing the contents of the flexible container using at least one sensor or a sampling line on the flexible container; and draining the contents of the flexible container through a drain port at the bottom of the flexible container.

Abstract: Systems and methods for automatically controlling conditions of a process are disclosed. In one example, a controller is programmed with a sequence of steps and parameters required to carry out a bioreactor process. The controller receives information related to a condition of the process over a first communication network, determines a control signal based on the received information and the programmed process, and sends the control signal over a second communication network to a benchtop utility tower. In one example, the utility tower can include transmitters for temperature, pH, and dissolved oxygen that send information related to a condition of the process to the controller over the first communication network, and an agitation system, a gas control system, a temperature control system and a pump control system that perform a control action based on the control signal affecting the process condition.

Abstract: A method and apparatus for injecting a gas into a liquid in which a rotating helical impeller within a draft tube submerged in the liquid creates a liquid flow within the draft tube. Gas bubbles are injected into the draft tube either above or below or alongside the helical impeller or in all three locations. The liquid is drawn into the draft tube with a superficial velocity greater than a substantially uniform terminal ascent velocity of the gas bubbles to allow entrainment of undissolved gas bubbles in the bulk liquid into the liquid being drawn into the draft tube. The gas bubbles are injected with a uniform diameter of between about 10.0 microns and about 1.0 millimeters. The small bubble size enhances the dissolution of the gas into the liquid and also allow the entrainment of the gas into the liquid being drawn into the draft tube.

Abstract: A reaction system and a reactor which comprises of two or more reaction cells wherein said cells are separated by inter cell conduits and having a means of causing agitation within the cells which does not require a mechanical connection of the agitating mechanism within the cell to a drive mechanism which is outside the cell.

Abstract: The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

Abstract: A method for hydrodesulfurization by forming a dispersion comprising hydrogen-containing gas bubbles with a mean diameter of less than 1 micron dispersed in a liquid phase comprising sulfur-containing compounds. Desulfurizing a liquid stream comprising sulfur-containing compounds by subjecting a fluid mixture comprising hydrogen-containing gas and the liquid to a shear rate greater than 20,000 s?1 to produce a dispersion of hydrogen in a continuous phase of the liquid and introducing the dispersion into a fixed bed hydrodesulfurization reactor from which a reactor product is removed. Systems of apparatus for hydrodesulfurization are also presented.

Abstract: A mixing apparatus including a kinetic energy source, a mixing tank, a pivot guide, and transfer shaft is used to drive a mixing paddle through a circular path within a tank without substantial shaft rotation. Sleeved and sleeveless mixing paddles are provided in combination with sealable mixing tanks. A volumetric compensation system responsive to tank wall deflection is used to maintain the internal volume of a mixing tank within predetermined limits. One mixing apparatus includes multiple mixing shafts and paddles coupled to at least one kinetic energy source. Methods for fabricating sleeved paddle-containing mixing apparatuses are further provided.

Abstract: Systems to store and agitate fuel can include a fuel storage tank including an air valve, and a fuel agitation system coupled to the fuel storage tank that can include an elongate fuel agitation member, a lumen, a plurality of valves extending from the elongate fuel agitation member, and an air passageway in fluid communication with the elongate fuel agitation member, where the air passageway is coupled to the first end of the elongate fuel agitation member by a rotational coupling located in the fuel storage tank that can be pneumatically actuated by air flow to rotate the elongate fuel agitation member as the air flow is introduced via the plurality of valves into the fuel storage tank, where the introduced air flow exits the fuel storage chamber out of the air valve.

Abstract: A vibrational mixer (1), in particular a single-path mixer for use in single-path bioreactors (4) with flexible walls, consisting of a mixer shaft (2) that can be set into longitudinal motions by a drive (8), with at least one mixing element (3), wherein at least one channel (13) is arranged in the mixer shaft with an opening to an interior reactor space (6).

Abstract: In a method of treating a liquid, a liquid to be treated is introduced into a space, a mechanical cavitation element acts upon the liquid while gas is supplied into the region of the surface of the cavitation element and introduces the gas into the liquid by moving the cavitation element, and sound waves are introduced directly into the liquid by at least one acoustic power transducer.

Abstract: A low-turbulent aspirating type aerator, introduced into a body of liquid, comprising of: a gas conveyance tube having a gas inlet end and a gas outlet end; a gas-liquid mixture chamber incorporating; an impeller affixed to a rotatable shaft, at the least one gas intake opening and at the least one gas-liquid discharge opening at or near bottom end of gas-liquid mixture chamber. Rotation of the impeller creates a low-pressure zone (vacuum) allowing gas conveyed via gas conveyance tube to come into contact with rotating impeller forming a gas-liquid mixture at the impeller interface wherein bubbles are formed. Gas-liquid mixture chamber confines gas bubbles thereby allowing the action of impeller and liquid shearing force to produce and discharge micro-sized gas bubbles of predominantly less than 0.85 millimeters.

Abstract: The invention relates to a device for stirring a liquid in a reactor and for injecting a gas into the said liquid in order to form a gas-liquid dispersion, comprising a) a drive device (1) positioned above the reactor, provided with a vertical output shaft (2) fitted at its lower end with at least one axial flow rotor (4) immersed in the liquid, b) means for introducing gas (3 and 7) above the axial flow rotor (4), c) a deflector (5) placed above the axial flow rotor (4) preventing the gas-liquid dispersion from rising, and d) a deflector (6) placed below the axial flow rotor (4) converting the axial flow of the said axial flow rotor into a radial flow. This device may be used in shallow basins.

Abstract: A device (1) for mixing powder (17) for a device for manufacturing a three-dimensional object comprises a stirring device (4) as well as a pressure-fluid-supply device for fluidizing the powder (17). A device (100) for manufacturing three-dimensional objects (503) is adapted to be connected to the device (100) for mixing powder (17) and it forms a system together with the device (1) for mixing powder (17).

Abstract: [OBJECT] It is an object to provide a stirring rotor and a stirring device capable of performing a stirring operation in a safe and efficient manner, irrespective of intended purposes. [SOLUTION] A stirring rotor 1 of the present invention comprises a rotor body 10 adapted to be rotated about a rotation axis C, an inlet port 12 provided in an outer surface of the rotor body 10, an outlet port 14 provided in the outer surface of the rotor body 10, and a flow passage 16 communicating the inlet port 12 with the outlet port 14. The inlet port 12 is provided at a position closer to the rotation axis C than the outlet port 14, and the outlet port 14 is provided at a position more outward in a centrifugal direction from the rotation C axis than the inlet port 12.

Abstract: A mixing device for synthetic leather to joint with a solid powder material includes a material mixing unit and a stirring and conveying unit. The material mixing unit includes a mixing body and two feeders. The mixing body is connected with the two feeders and has a mixing chamber therein which is intercommunicated with the two feeders. The stirring and conveying unit is connected with the material mixing unit and has a stirring and conveying chamber therein which is intercommunicated with a solid material container and the mixing chamber. Thereby, a solid powder material, a first material and a second material are respectively disposed in the solid material container and the feeders, and then guided into the mixing chamber to be well mixed for forming a mixture. The mixture is manufactured to form synthetic leather containing the solid powder material.

Abstract: The invention relates to a stirring arrangement having a rotating stirring body (2) for stirring fluids. The stirring body (2) has stirring blades (4) attached on a stirring body hub (3). The stirring body further includes a gas supply device (5) supplying a gas, such as air, for dispersing with the stirring body (2). The gas supply device (5) includes a distribution bushing (6) which rotates with the hub (3) of the stirring body (2) and has an interior for receiving the gas. The distribution bushing (6) and the interior thereof are in fluid communication with co-rotating outlet lines (7). Outlet openings of the outlet lines (7) are disposed in the immediate vicinity of the stirring blades (4) and within the volume swept by the stirring body (2) or in the immediate outflow zones, and discharge the gas at respective desired locations in the corresponding desired flow direction.

Abstract: A method of mixing liquid waste material in a digester tank by extending a supporting beam between opposing walls of the tank, securing a paddle to the supporting beam, fixturing the paddle for rotation about the supporting beam, securing a pair of inflatable air sacks to the paddle at opposing ends, and selectively inflating and deflating the sacks to force the paddle to tilt in cyclic motion thereby mixing the liquid waste containing bacteria, waste material, and oxygen uniformly throughout the digester tank.

Abstract: A mix head assembly for use in the manufacture of chemical mechanical polishing pad polishing layers is provided, wherein inclusions of entrained gas inclusion defects are minimized.

Abstract: A mixing container includes a flexible container, mixing elements and an upper bearing having a rigid flange. The flange is provided with an insertion passage that fluidically communicates with the inside space on one end and with the outside of the container on the other end. The flange is fixed in a rigid and sealing manner to the upper part of the wall of the container around an insertion opening, the insertion passage and the insertion opening communicating fluidically. The flange also supports, on the inside thereof, an upper bearing that is arranged inside, adjacent to the insertion passage, without preventing the fluidic communication between the insertion passage and the insertion opening. The mixing container is used to receive a biopharmaceutical content to be mixed.

Abstract: A stir system for stirring a liquid in a vial includes a top for at least partially closing the vial and a stirrer rotatable mounted in the top. The stirrer extends from the top into the vial and the stirrer is being connected with a magnet, which is rotatable during use by a rotating magnet field so as to rotate the stirrer in the vial. The system further includes a holder for holding the vial and a cover for covering the vial in the holder.

Abstract: A liquid containing chamber that supplies liquid to a liquid ejecting apparatus includes a first liquid container that is capable of containing the liquid and has a vertically long shape in a mounted position when mounted in the liquid ejecting apparatus, a first projection provided in the first liquid container and a first stirring member supported by the first projection, wherein when the first liquid container in the mounted position is divided into an upper container which is located above the first projection and a lower container which is located below the upper container, the lower container contains the liquid and the upper container contains the liquid and a predetermined amount of air.

Abstract: Systems and methods for automatically controlling conditions of a process are disclosed. In one example, a controller is programmed with a sequence of steps and parameters required to carry out a bioreactor process. The controller receives information related to a condition of the process over a first communication network, determines a control signal based on the received information and the programmed process, and sends the control signal over a second communication network to a benchtop utility tower. In one example, the utility tower can include transmitters for temperature, pH, and dissolved oxygen that send information related to a condition of the process to the controller over the first communication network, and an agitation system, a gas control system, a temperature control system and a pump control system that perform a control action based on the control signal affecting the process condition.

Abstract: A method for manufacturing chemical mechanical polishing pad polishing layers that minimizes entrained gas inclusion defects is provided. Also provided is a mix head assembly for use in the manufacture of chemical mechanical polishing pad polishing layers, wherein inclusions of entrained gas inclusion defects are minimized.

Abstract: A gas bubble agitated mixing system for viscous fluids comprising: a container (1) in which a viscous fluid (2) may be held; one or more gas pipes (6), each gas pipe having an outlet (8) arranged to introduce gas bubbles (9) into the base region of the container (1), said gas bubbles (9) being of a size suitable to agitate the viscous fluid (2). The system also comprises a moveable carrier arm (4) upon which said one or more gas pipe outlets (8) are mounted; and wherein the movement of the carrier arm (4) causes the position at which each outlet (8) introduces gas bubbles (9) into the container (1) to vary over time.

Abstract: A mixing vessel includes a flexible container, elements for mixing its contents, aeration elements, a drain/lower bearing port having a rigid flange provided with a drain passage, attached in a tight manner to the lower portion of the container wall, supporting a lower bearing that is adjacent to the drain passage. The vessel includes an extended element for dispensing aeration gas and is spaced essentially radially from the drain/bearing port; at least one tubular element for dispensing aeration gas extends from the extended dispensing element, in the inside space, along the inside surface of the lower portion and the side portion of the wall of the container and extends on the outside of the container from the upper portion; at least one mixing element is spaced essentially from the lower portion of the container wall, from the lower bearing, and from at least one extended element for dispensing aeration gas.

Abstract: A disposable mixing vessel comprising a flexible container, a centrally disposed shaft having first and second ends with one or more impellers thereon and a magnetic element associated with a first shaft end, a first flange adapted to rotatably engage the first shaft end and a second flange adapted to rotatably engage the second shaft end.

Abstract: Device for adding a fluid to a liquid, for example of gas and/or particles to liquid metal. A rotor is rotated immersed in the liquid, comprising a hollow rotational body 10 with a first inner annular wall 16 with at least one radial opening 18 from a central, cylindrical chamber 19 and with an opening directed downwards. The rotational body is carried by a generally vertical shaft 12 which is connected to a powering unit and which may be arranged to lift the rotational body out of respectively lower it into the liquid. Outside the central annular wall 16 of the rotational body 10 a further annular wall 14 which forms an annular chamber 17 is arranged, which communicates with the central chamber through the one or more radial openings 18. Advantages are achieved by that the one or more of the radial openings 18 are arranged in the lower part of the inner annular wall 16 of the rotational body, in a area which projects down under the surrounding additional annular wall 14.