Abstract:
A fully functional analyzing unit is included within the fluid-tight housing of a dialyzer which may be immersed in the medium to be analyzed. An opening in the housing is closed by a dialysis membrane. A channel defining body cooperates with the membrane to define a flow channel. The unit includes a carrier fluid reservoir and a carrier pump for generating a flow of carrier fluid through the flow channel. By dialysis via the membrane, the flow of carrier fluid is transformed into a flow of sample fluid which is received in a reaction channel. Reagent fluid from at least one reagent reservoir is delivered to the reaction channel by at least one reagent pump, and a detecting device is coupled to the reaction channel for detecting a reaction product originating from a reaction between the reagent fluid and the sample fluid and for generating a corresponding detection signal. Effluent from the reaction channel is received in a waste reservoir. Average volume flow in the reaction channel during operation is less than 100 .mu.l/min, allowing for at least 30 days of uninterrupted operation. The device is suitable for in situ real-time measurement of plant nutrient salts in process waters of waste water treatment plants.
Abstract:
A hydraulic piston engine driven by a lubricant-free, water-based pressure fluid, and comprising an enclosing housing and a piston-connected drive shaft supported by radial journal bearings in bearing bushings. One of the sliding surfaces of the radial journal bearing comprises a recess with a bearing-supporting hydrostatic pressure fluid pocket. The center of the recess is displaced by an angle (.alpha.) in the direction against the direction of rotation of the drive shaft, seen in relation to the geometrical, radial mean point in the high-load area for transmission of the piston forces to the bearing surface via the drive shaft. Hereby a particularly reliable piston motor of the type indicated is provided.
Abstract:
A hydraulic axial piston machine is disclosed, having a cylinder drum which is mounted for rotation relative to a housing (1), with a bearing (3) having a slide face (4) being arranged between the circumference of the cylinder drum and the housing (1). It is desired that such a machine shall be capable of operating also with fluids that are not such good lubricants as hydraulic oil. For that purpose the slide face (4) is formed by a friction-reducing plastics material and has at least one recess (5, 6, 7) communicating with at least one end edge of the slide face (4).
Abstract:
A measuring section for an electromagnetic flowmeter is provided having a metallic measuring tube made of a non-magnetic material, a set of magnetic coils for generating a magnetic field in a direction substantially at fight angles to the direction of flow, an electrode arrangement which is arranged substantially at fight angles to the direction of the magnetic field and substantially at right angles to the direction of flow, and an electrical insulator on the inside of the measuring tube, and also a method for the manufacture of this measuring section. Here, it is desirable for manufacture to be carried out with a relatively high degree of reliability. For that purpose, the insulator is constituted by a surface layer of metal oxide or metal nitride having a thickness of more than 10 .mu.m an on the inside of the measuring tube. The inside of the measuring tube can be oxidized or nitrogenized for that purpose and a metal oxide or a metal nitride is deposited on the resulting oxide or nitride layer.
Abstract:
A controlled proportional valve is provided, with a main slide valve section (4) containing a main slide valve, which section controls a flow of fluid between a pump connection (P) connected to a pump (2) and a tank connection (T) connected to a tank (6) and two work connections connected to a load (5) and which generates a load-sensing signal (LS.sub.INT) in dependence on the pressures at the work connections (A, B), and with a compensating slide valve section (3) which controls the pressure across the main slide valve section (4) in dependence on the load-sensing signal (LS.sub.INT). It is desirable to achieve a more rapid response time in a proportional valve of that kind, wherein the control means should be capable of being retrofitted to existing proportional valves. To that end, a control arrangement (10) which controls the pressure of the load-sensing signal (LS.sub.INT) to influence the actual volume flow and/or the actual pressure in the work connections (A, B) is provided.
Abstract:
A hydraulic machine is disclosed, with an annular gear with internal teeth and, eccentrically mounted in the annular gear, a gearwheel with external teeth which engage with the internal teeth, the internal teeth comprising one more tooth than the external teeth and the contour of the external teeth being formed by an envelope of a system of generating circles, the midpoints of which lie on a trochoid which, as a rolling circle rolls without slipping on a base circle, can be generated by the movement of a point lying on a radial ray of the rolling circle co-rotating with the rolling circle. A method of producing the contour of a rear wheel of such a machine is also disclosed. In such a machine it is desirable to realize a satisfactory inner seal and low Hertzian stresses. To that end, the spacing of the point from the midpoint of the rolling circle is larger than the radius of the rolling circle. The tooth form can then be formed by the end points of a system of line segments which are located at right angles to the trochoid and are the same length as the radii of the generating circles, wherein the trochoid encloses a closed inner face and separates it from an outer face and several intermediate faces, and the line segments are, arranged only in the inner face.
Abstract:
A mass flowmeter has a flow-through channel (2) and as its measuring section (10) a thin strip (3) which at one end has an oscillation generator generating waves travelling along the measuring section (10) and at the other end has an energy converter (8, 9) acting as oscillation detector for these travelling waves. An evaluating circuit (11) determines the mass flow on the basis of the travelling speeds which are different in and against the direction of flow (X). In particular, only one measuring section (10) is provided, the energy converters (8, 9) of which are operable alternately as oscillation generator and oscillation detector. In this manner, meters of relatively short length and high accuracy can be made.
Abstract:
A hydraulic axial piston machine is disclosed, with a cylinder drum (2), which has at least one cylinder (3), in which a piston (6) is mounted so as to be axially displaceable, and with a control counter-plate (11 ) which, on rotation of the cylinder drum (2) and the control counter-plate (11 ) relative to one another, connects the cylinder (3) in dependence upon its position with a fluid inlet (14) and a fluid outlet (15). With a machine of that kind, it is desirable to improve balancing out of the forces necessary for effecting a seal between the cylinder drum (3) and the control counter-plate (11). For that purpose, between the cylinder drum (2) and the control counter-plate (11 ) there is arranged a pressure plate (17) which engages the cylinder drum (2) via the intermediary of a spring element (21), the pressure plate (17) having a through-opening (20) associated with the cylinder (3), which through-opening is connected to the cylinder (3) in a fluid-tight manner.
Abstract:
An axial piston machine (1) is described, having a cylinder body (2) that is rotatable relative to a wobble plate (3) and in which several pistons (6) are arranged so as to be axially displaceable, the pistons being supported on a sliding-contact face (4) of the wobble plate 930 by means of slider shoes (9) articulated at the free ends of the pistons, wherein a pressure element (13) holding the slider shoes (9) on the sliding-contact face (4) is provided. It is desirable to reduce internal leakage in an axial piston machine of that kind. For that purpose, a wave spring element (16) is provided between each slider shoe (9) and the pressure element (13).