(57) Abstract:Usage: cleaning the contact electrodes of the sensor from contamination during operation in liquid media without removing the sensor and leaking joints. The inventive electrode sensor placed in the insulator, has an outer screw surface in contact with the working environment. This surface is associated with the internal helical surface of the sleeve is fixed in the insulator. The sleeve is made a longitudinal section and a transverse annular groove on the outer surface. In the groove of the installed spring washer. The electrode sleeve and washer are made of corrosion-resistant metal. Metal bushings are harder than the metal of the electrode. 2 C.p. f-crystals, 1 Il. The invention relates to izmeritelnaya technique, namely the capacitance and conductivity measurement can be used to measure the interface, continuity of liquids in the petroleum, chemical, food, pharmaceutical, microbiological and other industries, as well as in agriculture and are able to operate in liquid environments in which on the surfaces of the electrodes stick and OSA the developers and users of these funds.Known level switch containing the electrode with the measuring relay, indicator and oscillator  Since the cleaning of the electrode is carried out by means of vibration at the resonant frequency, this device is not designed for operation in liquid flows, creates turbulent eddies and leading to the disruption of the resonance oscillations of the electrodes. In addition, failure of the oscillations and termination cleanup will take place at the deposition, sticking clot of dirt.Known purification method sensitive element uravneniya on author.St. USSR N 708163, CL G 01 F 23/26, in which cleaning is carried out by compressed air attached to the electrode elastic shell.The disadvantages of the device that implements this method of treatment should be attributed to the low durability of the sheath material, solinet in the implementation of pressurized compressed air under the membrane, the need to have a source of compressed air. In addition, the measurement tool in this case cannot be conductivity type and is not suitable for use in conductive liquid environments.A device for measuring the dielectric parameters of liquids by the author. St. USSR N 748220, CL G 01 N 27/22, adirenne with mechanism for reciprocating movement and which is simultaneously the piston and purifier of electrodes. This device works only in the pipelines and are not suitable for measuring fluid levels.Famous adopted for the prototype, the electric-contact level sensor containing fluid in the form of a cylindrical pin and a stationary ring-shaped electrodes  the Movable electrode is connected with the drive of a reciprocating movement. Cleaning of the movable and fixed electrodes are knife edges of the rotating blades, oriented along the electrodes.The disadvantages of the design of this sensor include the following:
when performing blade entirely of dielectric their knife edges will have a low resistance to wear and require periodic replacement blades;
when doing knife edges of the metal is one of the weak structural links of the sensor will be attaching them to the blades, taking into account the actual dimensions and weight of the latter, which would also affect the reliability and durability of the sensor;
simultaneous rotation of the blades and reciprocating movement of the electrode is carried out from the shared drive motor that generates during operation difficulties in maintaining both the maximum is Aya, bulky design, the large size and weight;
the design of the sensor is not designed for operation in liquid flows.The invention is directed to the development of malogabaritnih sensor simple design that provides a reliable cleaning of the electrodes.The essence of the invention lies in the fact that contact the sensor containing at least one movable electrode, placed in the isolator, the portion of the outer surface of the electrode which is in contact with the operating environment are made in the form of a helical surface that interacts with the response, mating internal helical surface of the bushing mounted stationary in the insulator. The sleeve is made a longitudinal section and a transverse annular groove on the outer surface, in which the spring washer. The movable electrode, the sleeve and the spring washer is made of corrosion-resistant metal, and the metal sleeve is greater than that of the metal electrode hardness.The drawing shows the proposed sensor.The sensor includes a housing 1, which has an insulator 2, for example, PTFE, in the body which, in the part that is in contact with the working environment, flush the pipeline section and the outer transverse annular groove, which is equipped with spring washer 4. The sleeve is fixed in the body of the insulator with three screws 5 without heads set flush with the outer surface of the insulator. The electrode 6 of the sensor on-site cut mating metric thread and he is screwed into the sleeve with a protrusion at its end. The reciprocating movement of the electrode is limited to one side ledge in prison, with another partition in the housing, and the length of the move is determined by the length of the work area. Case, the electrode, bushing, washer, and screws are made of corrosion-resistant metal and the hardness of the metal sleeve is higher than the hardness of the metal electrode. Seal joints between the sensor housing and accommodation, between the casing and the insulator between the insulator and the electrode is provided with a rubber ring 7.Cleaning the working electrode piece is done when it is rotating clockwise and counterclockwise, causing the reciprocating movement of the working part of the electrode relative to the sleeve. Reliable and quality cleaning is done by friction forces that occur when moving spiral surfaces relative to each other. Thus the longitudinal slit in the sleeve and spring washer constantly oblasti when the movements of the piston area of the electrode.The essential features of the invention:
the working area of the electrode in the form of an outer screw surface;
placing the working side of the electrode fixedly mounted in the insulator sleeve having mating internal screw surface;
the presence in the sleeve longitudinal section and a transverse outer annular groove in which is placed a spring washer;
the manufacture of the electrode, bushings and washers made of corrosion-resistant metal;
manufacturer of bushings made from metal with a greater degree of hardness than the metal of the electrode.Thus, the proposed sensor involves an inventive step. i.e. set of features leads to a new device that provides the desired technical effect cleaning of the working part of the electrode from contamination that extends the functionality of the sensor when operating in liquid environments.The sensor is provided by an Autonomous electrode cleaning without dismantling and leaking joints. The proposed sensor is easy to manufacture and maintain in operation, reliable in performance, has small dimensions and weight, able to work under pressure working environment to 2.0 MPa (20 kgf/cm
FIELD: measuring engineering.
SUBSTANCE: device comprises fuel level indicator and rheostat pickup made of an analogue-digital converter with the balance input. The three-position switch is connected with the lever indicator. The device additionally has three resistive dividers, voltage stabilizer, and shunting resistor made of a 0.003-0.006-Om resistor. The rheostat level pickup is mounted inside the fuel tank vertically, and its linear horizontal size at this level is directly proportional to the area of the tank section in the horizontal plane at this level.
EFFECT: expanded functional capabilities.
FIELD: measuring engineering.
SUBSTANCE: method comprises pressing unit reinforced by electrodes with simultaneous forming of insulator between the electrodes. The space that is defined by surfaces of the electrodes is filled with casting plastic mass. The pressure tightness is provided by tightening the insulator with electrodes by means of a nut.
EFFECT: enhanced reliability.
FIELD: the invention refers to measuring technique and may be used for controlling bulk and liquid materials.
SUBSTANCE: the oscillating indicator of a level has a sensible element( a probe) 1 connected with an anchor 2, a driving arrangement 4 in the shape of a coil with a ferromagnetic core and also a sensor 5 of the displacements of the anchor, a drive-pulse generator 6 and an amplifier 7 and a relay block 9 successively connected. The amplifier is spanned with a regulated negative feedback fulfilled in the shape of a resistor 8. The sensor 5 of the displacements of the anchor may be fulfilled in the shape of a coil with a ferromagnetic core. At that the section of the anchor 2 between the coils is fulfilled out of non-magnetic material that prevents electromagnetic connection between the coils providing protection from high frequency oscillations in the system anchor-coil-amplifier.
EFFECT: allows to control the levels of the bulk and liquid materials being present in aggressive mediums, under pressure,( discharge)and at temperature till 200 degrees.
FIELD: instrument engineering.
SUBSTANCE: level meter sensor comprises hollow rigid base with the port in its bottom end, diaphragm, strain gage converter with box, flexible spacer arranged over periphery of the box, and tube whose one end is mounted pressure-tightly in the port of the support and the other end is connected to the space of the box. The diaphragm is made of a rigid material and mounted on the flexible spacer for permitting cooperation with the strain gage converter.
EFFECT: enhanced reliability and simplified structure.
FIELD: the invention refers to the field of instrument making and designed for control of the level of dielectric and current conducting liquids in hydraulic systems (fuel, freezing, accumulative etc) for example the level of oil or cooling agent in transport vehicles.
SUBSTANCE: the liquid level meter has a two-electrode capacitance sensor with an external 10 and interior 11 electrodes electrically connected with an electronic scheme having a stabilized source of power supply, an amplifier, a generator and a trigger. According to the first variant the capacitance sensor is fulfilled in the shape of a coaxial condenser "C". The interior electrode 11 of the sensor is fulfilled tubular and is mounted inside a fluoroplastic probing rod 12. The interior electrode 11 is connected to the input of a phase comparator which is additionally introduced in the scheme and whose output is connected with input of the trigger and the output of the last is provided with a line of delay and has two outputs - direct and inverse connected with a transistor key fulfilled with possibility of fulfillment of an operation "switched on" or "switched off". At that the electronic scheme is fulfilled on a digital integrated microchip. According to the second variant the interior electrode 11 of the coaxial condenser "C" is fulfilled tubular and is additionally provided with a protective shield 22. The shield 22 is fulfilled in the shape of a spiral spring out of bronze and electrically connected with the external electrode - the body 10 of the coaxial condenser "C".
EFFECT: increases sensitiveness and accuracy of measuring of the level of liquid.
6 cl, 4 dwg
FIELD: invention refers to control-measuring technique and is assigned for control and signaling about border of interface between mediums petroleum product-water in installations for purification water from petroleum products or watered petroleum products from water.
SUBSTANCE: sensor has flange, three electrodes with sleeves on their low ends filled with fresh water, moreover two of them are covered with dielectric insulation. Electrodes with sleeves are located inside tube of protective screen and are fastened in flange with aid of stuffing boxes-insulators. Screen in upper part has diaphragm ring with openings along circumference coinciding with openings in screen forming swinging compensator and is fastened to flange with aid of screws. Electrodes of sensor together with sleeves and electronic part form oscillating contour going in resonance at presence in space between electrodes of electric conductive medium (water) with following triggering of executive elements and at presence of water between electrodes of petroleum product resonance of contour stops.
EFFECT: increases reliability of work of sensor.
2 cl, 1 dwg
FIELD: physics, measurement.
SUBSTANCE: invention is related to the field of facilities for automation of different liquids level detection in industrial and household reservoirs, and also for detection of liquids availability and flow in pipelines. Method is based on application of two thermistors that have identical thermal characteristics, and includes heating of one of the thermistors by electric current and its cool-down due to heat transfer to environment, periodic measurement of voltage drop at thermistors, calculation of informative parameter, its comparison with threshold value and making decision on availability or unavailability of liquid at controlled level. At that one of thermistors is periodically heated by short pulses from power supply source. After heating is completed, ratio of non-heated and heated thermistors' voltages are repeatedly measured, and as informative parameter scaled time derivative is calculated by means of specified ratio measurement results array processing. Device for method implementation contains two thermoresistors, which are installed in sensitive element, connected to power supply source and which have temperature resistance coefficients (TRC) of the same sign and identical coefficient of heat emission in gas. Besides, it also contains analog-digital transducer and comparator, reference inlet of which is connected to source of reference signal, and outlet is connected with actuating device. Moreover, device is equipped with pulse switch and serially connected regulator of heating time and synchroniser, and also calculator of scaled derivative. For alarm on liquid flow availability, device is additionally equipped with the second comparator that is connected parallel to the first one, and the second actuating device.
EFFECT: higher efficiency of liquid level detection by increase of device actuation fast-action, reduction of power inputs and expansion of its application field.
13 cl, 3 dwg
FIELD: measuring technology.
SUBSTANCE: invention refers to a measuring device for determination of an amount d(V(z)) of conducting liquid of the conductivity LF by a capacity with vertically (z-direction) varied filling points. There is provided conductivity metre which among others has at least two electrodes extended in a z-direction. The capacitance parametres and/or the metres are ensured so that it/they can be described by means of at least one parametric function, fpi (V(z)) depending on V(z). At least one said parametric functions shall have exponential dependence on V(z). There is also described measuring element, and also method for determination of total amount of flowing liquid d (V).
EFFECT: simplified design of the device and method of measuring conductivity of the conducting liquid.
42 cl, 14 dwg
SUBSTANCE: method if based on measuring capacitance of a double-electrode capacitive liquid level sensor, which in turn in any sequence measures capacitance of the double-electrode capacitive liquid level sensor and capacitance of the same sensor is measured after connecting a capacitive sensor of dielectric properties to it, after which the level h from the upper end of the double-electrode capacitive liquid level sensor is calculated using the formula:
, where h is the level of the liquid in the reservior; CA is capacitance of the double-electrode capacitive liquid level sensor; CB is overall capacitance of the double-electrode capacitive liquid level sensor connected in parallel to the capacitive sensor of dielectric properties; A, B and D are structural parametres of the double-electrode capacitive liquid level sensor and capacitive sensor of dielectric properties. The device for measuring liquid level has a double-electrode capacitive liquid level sensor made in form of a coaxial capacitor, and two cylindrical electrodes. The lower end of the inner electrode of the double-electrode capacitive liquid level sensor is connected to one of the electrodes of the capacitive sensor of dielectric properties through the closing contact of a reed relay, and the lower end of the outer electrode of the double-electrode liquid level sensor is connected to the second electrode of the capacitive sensor of dielectric properties.
EFFECT: high accuracy of measuring the level of different liquids, as well as elimination of measurement errors caused by change in dielectric permittivity of the measured liquid.
2 cl, 1 dwg
SUBSTANCE: sensor for monitoring the level of a liquid has a housing and a printed-circuit board on which there is a substrate having one or two identical film resistors (thermistors) and contact pads (conductors). The printed-circuit board is in form of a plate, one short side of which is rigidly attached to the base of the housing and on the edge of the opposite free side there is a hole whose diameter is 2…4 times larger than the width of the substrate lying over the hole and made from thin heat-insulating material. Each film resistor (thermistor) is in 'point' form with dimensions in the range (0.15…0.5) mm • (0.5…0.5) mm and thickness not more than 0.0005 mm. The boundary surface between each film resistor (thermistor) and contact pads of the substrate (conductors) is in form of broken lines consisting of straight sections.
EFFECT: high mechanical strength of the structure.