SU485358A1 - Densitometer for liquid media - Google Patents

Description

I

The invention relates to instrument engineering and can be used to measure the density of a fluid, for example for

; aviation density measurements .; fuels.

Known float densitometer containing two floats, on which compensatory weights are fixed, the centers are the same:

which are shifted relative to the points I of the application of pushing force, two mag-

: filament, mounted on floats, and a device for measuring the angle between floats; time-pulse method (electromechanical time-pulse modulator), consisting of two cores of magnetically soft material, which are driven

 rotation by an electric motor, and two induk-

 coils. The internal cavity of the sensor is filled with liquid, the density of which must be measured, while i float, pops up, rotates around i of its axis. At an angle at which M MOJJT from the effect of buoyancy becomes equal to the moment of the weight of the compensation weights. The angle between the floats is proportional. The density of the liquid to be measured. J

During its rotation, the core passes i near the permanent magnets mounted on the floats, their magnetic fields are ceressexat, as a result of which time-shifted pulses of electric current appear in the corresponding rollers. In the secondary transducer, the density is determined by the formula;

P k-a

where P is the density of the liquid;

Of - the angle between the floats; e1 is the time shift between the current pulses in the inductors;

T is the period of rotation of the korea;

| () (- constant.

The purpose of the invention is to increase the measurement accuracy.

For this, in the proposed device, permanent magnets on the floats are reinforced with opposite poles relative to the axis of rotation of the floats.

The drawing shows the design of the proposed densitometer for liquid media.

Inside the body 1, made in the form of a cylindrical cup, are placed on axis 2 two identical floats 3 and 4 „having the form of cylindrical sectors. The floats are reinforced with compensation weights 5 and 6, the centers of which are displaced & about the points of application of buoyancy. The floats are protected from the incident flow by the casing 7 with a small opening for the flow of liquid. On the floats are also strengthened magic-, you are 8 and 9, oriented relative to the axis of rotation of the floats with opposite names. In the hermetic cavity 10 there is a small-sized electric motor, 11, on the axis of which the measles 12 are reinforced with a magnet of a soft material and an induction coil 13.

The sensor is completely filled with a fluid whose density is to be measured. The floats 3 and 4, when they pop out, turn from around axis 2 to an angle at which the moment from the action of the buoyancy force becomes equal to the moment from the weight of the compensation weights 5 and 6, and the angle between the floats is proportional to the density of the liquid. The motor 11 drives the rotation of the bark 12, which is the magnetic core (core) of the induction coil 13. With its rotation, the measles passes alternately near permanent magnets 8 c 9 with a small

gap and crosses their magnetic fields, | as a result, electric current pulses occur in the coil 13. Since the magnets are oriented relative to the axis of rotation by the float and the core of the same poles, in the induction coil different polarity pulses appear, shifted in time by a time interval A b Because the pulses are different polarities, after

the selection in the phase selector of the secondary transducer establishes a single-line correspondence between the pulse and its corresponding magnet, i.e. float. Thus, there is no need for a second induction coil j and the core.

Subject invention

Densitometer for liquid media, comprising a case, inside which are placed two floats, reinforced with bearings on the axis of rotation, compensation weights installed offset from the points of application of buoyancy, permanent magnets mounted on the floats and a float movement detection unit that differs so that, in order to improve the measurement accuracy, the permanent magnets on the floats are reinforced with opposite poles relative to the axis of the float vrasheniya.