SU798489A1 - Double-limit level indicator - Google Patents

Description

(54) TWO-DEPENDENT LEVEL SIGNALIZER

This invention relates to instrumentation engineering and can be used to signal limit levels on river and sea vessels, oil station tankers, mines, locks, in the chemical industry.

A two-level level indicator device is known, which contains a permanent magnet connected by a flexible coupling with a float moving relative to a stationary magnet, and a magnetically controlled contact l.

The disadvantage of this signaling device is a low scope, since it is possible to control only two levels, the difference between which in height is not greater than the height of the float.

Closest to the proposed is a two-limit signaling device containing connected between. two floats associated with a displacement transducer mounted in housing 2.

A disadvantage of the known alarm device is low reliability of operation caused by fluctuations in the level of the liquid, for example, when the ship is rolling

The purpose of the invention is to increase the reliability of the dual limit level indicator.

This goal is achieved by the fact that the displacement transducer is made in the form of a movable magnet of a soft disk with a ferromagnetic screen mounted on it by means of a non-magnetic cylinder, inside which

0 there is a magnetically sensitive element interacting with a permanent magnet rigidly fixed in the recess by a magnet of a soft washer fixed in the housing.

five

The drawing schematically shows the proposed device, a General view.

The two-limit level switch contains a float system,

0 made in the form of a float 1 and a float 2, connected by a mecha of a thong 3 or a flexible connection. The body 4 has a displacement transducer, made in the form of

Claims (2)

5 of a magnet movable magnet 5, the core of which is attached to the float system; On the magnet disk 5 is fixed by means of a nonmagnetic cylinder 6 a ferromagnetic screen 7, inside which is placed a magnetically sensitive element 8, which is fixed by means of a cup 9 to a rack 10. a washer 11, in the recess of which an annular permanent magnet 12 is rigidly fixed. The cover 13 seals the sensor. The two-limit level indicator works as follows. When the liquid is at the lower level, the magnetically soft disk 5 is in the lower position. The magnetically sensitive element 8 is shielded from the floor of the ring permanent magnet by a ferromagnetic screen 7 and the device generates a signal of the lower liquid level. When the liquid level reaches the upper float 2, the rod 3 rises to the ring magnet 12 and lifts the ferromagnetic screen 7, outputting it to the plane of the ring magnet 12. The field of the ring magnet 12 acts on the magnetosensitive element 8, and issues a high level signal. the upper float 2 to the lower 1 magnet gk disk 5 is in the upper position held by the attractive force of the ring magnet 12, since the fan is shta. 3 and the floats 1 and 2 are weakened by the pulling force of the float 1. Only when the level of the bottom float 1 is reached, the magnet disk 5 drops down, as the weight of floats 1 and 2 becomes greater than the holding force of the ring magnet 12. This method provides a relay mode of operation of the sensor and excludes frequent triggers when the liquid level fluctuates, for example, when the ship is rolling. For separation, the following inequality should be fulfilled. Inequality On the other hand, when the level raises the upper float 2 and the magnet disk 5 is attracted to the ring magnet 12, the level fluctuations around the float 2 will not remove the soft disk 5 from the ring magnet 12 with the magnet, even if the float 2 comes out of the water, t to When the F power of the float 1 together with the tearing force F is greater than the weight of the tangi and the floats, i.e. float. After lifting the boom, it is necessary that the total buoyancy force of the floats F + Fj be greater than the weight of P Fg + F (Vg + V). The sensor can be used with large differences in fluid levels. In this case, the floats are connected by a flexible link, and the lower float is fixed in its vertical movement to exclude its floating on the surface of the liquid. The proposed two-limit level switch is simple in design and reliable in operation, as it provides a low, but a clear signal activation, eliminates frequent alarms that adversely affect the automation components and actuators, for example, when the ship is rolling. Claims of the invention A two-limit level switch, comprising interconnected two floats, connected to a displacement transducer installed in a housing, characterized in that, in order to increase the reliability of operation, the displacement transducer is made in the form of a flexible magnetic disk mounted on it with a non-magnetic a cylinder with a ferromagnetic shield, inside which is placed a magnetically sensitive element, the interaction of cadmium with a permanent magnet rigidly fixed in the recess of a soft magnet fixedly mounted in the housing. Sources of information taken into account in the examination 1. USSR author's certificate number 494609, cl. G 01 F 23/12, 1972. 2. Authors certificate of the USSR 371450, cl. G 01 F 23/06, 1971 (prototype). W / j //// 77 / Yjy77 //// Y / ////// / 77 / y / y / 77/77 j, YU 13 /