SU964544A2 - Anemometer - Google Patents

Description

(54) ANEMOMETER

The invention relates to a measurement technique and can be used to measure the velocities of air-gas environments in mine and industrial ventilation and in meteorology.

According to the main author. St. No. 732747 is well known for an anemometer, which contains a sensitive element in the form of a blade turntable, connected through an axis to a counter mechanism. The blades of the sensing element are fixed on the axes in a framework rigidly connected to the axis of rotation of the anemometer's rotor. The axes of the blades are offset from the middle of the area of their surfaces, and the frames limit the rotation of the blades around their axes at an angle of 90-180. This design of the anemometer sensing element implies that the blades have a variable frontal surface area (variable mid-section) due to partial rotation with respect to the direction of the measured flow.

A disadvantage of the known anemometer is that, due to the displacement of the axes of the blades, it is necessary to completely set the blades in order to properly install the blades.

when they interact with the flow) centrifugal forces arising during rotation of the spinner, which differ in size, act on the opposite parts of the blades. This prevents the blades from being positioned strictly along the flow of the test medium, as well as creating additional lateral dynamic pressures on the supports of the axis of rotation.

10 turntables and axes of the blades, which causes a decrease in the sensitivity of the device and the reliability of its readings.

The purpose of the invention is to increase the sensitivity and reliability of the anemometer.

The goal is achieved by the fact that the weights of the parts of the asymmetric blade are chosen from the ratio

one

20

 2

Claims (2)

—the weights of the parts of the blades-spacings from the centers of the tons of the respective parts of the blades to its axis of rotation in the frame. The drawing shows the anemometer spinner at a certain moment of the device operation at the speed of the measured flow DO, general view. The anemometer spinner has blades A, B, C and D fixed on axis 1 in frame 2, which are connected to the rotation of the wheel 4 by means of rigid rods 3. 2. (S S2) the incident current puts the blades A, B and G along the current, B - across. Due to the difference in aerodynamic resistance of the blades A and into the vertex, the blades are alternately placed in positions A, B, C and G. For the blades of the proposed turntable, the equality Jl P 2 of the anti-sweat weight is observed. relative to the axis of rotation within parts of the blade; -Y- and y- respectively, remove the centers of the weight of these parts from the axis of rotation p frame. The moments of the centrifugal forces acting on the blades, located along rigid bonds, are zero because their shoulders are zero. Thus, when setting the parameters of the blades according to no centrifugal forces on the location of the blades in relation to the measured flow and additional lateral dynamic pressure on the support of the rotation of the vane and the axes of the blades in the framework, the sensitivity and reliability of the anemometer increases. Taking into account the aerodynamic requirements for the flow around the blade profiles and the need to shift the axes of rotation of the blades relative to the mid-surface area of their surfaces, the ratio is. in practice, for example, as a result of creating parts of the blades t and ti from materials with different densities or their various thicknesses, and so on. For example, the part of the blade with a longer length is made of organic glass (density Ross 1.2 g / cm), and the part of the blade with a smaller length Ku, -from brass (JJ, 8.5 g /cm). Then, under a c and condition Ei), we have t IL / lK ei-i. or, 66S, - / OS .. which, when rotating the turntable, rotates each blade in positions from D to A and further to B along the measured flow (since 5: # S, namely S 84), where a, b , 5 and a, b, S - thickness, width and surface area (mid-section) of the corresponding parts of the blade. The fabrication of parts of the blades of the rotor from materials with different densities is one of the options for respecting the ratio. With the achievement of the following positive effect: an increase in the sensitivity and reliability of the anemometer readings due to the absence in this case of the effect of centrifugal forces on the location of the blades with respect to the measured flow and additional lateral pressure on the bearings of rotation of the turntable and axes. that blades within. The invention of the anemometer on the author. St. No. 732747, which means that, in order to increase the sensitivity of reliability, the weight of parts of the asymmetric blade is selected from the correlation of Pe and Pg - the weight of parts of the blade / in the distance of the blades of the corresponding parts of the blades to its axis of rotation in the frame. Sources of information that are considered in the examination 1. USSR author's certificate 732747, cl. G 01 P 5 / 06,16.02.78.