APPARATUS FOR MEASURING THE HARDNESS OF SOIL Russian patent published in 2021 - IPC G01N3/40 

FIELD: measuring.

SUBSTANCE: invention relates to tools for measuring the physical properties of soils, in particular, for determining the hardness of over-compacted soil with fixation of the data on paper tape. The apparatus is comprised of upper and lower support plates with stiffness units, guiding bars with a moving plate, a rail for paper with a spring clamp, an outer pipe with a central rod of a telescopic bar, a cylindrical spring, a carriage, a handle, a stopper unit containing a locking screw, and a recording mechanism with a rotary unit, fixed between the plates. A bushing is fixed on the central rod of the telescopic bar, wherein a spring spoke with a calibrated tip is installed on the thread inside the bushing, and a lower support seat for the cylindrical spring and a second moving plate with a nut are installed on the thread outside. A smooth cylindrical section is made in the inner lower part of the bushing before the thread, with a diameter equal to the diameter of the spring spoke.

EFFECT: facilitating the obtaining of reliable information on hardness during operation on over-compacted soil.

1 cl, 4 dwg