| 摘要 |
FIELD: mining industry. ^ SUBSTANCE: device has surface composed of upper section with wedges and lower section and backfill material placed on said surface. Upper section is made in form of a rectangle, composed of rectangular triangle and rectangular trapezoid with possible displacement of trapezoid along triangle hypotenuse. Lower section is made of two plates, mounted on holder, fixed to pipe for feeding compressed air. Plate, positioned above the trapezoid, is mounted with possible counter-clockwise rotation around holder. Value of greater base of trapezoid hdelta is selected from relation hdelta = m - 0.9k, where m - bed massiveness, m, k - size of backfill material, m. ^ EFFECT: simplified construction, lower laboriousness. ^ 2 dwg |
