WELL EXPANDER Russian patent published in 2023 - IPC E21B7/28 

FIELD: construction.

SUBSTANCE: expansion is made in form of an inverted cone, at the base of which a horizontal surface is formed, located directly under the sole of the existing foundation. A well expander with a device in the upper part of the expansion of the horizontal surface, including a shaft with a rigidly attached upper coupling, having an upper axle, on which a spatial pantograph mechanism is pivotally attached, consisting of a pivotally connected upper and lower wings, equipped with rock cutting knives, while the upper axis has a pivotally attached upper link, in the lower part of which a middle axis is arranged, a lower link is pivotally attached to the middle axis, having a lower axis located in the guide post, which is rigidly connected in the lower part to the lower coupling rigidly attached to the shaft, while the lower coupling, by means of the bearing assembly, is pivotally connected to the soil collector, and the upper and lower couplings are equipped with upper and lower shells, on the inside of which a vertical latch is rigidly attached, which is rigidly fixed by a horizontal latch to the corresponding coupling, and a flexible rod is attached to the lower axis of the wings, passing through a through hole located in the upper sleeve attached to the adjustable rod tensioner located on the shaft.

EFFECT: increase of the bearing capacity of existing foundations of buildings and structures by driving bored piles with expansion.

1 cl, 3 dwg