HYDRAULIC DOWNHOLE MOTOR Russian patent published in 2019 - IPC E21B4/02 F04C2/107 F03C2/08 F04C13/00 F01C1/08 

FIELD: machine building.

SUBSTANCE: invention relates to hydraulic drives for rotary drilling located in a well. Hydraulic downhole motor comprises a stator, which is a tubular body with an elastomer-coated in it coating of an elastomer, adjacent to the inner surface of the tubular body, the elastomer liner is made with internal helical teeth, at each edge of the tubular body there is an internal thread and a rotor inside the stator with external helical teeth, the number of rotor helical teeth per unit is less than the number of helical teeth of the lining, the paths of the helical teeth of the lining and the rotor are proportional to their number of teeth, and central longitudinal axes of rotor and cover are offset to each other by value of eccentricity. Cross sections of external helical teeth at the edges of the rotor are outlined by an equidistant profile which decreases in the direction of the near end of the rotor, which is configured to shift each point of the profile in a radial direction along a vector connecting each point of the profile to the central longitudinal axis of the rotor, length L of each section of external helical teeth on the edges of the rotor, which is outlined by the equidistant profile in the direction of the near end of the rotor, and the radius R of the outer surface of the rotor on the length between the said sections are related by the relationship: L=(3.55÷5.55)R, wherein radius R_t each point of profile of outer surface of rotor on length of each section L on edges of rotor, on which outer helical teeth cross sections are outlined with equidistant profile decreasing in direction of rotor near end face, made with possibility to shift each profile point in radial direction along vector connecting each profile point to central longitudinal axis of rotor, and radius R_c each point of the profile of the external surface of the rotor on the length between the said sections, corresponding to each point of the profile on the length of each section L on the edges of the rotor along the vector connecting each point of the profile to the central longitudinal axis of the rotor, are related by the relationship: R_t=(0.85÷0.98)R_c.

EFFECT: increasing service life and reliability of the engine by reducing stresses along edges of the elastomer plate in the stator housing, thereby preventing cracking, peeling and breakage along the edges of the coating, where increased amount of heat is generated and stored from action of rotor twisting moments at its planetary-rotary rotation inside the lining, preventing drilling node clogging of drilling bit, required interval of well can be drilled to the end, economic advantages are provided for directed drilling of wells.

1 cl, 9 dwg