Abstract: A positive displacement rotary mechanism has four identical rotary helical intermeshing lobes that cooperate with a stationary cylindrical member extending centrally thereof to define repetitive working space internal of the lobes having boundaries along and between the lobes and along and between the lobes and the cylindrical member which boundaries move on rotation of the lobes to effect expansion and contraction of the working space while repetitively moving same from one of the ends of the lobes toward their other end.

Abstract: A positive displacement rotary mechanism has three and alternatively four identical rotary helical intermeshing lobes of continuously varying pitch that cooperate with a stationary cylindrical member extending centrally thereof to define a repetitive working space internal of the lobes having boundaries along and between the lobes and along and between the lobes and the cylindrical member which boundaries move on rotation of the lobes to effect expansion and contraction of the working space while repetitively moving same from one of the ends of the lobes toward their other end.

Abstract: A positive displacement rotary mechanism has three identical rotary helical intermeshing lobes that cooperate with a stationary cylindrical member extending centrally thereof to define a repetitive working space internal of the lobes having boundaries along and between the lobes and along and between the lobes and the cylindrical member which boundaries move on rotation of the lobes to effect expansion and contraction of the working space while repetitively moving same from one of the ends of the lobes toward their other end.

Abstract: A positive displacement rotary mechanism has three and alternatively four identical rotary helical intermeshing lobes that cooperate with a stationary cylindrical member extending centrally thereof to define a repetitive working space internal of the lobes having boundaries along and between the lobes and along and between the lobes and the cylindrical member which boundaries move on rotation of the lobes to effect expansion and contraction of the working space while repetitively moving same from one of the ends of the lobes toward their other end.

Abstract: A rotodynamic fluid machine comprising a plurality of separate coaxial cylindrical chambers in each of which a drive rotor is positioned. The drive rotors mesh with corresponding sealing rotors and have blades that are curved in such a manner so that if the rotors are placed in abutting relationship that the blades on one rotor will mate with the contiguous blades of the other rotor and extend around the circumference of the rotor so as to overlap in a circumferential direction.

Abstract: A screw pump including a screw assembly in a sleeve, the assembly comprising a drive screw having protruding threaded sides, and multiple driven screws having concave threaded sides which are closely meshed with the drive screw, thus forming a series of sealed chamber. The screw pump further includes one or more channels which are formed in the circumferential direction around the periphery of the driven screws, so that the final sealed chamber adjacent a discharge port of the pump partially communicates with the port through the channels shortly before the chamber completely opens to the port.

Abstract: A device preferably utilized for pumping oil or other fluid from a drill hole in the ground, said device including a pump lowered into the hole and coupled to a drive motor situated under it. The pump comprises a hydraulic screw pump including a housing in which there is mounted a screw array in the form of a drive screw provided with a shaft coupled to the drive motor, and at least one running screw meshing with the drive screw. The rotational direction of the drive motor is such that the screw array pumps the liquid from an inlet, made radially in the housing and in communication with the liquid in the drill hole, to an outlet arranged at the end of the screw array remote from said shaft.

Abstract: A screw pump of the kind including a screw array consisting of a central screw (1) with convex flanks and one or more side screws (2) with concave flanks, the threads being formed such that coacting screws seal against each other with the screw array being sealingly surrounded by a screw housing (3), so that at least one closed chamber is formed by the sides and roots of the threads as well as the screw housing, the chamber migrating axially from the inlet end of the screw array to its outlet end when the screws are turned, and is in communication at least during a portion of its migration with a pressure fluid source (9) via at least one duct (14) made in the pump. To prevent the occurrence of, and to eliminate, existing air and gas bubbles in the liquid chamber without efficiency being unnecessarily deteriorated, the pump is provided with a regulating device (15) coacting with the duct for adjusting the quantity of liquid flowing to the chamber from the pressure fluid source.

Abstract: A motor-pump unit consists of a screw shaft pump and a slot-barrel motor located on the pressure side of the pump. The motor-pump unit is provided with a rigid, preferably one-piece, shaft by which the motor drives the pump. The motor is located on the pressure chamber of the pump with a bearing between the motor and pump. The shaft is supported within the pump, in part by the bearing, and the rotor of the motor is cantilevered on the free end of the shaft outside the pressure chamber. The pot-shaped stator part of the motor is telescoped over the rotor and fastened directly to the pressure side of the pump.

Abstract: The invention relates to hydraulic screw machines of the type having a screw array in a sealingly surrounding housing. The object of the invention is to reduce the length of the machine with unchanged number of seals in the screw array. This is achieved by providing at least one of the inlet and outlet openings to the screw array as a bore extending radially through the housing and in such a position that in at least some angular position of the screw array, it seals against the housing wall in the region which is within the axial extension of the opening.

Abstract: A hydraulic screw machine comprises a driving screw and at least one impeller screw with a balance plunger at its end. The thread of the impeller screw is complete with full depth all the way to the balance plunger. The length of the plunger is less than the width in the axial direction of the thread groove in the driving screw. The balance plunger is mounted on an axial pin on the end of the impeller screw.

Abstract: A screw pump having a unit which includes a drive screw and at least one impeller screw that meshes therewith, arranged within a casing that sealingly encloses the screws, each impeller screw on the pressure side being provided with a pin mounted in a sleeve, the interior of which communicates with the suction side through channels in a pump housing and the drive screw. There is a disc-like packing between an end surface of each sleeve and an end wall that closes the pressure side of the housing, through which end wall the channels partially extend, and through which a drive shaft is extended for the drive screw. The invention provides that each sleeve has one or more deformation zones on a side thereof remote from the packing, and facing a fixed surface in the housing, which zones are arranged to abut the fixed surface in the housing.

Abstract: A screw pump includes a screw unit having a drive screw and two impeller screws arranged symmetrically around the drive screw. The screws are enclosed in a housing having mutually intersecting passages for accommodating the screws, and the unit is constructed so that the screws seal against each other and against the housing to form chambers in which liquid is carried from the suction side to the pressure side during rotation of the screws. On the pressure side in the passage accommodating one of the impeller screws there is formed a recess which extends from the pressure side and the length of which is such that each chamber is opened at separate time intervals with respect to the two impeller screws instead of simultaneously.

Abstract: A positive displacement, progressing cavity device with interengaging axially twisted rotors that define sealed cavities or chambers which develop at the inlet of the device and progress axially to the outlet of the device in response to synchronized rotor rotation.As the cavities or chambers progress axially they may be constant in volume, increasing in volume, decreasing in volume or any combination of constant, increasing and decreasing volume depending on the change in pitch of the axial twist of the rotors. All rotors of any one device are identical in geometric configuration and are arranged in groups of four, such that each rotor is in constant engagement with its adjacent rotors.