Provided is a gear pump device that enables improvement in volumetric efficiency and manufacturability, and also makes it possible to ensure sealing property and to reduce drive torque. According to the present invention, a sealing mechanism is provided with an annular rubber member, an outer member, and an inner member, wherein: the inner member has, at an end of an outer peripheral wall on the side of an inner gear in the axial direction, a notch which is recessed radially inward of the inner gear so as to form, together with an axial one end face of the inner gear, a depressed part; and the outer member has an insertion part which is disposed within the depressed part and which abuts against the axial one end face of the inner gear so as to constitute a part of a sealing surface on the other side.

An oil pump that sucks and discharges oil, includes: a housing portion; a stator portion including an outer ring that is accommodated inside the housing portion, and a main pressing end that is formed to protrude outward from an outer circumferential surface of the outer ring; a rotor portion accommodated inside the outer ring, and sucking and discharging oil through rotation; a spring portion including a main spring that presses the stator portion; a guiding portion including a first guiding member that is installed on the outer circumferential surface of the outer ring; and a sealing portion interposed between the housing portion and a stator portion to prevent the oil flowing into the variable chamber from leaking into another space between the housing portion and the stator portion.

A high speed, rotary lobe gear pump assembly is provided which combines a positive displacement lobe gear pump having wipers with a centrifugal pump utilizing an impeller. The centrifugal pump feeds high pressure fluid flow directly into the lobe gear pump allowing the gear pump to rotate at high speeds without cavitation. The high speed capability of the pump assembly allows the lobe gear pump to operate without speed reduction gearing for the motor shaft.

The present invention relates to a fixed displacement pump for use for conveying a hydraulic fluid in a closed hydraulic circuit, a closed hydraulic circuit, a construction machine and a method for operating a fixed displacement pump in a closed hydraulic circuit.

Disclosed is a gear pump (10) comprising a contra rotating gear element pair (30 and 40) mounted within a housing (20), each gear element having complementary gear teeth sets providing a pumping action in use, said teeth being formed from an annulus (34 and 44) of generally rigid construction mounted on a relatively flexible inner section (35 and 45), the gear pair being mounted such that their respective annuli are biased into resilient contact with the housing to provide a sliding seal.

Overheating of a process liquid retained in a reservoir of a multiphase pump during extended gas slugs is avoided by circulating a cooling liquid in thermal contact with a process liquid through an external cooling apparatus, which can include a heat exchanger. In some embodiments, process liquid from the reservoir is circulated through the cooling loop, while in other embodiments a separate cooling liquid is circulated between a reservoir heat exchanger and the external cooling apparatus. The liquid in the cooling loop can be circulated by a separate cooling pump, or process liquid can be circulated through the cooling loop due to a pressure differential between an inlet and an outlet of the cooling loop within the multiphase pump. The multiphase pump can be a twin screw pump, and the reservoir can be formed between outer and inner casings of the multiphase pump.

A pump fluid driving apparatus includes a housing having a chamber, with two gears mounted within the chamber. The housing includes a first rounded wall section and a second rounded wall section, the first and second rounded wall sections defining at least a portion of the chamber. The gears have teeth located about their respective peripheries and operatively positioned with the teeth of the first gear and the teeth of the second gear intermeshed. The teeth include slotted teeth and solid teeth arranged with uniform spacing in a repeating pattern about the periphery of each of the gears, with each of the slotted teeth having a vane slot and a radially extending vane extending from the vane slot, and each radially extending vane being movable within the respective vane slot and being configured to contact the respective first or second rounded wall sections.

In a gear pump device for rubber extrusion, prolongation of the maintenance intervals is intended by preventing rubber scorch occurring at the gear support-shaft portion. It has a bushing ring 5 inserted in a gear-housing bore 3 of a housing 4. The bushing ring 5 rotatably supports a support-shaft portion 7 of a gear 2 accommodated in the gear-housing bore 3. The bushing ring 5 has a bearing 15 and a sealing means 16 built-in. The sealing means 16 includes a seal ring 22 of which cross section is ]-shaped and which has a first lip portion 22i contacting with the outer peripheral surface of the support-shaft portion 7, a second lip portion 22o disposed outside thereof in the radial direction, and a side wall portion 22m connecting between outer ends in the axial direction, of the first and second lip portions 22i, 22o.

A containment assembly for a pump provided with at least one pumping group and with 5 at least one power transmission system to such a pumping group. The containment assembly includes a substantially cylindrical containment vessel provided with an opening at one of the ends thereof, configured to at least 10 partially enclose the pumping group and the respective power transmission system. The containment assembly also includes at least one closure plate, sealably coupled with the containment vessel at the open end thereof and configured to hermetically enclose, in 15 cooperation with such a containment vessel, the pumping group and the respective power transmission system. On a predetermined contact portion between the containment vessel and the closure plate at least one wave spring is provided, configured to keep the pumping group 20 dynamically under compression by means of the closure plate.

The invention relates to an eccentric screw pump, comprising at least one stator (1) composed of an elastic material and a rotor (2) that can be rotated in the stator (1), the stator (1) being surrounded by a stator casing (3) at least in some regions. The stator casing (3) consists of at least two casing segments (19) as a longitudinally divided casing and forms a stator clamping device, by means of which the stator (2) can be clamped against the rotor (1) in the radial direction. The pump is characterized in that the casing segments (19) have at least one clamping flange (20) having first clamping surfaces (21) at each end of the casing segments and that one or more clamping elements (22, 23), which can be displaced in the axial direction and have second clamping surfaces (24), are placed onto the clamping flange (20), the first clamping surfaces (21) and the second clamping surfaces (24) being designed in such a way and interacting in such a way that the stator casing (3) can be clamped against the stator in the radial direction in the course of an axial displacement of the clamping elements (22, 23).