Abstract: A ballscrew assembly comprises: a nut having a nut body with a radially inner surface and a helical groove formed on the radially inner surface; a screw shaft disposed within the nut, the screw shaft comprising a radially outer surface and a groove formed on the outer surface, the groove on the screw shaft cooperating with the groove on the nut to define a helical raceway for a plurality of balls; at least one lubricant reservoir formed in the nut body at or adjacent to an end of the helical raceway; and a lubricant passage extending through the nut body and fluidly coupled to the at least one lubricant reservoir; wherein the lubricant reservoir is fluidly linked to the helical groove of the nut via the lubricant passage.

Abstract: An apparatus for reducing or eliminating gas lock in a downhole pump is provided. The apparatus has a ported bushing connecting to an upper standing valve at a first, uphole end and connecting to a lower standing valve at a second, downhole end. The apparatus also has one or more vents. In one embodiment, the apparatus is coupled downhole of a traveling valve of a downhole pump such that, on each upstroke, the one or more vents of the apparatus draw liquid from the annulus between the pump and the tubing into the passage between the upper and lower standing valves for opening the upper standing valve to accumulate liquid in the pump barrel below the traveling valve. The accumulation of liquid in the pump barrel below the traveling valve breaks gas lock and opens the traveling valve, ensuring the operation of pumping liquid from downhole to surface.

Abstract: A pump having an increased energy efficiency is provided. The pump has an internal power fluid column and a transfer piston which is reciprocatingly mounted about the power fluid column. The transfer piston defines a product fluid chamber, located above the transfer piston valve, and a transfer chamber, located below the transfer piston valve. The power fluid column has at least one passageway, which allows the fluid inside the power fluid column to be in communication with a power fluid chamber. The power fluid chamber, the transfer chamber, and the product chamber are situated coaxially about the power fluid column.

Abstract: A micropump provided with a cylindrical body (1) containing a measuring chamber (10) defined by a piston (2) and communicating firstly with a tank via an inlet orifice (10a) provided with an inlet valve, and secondly with the outside via an outlet orifice (10b) provided with an outlet valve, the micropump being characterized in that the piston (2) is connected to an external reciprocating actuator, and in that at least one of said valves is constituted by a valve member (3, 6, 7) suitable for being driven in translation by friction contact with said piston (2) successively in one direction and then in the other, and whose stroke inside the chamber (10) is shorter than the stroke of said piston.

Abstract: The invention is a component of a subsurface traveling barrel bottom anchor pump comprising a traveling valve assembly which includes: a cylindrical valve body having a lower section, the lower section having a central bore therethrough and external threads which interact with a threaded connection on a traveling barrel to removably attach the valve body to the traveling barrel; an upper section having a rod connection externally threaded for attachment to a pumping rod; a center section having a fishing neck portion and cage portion; a valve cage accommodated entirely within the internal portion of the cage portion; a valve ball positioned within the valve cage; a valve seat abutting the valve cage; and a ball and seat plug threaded into the lower section of the valve body for retaining the valve seat in the valve body.

Abstract: A linear double acting reciprocating fluid pump is disclosed with novel anchoring means to remotely secure the pump down hole in deep well applications. The multiple piston pump may be cable operated or directly driven. Using the related remote pump lock in deep well applications, the well casing can double as a discharge conduit. The pump comprises a single tubular barrel containing opposing reciprocating pistons, each piston carrying ample fluid ports with binary valves. Mechanical linkages within the pump barrel alternately reverse opposing pistons causing them to converge and diverge, thus providing a substantially steady fluid discharge and a relatively level demand on the prime mover.

Abstract: In a screw injection molding machine comprising a non-return device at the screwhead, said device comprising a pressure ring which is displaceable on the screwhead between front and rear abutments, is guided in the cylinder by its outer periphery and defines a flow gap with its inner periphery, a check valve for closing the flow gap against reverse flow is disposed near the front of the pressure ring whereby to facilitate rapid response of the non-return device without loss of material and obtain a substantially constant weight of injected material, particularly in the case of materials of low viscosity. The check valve may comprise a lightweight washer or valve ring.