A pump diaphragm for a diaphragm pump for conveying a fluid includes a solid core with a connection device for a drive rod of the diaphragm pump, and a plate-shaped elastic diaphragm body made of rubber having a peripheral clamping edge. The solid core is embedded at least partially in the diaphragm body and the solid core is produced from a thermoplastic and forms covalent bonds with the elastic diaphragm body made of rubber without adhesive. For this purpose, the thermoplastic, for example polyamide 612 or polyphenylene ether, and the rubber, a periodically cross-linked rubber such as EPDM, are selected in such a way that they are covalently cross-linked with one another at the boundary layer. In this way, a bonding layer that is susceptible to weakening or destruction is not present between the core and the diaphragm body.

An enhanced elastomeric stator assembly and method of making the same is disclosed. The elastomeric stator may be structurally, thermally, and/or chemically enhanced through the incorporation of graphene particles, cross-linkable polymers, coupling agents that extend cross-links, and by the reduction of filler material. The graphene particles can be incorporated in functionalized or non-functionalized form or in a combination thereof, the functionalized graphene increasing the number of cross-links in the overall structure, thereby enhancing the structural robustness of the elastomeric stator. The compound can be formulated to have a relatively low viscosity and other characteristics that allow the material to flow through a mould cavity.

A stator for use in a positive displacement motor or a progressing cavity pump. The stator comprises an elastomer mix preferably including rubber and a fiber reinforcement. The fiber reinforcement includes a plurality of fibers. The elastomer mix is formed into a stator via an injection molding process. The injection molding process includes a shear flow step in which shear flow is induced in the elastomer mix while the elastomer mix is in an uncured state. The shear flow modifies the orientation of the fibers into an advantageous modified fiber orientation. Shear flow is induced preferably via differential rotation of injection mold assembly elements during the injection molding process. Methods of manufacturing the stator are also disclosed.

A motor operated compressor includes an orbiting scroll that defines a compression chamber together with a fixed scroll. The compressor includes a main frame disposed around and supporting the orbiting scroll. The main frame defines a back-pressure chamber together with the orbiting scroll. The compressor includes a groove disposed in one of the orbiting scroll and the main frame. A first sealing member is inserted into the groove. A second sealing member is inserted into the groove to elastically press the first sealing member into close contact with the orbiting scroll or the main frame. A radial distance (a) between an outer wall of the groove and the first sealing member is 6 to 8% (0.06a/W0.08) of a difference (W) between an outer radius (OR) and an inner radius (IR) of the first sealing member (W=ORIR).

The dynamic fatigue and hysteresis performances of fiber reinforced rubber compounds are compared using different plasticizers. Fiber reinforced rubber compounds including a non-linear functionalized fatty acid ester, preferably a trimellitate, and more preferably Tris (2-Ethylhexyl) Trimellitate (TOTM) are shown to demonstrate greatly improved dynamic fatigue and hysteretic performance as compared to reference fiber reinforced rubber compounds including conventional reference plasticizers such as Di-isodecyl phthalate (DIDP).

One example of a gerotor pump includes an inner rotor comprising multiple teeth, the inner rotor configured to rotate about a first longitudinal gerotor pump axis. The gerotor pump also includes a hollow outer rotor including an outer surface and an inner surface having substantially identical contours, the inner surface configured to engage with the multiple teeth and to rotate about a second longitudinal gerotor pump axis. The pump includes a pump housing within which the inner rotor and the outer rotor are disposed, wherein the outer surface of the outer rotor defines gaps between the pump housing and the outer rotor.

A hybrid elastomer/metal on metal motor for a helical gear device includes a rotor and stator comprising a hydraulic motor that produces work when a working fluid is pumped therethrough. The improvement involves the stator being, for part of its length, a conventional or even wall stator, using an elastomer to form a seal against the moving rotor. The stator's remaining length comprises a profiled rigid surface that forms a seal directly with the moving rotor. This gives the motor the high efficiency of the elastomer sealing against the rotor, and simultaneously provides a backup of the stator's rigid section allowing continued motor operation at reduced efficiency, if the elastomer part failed in service. The invention also includes combinations of a regular disk stack with a rubber lining, a rigid material disk stack (or unitized element) and a circular rigid sleeve which react to rotor sideloading while permitting proper rotor orbiting.

One example of a gerotor pump includes an inner rotor comprising multiple teeth, the inner rotor configured to rotate about a first longitudinal gerotor pump axis. The gerotor pump also includes a hollow outer rotor including an outer surface and an inner surface having substantially identical contours, the inner surface configured to engage with the multiple teeth and to rotate about a second longitudinal gerotor pump axis. The pump includes a pump housing within which the inner rotor and the outer rotor are disposed, wherein the outer surface of the outer rotor defines gaps between the pump housing and the outer rotor.

A volume control actuator including a non-contact cylinder. An installation frame has a predetermined height and size. First and second installation spaces are defined in upper and lower portions of the installation frame, respectively. A pressing unit is vertically disposed on top of the installation frame to move a reciprocating rod in the first installation space reciprocating stroke movements. A fluid pipe is provided in the second installation space and connected to an installation plate to obtain a path through which fluid flows. Both ends of a rubber cylinder are fixed to a top surface of the installation plate and one end of the reciprocating rod. The rubber cylinder is provided in the first installation space so that the volume of the rubber cylinder changes in an expanding and contracting manner in response to the stroking of the reciprocating rod, thereby causing fluid in the fluid pipe to flow.

A rubber compound for use in a stator. The stator may be deployed in a positive displacement motor. The rubber compound includes a fiber reinforcement, wherein fibers in the fiber reinforcement create a grain direction in which with the grain is generally orthogonal to across the grain. In some embodiments, the rubber compound has a first value for 25% tensile Modulus across the grain and a second value for 25% tensile Modulus with the grain, wherein the first value is at least 10% lower than the second value. In such embodiments, the fiber reinforcement may further include a fiber loading of greater than 1.0 phr of fibers. In such embodiments, the rubber compound may further have a 25% tensile Modulus of greater than 400 psi across the grain and a 50% tensile Modulus of greater than 700 psi across the grain.