Abstract: A shaft seal assembly for sealing along a rotor shaft is provided. The shaft seal assembly includes a seal housing, annular inner and outer seal members, an annular middle element, and an end plate. The seal housing has a seal member bore and a shaft bore. The annular inner and outer seal members are configured to be disposed in the seal member bore. The middle element is disposed between the inner seal member and the outer seal member within the seal member bore. The end plate is attached to the seal housing and covers a portion of the seal member bore. The middle element biases the inner seal member against the seal housing and biases the outer seal member against the end plate.

Abstract: A shaft seal assembly for sealing along a rotor shaft is provided. The shaft seal assembly includes a seal housing, annular inner and outer seal members, an annular middle element, and an end plate. The seal housing has a seal member bore and a shaft bore. The annular inner and outer seal members are configured to be disposed in the seal member bore. The middle element is disposed between the inner seal member and the outer seal member within the seal member bore. The end plate is attached to the seal housing and covers a portion of the seal member bore. The middle element biases the inner seal member against the seal housing and biases the outer seal member against the end plate.

Abstract: This invention provides a ram for use in a mixer with counter-rotating non-intermeshing rotors on which the central portion of the ram utilizes a apex, either a point or a line produced by a “V” or similar shape, that protrudes a given distance into the mixing chamber and on which the end portions of the ram are either horizontal such that they do not protrude into the mixing chamber at all or are otherwise shaped such that they protrude into the mixing chamber less than the apex of the central portion of the ram.

Abstract: Four wing rotors for used in an internal batch mixer. The rotor has two long wings, and these two long wings have different approach angles and helix angles. The rotor has two short wings and these short wings also preferably have different helix angles and approach angles. The rotors provide improved distributive and dispersive mixing allowing for greater productivity in processing materials and producing more homogeneously mixed materials at lower discharge temperatures.

Abstract: Convenient access for quick and thorough clean-out and maintenance of an openable mixing chamber and both rotors in two-rotor continuous mixers for plastic materials is advantageously achieved by making each rotor in three separate pieces: a drive journal, a rotor body (also called a "rotor section" or a "rotor") and a driven journal. These three separate pieces of each rotor are axially aligned, with the rotor body being positioned between the drive journal and the driven journal. Each rotor body is disengageably coupled to its respective drive and driven journals. The drive and driven journals are rotatably mounted in bearing assemblies which are separate from the mixing chamber barrel (also called a "mixing chamber housing").

Abstract: Multi-screw, extrusion-compounding machines having co-rotating screw assemblies incorporating sets of modular mixing elements of non-symmetrical geometries with relatively large wing tip clearances. These sets of non-symmetrical modular mixing elements are removably mountable at any suitable axial locations along their respective rotationally-driven screw shafts for optimizing performance in relationship to particular plastic material and particular additives being compounded. The non-symmetrical geometries provide dynamic wedging pressurization for repeatedly propelling relatively large circumferential flows of the plastic material through large shear clearances. Due to the relatively large shear clearances, the plastic material is mixed at less elevated and more uniform temperatures than usually occurs with use of prior symmetrical kneading blocks or kneading discs. At less elevated temperatures most plastic materials exhibit increased viscosities.

Abstract: A coupling mechanism for quickly coupling a rotor body to its drive and driven journals and obtaining radial and axial alignment thereof in a closely confined space is provided. The coupling mechanism includes a split ring collar and a clamping ring securely holding in appropriate placement a chamfered split ring for radially and axially aligning the rotor and the journals, referred to as co-axial alignment.

Abstract: A coupling mechanism for quickly coupling a rotor body to its drive and driven journals and thereby obtaining radial and axial alignment thereof in a closely confined space is provided. The coupling mechanism includes a split ring collar and a clamping ring securely holding in appropriate placement a chamfered split ring for radially and axially aligning the rotor and the journals, hereinafter referred to as co-axial alignment.

Abstract: Convenient access for quick and thorough clean-out and maintenance of an openable mixing chamber and both rotors in two-rotor continuous mixers for plastic materials is advantageously achieved by making each rotor in three separate pieces: a drive journal, a rotor body (also called a "rotor section" or a "rotor") and a driven journal. These three separate pieces of each rotor are axially aligned, with the rotor body being positioned between the drive journal and the driven journal. Each rotor body is disengageably coupled to its respective drive and driven journals. The drive and driven journals are rotatably mounted in bearing assemblies which are separate from the mixing chamber barrel (also called a "mixing chamber housing").

Abstract: Rotor zone cooling method for channeling liquid coolant flow in rotors in continuous mixers provides for predetermined zones along the lengths of the rotors to be cooled as may be desired and provides for other predetermined zones to remain neutral. A sequence of alternating cooling/neutral/cooling/neutral/cooling/neutral zones can be provided, including zones of various possible lengths, locations and numbers of such zones for tailoring or customizing these zones to optimize temperature conditions along a rotor depending upon mixing requirements and characteristics of plastic materials being mixed. A central coolant feed tube conveys coolant from an entrance into the bore to a discharge end of the feed tube positioned near the bore terminus in a first cooling zone. Coolant flow is diverted into isolation channels within isolation tubing sections spaced inwardly from the rotor bore wall for creating a neutral zone.

Abstract: Multi-screw, continuous mixing and kneading machine for plasticizable compounds with screws, which rotate in a housing and which penetrate the cylindrical housing section, enclosing the screw concerned, and exhibit feed and discharge zones and intermediate melting, mixing and kneading zones, where the feed and discharge zones are formed by intermeshing screws that rotate in the same direction, and kneading elements are disposed in the melting, mixing and kneading zones. The kneading elements comprise axially extended polygons, whose surfaces are approximately flat and whose edges travel by one another with small clearance relative to the envelopes of the respective other polygon so as not to intermesh while rotating, where the edges of the housing section enveloping them maintain a distance that is significantly greater than the clearance.

Abstract: A one-piece barrel for a hot-fed extruder extends from drive means at its upstream end to its discharge mouth near the downstream end of the feed screw. This one-piece extruder barrel has a split-level, in-feed opening adapted for connecting a strong, reinforcing converging hopper in close tolerance therewith for feeding molten plastic into the extruder barrel through this in-feed opening. A feed screw propels along the barrel molten plastic fed into the barrel through the in-feed opening. The barrel is a one-piece, integral, strong, cylindrical member with an axial bore whose entire length may be finish machined at one time. Such one-time finishing of the entire bore of a barrel is not possible in prior hot-fed extruder barrels, because they were built up from multiple sections assembled end-to-end to form the whole barrel.

Abstract: Continuous mixers of plastic materials are equipped with greased journal bearing assemblies instead of bulky, expensive, pumped circulating-oil lubricating systems, usually involving oil-cooling heat exchangers with circulating water. Such pumped oil systems having traditionally been employed in the past for lubricating journal bearings of the two rotors in such mixers. Novel thermal isolation of the journals for the two rotors separates their bearing assemblies from the severe heat being generated during mixing of plastic materials by continuous rotation of the two rotors within the mixer barrel. Localized cooling provides heat sinks for the drive and driven journals of each rotor. The rotors are shown as three-piece assemblies with drive and driven journals separate from the main rotor body.

Abstract: Quick-disconnect couplings for three-piece rotors in a two-rotor continuous mixer for plastic materials enable a main rotor section (or "main rotor body") of each rotor to be uncoupled from a drive journal located at one end of the main rotor section and a driven journal located at the other end of the main rotor section.

Abstract: Rotor zone cooling apparatus channels liquid coolant flow in rotors in continuous mixers of plastic materials for causing predetermined zones along the lengths of the rotors to be cooled as may be desired and for other predetermined zones to remain neutral, i.e. without significant cooling. A sequence of alternating cooling/neutral/cooling/neutral/cooling/neutral zones can be arranged, including zones of various possible length, various possible locations and various possible numbers of such zones. These zones are tailored or customized for optimizing temperature conditions along a rotor depending upon the mixing requirements and characteristics of plastic materials being mixed. Within an axial bore in a rotor is inserted a novel elongated cooling tubing assembly which rotates with the rotor. For creating a neutral zone, coolant flow is diverted inwardly into an isolation channel within an isolation tubing section spaced inwardly from the rotor bore wall.

Abstract: Flowable molten plastic material is fed downwardly into an adjustable converging hopper mounted on a horizontal extruder barrel. This hopper is positioned around an opening feeding down into the barrel for guiding and deflecting a descending "rope" of plastic material into engagement with screw flights of a rotating feed screw extending along the axis of the extruder barrel. The hopper comprises a box-like structure open at top and bottom and having two opposed side walls which slope inwardly downwardly toward each other for providing a downwardly converging configuration with a pair of vertical parallel end walls interconnecting the side walls. A larger of the two sloping side walls extends downwardly farther than the other and is inclined to vertical at a large angle than the shorter side wall.

Abstract: Two horizontally opposed winged rotors move in synchronism to define a cyclically varying window between them such that improved mixing results are achieved. The wings are provided in diagonally opposed pairs such that the leading ends of all wings move in pairs through the horizontal plane of the window.

Abstract: Four-wing, non-intermeshing rotors are optimized for synchronous rotation to be driven by synchronous drive means at a constant 180.degree. phase angle, there being two long wings and two short wings on each rotor. A first long wing and first short wing originate at a first end of each rotor, and a second long wing and second short wing originate at the second end of each rotor, the helix angle "A" being the same for all wings on both rotors, and being in the range from about 10.degree. to about 50.degree.. The axial length l.sub.1 is the same for all long wings, the axial length l.sub.2 also being the same for all short wings. Each rotor has a transition zone opening between the termination of a short wing and the termination of the next succeeding long wing relative to the direction of rotation, the next succeeding long wing originating at the opposite end of the rotor from the short wing.

Abstract: A batch mixer has position monitoring means for the ram operably coupled to the ram moving motor to move the ram within a range of positions adjacent the ram's "down" position to improve mixing by allowing limited upward movement of the ram as a result of internal pressures inside the mixer. Excessive ram return movement is prevented however, and the limited ram movement is achieved by feedback control influence on the pressure to the fluid actuator that operates the ram. Also disclosed is a feed-back control for batch size to assure that optimum use is achieved for the mixer during each batch mixing interval.

Abstract: Non-intermeshing four-wing and three-wing rotors for use in high intensity mixing machines of the batch type provide new sequences and new characteristics of dynamic interactions for achieving advantageously increased mixing effectiveness and strength of the rotors. These new rotors are adapted for driving at unequal speed (unsynchronized rotation) or at equal speed (synchronized rotation). In the four-wing rotors, long wings and short wings both originate from both ends of the rotor. The new four-wing and three-wing rotors intensify axial mixing action and transverse distributive mixing for causing the mixes (batches) to become more homogeneous. The markedly increased twist angles T in both types of rotors decreases the volume of material "sitting" at the center of the mixer for maximizing the dispersive mixing or high shear occurring between wing tips and wall surface of each rotor cavity.