Baker Perkins Inc.

David B Todd

James D Layfield

Harutun G Karian

A centrifugal pelletizer has a hollow electrically and thermally conductive rotor with a series of orifices along its outer rim portion for centrifugally powering strands of heated thermoplastic material from a body of said material in a flowable state within the interior of the rotor. A knife mounted on the frame adjacent the rotor orifices severs the strands into pellets of a predetermined length. A molten material feed tube with fins therein at the exit end to divide the flow extends into a rotor housing to direct flow in a uniform manner to an axially opposite impeller on the rotor and control mechanism, sensitive to the temperature of the rotor adjacent the orifices, controls the supply of current to electromagnets, which have a peripheral magnetic flux conducting plate system extending to and forming a part of the housing creating a flux field which is interrupted by the spinning rotor to induce currents in the rotor which heat it according to the temperature sensed.

Centrifugally powered pelletizing machine and method

Uniform pellets of thermoplastic material are formed by centrifugally expressing strands of heated material from orifices on the rim of a hollow rotor and severing the strands with a linearly moving endless blade at a selected radial distance from the rim. The severed pellets pass in a tangential path through a cooling spray at the entrance to a pellet outlet duct. The severing blade is mounted on a bracket for movement to and from the severing position and for adjustment radially and circumferentially of the rotor axis. Two blade assemblies are employed alternately so that blade replacement may be accomplished without interrupting operation. Downstream from the outlet duct an auxiliary knife-gate is employed adjacent a scrap duct and is movable from a severing position to a scrap duct closing position.

Method of centrifugally pelletizing certain synthetic plastic materials

Centrifugal pelletizing systems and process

A rotor has a coaxial hollow casing with a plurality of concentric radially spaced sieves or screens therein. At least one light phase liquid inlet tube has communication with the radially outer portion of the rotor chamber, and at least one heavy phase liquid inlet tube has communication with the radially inner portion of the rotor chamber to supply light and heavy phase fluids, respectively to the chamber casing. The heavy phase liquid moves radially outward and is removed from the outermost portion of the rotor chamber while the light phase liquid moves radially inwardly and is removed from the radially inner portion of the rotor chamber. The machine is constructed with concentric, radially open distributor or dispersing trays within the rotor chamber communicating directly with each of the light and heavy phase liquid inlet tubes. Each tray includes an annular base wall with radially projecting walls projecting in the form of open ended risers which have large diameter passages extending through them, and which are surrounded by considerably smaller diameter passages in the base wall. The riser walls are of at least such radial extent as to collect a sufficient head of the phase being distributed to pass the phase to be dispersed through the smaller base wall openings under pressure of the tray 'head' developed, without countercurrent flow of the other phase through them. The riser openings provide flow of the continuous other phase (not being distributed) counter-directionally through the risers under the driving force of the head, and are sufficiently large to somewhat minimize appropriately the flow force at the riser openings and control the counter-directional flow.

Liquid-liquid centrifugal contacting machines and methods of

An improved system for treating material proceeding continuously through a processing barrel having at least twin interconnected cylinders with saddle portions of generally V cross section at the points of interconnection of the cylinders. Twin rotating parallel mixer shafts, co-axially mounted in the cylinders, have radially interwiping screw or paddle elements between a material charging inlet and a material discharging outlet which are configured to wipe the cylinders including the saddle portions. Sets of paddle elements, each of which includes a cylinder closing paddle, are provided on the shafts at a flow control station between the inlet and outlet, and a movable flow-controlling saddle or valve element is mounted with relation to the cylinder closing paddle sets in a position such that it can be moved from an opened position to a position to restrict or block flow past the sets of paddle elements. A vacuum vent port can be provided for degassing or like purposes in the barrel casing at the flow control station in a position in which its relationship with the elements is such as to avoid the flow of product out the port.

Multi-screw, continuous, material processing systems

A bowl type centrifuge for separating solids and liquids from mixtures in which the rotary differential speed between the centrifuge bowl and an internal conveying scroll is established by variably augmenting the frictional torque imparted to the bowl by the mixture driven in rotation by the scroll. The scroll is directly driven in rotation by a drive motor. The mixture to be separated is in turn driven in rotation by the rotating scroll and the frictional drag between the rotating mixture and the inner surface of the bowl induces rotation of the bowl. The speed of rotation of the bowl thus induced is less than that of the scroll, thus creating a rotary speed differential which enables the scroll to convey solid particles of the mixture axially toward one end of the bowl. The magnitude of this rotary speed differential is adjusted by a variable torque drive coupling between the scroll and bowl which may take the form of a variable speed fluid drive or an eddy current coupling to variably augment the torque transmitted to the bowl by the rotating mixture.

Growing community of inventors

Saginaw, MI, United States of America

David B Todd