Abstract: A screw-type extruder in which the wall of the cylinder receiving the screw has an annular recess which is disposed in a radial region of a core bead of the screw and pins extend through this recess and are diagonally inclined to the radial plane thereof close to the circumference of the bead.

Abstract: Process for producing from a rubber mixture blanks for finished parts in the rubber industry is composed of an extruder having a cylinder and a screw rotatable in the cylinder to plasticize a rubber mixture fed into the cylinder, an extrusion head and a gear pump between the extruder and the extrusion head for producing extrusion pressure and forcing the mixture through the extrusion head at a predetermined rate per unit time to form a uniform strand of predetermined shape which is cut into uniform lengths.

Abstract: An extrusion head for sheathing elongate objects such as cables has a housing with an elongate bore in which there is a hollow mandrel through which is passed the object to be sheathed. At the discharge end of the mandrel there is a forming tool made up of an annular forming tool part on the mandrel and a concentric forming tool part at the adjacent end of the bore of the housing. An extruder connected to the extrusion head housing forces sheathing material into the bore of the housing and out through the forming tool to form a sheath on the cable or other object as it is passed through the hollow mandrel. A rotor which is rotatable on the mandrel has a screw thread web of decreasing height for propelling sheathing material toward the forming tool. There are lubricated radial seals between the rotor, mandrel and housing. For applying a double layer sheath, there are two entrusion heads interconnected one behind another and supplied with sheathing material by two extruders.

Abstract: A screw extruder having a barrel with a longitudinal bore for receiving a rotatable screw, a transverse bore disposed in the barrel tangential to the longitudinal bore for receiving and supporting a pin wherein the pin extends partially into the longitudinal bore. The tangential arrangement of the pin substantially decreases the susceptability of the pin to bending or breaking. The pin may also be adjustably positioned in the transverse bore and further may be subject to thermal heating and cooling.

Abstract: Apparatus for extruding plastic and/or rubber material has a screw extruder, which plasticizes the material and delivers it to a gear pump which develops sufficient pressure for extrusion of the material through an extrusion head. The apparatus is characterized by the fact that the axes of gears of the gear pump and the axis of the screw of the extruder are parallel to one another. The housing of the gear pump has a side opening into which a cylindrical bushing and the screw of the extruder extend so that the material is delivered by the extruder directly to the gear pump as a non-oriented plasticized mass. The extrusion head may be a transverse extrusion head with an axis parallel to the axes of the gear wheels of the gear pump and the axis of the screw of the extruder. A second like extrusion apparatus including a screw extruder and a gear pump may be connected to an opposite side of the extrusion head.

Abstract: A screw extruder has a feed roller which is parallel to and spaced laterally from the screw, a hopper feeds the material to be extruded to the screw and feed roller and to the space between them. A knife scrapes material from the feed roller to keep it clear. In one embodiment, the knife is pivotally supported by a knife holder disposed below the feed roller and is pulled against the feed roller by a spring-loaded link which is pivotally attached to a median portion of the blade. In another embodiment, the knife is a flexible spring blade. A protuberance on a knife-holding plate limits flexing of the blade by pressure of material in the space between the screw and the feed roller. In a further embodiment, a photo-cell scans a rear side of the feed roller and controls a servo-motor for drawing the knife against the feed roller.

Abstract: A cable made up of a plurality of conductors twisted together is drawn through the extrusion head of an extruder which applies a sheath of plastic or elastomeric material to the cable. From the extruder, the cable passes through a tube having a heated section in which the sheath material is cured followed by a cooling section. The sheathed cable is rotated about its axis to twist the cable. Guide wheels over which the cable passes have on their circumferences a multiplicity of pairs of rollers which are engaged by the cable and have their axes tangential to the circumference of the wheel so as to support the cable while permitting rotation of the cable about its axis. In one embodiment, a device for drawing the cable from the extruder, while twisting it, has a pair of endless belts which grip the cable between them and a motor for driving the belts. The belts and driving motor are mounted in a motor driven rotatable cage which rotates about the axis of the cable.

Abstract: A gear pump for pumping viscous material has a housing with an inlet and an outlet and a gear chamber between the inlet and the outlet. A pair of intermeshing gear wheels which are rotatably supported by bearings in the gear chamber of the housing have end faces in rotative contact with abutting faces of the housing. Spiral grooves in end faces of the gear wheels have a direction to move radially outwardly any material entering between end faces of the gear wheels and abutting faces of the housing to prevent such material from reaching the bearings. An integral drive shaft of one of the gears has a helical groove for preventing material from reaching bearings of the drive shaft. The driven gear has a central circular recess in which a bearing stud projects with bearing needles between the stud and the recess in the gear.

Abstract: Screw extruder for working plastic compositions, especially polymers and rubber mixtures having a cylinder in which a motor-driven screw is disposed. The cylinder being provided with pins which are disposed in planes perpendicular to the cylinder axis and can be pushed radially through openings in the cylinder wall, and the screw being provided in the pin planes with gaps in the screw spirals. The object of the invention is to create a practically achievable and economical possibility for the shifting and depth adjustment of pins in screw extruders. A plurality of pins, lying in an axis parallel row, are fastened to a beam at the extremities projecting from the extruder cylinder.

Abstract: An extruder has a screw rotatable in a housing and an extrusion head having an upper part bolted to the housing and a lower part hingedly connected to the housing for movement between a closed operative position and an open position. The upper part of the extrusion head is located above the screw so that the screw can be removed from the housing when the lower extrusion head part is swung to open position and without removing the upper extrusion head part from the housing. The two extrusion head parts define between them a flow passage directed toward the upper roller of a calender. A movable lip on the lower extrusion head part faces, and is spaced from, the upper calender roller to define a variable gap through which extruded material must pass before reaching the narrowest part of the gap between the calender rollers. The lip is either pivoted at an upper edge or is slidable toward and away from the upper calender roller to vary the width of the gap formed between the lip and the upper calender roller.

Abstract: An extruder head for producing profiles of rubber and/or plastic mixtures has a stationay main part which has a forward face in which the discharge ends of at least two extruders, rigid with the stationary main part open. The stationary main part has a transverse pivot shaft at one side of the forward face and, at the side opposite the pivot shaft, an abutment which projects forwardly of the forward face. A movable main part is pivoted, with play, on the pivot shaft and is swingable between a closed position in which it overlies the forward face and an open position. An extrusion die unit is disposed between the outboard end of the movable main part and the abutment. Flow channels between the movable main part and the stationary main part lead from the extruders to the extrusion die unit.

Abstract: The invention relates to an apparatus for treating objects with UHF-engergy comprising an elongated treating chamber, which is provided with UHF traps at entrance and exit ends, through which a conveyor runs and on its upper side is provided with UHF energy inputs which are connected by waveguides with their energy source, whereby parts of the upper side of the treating chamber are formed as hinged or removable covers. It is the object of the invention to provide an apparatus for treating products with UHF-energy which with simple construction permits an opening of the treating chamber from above over its entire length. The invention consists therein, that also those parts of the upper side of the treatment chamber which are provide with UHF inputs are formed as hinged or removable covers and that the waveguide leading from the UHF energy source to the UHF inputs to the treating chamber is formed flexible or comprise at least two separable parts.

Abstract: Apparatus for manufacturing lengths of rubber hose of curved shape comprises means for feeding a sequence of flexible mandrels in end-to-end relation to and through a first extruder which extrudes a continuous rubber hose onto the string of mandrels. Downstream of the extruder there is means for wrapping reinforcing thread around the hose and a second extruder for extending a second layer of rubber onto the reinforced hose. Downstream of the second extruder the hose is cut at locations between successive mandrels to form separate lengths of hose each with a flexible mandrel therein. Clamping means engages opposite ends of each mandrel with a hose length thereon and forces the ends toward one another to bend the mandrel and hose to curved form. While thus held in curved form, the hose lengths are vulcanized. The mandrels are then removed while evacuating the interior of the mandrel to contract it and forcing pressure fluid between the mandrel and the curved hose length to facilitate the removal.