摘要:
Apparatus for producing, from rubber and/or plastic mixtures, thin wall tubes for bicycle and motorcycle tires includes an extruder followed by a belt conveyor for transporting the extruded tube blank from the extruder, a scale for weighing the tube blank, another belt conveyor, rolls for forming the blank to a predetermined cross sectional shape and a light source on one side of the tube blank and a light receiver on the opposite side of the tube blank for measuring a transverse dimension of the shaped tube blank and thereby its circumferences. A blower supplies to the interior of the tube blank a mixture of air and powder which is removed by an exhaust blower which is regulated to control the air pressure in the tube blank. The rate of withdrawal of the tube blank from the extruder by the conveyor and the air pressure inside the tube blank are controlled by outputs of the scale and the transverse dimension measuring light receiver.
摘要:
An extrusion head having a stationary part fixed on an extrusion installation having a plurality of extrusion cylinders supplying an extrudate formed from several components. The stationary part has extrudate flow channels each in communication with a respective extrusion cylinder and a common extrusion die. Two pivotable outer parts pivotally hinged on the stationary part are selectively swingable individually between open and closed positions by respective piston-cylinder units. The two outer parts define an extrusion orifice for the die in their closed position. A pair of locking piston-cylinders provided with hammerhead piston rods hold the respective outer parts clamped against the stationary during an extrusion. Actuator piston-cylinder units selectively swing the piston rods of the locking piston-cylinder units clear of the outer parts for opening them for cleaning extrudate channels or for an extrusion die change. Two pivotable inner parts between the outer parts and the stationary part define extrudate channels jointly with outer parts and stationary part and are selectively swingable by a respective piston-cylinder unit and exposing corresponding flow channels of the stationary part for cleaning when the outer parts are open. The inner parts have lateral flanges with a respective recess into which is inserted a retainer piston rod of a corresponding piston-cylinder unit to retain the respective inner part closing a respective stationary part flow channel against residual extrudate in the absence of extrusion of extrudate therethrough.
摘要:
The invention relates to a process and apparatus for processing elastomeric material in particular plastic, rubber and a mixture thereof in roller-head-apparatus in which the material to be processed is plasticized and homogenized in an extruder, extruded from an extrusion head provided on the extruder and then is led through an aperture formed between two rollers. It is the object of the present invention, with an especially simple extrusion head in a roller-head-apparatus to produce uniform and dimensionally exact sheets or foils of different thicknesses without changing structural parts. The invention achieves this in that material formed in plate form by parallel outlet surfaces of the extruder head is led through an aperture space formed between a concave cylindrical surface of a stationary forming tool and the circumferential surface of one of the rollers of the calender before the material enters the space between the two calender rollers.
摘要:
A screw extruder, for use with or without a calender, has a divided or split extruder head with upper and lower parts or halves hingedly mounted on a collar secured to a flange at the discharge end of the extruder cylinder. Each of the upper and lower extruder halves is movable between an open innoperative position and a closed operative position by a piston cylinder unit acting between a fixture on the respective extruder head part and a fixture on the extruder cylinder. When in closed position, the upper and lower extruder head parts or halves are pressed toward one another by a pair of vertical piston-cylinder units, each having a cylinder with lower end engaging the upper extruder head part and a projection on a piston rod engaging the lower extruder head part. The vertical piston-cylinder units are mounted on pivoted carriers mounted on the collar on the extruder cylinder. The two carriers are interconnected by a horizontal piston-cylinder and are also movable vertically. Operation of the apparatus is effected by an electro-hydraulic control circuit having a processor by which sequential operation of the piston-cylinder units is controlled.
摘要:
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. Hydraulically operated clamps hold the movable main part in closed position and a hydraulic servo motor exerts on the movable main part a force parallel to the forward face of the stationary main part and directed toward the abutment. In one embodiment, there are two movable main parts pivoted at opposite sides of the stationary main part and having an extrusion die unit between them.
摘要:
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.
摘要:
Rubber hose with textile thread reinforcing is produced by extruding an inner tube of rubber material, cooling the extruded tube, applying a covering of textile thread over the inner tube and then extruding an outer layer of rubber material over the textile layer. Just before the outer layer is extruded on the inner tube it is heated by subjecting it to an ultrahigh frequency field. The outer layer is extruded on under a vacuum so that the inner tube which has been softened by the UHF heating is supported by the resulting pressure differential. The resulting hose is then vulcanized. By reason of the preheating of the inner tube, the inner and outer rubber layers are at approximately the same temperature and hence vulcanized equally. The application of a vacuum during the second extrusion has the further advantage of avoiding air inclusions between the inner and outer rubber layers.