Abstract: A differential screw adjusting mechanism comprised of an externally and internally threaded adjusting nut which has a plurality of slots formed along its length. The internal threads of the adjusting nut cooperatively and threadedly engage screw threads at the end of each of the expansion rods. The rods are in turn fixed to the lip of the die via set screws or jam nuts. A spool having an internally threaded diameter and a slot along its length is engaged to the external threads of the adjusting nut. The head of the spool has a flattened portion to limit rotation of the spool when clamped in place. Thus, the slotted adjusting nut is overfit with the slotted spool. The entire assembly of spool, nut, and rod is clamped in place via a clamping arrangement affixed to the die. The tightening of the clamp serves to close the spool via the slot over the nut, and in turn, the nut, via its slots, over the rod.

Abstract: A computer-aided method for predicting the layup of fiber-reinforced prepreg resin material for compression molding into three-dimensional shapes depends on the area relationships of the final thickness of the molded shape to the initial thickness of the prepreg material. A graphic display is generated incorporating the initial thickness needed at each location on the prepreg material to provide the desired final thickness of the three-dimensional shape with controlled fiber distribution throughout the shape.

Abstract: A method and an apparatus for controlling foam sheet blow-up in a thermoformer oven. Control of the oven operation is achieved through monitoring the measured blow-up of a material which being heated in the thermoformer oven in a forming station or thermoformer, such as by a linear variable differential transformer, in order to adjust the thickness of the plastic material by regulating the temperature of the oven prior to the conveyance of the material into the molding or forming station.

Abstract: The fleece spinning unit has a spinning nozzle system, a cooling shaft, a stretching aperture, a diffuser shaft, a continuously moving fleece receiving conveyor and a device for feeding process air and for drawing outflowing air through the fleece receiving conveyor. The cooling shaft has a shaft wall provided with a plurality of air orifices. Thus process air required for the cooling is fed into the cooling shaft and is at least partially drawn through the fleece receiving conveyor. The thickness of the spun fleece is measurable on the fleece receiving conveyor downstream of the diffuser shaft in the transport direction. A measured value/set-point comparison is made and on deviation of the measured value from the set-point the setting angles of opposing air control flaps which are located at the entrance of the stretching aperture are changed. On a positive deviation of the measured value of the thickness from the set-point the setting angle is increased.

Abstract: An improvement for casting machines is provided which assures a constant thickness and density of extruded material by varying the speed of nip forming rolls.

Abstract: A thickness control system for controlling the thickness of an extrudate includes a host computer for controlling the temperature of a heat responsive element based upon a predetermined temperature set point. A back-up duty cycle controller is provided for control in the event of host failure.

Abstract: A control system for controlling the edge thickness of an extrudate includes an arrangement responsive to a signal representative of the monitored thickness of the extrudate emanating from a die slot controlled by a transversely inward heating element for generating a control set point for that heating element and for a heating element controlling the die slot adjacent a lateral edge thereof.

Abstract: The process for making at least one thermoplastic monofilament of an exact diameter from a thermoplastic material by spinning in an apparatus in which a thermoplastic material is fed to at least one spinneret, which has at least one spinning plate with a plurality of spinning holes for the thermoplastic monofilaments, and forcing the thermoplastic material through the spinning holes with at least one spinning pump. To provide a monofilament of a very exact diameter the process further comprises measuring the diameter of each of the monofilaments in or after the outlet of the associated spinning hole, feeding the resulting measured value of this diameter as the actual value to a controller associated with that monofilament and controlling the flow rate of thermoplastic material through the associated spinning hole according to the difference between the actual value and a predetermined setpoint value.

Abstract: A pipe of thermoplastic polymer, e.g. polyvinylchloride is extruded by an extruder comprising an extrusion die (2) having a moulding end part (2a) with heating elements (11) located about said end part. The wall thickness of the pipe is controlled in order to obtain a pipe of a substantially even wall thickness. For said control the wall thickness of the extruded pipe is measured at 360 points equally distributed over the circumference and moreover the average is determined in eight measuring sectors comprising 45 measuring points per sector. The average of the measuring values of one measuring sector is compared with the circumferential average of the 360 points, the deviation of the desired wall thickness in said one sector being counter balanced by the action of the heating elements. In a preferred embodiment a polyvinylchloride pipe obtained by means of a two screw extruder presents an even wall thickness over the circumference.

Abstract: In a heat displacing type die adapted to extrude a sheet of molten resin, a heat displacing unit provided with a heater is secured to an upper die block. A lip gap is defined between a flexible lid and a stationary lip respectively provided for the upper and lower die blocks. The lower end of a bolt extending through the heat displacing unit is normally in contact with or secured to the flexible lip while the upper end is secured to the upper portion of the heat displacing unit. In a modified embodiment the bolt is air cooled.

Abstract: A coating method and apparatus using an extrusion head to apply a liquid film to a running web. The thickness of the film is measured at two transverse points and a roller conveying the web is tilted to correct any difference. The amount of tilt per roller with a roller bearing span of 750 mm is 0.5 to 20 mm, preferably 0.5 to 15 mm.

Abstract: An apparatus for adjusting the thickness of a resin plate formed in a resin plate making machine comprising stacked, wedge-shaped members, each wedge-shaped member having an inclined surface slidably contacting the other inclined surface, the top most member being connected to either spacers positioned above a rigid base plate on which the resin plate is formed, or to the rigid base plate itself, for adjusting the height of the spacers relative to the base plate as the wedge-shaped members are moved relative to one another in the direction of inclination of the inclined surfaces.

Abstract: A device for measuring the wall thickness of an extruded tube by means of ultrasonic pulses comprises a tube wall thickness measuring instrument being rotatable about the circumference of the tube and being connected to an arm extending in a plane perpendicular to the tube. The arm is hingedly connected in said plane to a ring perpendicular to the axis of the tube and concentrically about the tube. The arm bears a weight outside said ring. An adjustable pressure element, such as a spring or preferably a two way operable air cylinder, acts upon the arm.The measuring element may engage two supporting faces, the angle between the supporting faces being adjustable.Furthermore a detachable fixing element, such as a magnet, engages the arm so that the arm can be disconnected from the magnet and may be moved from the plane perpendicular to the tube.The wall thickness is measured only by means of one echo coming from the inner wall of the tube when an ultrasonic pulse emitted by the device hits said wall.

Abstract: A thickness control system for controlling the thickness of an extrudate includes a nested temperature control loop for controlling the temperature of a heat responsive element based upon a predetermined temperature set point. The temperature set point for the temperature control loop is computed based upon the measured thickness of the extrudate.

Abstract: A process of manufacturing a roll of continuous synthetic thermoplastic film consisting of extruded flat film or of extruded blow-formed and flattened tubular film in which the thickness of the film is measured over the width of the film. Any striplike portion which deviates in thickness from a means thickness of the film is adjusted. The temperatures of juxtaposed temperature control sectors or the width of those portions of the slot die or of the annular die from which said striplike portions have been extruded are adjustable. When a striplike longitudinal portion having a relatively large thickness is detected in the film, the film is subsequently extruded to have a corresponding portion which has a relatively small thickness within specified thickness limits and for a length such that the two portions as superimposed in the roll have an average thickness approximately equal to the mean film thickness.

Abstract: Extrusion apparatus for producing a continuous molten tube of a film-forming material includes an extrusion die defining an annular extrusion orifice between adjustable die lips through which a heat-plastified, synthetic, resinous, extrudable film-forming material is extruded in a radial direction. An annular gas bearing in spaced relationship to the orifice redirects the film into a tubular shape. In one die arrangement extrusion takes place radially outward, whereas in a second die arrangement extrusion takes place radially inward.

Abstract: An extrusion die having an adjustable lip opening through which thermoplastic material is forced to form a flat sheet. Fine adjustment of the lip is effected thermally and without play by the provision of an element or a heating or cooling block which braces the lip. Coarse adjustment is effected manually, and without play, by operation of a pair of bolts. One bolt axially shifts the block, and the other bolt tightens the block against the die body.

Abstract: A pipe of thermoplastic polymer, e.g. polyvinylchloride is extruded by an extruder comprising an extrusion die (2) having a moulding end part (2a) with heating elements (11) located about said end part. The wall thickness of the pipe is controlled in order to obtain a pipe of a substantially even wall thickness. For said control the wall thickness of the extruded pipe is measured at 360 points equally distributed over the circumference and moreover the average is determined in eight measuring sectors comprising 45 measuring points per sector. The average of the measuring values of one measuring sector is compared with the circumferential average of the 360 points, the deviation of the desired wall thickness in said one sector being counter balanced by the action of the heating elements. In a preferred embodiment a polyvinylchloride pipe obtained by means of a two screw extruder presents an even wall thickness over the circumference.

Abstract: Apparatus for producing plastic pipes by an extrusion process in which the wall thickness of the plastic pipe is controlled by the takeaway speed at which a soft plastic pipe is removed from a metal sizing sleeve. To measure the wall thickness of the soft plastic pipe advancing through the sizing sleeve for regulating the takeaway speed, a transducer emits ultrasonic sound through a plastic transmission line mounted in or on the sizing sleeve and interposed between the transducer and the plastic pipe. The time interval between the emission of a sonic pulse by the transducer and the detection of a reflected sonic pulse from the inner wall of the advancing soft plastic pipe is a function of the wall thickness of the plastic pipe in a soft plastic state.

Abstract: A thickness gauge traverse for a gauge such as a nuclear thickness gauge that measures thickness of extruded sheet at numerous locations across the sheet in a system utilizing those measurements to correct thickness of the extrusion. The traverse has a mount supporting the probe of the gauge for movement across the sheet. A motor and motor control electronics rapidly advance the probe from one measurement point to the next, where the mount is stopped permitting the probe to remain for the considerable time necessary to make its measurement without having that time dominate the speed of the gauge's movement from point to point across the sheet.

Abstract: A method for monitoring deviations in the dimensions of profile strips during production is disclosed, as is an apparatus suitable for carrying out the method. The profile strip is formed from one or more rubber or thermoplastics material mixtures which are fed from one or more extrusion devices through nozzles into a common nozzle in an extrusion head. Pressure and temperature measuring means measure the extrusion pressure and temperature of each mixture. The profile strip thus produced then passes over weighing device which measures its weight per unit length. The measured value is transmitted to a regulating or control device and compared with a desired weight per unit length.

Abstract: Method of adjusting the lip opening of an extrusion die for stratiform material, with the characteristic that it consists in the combination of, on the one side, the control of the heating of bar shaped elements (9) which act upon at least one of the lips (6-7) of the lip opening (5), in function of the thickness of the formed material, and on the other hand, the common cooling of several bar shaped elements (9) by forcing a cooling medium along these elements (9).

Abstract: A press having a stationary upper bolster and a movable lower bolster carried by two outer and two inner frame plates located near the ends and center of the platens respectively. Through the use of strain gauges measuring the load on the product provided on either sides of each frame plate and servo-operated piston cylinders connected to the lower bolster controlling the output force, a deflection of the lower bolster is made to be parallel to the deflection of the upper bolster so that an equal pressure distribution results in compression therebetween thereby producing a uniform thickness in the product.

Abstract: The shaping device, particularly for an extruder tool or calibrator unit, for an extruder for thermoplastic material comprises at least one outlet defining an adjustably positionable unit lip, an opposing lip and at least one positioning member acting on the unit lip which is a part of a control and/or regulating mechanism for the thickness of the extruded product. The positioning member is a piezoelectric translator connected to a voltage source having a plurality of piezoelectric disks positioned opposing each other which are combined in a plurality of groups according to operation and according to electrical circuitry considerations. The groups of the piezoelectric disks individually and the sum total of several of the groups including the group containing all of the piezoelectric disks are connectable to the voltage source.

Abstract: An apparatus for measuring the thickness of a tubular plastic layer during the process of its fabrication, which includes an ultrasonic transducer which generates a signal dependent on the thickness of the shape being measured while the shape is at a non-uniform condition of temperature, and circuitry for generating at least one signal from known process parameters, and an arithmetic unit for processing the signals derived as described above to generate an error signal which compensates for the influence of temperature on the test.

Abstract: A metal mold for resin molding of the type which comprises the combination of a fixed side metal mold assembly and a movable side metal mold assembly. Melt resin material is supplied into and filled in a cavity formed between the fixed side metal mold assembly and the movable side metal mold assembly, and pressure applied to obtain a desired mold thickness of a disk, etc. The metal mold for resin molding according to this invention further includes a spacer inserted between the ends of the guide post rods and the movable side metal mold assembly, to define a gap for adjusting the metal mold thickness.

Abstract: Apparatus for forming an insulation layer around an electrical conductor and having a die insert or core tube for guiding the conductor through a die orifice. The insert is movable to control its position and its position is controlled by two rotatable mountings. A first of the mountings eccentrically holds and is rotatable around the insert while the second mounting lies radially outside of and eccentrically holds the first mounting. A monitoring means analyzes degree of eccentricity of the conductor and operates a driving means for the mountings to move the insert in the appropriate direction for concentricity.

Abstract: Extrusion apparatus for conductor wire in which a core tube for guiding the wire is controllably movable axially so as to adjust the cross-sectional area of the flow passage for molten polymeric dielectric material moving towards the die orifice. The use of the adjustable core tube minimizes the degree of draw down of the conductor wire.

Abstract: Apparatus for spinning monofilaments made of thermoplastic synthetic resin, with a spinning head for monofilaments, at least one spinning panel with a plurality of nozzle orifices, one or more spinning pumps with a motor equipped with a regulator for controlling the thickness of the monofilaments. The regulator can be fed to the diameter measurements of the individually measured monofilaments. Anywhere from 6 to 60 nozzle orifices, preferably about 20 nozzle orifices, are combined into a nozzle orifice group. Each nozzle orifice group has its own spinning pump with its own regulator. The monofilaments of the nozzle orifices of a nozzle orifice group can be conducted past a measuring device for the measurement of the diameters of the monofilaments. This measuring device will calculate an average of the diameter measurements of the monofilaments, which can be fed as an actual value into the regulator which services the spinning pump of the corresponding nozzle orifice group.

Abstract: A T-die adapted for extrusion molding of a plastic material such as plastic film is constituted by a lower stationary half and an upper movable half. The stationary half is integrally provided with a steady lip portion and a movable half is provided with a base portion and flexible lip portion so as to form a gap in slit form between the steady and flexible lip portions. The gap is adjusted partially by a plurality of adjusting bolts screwed to the upper portion of the movable half extending to cover the flexible lip portion with space, the bolts being arranged in a line along the longitudinal direction of the T-die and spaced equally with each other. Each bolt has such a length that the front end thereof downwardly presses the flexible lip portion when the bolt is driven downwardly. The flexible lip portion is provided with a plurality of U-shaped grooves each disposed between the adjacent two bolts and having a width of an opening substantially equal to the distance between the adjacent two bolts.

Abstract: A process is provided for controlling a thickness regulating member such as a slice lip coupled to slice rods. The process includes determining the desired configuration of the slice lip and determing the required slice rod movements based upon physical characteristics of the slice lip and the slice rods.

Abstract: The thickness of the barrier layer in coextruded multilayer, thermoformable resinous sheet material is controlled by transverse color monitoring during coextrusion of the sheet.

Abstract: The present invention teaches a method and apparatus for controlling the size of an opening through which material is metered by generating energy in the form of a magnetic field close to an element which forms an integral part of the metering device, the element movable relative to another member. The method and apparatus can be utilized for controlling a desired physical property of a product which is dependent on the metering operation, such properties as basis weight, caliper, density, bulk, reel hardness, gloss, smoothness, and opacity, of interest in the paper, plastics and coating fields.

Abstract: The invention relates to a continuously operating press for pressing an advancing web of material, comprising a rigid press frame, an upper and a lower endless press belt, each guided over a pair of deflection rollers mounted for rotation on the press frame, comprising a heating device to heat at least one deflection roller of each pair, comprising a reaction zone located between the upper and lower press belt strands facing each other for pressing the advancing web of material with the simultaneous application of heat, and comprising pressure plates with a heating device at the rear sides of the press belt strands remote from the reaction zone for exerting a pressure on these rear sides and, consequently, on the web of material.

Abstract: Providing an insulation layer upon electrical conductor by passing the conductor with clearance towards and through an outlet orifice of a die insert as the conductor approaches a die orifice. The degree of concentricity of the conductor within the insulation layer is monitored after extrusion and an eccentrically positioned conductor is moved towards a concentric location by moving the conductor, at a position upstream of the outlet orifice of the die insert, laterally of the feedpath. This movement effects a change in approach of the conductor to the outlet orifice and influences a change in the angle of departure from the outlet orifice thereby altering the lateral position of the conductor within the die orifice.

Abstract: A die for a thermoplastic material with at least one output-gap-defining adjustable die lip, an opposing gap-bounding lip, at least one adjusting element working on the output-gap-defining die lip as well as a control and adjusting device for the thickness of the extruded plastic product, wherein the adjusting element is associated with and operated at least partially by the control and adjusting device. A field translator, either a piezotranslator or a magnetostriction translator, is employed as the adjusting element.

Abstract: An extruder press unit for extrusion of a thermoplastic material has at least one output gap in an extruder body, wherein the output gap is formed by an output gap-defining adjustable extruder lip and an opposing gap-bounding lip. This output gap is adjustable with the help of a mechanical coarse adjusting mechanism to a given gap width, and the gap-defining adjustable extruder lip is connected to at least one adjusting element, to which a control and adjusting device for the thickness of the extruded material is associated. The opposing gap-bounding lip is likewise constructed as an adjustable structural component. The coarse adjusting mechanism operates on the opposing gap bounding lip. A field translator is employed as at least one of the adjusting elements and of course in the form of either a piezotransistor or a magnetrostriction translator. The control and adjusting device is set up for a fine adjustment in the range between 0.05 and 0.3 mm, preferably between 0.10 to 0.20 mm.

Abstract: A device for adjusting the height of building blocks or similar, which operates to form inside a mold blocks the height of which varies between a predetermined height and a height which is lower than the predetermined height, laying over the blocks an amount of material the height of which is higher than the height difference between the predetermined height and the actual height of the blocks, and levelling the material amount until the total height of the blocks as formed by the sum of the actual block height and the height of the material amount substantially corresponds to the predetermined height.

Abstract: A machine has a nozzle formed with an annular passage centered on an axis and having at an outer axial end an annular mouth. A plastic mass is introduced under pressure into the inner axial end of the passage at two diametrally opposite locations and mixes and passes outwardly along the passage to emerge from the mouth as a tube. The axial outward flow of the mass along the passage is impeded upstream of the mouth to pressurize the mass with a pressure substantially greater than atmospheric. Such flow is impeded either by restricting the passage or by allowing the volume of the passage to increase against a predetermined counterforce. The mass will form when it leaves the nozzle a tube of almost perfectly uniform wall thickness.

Abstract: An extruder is controlled in response to the thickness measurement of the extruded strand. The thickness measuring head is initially given a displacement transverse to the extrusion direction, preferably around the extruded strand and the output signals from the head are integrated to form a mean value around the periphery. A comparison of this mean value with the set point wall thickness value is then utilized to provide continuous correction of the output of the head which is utilized to regulate the extruder operation.

Abstract: Apparatus is disclosed for the formation of pipe comprising one or more layers of thermoplastic resin. The apparatus comprises a die housing having a bore therethrough with a mandrel longitudinally supported within the bore by radial members extending from the inside surface of the bore to provide an annular extrusion passageway defined by the inside surface of the housing and the outer surface of the mandrel. The housing includes therein a plurality of electrically resistive heating elements longitudinally positioned parallel to the extrusion passageway to selectively heat the thermoplastic material flowing therethrough in proximity to the heated section thereby increasing the laydown of thermoplastic material. Also included in the housing is plurality of radially adjustable elements having electrically resistive heating elements therein to radially reposition a moveable discharge sleeve held therebetween thereby controlling the wall thickness of the thermoplastic material passing in proximity thereto.

Abstract: Four ultrasonic probes in space quadrature are located near the input end of a water tank to define an opening for receiving extruded plastic tubing provided from an adjacent extrusion die. The probes are formed with passages that expel bubble-free water between the probes and tubing. Ultrasonic thickness measuring circuitry provides a wall thickness signal to a control signal source that also receives a diameter signal provided by a diameter sensor near the output end of the tank representative of the tube thickness.

Abstract: An improved extrusion die employing proximity sensors to directly measure the actual die gap during extrusion is disclosed. The proximity sensor may be a capacitance-effect, or optical-effect sensor. Manual and automated closed-loop methods of operation are also disclosed.

Abstract: A method of monitoring the production of extruded composite profiles by an extrusion head fed by a plurality of worm extruders in which, immediately after the profile has been extruded, it is monitored by spacing measurement devices which determine the spacing between the devices and the profile. The measured spacing is then transmitted to a regulator or governor and compared with a pre-selected value. The governor or regulator controls the worm speed of the individual extruders and, if the measured value differs from the pre-selected value, alters the worm speed of one or more of the individual extruders until the measured value is the same as the pre-selected value.

Abstract: An apparatus for adjusting die clearance for an extruder producing a sheet in a die having an adjusting device for adjusting the die clearance between an upper die and a lower die, a measuring device for measuring thicknesses of the sheet at a plurality of positions in the direction of width on the sheet, a setting device for setting desirable thicknesses at the positions, an adjusting data producing device for producing data with respect to die displacement to be adjusted from the measured data and the desirable thicknesses, and control device for controlling the adjusting device in order that the die clearance coincides with the desirable thickness. Rough adjustment can be effected by tightening or loosening the bolts while fine adjustment is achieved by heating the bolts with an electrical heater disposed thereabout.

Abstract: A method and apparatus for controlling the average thickness (T.sub.1) of a film lamina of thermoplastic, dielectric material having a known density (D.sub.1) and coextruded at a variable extrusion rate with a foam lamina of similar thermoplastic material having a thickness (T.sub.2) and the density of (D.sub.2) to form a thermoplastic laminate is disclosed. The apparatus comprises a first gauge for sensing the thickness of the laminate and for providing a caliper signal (C) corresponding to the thickness sensed and a second gauge for sensing the mass/unit-area of the laminate and for providing a mass signal (M) corresponding to the mass/unit-area sensed. The apparatus further comprises a third gauge for sensing a response to the dielectric material and its distribution in the laminate and for providing a dielectric signal (W) corresponding to the response sensed.

Abstract: A process is disclosed for the formation of pipe comprising one or more layers of thermoplastic resin whereby an annular stream of thermoplastic material is transported through an annular extrusion passageway. The downstream annular portion of the extrusion passageway has a radially movable outer wall. The outer wall is radially moved by heat expansion of a bolt thereagainst to change the thickness of a particular arcuate section of the stream. The thickness of the particular arcuate section of the stream may be further changed through selectively heating by electrical resistive elements an arcuate section of the extrusion passageway to heat the stream of thermoplastic material transported in proximity thereto.

Abstract: A web manufacturing apparatus including a flexible shaping member that engages fluid material of which a web is formed, a support that extends parallel to the shaping member and a plurality of thermal expansion rods that extend between the shaping member and the support so that the shaping member can be flexed to control the web thickness profile by means of heaters on the thermal expansion rod. Each thermal expansion rod is fixed to the shaping member and is secured to the support via a differential screw mechanism that includes a driven screw and an adjusting screw positioned in tandem in a threaded bore through the support and are coupled so that the driven screw can be turned by turning the adjusting screw. The driven and adjusting screws have internally threaded bores and one end of the thermal expansion rod screws into the bore of the driven screw.

Abstract: An apparatus for producing a composite pipe having a desired wall thickness by using an endless steel belt as a mold which moves axially while rotating in the circumferential direction of a mandrel. In this apparatus, a thickness regulating device spaced a predetermined distance from the outside surface of the endless steel belt is used to adjust the wall thickness accurately to the desired value. Examples of the thickness regulating device are a cylinder roll, a taper roll, and a conveyor belt.

Abstract: A dough shaping, dividing and reshaping machine has a feed conveyor for conveying a batch of dough to preshaping means including laterally spaced side rollers and vertically spaced top and bottom rollers and other rollers for advancing the batch to a dough divider means for receiving the dough batch in a preshaped configuration, shaping it to two generally rectangular cross section strips of dough and advancing the strips to a cut-off location, dough cut-off knives at the cut-off location for dividing the two strips alternately into parts of determinable size, separating such parts in sequence from the strips and delivering them individually to a dough forming means for receiving the individual dough parts and forming them into toroids or alternatively into dough balls of various sizes; roller means are provided for sensing the buildup of the dough batch between the top and bottom roller and the dough divider means; and an electric drive is provided for varying the advancement of the dough batch by the advanc