Abstract: An open tube apparatus and method for continuously producing a rotating elongate strip of material are disclosed. An extrusion die continuously extrudes flowable material to form an open tube with a central longitudinal cavity and a transport mechanism includes a plurality of drive rollers which engage and pull the tube downline. A driver rotates the extrusion die and transport mechanism. A tube cutter, which is offset at an angle with respect to the downline direction and defines the open end of the tube, cuts the tube into a continuous elongate web of the desired width as the tube moves downline. An air seal seals the tube cavity to prevent air from escaping through the open end of the cavity, and a tube pressurizer controls air pressure in the central longitudinal cavity of the tube to expand the tube laterally outwardly.

Abstract: A method of producing a multicomponent extrudate in which the operating line automatically and accurately extrudes the extrudate materials necessary to obtain the desired contribution of materials and specified dimensions of the multicomponent extrudate profile. The screw speed of each extruder can be adjusted to the desired speed by determining the actual thickness and width dimensions of the multicomponent extrudate. The actual measurements are then fed to a computer which calculates the corresponding values of the ratios of the extruder screw speeds to line speed. using the specified dimensions desired in the extrudate, the corresponding values for the screw and line speeds are also calculated. A comparison of the speeds based on measured dimensions, with the speeds based on specified dimensions, provides a measurement by which the screw speeds may then be adjusted such that the measurements of the extrudate profile are brought closer to the specified dimensions of the multicomponent extrudate profile.

Abstract: An improved plate flatness control method adapted to effect a control so that plate flatness of a rolled material is made optimum by adjusting manipulated variables. In determining correction quantities of the manipulated variables, under the constraint that upper and lower limits exist in at least one of the manipulated variables and the correction quantities, a weighted square sum of deviations of a plate flatness distribution in the width direction of the rolled material is taken as an objective function to determine, using a non-linear programming, correction quantities of the manipulated variables where the objective function becomes minimum, thus, to control the plate flatness of the rolled material on the basis of the determined correction quantities of the manipulated variables.

Abstract: An extruder has a housing, a core centered on an axis, and a sleeve spacedly coaxially surrounding the core and defining therewith an outlet passage. Thus molten material emerges from the passage as a tube. A plurality of radially extending and angularly spaced adjustment screws are threaded into the housing and radially engage the sleeve so that these screws can be screwed in and out to radially displace the sleeve on the housing and thereby adjust the passage. A detecting unit axially downstream of the extruder includes at least one sensor for measuring the thickness of the tube at a plurality of angularly spaced locations and for producing an output corresponding to the respective measured thickness. An adjustment unit including at least one rotary tool engageable with the screws can selectively rotate same and screw same in the housing.

Abstract: A device for flat-rolling a ball of dough to obtain a sheet of dough which has substantially straight front and rear edges. The device includes a framework for rotatably supporting a pair of rolls through which the ball of dough is passed, the rolls being supported such that they may move towards and away from each other, a biasing means being present to press the rolls towards each other, the biasing means being including at least one pressurized fluid cylinder to which pressurized fluid is supplied in such a way that in case of varying resistance of the dough a virtually constant opposing force is exerted onto said dough.

Abstract: An apparatus for controlling the thickness of a film molded by a melt extruding method provided with a plurality of cooling means for cooling the vicinity of a die lip close to a plurality of heating means and with many grooved holes in which the heating means are embedded and provided with air holes at the both ends thereof, whereby the temperature can be freely adjusted to the high and low set values in a short period of time, by which the time loss and material loss can be reduced.

Abstract: A method and apparatus for producing an article, by covering at least a portion of a microwave heatable former with a liquid-containing material, applying microwave radiation to heat the former so as to leave a dry solid coating on the former, and effecting relative separation between the former and the dry solid coating so as to produce the article.

Abstract: A method for controlling the manufacturing process in the continuous prodion of gypsum-cemented workpieces utilizing a belt-type press or similar equipment including a number of press segments joined in tandem relationship. Utilizing this press, the gypsum undergoing hydration is compacted until the end of the hydration is reached. The swelling pressure created in the course of the hydration is measured and utilized to control the manufacturing process.

Abstract: A foil-blowing apparatus has at least one deformable lip defining the annular orifice from which the thermoplastic tube which is blown to form the coil is extruded. The lip can be provided with an array of effectors which, in response to a thickness-profile measuring unit, can radially deform the lip to correct thickness errors. The lip can be under prestress and the radial deformation is effected by measuring the thickness and superimposing a radial force on the prestress.

Abstract: A dough-stretching roller apparatus is provided to produce a continuous web of dough in a process to manufacture confectionery and bread. The apparatus includes a pair of upper rollers, a sensor means that detects the width of dough at the gap between the upper rollers, and a controller that controls a motor driving the upper rollers in response to a signal from the sensor means. The controller decreases the rotational speed of the upper rollers when the sensors detect that the width of dough is broader than a predetermined width of dough passing through the upper rollers, while the controller increases the rotational speed of the upper rollers when the sensors detect that the width of dough is narrower than the predetermined width of the dough passing through the upper rollers. Thus, even if the amount of dough supplied from a hopper is unstable, production of a stretched web of dough having a constant volume per unit length can be stably continued.

Abstract: An improved adjustable diehead assembly for mounting on a plastic extrusion machine is described. A discharge orifice for a parison of plastic is formed by a mandrel and annular member. The annular member is moveable by a holder assembly perpendicular to axis of the mandrel to adjust the orifice. The holder assembly includes cams which act upon the opposed sections of the outside surface of the annular member to adjust the orifice when first and second screws are tightened. A third screw acts upon the annular member to adjust the orifice. The screws are mounted on a front part of the holder assembly on the diehead to allow adjustment of the orifice even when the extrusion machine is operating.

Abstract: Platelike webs of thermoplastic material are produced by extruding a strip of the thermoplastic material and passing it through a roll unit having a pair of intake rolls upstream of which a bank of the material is formed. The delivery speed is controlled in response to the bearing pressure of the intake rolls.

Abstract: An apparatus for measuring eccentricities of a rod of plastic material extruded from an extruder includes an optical sensor arrangement having a central axis, the arrangement including a pair of optical sensor devices circumferentially spaced at 90 degrees to one another about the central axis and a pair of light sources disposed on sides of the central axis opposite to the respective optical sensor devices for providing shadows of the rod on the optical sensor devices. A mounting fixture supports the sensor arrangement with its central axis aligned with the nozzle axis of the extruder so that the extruded rod will travel along the central axis of the sensor arrangement. An output device is connected to the sensor devices for measuring deviations of the shadows from predetermined positions indicating concentricity of the rod.

Abstract: A device for producing hollow plastic pipes having a predetermined wall thickness, includes an extruder for producing soft hollow plastic tubing from a raw material, a continuous cooling chamber disposed downstream of the extruder for hardening the soft hollow tubing into the desired plastic pipes after the wall thickness of the plastic tubing has been calibrated, an independent water cooled calibrating sleeve disposed between the extruder and the cooling chamber which adjusts the wall thickness of the soft hollow plastic tubing, the water cooled calibrating sleeve being separated from the extruder and the cooling chamber, and a thickness measuring device disposed in the gap between the calibrating sleeve and the cooling chamber. The calibrating sleeve has an inner wall in which are arranged water inlets and suction orifices distributed along the circumference and the length of the inner wall.

Abstract: For producing a multi-extrudate of thermoplastically processable plastic, a coextrusion adapter block has a multi-part slide having a plurality of side-by-side slide sections mutually spaced in a direction transverse to the flow direction and slidably fitted in the adapter block for movement to adjustably protrude into a secondary runner for adjusting the thickness of a molten extrudate therein. A multi-layer extrudate emerging from the adapter block is further extruded in an extrusion die, and the thickness of at least one layer thereof is measured at a plurality of positions along the width thereof. The width measurements are used to control the positions of corresponding slide sections so that the layer thicknesses can be accurately controlled during an extruding operation.

Abstract: Pressure rollers are carried on respective shafts which are slidable in slotted plates towards and away from a machine centreline to define a gap. Measuring means are provided for determining the position of each roller, in the form of a contact probe mounted on each end of each shaft with the probes at either end bearing on opposite faces of a plate of known thickness centred on the machine centreline.

Abstract: A method for extruding silicone tubing which maintains consistently precise dimensions in the final tubing product by continuously monitoring the tubing profile after cooling and adjusting the height the loop of uncured tubing as necessary to neck the tubing down to the desired size.

Abstract: 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.

Abstract: In an apparatus for use in carrying out decoupling control of a T-die which has a pair of lip portions with a gap extended between the lip portions and with the lip portions divided into a plurality of zones individually driven by driving devices, respectively, a processing circuit individually controls the driving devices by the use of a predetermined decoupling control algorithm. The predetermined decoupling algorithm is given by a plurality of desired displacement vectors of the gap for the respective zones and a decoupling control matrix defined by inverse numbers of products of a command value/driving pressure converting matrix (Kp) and a driving pressure/displacement converting matrix (K.alpha.). Alternatively, the decoupling control matrix is repeatedly modified with time to decrease a difference between the desired gap displacement (.DELTA.y) and the measured gap displacement (.DELTA.y.sub.m). Each command voltage value vector .DELTA.

Abstract: An improved apparatus for controlling a plurality of die lips arranged in the direction of width of an extrusion molding die through which molten resin is extruded in the form of a sheet (or a film) so as to allow the die lips to be displaced back and forth. The apparatus includes a plurality of stud bolts fastened to the die lip with each bolt having a flange portion for holding Belleville springs which are received below the flange portion of the stud bolt. An arrangement is provided to compress the Belleville springs which includes plurality of adjustment bolts.

Abstract: An apparatus for the continuous manufacture of high temperature superconducting wires is disclosed. A core on which the superconductive ceramic substance is caused to directionally solidify from the melt is drawn through the melt in such a manner as to obtain an oriented microstructure conductive to high critical current carrying capacity. This also produces a macrostructure with appropriate mechanical strength and flexibility independently of the superconducting substance chosen.

Abstract: An extrusion die head for producing multiple layer tubular plastic bodies is disclosed in which the size of the tubular resin flow passage for at least one of the resin layers is infinitely adjustable at the point where two or more resin layers merge together to form a multiple layer stream. The adjustable passages are formed by two spaced inclined surfaces at the downstream end of the passages. The thickness of the passages is varied by axially moving one surface relative to the other. The moveable inclined surface is carried on an annular ring member mounted in the die head. In one embodiment, the ring is replaceable with another ring member to axially move the surface, thereby adjusting the layer thickness. In another embodiment, the ring member is threadably mounted in the die head so that rotation of the ring causes axial movement of the surface to adjust layer thickness.

Abstract: A method of apportioning the quantity of material in the manufacture of molded products made from hardenable molding compounds in which a resin mat panel is cut into individual cut pieces which are stacked into mat packets and fed to the tool of a parallelism controlled press equipped with a path measuring system for measuring the distance between the clamping plates. The mat packets are compacted to become the molded products. A constant molded product volume is realized by measuring the thickness of the molded product at a defined point in time by means of the path measuring system and the measured values are used as regulating values for regulating the size of the cut area of each cut piece.

Abstract: There is disclosed a film thickness controller which contains a large dead time and in which, in order to solve a problem due to the dead time, past data is stored in a memory and a state variable is calculated on the basis of the stored data to control a system. The film thickness controller includes an adjusting mechanism including a plurality of die lips having interference effect. In order to solve a problem due to the interference effect, the film thickness controller combines a plurality of basic control systems to control the adjusting mechanism including the plurality of die lips.

Abstract: The present invention provides an extrusion apparatus having an improved mechanism for thermally-controlled, lip gap adjustment. The apparatus includes a flow path for a gaseous cooling medium, in which flow path a plurality of temperature-responsive, lip gap adjustment members are disposed. Structurally associated with each such adjustment member is a heating wire.

Abstract: In critical surface quality plastic molded articles, especially in optical lenses and disks, an "adaptive" mold cavity is used to automatically control melt pressure and densification during mold packing to within a predetermined range of acceptable values, while normal cycle-to-cycle molding process variations produce a corresponding minor but acceptable change in the molded-part thickness. In multicavity "adaptive" moldsets, permissible cavity-to-cavity imbalance without an overfilled cavity flashing at the parting line is increased. A resilient member (mechanical steel spring or elastomer or hydraulic cylinder) is interposed between the part-forming mold insert surface and the associated clamp plate for that half of the moldset. When the mold is initially closed, a separation distance between the A and B mold insert is less than the molded product specification's minimum acceptable part thickness.

Abstract: An apparatus for manufacturing atherectomy torque tubes includes a mechanism for rotating a tube liner about its longitudinal axis at a rotational velocity. A carriage is translatably positioned along the longitudinal axis. A mechanism for winding a wire about the tube liner is mounted on the carriage. A mechanism for coating the tube liner with an epoxy material is also mounted on the carriage. In a preferred embodiment, wire is wound onto the tube liner inside a reservoir of urethane epoxy bath which is moved along the tube liner. A laser sensor measures the coated tube to provide a signal representative of the final outside diameter of the tube and a computer uses this signal to control the angular velocity of the rotating tube liner and the linear velocity of the carriage which moves the wire winding and coating mechanism along the tube.

Abstract: There is disclosed a film thickness controller which contains a large dead time and in which, in order to solve a problem due to the dead time, past data is stored in a memory and a state variable is calculated on the basis of the stored data to control a system. The film thickness controller includes an adjusting mechanism including a plurality of die lips having interference effect. In order to solve a problem due to the interference effect, the film thickness controller combines a plurality of basic control systems to control the adjusting mechanism including the plurality of die lips.

Abstract: An extrusion die slot for extruding flat thermoplastic webs has a plurality of plates mounted to the flexible lip of the die body. A regulating force from a control element is applied to the plates, and so to the flexible lip, via the flexible strip pressed between the control element and the plates.

Abstract: A lip drive structure for a T-die including a main body structure member having an elongated nozzle orifice defined by a pair of lip portion facing each other, a nozzle structure portion including one of the lip portions and formed at the lower end of the main body structure member so as to be integrally connected to the same through an elastically deformable portion, a plurality of bellows disposed on a side surface of the main body structure member on the side of the nozzle structure portion, and a drive section structure member fastened to the bellows at its upper portion and fastened to the lip structure portion at its lower portion. Air supply holes are formed in the drive section structure member to enable the bellows to be supplied with compressed air. The drive section structural member is divided into a plurality of elements in the longitudinal direction.

Abstract: This invention relates to a tubular stretching method for producing a stretched film by passing a tubular thermoplastic resin film between pairs of nip rolls having mutually different peripheral speeds and by inflating the tubular film with internal pressure under heating and a stretching apparatus to be employed therefor. The pairs of nip rolls include at least three pairs of nip rolls. Pressurized air is admitted into a stretched bubble situated between the first and second rolls through a slit-like air injecting nozzle, and the bubble formed by the supplied pressurized air is inflated and stretched under heating. In this stage, if desired, the amount of injected pressurized air is controlled by manual or automatic control by detecting the diameter of the bubble so as to keep the bubble's diameter constant. After stretching, the tubular film is collapsed and is introduced to the second nip rolls. Both side ends of the collapsed film are cut open with film cutting knives to make two sheets of flat films.

Abstract: The present invention relates to a method of and an apparatus for manufacturing biaxially oriented film. A tubular original film which has been extruded by an extruding die is biaxially oriented by heat and air injected to the inside portion thereof being conveyed to nip rolls each having an individual circumferential speed. The temperature of heat to be applied to the film is controlled on the basis of the detected film thickness for the purpose of obtaining a uniform film thickness distribution. Furthermore, the film can be made uniform by adjusting the outer diameter of the bubble-shaped oriented film by adjusting the distance between two sets of nip rolls on the basis of the measured width of the film. In addition, when the thus-oriented film is subjected to a heat treatment, temperature of heat is arranged to be a predetermined temperature as to prevent adhesion of the films.

Abstract: A T-shaped film extrusion die having a T-shaped die main body, a device for detecting the thickness of a resin film formed by extrusion to generate a detection signal, a device for generating a correction signal on the basis of a difference between the detection signal and preset thickness data, and a lip-width adjusting device for driving lip-width adjusting bolts on the basis of the correction signal to adjust the width between lips of the die so that the resin film has a preset thickness.

Abstract: An apparatus for laying a mat of fibrous material which includes an upwardly inclined belt onto which the fibrous material is fed, one or more combing roller located above the belt, a stripping roller at the upper end of the belt for removing the material from the belt and passing it into a mechanism for laying the material into a mat. The angle of inclination of the incline belt and the position of the first combing roller as such that the material can build up to reach a critical angle of repose and then slide back down. A second combing roller located upstream of the first combing roller serves to comb the material to a constant depth, and the speed of the incline belt is adjustable to determine the amount of material leaving the incline belt and thus regulate the thickness of the formed mat.

Abstract: A film blowing line is disclosed which includes a winding roll to receive a folded film; the film having initially been tubular in shape. In the invention, the diameter of the winding roll is measured in an axial direction and, correspondingly, the thickness can be controlled with the aid of an actuating member, as a rule, differentially across the circumference of the tubular film.

Abstract: A method and apparatus for manufacturing one phase of a silica crucible including controlling the filling of a hollow mold of cylindrical shape, which rotates about its vertical axis, with grains of crystallized quartz. The grains of material are continuously introduced into the mold and are deposited on or near the lateral wall face of the mold in the form of a cylindrical layer, E, of internal radius R. A beam of light is directed to form a luminous spot on the summit of the layer from the commencement of its formation and the radial displacement of the spot on the layer is observed. The height at which the grains are introduced and the height of the trajectory of the luminous beam are modified as a function of the position of the luminous spot relative to determined reference points.

Abstract: The pivoting of a guide roller (20) together with a conveyor belt (19) running around it, as well as a pressing roller (25), from a standby position (A) into a resting position (B) is optimized both for thick dough and for thin dough. The pivoting operation takes place in the case of thick dough after one turn has been wound on the dough reel (18). For thin dough, the pivoting operation takes place after about two turns of the dough are on the reel.

Abstract: A fishing line, or just a leader, has a core (11) which is coated by plastic material as it is pulled through an extruder (3) and then a quench bath (4) by a variable speed drive device (9). Very fine control can be exerted by laser devices (11, 12) before and after coating, and adjusting a selection of parameters such as drive speed, extrusion rate, pressure and temperature, and cooling. A double coating may be applied or additives mixed in the extruded plastics which will give a desired floating or sinking characteristic.

Abstract: An injector head for producing tread strips, and including a thickness-adjusting slide and two side plates for forming an essentially trapezoidal tread strip profile. The side plates are mounted so as to be adjustable in a lateral direction, and are supported against the thickness-adjusting slide in a direction parallel to the direction of extrusion. The thickness-adjusting slide extends on the shorter side of the trapezoid over the entire width of the tread strip. Either the thickness-adjusting slide or the side plates are mounted on an injector head end member that can swivel away.

Abstract: The present invention incorporates a conductor contact apparatus, a conductor defect detector, and a relay or equivalent added to the emergency stop circuit of a conductor insulation extruder apparatus in order to detect conductor defects and shut-down the extrusion apparatus before the conductor defect can cause the extruder to become blocked, interrupting normal production operations. The defect detector is especially adapted to detect variations in the cross-sectional area (or apparent cross-sectional area) of a conductor being insulated.

Abstract: Process and apparatus for spreading a chip web from a supply over a width corresponding to the web width on a substrate moving below the supply. Such spreading is accomplished according to a web height distribution specified in the web transversely to the direction of web travel. The apparatus includes a rake-like distribution device and a distribution chute arranged between the supply and the web laydown for the purpose of eliminating defects caused by delivery elements in the transverse distribution of the chip web. An arrangement of several rakes inclined toward one another functions to control the transverse chip distribution.

Abstract: The thickness distribution across a sheet material, formed by biaxially stretching a molten material web delivered from a die, is automatically controlled by a control processing wait. A correspondence relationship between adjustment of adjusting means arranged on the die and the variation of thickness distribution of the sheet material after formation thereof is sequentially estimated using a Kalman filter built into the control processing unit. Responsive to the estimated relationship, the adjusting means are controlled by optimum amounts in order to enable the thickness distribution to approach a target distribution. The accuracy of thickness control of the sheet material can be greatly increased and accurate control can automatically follow any variation in the conditiond of a sheet forming process. The correspondence relationship between the thickness distribution of the sheet material and the adjusting means on the die can be monitored and displayed.

Abstract: The process for making a thermoplastic foil involves the use of a wide-outlet or long-slit die which has at least one outlet-gap-defining adjustable die lip, an opposing gap-bounding lip and a group of piezotranslators distributed over the length of the outlet-gap-defining adjustable die lip, each of which is part of a control loop, acts as a positioning member and is associated with an individual section of an outlet-gap-defining adjustable die lip. At least one actual value of the foil thickness of the thermoplastic foil formed is measured with a measuring device and is fed to a controlling processor. Each of the piezotranslators is controlled by a controlling processor with a controlling variable.

Abstract: The invention regards a universal machine for making cakes in usual bakeries all the way from a finished dough to baking. The machine extrudes soft or thick dough, makes portions and forms cakes for arranging on baking plates and baking, and extrudes cream and jam and similar materials. The machine is also suitable for making licorice, confectionery and any kind of forming and making portions of viscous, extrudable materials. The machine includes automatic measurement of thickness and control of thickness of the dough-cake by use of a photocell, and the photocell is fitted with runners, scale of measurement and patterns of thickness, so that the thickness of each cake is measured and cut independently. The machine is fitted with automatic measurement of frequency and control of frequency of cakes, relying upon the control of thickness. The machine has many cylinders utilizing the automatic control of thickness.

Abstract: A method and an apparatus for measuring and 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 in the thermoformer oven at a sensing location in a forming station receiving the material from the over in order to regulate the thickness of the plastic material prior to its conveyance into said forming station. This is effected by varying the rate of advance and dwelling time of the material in the oven, and optionally, also concurrently regulating the temperature in the oven to optimize control over material blow-up.

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 an two screw extruder presents an even wall thickness over the circumference.

Abstract: A method for monitoring and controlling the wall thickness of an extruded profile of heated polymeric material that issues from an extrusion die. The die includes a plurality of discrete sectors each having a controllable heat source and a temperature sensor, and the temperature at each particular sector is controlled and adjusted in order to change the measured wall thickness corresponding with that particular sector as necessary to provide a desired wall thickness distribution. A characteristic curve for the particular material is provided as an input quantity and involves the relationship between a change in extrusion temperature versus the corresponding change in wall thickness, and that relationship is utilized to effect rapid adjustment of wall thickness by means of a temperature change in order to provide a finished article having the desired thickness profile and without having excessive material, to thereby reduce the weight and cost of the extruded article.

Abstract: A method and apparatus for machining dough that takes into account the different flow regimes exhibited by the dough during processing. As in conventional systems, the apparatus includes a hopper for extruding dough in a sheet and pairs of powered rollers for sizing the sheet. A computer controls the system. Mass flow rate is made constant throughout the system by establishing a master flow rate based upon predetermined criteria related to the product being produced, and the computer monitors the weight of the extruded sheet to maintain a constant input to the powered rollers. The flow rate is varied to remain constant by comparing the input to output, as measured by the sheet thickness at the cutter station. The gage rollers are controlled by setting a nominal roller speed, trimmed according to the tension present in the sheet upstream of the gage roll, as reflected in the position of a loop in the dough sheet between the gage roll and the pair of rolls immediately upstream of same.

Abstract: In preparing a film by extruding a molten thermoplastic resin, a heater in which a temperature profile varying in the width direction can be set is arranged in the width direction in the vicinity of a die lip, and a temperature sensor for detecting a resin temperature profile in the vicinity of the outlet of the die lip and a sensor capable of detecting a thickness profile of a film or the like in the width direction are disposed. The output of the heater is controlled according to signals from the temperature sensor and thickness sensor to automatically adjust the thickness of the film or the like in the width direction, whereby a homogeneous film with a reduced thickness unevenness can be stably prepared with a high precession of control of the thickness unevenness. .

Abstract: A slit nozzle for an extruder has a nozzle orifice defined by two side surface portions of the nozzle body, at least one of the side surface portions being in the form of a flexible lip portion connected to an adjusting arrangement for varying the width of the nozzle orifice. The adjusting arrangement includes at least one lever arm connected at one end to the lip portion and at its other end to a mechanical adjusting means including a screw operable to control deflection movement of the lever arm in a plane which extends transversely with respect to the side surface portions.