Abstract: Particleboard made from particles in the form of chips or fibers or the like is made by distributing a mass of chip material onto an endless belt conveyer system. The mass of material is subsequently passed to a precompressor, a high frequency preheating device, a further press and a finishing press. The unheated further press serves to reduce the thickness of the material to substantially that of the finished board prior to its consolidation by temperature and pressure in the finishing press. A further endless belt contacts the surface of the material and runs through the precompressor, the high frequency heating device and the further press and serves to counteract any tendency of the chip material to expand after leaving the precompressor. This endless belt additionally yields a number of other significant advantages, in particular a reduction of loss of heat from the material prior to reaching the finishing press.

Abstract: A high frequency industrial generator, especially suitable for supplying power to a device for heating an electric poorly conducting substance such as a fleece of a cellulose material, comprises two hollow concentrically disposed conductors each of square section and supporting respective electrode plates of an associated capacitor. All the plates are vertically disposed and lie at right angles to the walls of the respective conductors. In the middle of the electric plates there is situated a triode electron tube electrically connected to the plates to form an oscillating circuit. The anode potential and cooling water supply for the electron tube is located within a field free space inside the internal conductor. One set of electrode plates can be adjusted relative to the other to adjust the frequency and the arrangement ensures only low electrical losses are incurred.

Abstract: A bottom-belt bunker which receives and delivers particles for the manufacture of fiberboards, chipboards, or the like, and containing cellulose, is disposed upstream of a glue applicator or a front of a forming station. A centrally located feed opening is associated with a drivable auger disposed transverse to the longitudinal extension of the bunker. The auger has a pair of opposed helical blades or flights. A shoveling slide having an adjustable stroke is disposed beneath the auger and partially encompasses the same, the length of the slide being smaller than half the width of the bunker and/or half the length of the auger. Terminal positions of the reciprocating slide are disposed at a spacing from the side of the bunker and the average moving speed of the slide is approximately half that of the velocity of the helical blades of the auger.

Abstract: A gluing machine for gluing lignocellulose-containing particles such as fibers, shavings, dust, and the like, for the production of pressed wood plates, in which a housing has, at one end, an intake for material to be glued. At the other end of the housing there is an outlet for glued material. A stirring mechanism having mixing tools rotating with a shaft, is centered in the housing. Glue supply nozzles are also provided. The mixing tools are in the form of rods which run parallel to the stirring mechanism shaft, and they are supported on their ends on this shaft. The rods carry spaced cross surfaces, and are relatively close to the housing interior wall. At least some of the cross surfaces are inclined relative to the longitudinal axes of the rod with either the stirring mechanism shaft inclined from the horizontal in the direction towards the outlet downward, or with the horizontal stirring mechanism shaft.

Abstract: Apparatus for the production of a middle layer of chipboards or the like and/or for the manufacture of chipboards formed only from middle layer material includes at least one spreading station associated with a spreading chamber arranged above a moving support for the reception of a chip layer or the like, the entire fine or coarse materials serving for the formation of a type of middle layer being fed by at least one metering tank to the support. The apparatus is further characterized in that at least one inclined screen which can be reciprocated in an essentially horizontal direction is disposed underneath the delivery point of the metering tank and a spreading roll is disposed underneath the lower edge of the screen in parallel to the screen edge, the roll serving for feeding the coarser material to the space lying beneath the screen.

Abstract: A continuously operable rough or finishing press for the manufacture of panels such as, for example, chipboards, fiberboards and the like, which press includes two endless plate bands or belts arranged one above the other to define a material treatment path therebetween. The endless plate bands include a number of plate elements pivotally connected to each other with each plate element being provided at edges thereof with spaced recesses and projections. At least one groove is provided in a middle or center area of each of the plate elements and/or at least one groove is provided at the projections of each of the plate elements so as to minimize deformation of the plate elements and/or arching of the center portion thereof during an operation of the press.

Abstract: An apparatus for metering particles containing lignocellulose employs a measuring and control unit. This unit compensates volumetric fluctuations in the bulk density of particles in a metering tank moving at constant speed, through the use of radioactive detection.

Abstract: 1-Nitroanthraquinone is produced in highly pure form by a process comprising the steps of partially oxidizing 3-nitro-o-xylene (I) to 2-methyl-3-nitrobenzoic acid (II) converting II to 2-methyl-3-nitrobenzoyl halide (III), converting III to the novel intermediate 2-methyl-3-nitrobenzophenone (IV), oxidizing IV to 2-benzoyl-6-nitrobenzoic acid (V) and cyclizing V to 1-nitroanthraquinone.

Abstract: A process for the production of shaped articles from wood particles, especially chipboards, wherein the basic cellulosic material comprised of wooden articles is admixed with at least one mineralizing agent, water, and a hydraulic binder such as cement, the mixture is shaped and then pressed at a constant temperature above the freezing point; the process being characterized in that the water required for activating the hydraulic binder is added and admixed with the basic cellulosic material before the addition of the mineralizing agent and the hydraulic binder.

Abstract: The temperature distribution through the thickness of a layer of particulate matter formed by air screening and by compressing in a press for forming a particle board therefrom is made more nearly uniform by heating the air stream or air streams used for the air screening of the particulate matter.

Abstract: A guide arrangement for endless belts of a continuously operating press which belts are guided by a plurality of rolls arranged on a semi-circular track disposed at the inlet and/or outlet zone of the press and at the upper and/or lower press sections. The respective ends of each of the rolls are pivotally arranged in bearings with each of the bearings being associated with a disk-shaped member fashioned as a half ring. One or both of the disk-shaped members are movable in a controlled manner along a semi-circular track whereby the steel belt is secured against lateral movement.

Abstract: Process and apparatus for the production of chipboards, fiberboards, or like panels from a mixed material, the components of which have specific gravities that differ relatively greatly from one another. In one preferred embodiment, the components are fed separately from one another to the bottom belt of a mixing bin to form a plurality of thin layers. The mixing bin is arranged upstream of a fine-metering device, which in turn, meters the mixed material for feeding into a press. Another preferred embodiment feeds the mixture components to the bottom belt mixing bin together, while depositing the mixture material in obliquely oriented layers in superimposed strata so that the angle of each layer is smaller with respect to the horizontal than the natural angle of repose of the individual mixer components.

Abstract: A device for forming chip boards and the like including a conveyor belt for conveying a fleece of chip material to a press for compressing the fleece, a motor for intermittently moving the conveyor belt by one press length and at least one spray nozzle for spraying a fluid mist onto the fleece before entering the press is further provided with a moving coil regulating device for controlling the supply quantity of fluid supplied to the spraying nozzles. The moving coil regulating device is made responsive to the rotational rate of the motor driving the conveyor belt so that the rate at which fluid is supplied to the fleece varies in accordance with the movement of the conveyor belt.

Abstract: Process and apparatus for the continuous production of chipboards, fibreboards, or the like from lignocellulose containing particles mixed with binders, which particles are strewed onto an endless conveyor belt forming a mat or fleece, which mat is subsequently introduced into a press and compressed therein to a panel sheet under the effect of heat during which period the binder hardens, characterized by heating apparatus for heating the upper cover layer of the mat before the mat enters the feeding zone of the press. Preferred apparatus for heating the upper cover layer of the mat includes indirect radiant heat supplying devices such as infra-red lamps. The preferred temperature range to which the upper mat cover layer is heated is 30.degree. to 50.degree. C.

Abstract: A wide belt grinding machine which is provided with a control member to reverse, in the case of power failure, the pressure force effective on a piston which relieves the tension on an endless abrasive belt via a tensioning roll.

Abstract: A continuously operable press utilizing facing endless linked together platen belts for compressing chip materials into chipboards, fiberboards, and the like. A plurality of pressure rollers are provided along the belts for pressing the same towards one another along the portion of their travel paths where they are in facing relationship. With the belts travelling horizontally at the position of their facing runs, these pressure rollers are biased by piston-cylinder apparatus or the like in a vertical direction. For accommodating adjustment of the position of the pressure rollers in the horizontal direction, without necessitating stoppage of the press, needle bearings are provided between supports for the bearings of the pressure rollers and the fixed press frame. Adjusting means in the form of piston-cylinder apparatus are provided for effecting the horizontal adjustment of the bearing supports for the pressure rollers.

Abstract: An apparatus for forming a layer from a mixture of particles having variable particle sizes and including throwing rolls for casting the particulate mixture onto a flat support is further provided with a blower arranged to reverse the direction of horizontal movement of the particles as they fall onto the support by means of air flow.

Abstract: A continuously operating press for the production of panels, such as chipboards, fiberboards, and the like, and including two cooperating endless plate belts arranged so that the material forming the panels can be conveyed by and be compressed between the belts is also provided with drivable pressure rollers for driving the endless plate belts which are adapted to be moved to an oblique angle with respect to the path of travel of the belts. By moving the drive rollers to an oblique position, lateral displacement of the flexible endless belts surrounding the endless plate belts can be prevented.

Abstract: A continuously operating press utilizing facing endless belts for compressing chip material into chipboards, fibreboards and the like. Each of the belts is constructed as an endless belt formed of a plurality of heatable planar chain links. For conveying and directly engaging the chip material, corresponding endless steel bands envelope the chain belts. Gas flame burners are arranged in casings for directly heating a portion of the chain run at a position spaced from the engagement with the chip material. Each of the casings also include burner exhaust gas conducting channels for conducting the hot exhaust gases adjacent portions of the chain which are not impinged upon by the flame at a particular given time. Also, conduit means for the flame burner exhaust gases are provided for conducting the exhaust gases to heat the endless steel bands by way of Z-shaped channeled housings arranged at a position spaced from the casings for the flame burners and immediately adjacent the steel bands.

Abstract: Apparatus for the continuous production of chipboard, fibreboard or like panels, comprising a tensioned endless steel belt guided over a plurality of rollers and partially around a heated revolvable press drum such that said rollers press the belt against said drum, sprinkler apparatus disposed over a portion of the belt which extends horizontally before said drum in the direction of movement of the belt such that material to form said panels sprinkled onto said portion of the belt is pressed between the belt and the drum to form a web of material, wherein at least one of said plurality of rollers has over its width a convexly ground surface, whereby panels produced on the apparatus can have substantially uniform thickness and weight.