Abstract: The present invention concerns a chipping or crushing apparatus having a prominent speed of rotation and mass inertial moment. The main parts of the apparatus include a chipping disc or a rotor, a short circuit motor and a frequency converter connected to the circuit of the motor. From the chipping disc, respectively from the rotor or from the motor there is arranged a data connection of the speed of rotation to the frequency converter, and the frequency converter has been arranged to control the frequency of the motor current by means of said data so, that in a situation of peak load, when the motor load (torque M) has reached the nominal load, the frequency converter keeps the motor load at the nominal load by decreasing the frequency of the motor current. Thereby kinetic energy of the rotating components will be released for use in the peak loads corresponding to the decrease of the speed of rotation.

Abstract: The present invention concerns a method for transferring tree trunks or other loose material in a troughed conveyor by exerting to the material to be transferred abrasive forces acting sequentially in transfer direction and in return direction. The abrasive forces acting in the transfer direction are exerted to the material to be transferred simultaneously on both of the partial surfaces between the stationary centre portion and the stationary side surfaces. The abrasive forces acting in the return direction are exerted non-simultaneously as well with respect to the abrasive forces in the transfer direction as with each other. The invention further concerns a respective apparatus.

Abstract: The present invention concerns a chipping or crushing apparatus having a prominent speed of rotation and mass inertial moment. The main parts of the apparatus comprise a chipping disc or a rotor, a short circuit motor and a frequency converter connected to the circuit of the motor. From the chipping disc, respectively from the rotor or from the motor there is arranged a data connection of the speed of rotation to the frequency converter, and the frequency converter has been arranged to control the frequency of the motor current by means of said data so, that in a situation of peak load, when the motor load (torque M) has reached the nominal load, the frequency converter keeps the motor load at the nominal load by decreasing the frequency of the motor current. Thereby kinetic energy of the rotating components will be released for use in the peak loads corresponding to the decrease of the speed of rotation.

Abstract: The invention relates to a continuously operating drum debarking method for processing logs. The logs to be de-barked into a debarking drum (4′) having no bark discharge openings in the shell. The logs together with the bark loosened therefrom are discharged to a downstream bark separating system. Therein, the logs are subjected mutual movements resulting in the removal of bark from about the logs. The thus separated bark pieces are further discharged onto a conveyor system located under the separating equipment.

Abstract: The present invention relates to method for separating loose bark from a flow of debarked wood logs are conveyed substantially in the direction of their longitudinal axis along a substantially horizontal conveyor track. During their travel, the logs are forced into unidirectional accelerating rotation that simultaneously moves the logs laterally. An accelerating rotary motion is advantageously imparted to the logs on a rolling ramp adapted between two conveyors operating at different height levels.

Abstract: The invention relates to a method for improving wear resistance and thoughness about the chip exit opening of the knife base (2′,14′,15) of a disc chipper knife (1′). According to the invenetion, the surface of the knife base bordering the chip exit opening is surface hardened over an edge area (18,18′,18″).

Abstract: The present invention relates to a method for setting the conditions in the feed chute of a disc chipper according to the size of wood to be chipped. The position of the chipping anvil at the outlet end of the chute is changed in a plane which is essentially parallel to the plane of the knife disc in regard to a diagonal of the knife disc parallel to the plane of the anvil so that the inclination of the chipping plane of the anvil towards the blade disk remains substantially unchanged. Furthermore, the position of the feed chute bottom in the chipper may be adjusted to comply with the changed position of the chipping plane, where necessary.

Abstract: A method of increasing the durability of the cutting point (8) of a blade, and a blade. A compression stress (P.sub.10) is formed in at least one surface (10 or 6) joining the point (8) of the blade (1) by cold working the blade.

Abstract: A method and a feeding chute for feeding logs (10) into a disc chipper by means of the gravity. The logs (10) are supported laterally by means of adjacent bottom portions (31, 32) of the chute (3) and shoulders between those. The logs are turned parallel with the longitudinal direction of the chute by means of a moment (M) which occurs when the direction of the main axis (27) of the ellipse forming the shearing surface of the log deviates from the direction (27') perpendicular to a the direct line (30) drawn via the rotating center (28) of the blade disc and the center (29) of the ellipse. The bottom portions (31, 32) of the chute are inclined around a longitudinal axis in such a way that from two adjacent bottom portions of the chute, the one (31) further away from the rotating axis of the disc forms a bigger angle (.beta.') with respect to the horizontal plane than the angle (.beta.") formed by the portion (32) closer to the rotating axis.

Abstract: A method for improving the endurance of a blade base (6) of the disc (1) of a disc chipper, a blade base and a disc chipper. A wearing plate (10) is attached to the surface (18) of the blade base facing towards the chip opening (7), the wearing surface (10) of which is shot peened.

Abstract: A drive system of a rotating drum (1), where the drum is supported with a flexible support system. The drive system consists of a gear rim (2) and a pinion gear (4) in contact with the gear rim. The driving pinion gear is supported on a moving platform (10). The drum (1) is provided with a guiding rim (5) and a guiding wheel (6) rolling against it and supported on the same platform as the driving pinion gear. The sum of the outer diameters (D.sub.2 and D.sub.1) of the guiding rim (5) and the guiding wheel (6) is equal to the sum of the pitch diameters of the gear rim (2) and the driving pinion gear (4). The guiding wheel (6) can be pressed against the guiding rim (5) to maintain the right clearing between the teeth of the pinion gear (4) and the gear rim (2) when the center of the drum (1) is moving.

Abstract: A method and press for pressing material by way of feeding the material into a gap formed between two pressing surfaces, in which gap the cross section of the material flow is tapered in the forward transfer direction of the material. The material is pressed between pressing surfaces formed by parallel, beam-shaped transfer elements which are reciprocatingly moved in the direction of material flow in two alternating groups so that the mutually opposed transfer elements of both pressing surfaces are moved in a mutually synchronized manner in the same direction. During the forward transfer motion the pressing force exerted by the transfer elements on the material is greater than the pressing force exerted during the return motion of the transfer elements.

Abstract: The present invention concerns a screening method and apparatus for sorting wood chips into three categories, namely, accept chips, overthick and/or overlong chips requiring further processing and reject fines. The chips are fed onto a disc screen. A major portion of fines and a portion of accepts fall by gravity through clearances between the discs (1) of the disc screen and a portion of the chips travels over the disc screen. Screening of chips on the disc screen is cut short before all accept chips have fallen through the disc screen. Chips travelling over the discharge end of the disc screen are routed onto a roller screen (10), whereby the remaining portion of accepts can fall by gravity through the roller screen while overthick and/or overlong chunky chips are conveyed over the discharge end of the roller screen.

Abstract: A method and apparatus for removing liquid from particles of compressible material includes feeding particles to two opposing press surfaces that are separated by a distance that decreases along a feeding direction wherein at least one of the press surfaces is formed of a number of parallel transfer elements and wherein each transfer element is connected to a corresponding pressing actuator. The sum of a surface area of each transfer element forms a total press surface area for one of the press surfaces. The transfer elements are reciprocated in a forward and backward motion along the conveying direction such that a total press surface area includes at any particular time a forward moving surface area that is larger than any backward moving surface area.

Abstract: Method and chipping device for cutting chips (10) from elongated pieces of wood (5) in a manner that the wood to be chipped is fed into a rotating cylinder (1) and chips are cut of the side of the piece of wood by ranges of blades formed by several blades (7) inside the cylinder surface. The wood to be chipped (5) is directed to the cylinder in a manner that the angle between the pieces of wood (5) and the ranges of blades is acute. Each piece of wood to be chipped is in contact with two or more blades (7) in different range of blades during the cutting.