Abstract: In a method and conveyor for conveying a solid material by means of parallel, oblong transfer elements that move back and forth in the direction of transfer, most of the surface of the transfer elements moves in the direction of transfer at the same time and at least part of the surface thereof is inclined towards the center of the conveyor. Pieces of material lying on inclined outermost transfer elements are carried on a lower longitudinal part of the transfer elements, the angle of inclination of the part about the longitudinal axis being smaller than the angle of inclination of the upper part thereof. Thus, the support force exerted by the transfer elements on the pieces lying thereon, and the friction force between them and the pieces lying thereon, increase.

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: The present invention relates to a method controlling a drum debarker by way of using the drum weighing information in the control of the drum debarking process. The method comprises the steps of determining the weight of the contents in the drum determining the filling degree of the debarking drum determining the average density of the log bunch tumbling in the debarking drum from drum weighing information and drum filling degree information, and determining a target value for the log retention time or debarking work in the debarking drum. Based on the information thus obtained, at least one following variables is controlled: the drum rotating speed, discharge rate of logs from the drum and infeed rate of logs into the drum so as to achieve the desired target value for the log retention time or debarking work in the debarking drum.

Abstract: The present invention concerns a method and an apparatus for defrosting frozen wood prior to debarking. The defrosting method of logs of the invention is based on bringing heat zone-specifically to logs in transfer motion on a conveyor according to their heat receiving capacity immediately from the moment of starting of the defrosting, and at the end of the defrosting process, the heat volume per time unit, supplied at a higher temperature, is only a part of the heat volume of the starting phase of the defrosting process. For instance, it is possible to spray water on the wood to be defrosted so that the row interval of the showers in the initial part of the piping is a fraction of the row Interval in the tail end of the piping. In the tall end of the defrosting conveyor steam can also be supplied.

Abstract: The present invention concerns a method and an apparatus for defrosting frozen wood prior to debarking. The defrosting method of logs of the invention is based on bringing heat zone-specifically to logs in transfer motion on a conveyor according to their heat receiving capacity immediately from the moment of starting of the defrosting, and at the end of the defrosting process, the heat volume per time unit, supplied at a higher temperature, is only a part of the heat volume of the starting phase of the defrosting process. For instance, it is possible to spray water on the wood to be defrosted so that the row interval of the showers in the initial part of the piping is a fraction of the row interval in the tail end of the piping. In the tail end of the defrosting conveyor steam can also be supplied.

Abstract: A wood chipping method and a disc chipper provided with knives (4). The chips (11), after having separated from a log (3), pass through a chip opening (12) in the disc (1) and hit an impact surface (10) located after a knife. Along different portions of the knife (4), a stronger impact effect is caused in proximity to the centre than in proximity to the outer periphery of the disc. The direction of the impact surface (10) deviates more from the direction of the rear surface (15) of the knife in proximity to the centre of the disc than in proximity to the outer periphery of the disc. The distance of the connecting line between the rear surface (15) of the knife and the impact surface (10) from the cutting edge (16) of the knife can be longer on the outer periphery of the disc than in the centre of the disc.

Abstract: The present invention relates to a method controlling a drum debarker by way of using the drum weighing information in the control of the drum debarking process.

Abstract: Methods are disclosed for removing the bark from logs including transporting the logs in a longitudinal direction, cutting the surface of the logs as they move in the longitudinal direction using blades projecting upwardly with respect to a bottom surface on which the logs are supported and which is moving transversely under the logs, and simultaneously causing the logs to move so that the logs alternately contact the blades and are displaced from contact with the blades. Apparatus for removing the bark from logs is also disclosed.

Abstract: The invention concerns a knife disc arrangement of a disc chipper, said arrangement comprising a rotating knife disc (1), knives (3), wear plates (4) and supporting strips (11) supporting the wear plates. The invention also concerns a hinge strip acting as a supporting strip (11) for the wear plate. The knives are supported against the direction of rotation of the disc by fitting the base edge (9) of the knife against a supporting surface (10). The supporting surface (10) supporting the base edge of the knife (3) is located in the supporting strip (11).

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 screw conveyor is provided with a drive in which cogged wheels are supported such that they are radially movable in relation to each other, parallel to a straight line perpendicular to a pressure line of tooth contact of the cogged wheels and parallel to surfaces of contact. The screw conveyor includes a frame adapted to turn around a vertical turning axis and a conveyor screw adapted to turn with the frame. A second one of the cogged wheels is supported such that it is movable vertically.

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 mounting a wear plate and a knife base on a disc chipper's disc, and a disc chipper. The wear plate (6) rests against the knife base (4) via two counter surfaces (12), one of which forms in the wear plate (6) a groove in parallel to the knife (3) and the other forms in the knife base (4) a ridge which can be fitted into this groove. The tightening force of the fastening bolts (17, 18) of the wear plate (6) presses the knife base (4) against the disc (1) by means of the wear plate via these counter surfaces (12).

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: The invention relates to a knife system for a machine used in wood chipping, a knife (10), a guide component (14) and a filler part (24) and method of exchanging knives. The system comprises at least one turnable or at least two exchangeable guide components (14), where at least two guiding surfaces are mutually at different distances from the guide component surface supported on the disc.

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: 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 means of conveyance for solid material, f.ex. tree trunks (6) or bark, whereby the solid material is conveyed with parallel, oblong transfer elements (4) moving back and forth in transfer direction. A larger part of the surface of the transfer elements (4) is moving forward at a time than moving backward. The speed of the return motion of the transfer elements is higher than that of the feed motion of the transfer elements. Transfer elements (4) at sides of the conveyor have been inclined on their longitudinal axis so that they slope towards the center of the conveyor. In this way the friction force between the particles (6) of the material to be conveyed is increased and the friction force between the material (6) to be conveyed and the transfer elements (4) is decreased.