Abstract: A method and apparatus for converting a flitch into sheets of veneer. The method and apparatus include providing a drive mechanism which causes relative motion of a knife in contact with the flitch. The relative motion is relatively slower during one part of the cutting stroke and is relatively faster during another part of the cutting stroke.

Abstract: The invention concerns a method for peeling veneer from a log (2). Veneer (4) is peeled tangentially from the circumferential surface of a log rotated around its longitudinal axis under conditions determined by the distance (knife gap) between the knife (3) and the nose bar pressing the surface of the log immediately in front of the cutting point. The peeling knife as well as the nose bar is moved towards the rotation axis of the log corresponding the proceeding of the peeling. At the ending stage of the peeling, the distance between the peeling knife and the nose bar is reduced substantially in accordance with the thickness of the veneer being peeled.

Abstract: A method of cutting a wood block for production of veneer by a rotary veneer lathe. The veneer lathe includes a veneer knife, a number of rotatable peripheral drive wheels placed parallel to the veneer knife and each having a number of tooth-like projections pierceable into a wood block for driving the wood block for rotation about its axis, and a guide member for guiding veneer peeled from the wood block. The cutting of the wood block is done at a first position of the peripheral drive wheels where the veneer peeled from the wood block is pierced by the projections to such an extent that substantial splits are formed in the veneer along wood grain thereof, and also at a second position where the projections provide no force to the veneer moving past the guide member that causes the substantial splits in the veneer.

Abstract: A method of cutting a wood block for production of veneer by a rotary veneer lathe. The veneer lathe includes a veneer knife, a number of rotatable peripheral drive wheels placed parallel to the veneer knife and each having a number of tooth-like projections pierceable into a wood block for driving the wood block for rotation about its axis, and a guide member for guiding veneer peeled from the wood block. The cutting of the wood block is done at a first position of the peripheral drive wheels where the veneer peeled from the wood block is pierced by the projections to such an extent that substantial splits are formed in the veneer along wood grain thereof, and also at a second position where the projections provide no force to the veneer moving past the guide member that causes the substantial splits in the veneer.

Abstract: The invention relates to a knife assembly for a veneer lathe, the knife assembly comprising heads having mounted therebetween a knife beam and a nose bar beam, the beams respectively supporting a peeling knife and a solid nose bar. The knife assembly is turnable about an axis of rotation aligned parallel to the longitudinal axis of the peeling knife and the nose bar, whereby the angular position of the knife assembly relative to the lathe carriage heads is adapted to change about this axis of rotation in compliance with the progress of veneer peeling. In the knife assembly, the angular position of the nose bar relative to the peeling knife is adapted changeable during peeling in order to control the angle between the nose bar and the peeling knife.

Abstract: A station (10) for shearing wood sheets from a log comprises a shearing blade (18) and a pair of chucks (16) supporting log gripping means (21). The chucks are powered to rotate around an axis (20) parallel to the blade and the gripping means (21) are movable to change the inclination of the gripped log with respect to said chuck rotation axis.

Abstract: The invention relates to a knife assembly for a veneer lathe, the knife assembly comprising heads having mounted therebetween a knife beam and a nose bar beam, the beams respectively supporting a peeling knife and a solid nose bar. The knife assembly is turnable about an axis of rotation aligned parallel to the longitudinal axis of the peeling knife and the nose bar, whereby the angular position of the knife assembly relative to the lathe carriage heads is adapted to change about this axis of rotation in compliance with the progress of veneer peeling. In the knife assembly, the angular position of the nose bar relative to the peeling knife is adapted changeable during peeling in order to control the angle between the nose bar and the peeling knife.

Abstract: A station (10) for shearing wood sheets from a log comprises a shearing blade (18) and a pair of chucks (16) supporting log gripping means (21). The chucks are powered to rotate around an axis (20) parallel to the blade and the gripping means (21) are movable to change the inclination of the gripped log with respect to said chuck rotation axis.

Abstract: A veneer lathe knife assembly includes a lower portion supporting a veneer cutting knife, and a upper portion supporting a backing nose bar. The upper portion includes adjustment screws, for example, for adjusting a position of the nose bar in the upper portion of the assembly. To perform a fine adjustment of the knife gap formed between the cutting knife and the nose bar, the adjustment screws are individually temperature controlled to compensate for a thermal expansion of the adjustment screws, thus maintaining the knife gap along the length of the knife assembly.

Abstract: Disclosed herein is a new kind of veneer which has the cross grain (such as wavy grain and interlocked grain) artificially formed on the surface of straight-grained veneer cut by quarter sawing from a species of wood which should yield the cross grain but actually has no cross grain. Disclosed also herein is a method of producing the cross-grained veneer, said method comprising cutting wood into veneer of desired thickness which assumes the straight grain, by using a veneer peeling machine equipped with a knife whose cutting edge waves continuously in the lengthwise direction, and flattening the veneer having an uneven surface by means of thermal fixing or hot pressing, thereby artificially forming the cross grain on the surface of the straight-grained veneer. The knife is constructed such that the cutting edge waves in the widthwise direction of the knife and the troughs of the wave are disposed along the straight line extending in the lengthwise direction of the knife.

Abstract: A veneer lathe comprising a knife (2) for peeling a log (1), which is secured rotatably to a knife stock, and a roller bar (3) disposed to press a circumferential surface of the log (1) at an upstream side, in relative to said knife (2), of a rotational direction of the log (1). The roller bar (3) has a diameter of not more than 30 mm, and is provided on the circumferential surface thereof with a large number of projections (5) whose height is not higher than the circumferential surface of the roller bar (3). The roller bar (3) is sustained in a sliding bearing (9) and adapted to receive a rotational force from a driving source. The roller bar (3) functions not only as a pressure bar but also as a power transmitting media to rotate the log (1), thereby preventing the generation of lathe check of veneer to be produced.

Abstract: An improved apparatus and method for use in the rotary cutting of wood veneer is disclosed. The improved apparatus and method are preferably employed in connection with a conventional lathe having a pressure bar. Such a lathe is of the type that is used to produce wood veneer from a workpiece of wood, such as a log. The improvement is characterized as maintaining a preselected pressure of the pressure bar against the wood, and subsequently adjusting the preselected pressure bar position by using means for doing so, thereby producing wood veneer of uniform thickness and surface quality, independent of variations in wood density and wood hardness, such variations resulting from natural growth conditions and temperature of the wood.

Abstract: A rotating log saw clamp having a clamp infeed section and a clamp outfeed section located adjacent a log saw blade. The clamp infeed section and clamp outfeed section are coupled for rotation together with the log during sawing of at least a portion of the log by the log saw blade.

Abstract: A cutting blade holding device is disclosed which is capable of preventing damage to a blade stock per se to improve operational efficiency of a veneer lathe per se and to reduce a maintenance cost. The cutting blade holding device in a veneer lathe which is supported by a frame F of the veneer lathe with its cutting blade 19 kept in parallel with a log W to be peeled and which comprises: a blade stock 5 having its side facing the log W formed with a blade retaining portion 7 for retaining the cutting blade, the cutting blade 19 being detachably mounted in the blade retaining portion 7 of the blade stock 5, and an abutment member 25 as a member separate from the blade stock 5, which is separately replaceably disposed in the upper end portion of the blade retaining portion 7 in the vicinity of a cutting edge of the cutting blade 19 mounted in the blade retaining portion 7.

Abstract: A method of controlling the clearance angle of a veneer lathe knife in a veneer lathe having a knife holder beam rotatably mounted on a knife carrier. The beam's vibration frequency is continuously measured and compared with a stored representation of a vibration frequency range (about 50-200 Hz.) characteristic of disruption of the veneer peeling operation. If the comparison reveals that the measured vibration frequency is within the characteristic disruptive range, the beam is rotatably adjusted until the comparison reveals that the measured vibration frequency no longer lies within the disruptive range. Usually, the adjustment accelerates lowering of the beam in order to make the knife clearance angle less positive.

Abstract: A veneer lathe apparatus and method are described in which the height of the nose bar roller relative to the knife is automatically adjusted during peeling by a computer control system. In addition, the two veneer exit gaps between the nose bar and the knife and between the nose bar and the knife backing member are automatically maintained substantially the same as or slightly greater than the veneer path width which is equal to the thickness of the veneer plus a clearance space of a predetermined amount. As a result the automatic control positions the nose bar as close as possible to the knife during peeling thereby greatly improving the quality of the veneer. The height of the nose bar is adjusted by moving a moveable wedge along a fixed wedge with a control cylinder in response to a computer generated control signal.

Abstract: In a veneer lathe having a knife mounted to a knife support frame with a backing plate, a roundup control system for a veneer lathe is disclosed that recognizes or detects the production of usable veneer using the body of the knife as a signal source. During initial production of veneer, the lathe produces a trash or roundup veneer that is directed to a chipper through a trashgate. When there begins production of usable veneer, the trashgate is closed and the usable veneer is directed toward production trays or stackers. A sensor or displacement detection device is mounted in the backing plate of the knife support frame lateral the unsupported portion of the knife. As the knife contacts wood, the unsupported span of the knife flexes causing the magnet to move which the sensor detects. The sensor outputs a voltage signal proportional to movement of the knife in magnitude and direction. This voltage signal is relayed to a central processing unit where it is converted into a digital signal.

Abstract: A process for selectively abrading one surface of a veneer knife at a higher rate that the other face and includes a novel way of providing lubricating and cooling fluid to the faces of the knife wherein the majority of the lubricant is provided to the face which abrades slower to further enhance the self sharpening of the knife.

Abstract: A veneer lathe including a knife blade which is adjustable to different pitch angles. The veneer lathe includes a feed carriage mounted for movement on guides fixed to a lathe frame and a blade carriage supporting the knife blade. The blade carriage is a massive member pivotally mounted by trunnions on the feed carriage so as to rotate under the force of gravity. A support device is operative between the feed carriage and the blade carriage for supporting the blade carriage against the force of gravity in an angularly biased position relative to the feed carriage. The lathe also includes a control responsive to different types of wood for allowing the means for supporting the blade carriage to retract at different rates under the force of gravity exerted on the blade carriage.

Abstract: A rotary veneer-cutting machine for cutting sheets of veneer from tree trunks comprises a bladeholder unit (19) moving on a pair of support elements (21, 23) along guides (23) for drawing a blade (16) toward the axis of the trunk (14). Said support elements (21, 23) in addition to moving along guides (23) also move independently in a direction virtually perpendicular to the guides (23) to incline and displace the blade (16) in relation to the diametrical plane of the trunk (14). Support element (21) is located virtually in a plane perpendicular to the guides (23) that passes through the edge of the blade (16) and the other support (22) in a position which is remote from said plane.

Abstract: A system for clipping veneer, peeled with curved side edges one longer than the other, into discrete full and partial panels each defined by a longer and shorter curved side edge and a leading and trailing edge, wherein the angle of the clipping knife to the direction of travel of the veneer is adjusted during passage of the peeled veneer to clip the veneer into full panels having their leading and trailing edges substantially parallel and partial panels each having its trailing edge at an acute angle to its leading edge and flowing from its shorter curve side to its longer curve side to tend to equalize the accumulated lengths of the curved side edges of the peeled veneer.

Abstract: A method and apparatus for peeling a tapered block by setting the cutting edge of the peeling knife on an angle comensurate with the taper of the block. In one embodiment, the angle remains substantially constant throughout the peeling operation so that the resulting core is tapered. In another embodiment, the angle continuously changes and the veneer is cut thicker at one side than at the other whereby to produce a tapered veneer and result in a substantially right cylindrical core when the peeling operation is completed.

Abstract: A veneer lathe apparatus is described with a powered nose bar roll of large diameter that is capable of peeling logs down to an extremely small core diameter on the order of about 21/2 inches for soft wood. The large diameter nose bar roll prevents jam-up of wood chips and trash at the junction between such roll and the log and greatly increases cutting time between lathe knife sharpenings. Both ends of the nose bar roll are connected through flexible couplings of plastic to the output shafts of two separate drive motors. The nose bar roll may be provided with a grooved outer surface for greater friction and can apply up to 40 percent of the total torque required for rotation of the log and to pressure the log for compression of its surface in front of the lathe knife during peeling. The nose bar roll is of larger diameter than the minimum log core and preferably such diameter is at least fifteen times the thickness of the wood veneer being peeled.

Abstract: A lathe for cutting a spiral strip of veneer from the surface of a log includes motor-driven mechanisms for adjusting the knife blade pitch angle and edge height, and for moving a pressure head relative to the knife to adjust the vertical gap and horizontal gap between the knife edge and the roller bar, and provides sensors for determining the actual positions of movable elements of the lathe, thus enabling computer-controlled adjustment of the movable elements of the lathe during lathe operation. A knife clamp of the lathe includes a plurality of separate clamp segments for pressing against different portions of a knife bar to hold it firmly, resisting deformation and rocking of the knife bar. Fluid-pressure-biased bearings eliminate looseness between relatively movable parts of the lathe, reducing the amount of variation of thickness in veneer produced using the lathe. Veneer thickness is controlled by monitoring cumulative movement of the lathe spindles and the main feed carriage.

Abstract: A lathe for cutting a spiral strip of veneer from the surface of a log includes motor-driven mechanisms for adjusting the knife blade pitch angle and edge height, and for moving a pressure head relative to the knife to adjust the vertical gap and horizontal gap between the knife edge and the roller bar, and provides sensors for determining the actual positions of movable elements of the lathe, thus enabling computer-controlled adjustment of the movable elements of the lathe during lathe operation. A knife clamp of the lathe includes a plurality of separate clamp segments for pressing against different portions of a knife bar to hold it firmly, resisting deformation and rocking of the knife bar. Fluid-pressure-biased bearings eliminate looseness between relatively movable parts of the lathe, reducing the amount of variation of thickness in veneer produced using the lathe. Veneer thickness is controlled by monitoring cumulative movement of the lathe spindles and the main feed carriage.

Abstract: A veneer lathe provided with a cord embedding knife. The cord embedding knife has an edge perpendicular to the veneer cutting knife of the veneer lathe. The cord embedding knife cuts into a log and forms an elongated cut therein to place a length of cord therein. At the same time, the lathe is provided with means for restraining the said length of cord firmly in the elongated cut until it releases the cord downstream of the edge of the veneer cutting knife. This structure ensures that the elongated cut is formed without causing a buckling of the veneer sheet or the like while the cord embedded in the elongated cut in the veneer sheet cut off from the log is firmly retained in the cut and prevented from slipping out of the cut.

Abstract: A veneer reinforcing unit is provided. The unit comprises a first cutter which functions as a cutter for trimming a veneer sheet and a second cutter which extends from one or both sides of the blade of said first cutter. During a trimming action of the first cutter, the second cutter cuts in the veneer sheet at its butt ends newly formed by the first cutter. The thus obtained veneer sheet is ready for any reinforcing step. However, if the first and second cutters are additionally provided with a hole to pay out a cord therethrough, the cut formed in the butt end of the veneer sheet firmly hold the cord since the veneer sheet has a tendency to close the cut after the passage of the second cutter, providing a reinforced veneer sheet.

Abstract: An improved veneer lathe which cuts off a sheet of veneer from a log supported rotatably by applying a torque directly to the outer periphery of the log. An external force for cutting the log is fed from the vicinity of a knife included in the lathe. The log core is not subjected to a load attributable to a cutting resistance so that even logs of a poor quality are usable for turning veneer sheets therefrom, enhancing the yield of plywood production.