Abstract: A polarizing monochromator comprising a uniaxial birefringent crystal prism, the prism has the geometry of a triangular block having a triangular base, a face including a side of the hypotenuse is an input-output face, where light enters and exits, and a face including the longer side of the right angle is a reflection face, the optic axis of the prism is perpendicular to the base of the prism, the angle of the input-output face of the prism with respect to light coming from a collimator optical system is determined in such a manner that ordinary light and extraordinary light exit from the input-output face of the prism in opposite directions with respect to an optical axis connecting the collimator optical system and the prism, and a light-collecting optical system is disposed to collect either extraordinary light or ordinary light exiting from the input-output face of the prism.

Abstract: A polarizing monochromator comprising a uniaxial birefringent crystal prism, the prism has the geometry of a triangular block having a triangular base, a face including a side of the hypotenuse is an input-output face, where light enters and exits, and a face including the longer side of the right angle is a reflection face, the optic axis of the prism is perpendicular to the base of the prism, the angle of the input-output face of the prism with respect to light coming from a collimator optical system is determined in such a manner that ordinary light and extraordinary light exit from the input-output face of the prism in opposite directions with respect to an optical axis connecting the collimator optical system and the prism, and a light-collecting optical system is disposed to collect either extraordinary light or ordinary light exiting from the input-output face of the prism.

Abstract: An apparatus for splitting a wood board into two separate sheets, comprising a pair of parallel drive shafts rotatable in the opposite directions, a series of toothed wheels fixed on each of the drive shafts at a predetermined spaced interval, each toothed wheel having on the circumferential periphery thereof a number of teeth incisingly engageable with the board, the toothed wheels on one of the drive shafts being disposed radially in alignment with the toothed wheels on the other drive shaft, respectively, a knife having a cutting edge positioned and directed to split the board from end to end into two separate sheets. The tip end portions of the teeth of each two radially aligned toothed wheels is formed to be positioned in an offset relation in the axial direction of the drive shafts by forming the tip end portion to have at least one surface which is bevel or oblique with respect to a plane extending radially of the toothed wheel.

Abstract: A rotatable roll is provided under a planing cylinder rotating at a fixed position. A front feed unit and a rear feed unit having an upper and a lower roll for gripping the plate are provided upstream and downstream of the planing cylinder with respect to the feed direction of the plate. A front movable body and a rear movable body having an upper and a lower roll for gripping the plate member are provided between the planing cylinder and the front feed unit and between the planing cylinder and the rear feed unit. The upper and lower rolls of the front and rear movable bodies are forcibly moved up and down. The plate member is supported at three points and deflected downward to prevent floating of the plate during cutting and to prevent the formation of depressions in the plate near its front and rear ends during cutting.

Abstract: An unseasoned veneer bonding method and an apparatus therefor capable of bonding unseasoned veneers to each other without being affected by the moisture content of the unseasoned veneers and with ease. The unseasoned veneer bonding method comprising the steps of: machining an end portion of at least one unseasoned veneer of unseasoned veneers with prescribed thickness to be bonded to form a portion thinner than the prescribed thickness; overlapping the thinner portion of the one unseasoned and an end portion of the other unseasoned veneer to each other through thermosetting bonding agent; and press-contacting a heating body to at least the thinner portion.

Abstract: A method for preparing a laminate including pressing a heater against the upper and lower surfaces of a veneer during which an inner portion of the veneer in the thickness direction is dried to the smallest extend then the surfaces so that a water content of the inner portion is kept higher than that of the surfaces, dividing the veneer in terms of its thickness into two counter veneers, placing a ligneous board between the counter veneers using an adhesive so that the surfaces resulting from the diving are disposed as outer surfaces, and pressing a heater against the outer surfaces to effect bonding of the counter veneers and the ligneous board.

Abstract: A method for bonding wood plies together comprises the steps of (i) forming passages in at least one of faces of the wood plies, except faces thereof for providing opposed faces of a bonded wood product, (ii) placing the wood plies on one another with a thermosetting adhesive material or materials between, and (iii) pressing the wood plies together transverse to the opposed faces of the wood plies, while blowing a heating fluid into the passages to heat and harden the adhesive material or materials. The passages should preferably be evenly distributed on the face of the wood ply to uniformly heat and harden the adhesive material According to one embodiment of the invention, the passages extend from one edge of the wood ply to an opposed edge thereof. Steam or hot air may be used as the heating fluid.

Abstract: The invention provides an improved planar which effectively prevents undesirable torn grain. The planer of the invention includes at least one planer knife or blade and at least one pressing member, both attached to and supported on a cutterhead. The pressing member includes a head element which is located to have a predetermined angle with respect to the blade and is resiliently movable in a predetermined direction to press an edge of the head element against a certain position of a wood surface immediately before a cutting edge of the blade moving in a fixed direction for cutting or against a boundary between the wood surface and a chip being currently cut from the wood surface. The direct pressing of the pressing member against the wood surface prevents rise of wood fibers and thereby effectively reduces or eliminates undesirable torn or chipped grain.

Abstract: A substantially uncurved and unwaved plywood includes at least one pair of veneers located symmetrically with respect to a middle of a thickness of the plywood and having unstraight grains which coincide with each other.A method for producing a substantially uncurved and unwaved plywood comprises locating at least one pair of veneers with identical unstraight grains in a pair of positions symmetrical with respect to a middle of a thickness of a plywood to be produced, in such a manner than the grains of the veneers coincide with each other.

Abstract: A veneer sheet having lathe checks is pressed in at least one of two opposite directions in the same plane as the veneer sheet itself and substantially perpendicular to the directions of its fibers, while another sheet is being bonded to at least one of its two oposite sides, namely, its tight side having no lathe checks and its loose side having the lathe checks. Before the veneer sheet is pressed in this manner, glue may or may not be filled into the lathe checks thereof. Or glue is filled into the lathe checks of the veneer sheet, and is merely hardened, without bonding no other sheet thereto, while the sheet is being pressed in at least one of the foregoing two opposite directions.

Abstract: Improved and novel structure of plywood is disclosed which makes it possible to use such veneers that are too short for a desired length of plywood panel and to provide joint which can exhibit improved strength over heretofore. The plywood of the invention includes a standard portion where a required number of plies of veneer are laminated together and at least one joint portion where short veneers in any of said plies are lapped at their adjacent longitudinal ends.

Abstract: A veneer lathe for turning the log by means of a rotary roller which is capable of continuing the cutting operation until the log being cut comes to have a diameter practically the same as the spindle diameter. Said veneer lathe comprises a boring unit, centering unit, a spindle conveying mechanism for conveying the log from the boring unit to the spindle means, rotary drive roller to turn the log and means for guiding the spindles and stopping the log movement. The log is formed with center bores by the boring unit. Through said center bores, the spindles are inserted to prevent the log from deflecting under the pressing force of the rotary roller. Upon completion of the turning operation, the spindles are removed out of the centerbores while the spindle guiding and log stopping means prevents the log from following the spindle removing action.

Abstract: A veneer lathe for turning a log thereon to cut off veneer sheets therefrom. The log is principally driven by a rotary roller having a plurality of projections therearound, which roller is pressed against the log to ensure positive engagement with the periphery thereof. The log is formed with a center bore at a core portion thereof. A spindle to support the log is inserted into the center bore to prevent the log deflection due to the pressure from the rotary roller. Another form of this veneer lathe is additionally provided with a center bore forming mechanism together with a centering mechanism for the boring operation such that a center bore is formed in the log in advance before being turned on the veneer lathe.

Abstract: A cord burying apparatus for a veneer sheet is provided. The apparatus comprises a cord burying knife and a piercing element having a plurality of piercing members thereon and provided on one side of the cord burying knife in axial juxtaposition therewith relative to the log. The cord burying knife has an edge facing upstream with respect to the log rotation to come into a cutting engagement with the log. The piercing members on the piercing element also come into cutting engagement with the log to positively move the log past the knife. The provision of the piercing element facilitates cutting operations of a log having rotten portions.

Abstract: A method of mending a veneer sheet having a defective portions is provided. An imcomplete veneer sheet and a sheet of mending material is laid one on top of the other. They are cut through by a single stroke of a annular cutting tool such that the defective portion of the veneer sheet is cut off whereas a plug having a same size and shape as the cut-off defective portion is cut out. They are retained in the annular cutting tool until the plug is shifted into a plane in which the veneer sheet extends. At the same time, the cut-off defective portion is removed from the veneer sheet. Then, when the cutting tool is removed from the sheets, a mended veneer sheet results.Another method is also provided. A plurality of plugs are cut out from a sheet of mending material by repeatedly cutting through it by a single annular cutting tool. The cut-out plugs are retained in the annular tool.

Abstract: A method of reeling and unreeling a reinforced veneer sheet is provided. A veneer sheet peeled off from a log on the veneer lathe is subjected to a reinforcing step, in which an elongated cut is formed on one side of the sheet across the grain and a length of cord is embedded in it. In a reeling operation, the reinforced veneer sheet is wound onto the reel with its cut side facing radially outward. In an unreeling operation, on the other hand, the sheet is unwound from the roll with its cut side facing downward. This method prevents the embedded cord from slipping out of the engagement with the elongated cut during the reeling and unreeling operations.

Abstract: A veneer sheet reinforced with at least one piece of cord is provided. The cord is thrust through the sheet at appropriate intervals and projects from either side of the sheet. The projecting portions are fastened by deforming the cord or applying an adhesive including a thermoplastic resin, a thermosetting resin, and a wet-setting resin.

Abstract: An improved veneer lathe which cuts sheets of veneer from a turned log. A torque is applied to the log both by way of the spindle chuck holding its axial ends and by way of its outer periphery. During the cutting operation, the primary cause of log rotation is designed to be an external force applied to the log periphery by using an idling mechanism including a torque limiter, an overrunning clutch, etc.

Abstract: An improved veneer lathe which cuts sheets of veneer from a turned log. A torque is applied to the log both by way of the spindle chuck holding its axial ends and by way of its outer periphery. During the cutting operation, the primary cause of log rotation is designed to be an external force applied to the log periphery by using an idling mechanism including a torque limiter, an over-running clutch, etc.