Abstract: Fines, pins, and over-thick wood chips are separated from wood chip material by using a series of three roller screens having chip agitating and conveying protuberances. The screens are arranged and adapted such that over-thick chips are separated by the first screen, fines are separated by the second screen, and pins are separated by the third screen.

Abstract: Wood chips having an acceptable thickness pass between the rollers of a roller screen for collection and over-thick chips discharge from one end of the roller screen for recycling. The rollers have chip agitating protuberances, preferably of pyramidal shape or in the form of spiral ridges. A second roller screen with pyramidal protuberances on its rollers and with its rollers closer together is used to screen out fines, preferably after the fines and acceptable chips pass through the first roller screen. Some of the fines pass through the second roller screen by occupying the valleys between the pyramidal protuberances.

Abstract: The anvil rotor on a wood chip slicing machine is connected to its drive shaft via shear pins which extend into the hub of the rotor from a coupling which is mounted on the shaft. The coupling provides bearings for rotation of the rotor hub thereon when the shear pins are sheared as a consequence of an overload or load shock condition. The overload protection mechanism is applicable to other machines.

Abstract: Wood chips having an acceptable thickness pass between the rollers of a roller screen for collection and over-thick chips discharge from one end of the roller screen for recycling. The rollers have chip agitating protuberances, preferably of pyramidal shape or in the form of spiral ridges. A second roller screen with pyramidal protuberances on its rollers and with its rollers closer together is used to screen out fines, preferably after the fines and acceptable chips pass through the first roller screen. Some of the fines pass through the second roller screen by occupying the valleys between the pyramidal protuberances.

Abstract: Fines are separated from wood chips by feeding the chips onto the infeed end of a bed formed by a plurality of knurled rollers separated by narrow gaps and rotated in the same direction. The chips are tumbled by the knurls, and the fines settle into the spaces between the knurls and in the gaps to pass downwardly out of the bed for collection. As the chips tumble, they gradually move to a discharge end of the bed and discharge for further processing.

Abstract: Wood chips are debarked by compacting them in a mass, and agitating the compacted mass. In the compacted mass the chips are caused to rub against one another so that the bark is removed from the chips by rubbing friction of chip against chip. Frictional pressure on the removed bark finely comminutes the bark for easy separation from the debarked chips. The compacting and agitating of the chip mass is effected by a rotor device in a debarking drum chamber.

Abstract: A contaminant sorting device for sorting contaminant material, such as metal and rocks, from processing materials, such as wood chips, comprising a housing having internal walls formed of a surface of revolution into which housing is fed processing material at the upper portion thereof, an impeller disposed in the housing for receiving processing material and propelling it radially outwardly against the inner surfaces of the housing walls, a plurality of vibration sensing devices disposed around the walls of the housing for sensing vibrations due to impingement of the processing material on the walls, an electrical circuit for distinguishing between signals generated in response to impact of the processing material from response to impact of contaminant material, a series of trap doors each associated with a corresponding vibration sensing device and disposed downstream in the material flow path for diverting from the normal flow path a portion of processing material containing contaminant material.

Abstract: A contaminant sorting device for sorting contaminant material such as metal and rocks from process materials such as wood chips which are intended to be subsequently processed, comprises a material receiving surface upon which a layer of material is deposited which material contains both contaminant and process material, an impact sensing device for sensing vibrations of the material receiving surface upon impact of the material thereon, an electronic circuit for distinguishing between signals generated by impact of contaminant material from signals generated by impact of process material and for providing an output signal in response to receipt of a contaminant material signal, a flow diverting plate downstream from the material receiving surface which is activated by the signal produced in response to impact of the contaminant material so that the normal flow path of the layer of material is interrupted so as to divert that portion of material containing contaminant material to a separate receptacle, and ti