Abstract: A block of user data is formatted by arranging the user data block into a byte array having plural rows and plural columns of bytes. An error correction code is applied to individual ones of the rows of bytes, such that each row has four code words.

Abstract: In a shredding machine having contra-rotating cutter shafts (16,17) carrying cutters (18), one shaft (16) is at a lower level than the other and the side of the shredding chamber (12) alongside the lower shaft has an ejection chute (71) for intractable material. The chute is normally closed by an access door (74), which when open allows the intractable material to be ejected by reversal of the lower shaft (16). The feed hopper (13) has internal doors (80,81) movable to position obstructing the feed when intractable material is to be cleared from the cutters. An automatic, sequential control system is preferably provided for opening and closing the access door and hopper doors in conjunction with a reversing sequence for the cutters.

Abstract: A rotary shredding machine having a comminuting chamber within which is a pair of parallel cutter shafts arranged for simultaneous contra-rotation and a plurality of cutters secured to each of the shafts, each cutter being a generally disc-like body having at least one radially projecting peripheral tooth provided with a cutting edge along a leading edge thereof, each disc-like body defining a coaxial shaft aperture receiving an associated shaft with both the shafts and the apertures being substantially square in cross-section with straight sides, the cutting edge of each tooth being intersected by a radial plane inclined at an angle in the range of 0.degree. to 60.degree.

Abstract: A cutter for a rotary shredding machine which includes a disc-like body defining a coaxial shaft aperture therethrough adapted to accommodate a rotary shaft which defines a cutting axis, the body including a plurality of cutter body members and releasable fastening means for holding the body members together with at least one of the body members having a radially projecting tooth including a cutting edge along a leading edge thereof, each cutter body member having two first surface portions extending chordally from the body periphery and joined by a second surface portion adapted for engaging a shaft, the second surface portions together defining the shaft aperture, and each first surface being juxtaposed with, but spaced from, a parallel, corresponding first surface portion of the next adjacent body member thereby to permit limited tilting movement of the toothed body member circumferentially about the cutter axis with simultaneous momentary deformation of that body member when a sufficiently high impact for

Abstract: A phonograph has a viscous damping arrangement coupling a pick-up arm to the base of the phonograph to damp vertical and horizontal vibrations of the arm. The damping means is coupled to the arm at a position close to the pick-up cartridge of the arm. A counter-balance mass is also provided on the arm, the mass having an adjustable position and mass.