Abstract: A self-centring compact coupler for lifting, jacking or pushing apart and positioning concrete elements via their reinforcement bars (rebar) having an adjusting coupler member screwed on a threaded post attached to one rebar to apply a lifting or pushing force against a non-adjustable seating stud with an integral seating head and centring protrusion fixed to a corresponding and opposite rebar. An enclosing coupler member is screwed on the adjusting coupler member to enclose and lock the seating head and couple the rebar. The unitary configuration of the seating stud and seating head reduces the number of parts. The centring facility negates need of large internal tolerances to accommodate rebar misalignment, thus substantially ensuring co axial transfer of force from the coupler to the rebar. The coupler is used to incrementally vary and accurately adjust the relative positions of the concrete elements to one another in the building process.

Abstract: A self-centring compact coupler for lifting, jacking or pushing apart and positioning concrete elements via their reinforcement bars (rebar) having an adjusting coupler member screwed on a threaded post attached to one rebar to apply a lifting or pushing force against a non-adjustable seating stud with an integral seating head and centring protrusion fixed to a corresponding and opposite rebar. An enclosing coupler member is screwed on the adjusting coupler member to enclose and lock the seating head and couple the rebar. The unitary configuration of the seating stud and seating head reduces the number of parts. The centring facility negates need of large internal tolerances to accommodate rebar misalignment, thus substantially ensuring co axial transfer of force from the coupler to the rebar. The coupler is used to incrementally vary and accurately adjust the relative positions of the concrete elements to one another in the building process.

Abstract: An apparatus for aligning and joining construction elements comprising threaded studs or bars protruding from opposing elements; interlocking members adapted to screw together associated with each of the opposed studs; an adjustment nut screwable on one of the studs wherein, the adjustment nut is screw jacked against one of the interlocking members to align the elements and then locked and encapsulated by screwing together the interlocking members. There can be additional stud or bar alignment means associated with the apparatus.

Abstract: An apparatus for aligning and joining construction elements comprising threaded studs or bars protruding from opposing elements; interlocking members adapted to screw together associated with each of the opposed studs; an adjustment nut screwable on one of the studs wherein, the adjustment nut is screw jacked against one of the interlocking members to align the elements and then locked and encapsulated by screwing together the interlocking members. There can be additional stud or bar alignment means associated with the apparatus.

Abstract: A digitizer suitable for digitizing input signals having a high dynamic range. The digitizer is microprocessor controlled and comprises an input stage, a multi-channel attenuator or amplifier bank, a multiplexer and a analog-to-digital (A/D) converter. The function of the multi-channel bank is to move the input signal within the range of the A/D converter. The input signal to be digitized is fed through the input stage to each of the channels in the attenuator bank. The signal is scaled by each respective channel in the attenuator bank. The multiplexer is used to switch the scaled signal which is within the range of the A/D converter for digitizing. The digitized sample is then corrected according to the attenuation or gain factor of the scaled channel. The digitizer includes a comparator bank which is used to determine the channel with the widest signal range within the range of the A/D converter. The digitizer also includes a channel calibrator for calibrating the actual gain or attenuation of each channel.