Abstract: A boiler water level system comprises a plurality of electrodes arranged to sense the resistivity of the fluid at each of a plurality of different levels in a pressure vessel. The pressure vessel is coupled to one end of the boiler such that the level of the water in the pressure vessel is substantially the same as the level in the boiler, and each electrode senses the resistivity of the fluid (ie water or steam) between the tip of the electrode and the wall of the pressure vessel. Such a system on its own inherently produces a digital output of relatively low resolution, so to improve resolution, and to provide an analogue output if desired, additional circuitry is provided to sense the progressive change in the impedance sensed by each electrode as the water rises to progressively immerse that electrode and then carries on rising towards the next electrode.

Abstract: A signature booklet maker (SBM) finishing apparatus for an image producing device includes a modified fold blade having a plurality of contacting teeth spaced part by a predetermined distance. The contacting teeth further include a predetermined contact surface width and a predetermined thickness. The grind direction of the teeth is specified to reduce inside sheet drag during folding. The spaced teeth are adapted drive the stitched signature set in a folding unit without contacting the stitches, thereby eliminating fold skew and inside sheet marking. Moreover, the fold blade has a predetermined hardness to ensure that the blade is not damaged during folding. The SBM further includes a trim waste elimination device and knife guard to prevent booklet trimmings from migrating throughout the trimmer unit. The knife guard eliminates the safety hazard caused by the blade in the resting position and guides air from an air blower to force booklet trimmings into a waste chute.

Abstract: A multi-mode apparatus for ejecting individual sets of compiled, attached or unattached sheets to substantially the same location for any size sheet from a electrophotographic printing machine to an off line finishing device without impairing the process speed thereof. In a first mode each sheet set is compiled on a moveable member. The moveable member is then translated by actuating a pneumatic cylinder to translate the compiled sheet set to a location external of the compiling apparatus. A vertically moveable bail device applied a normal force to the sheet set to maintain the integrity of the set during transport but is substantially frictionless so as to not disturb the registration of the sheet set. The translating member is able to quickly transport a compiled set of sheets from a location internal of the compiling device to an external location whereat the sheet set may be fed to an off-line other finishing or processing device.

Abstract: A signature booklet maker (SBM) finishing apparatus for an image producing device includes a modified fold blade having a plurality of contacting teeth spaced part by a predetermined distance. The contacting teeth further include a predetermined contact surface width and a predetermined thickness. The grind direction of the teeth is specified to reduce inside sheet drag during folding. The spaced teeth are adapted drive the stitched signature set in a folding unit without contacting the stitches, thereby eliminating fold skew and inside sheet marking. Moreover, the fold blade has a predetermined hardness to ensure that the blade is not damaged during folding. The SBM further includes a trim waste elimination device and knife guard to prevent booklet trimmings from migrating throughout the trimmer unit. The knife guard eliminates the safety hazard caused by the blade in the resting position and guides air from an air blower to force booklet trimmings into a waste chute.

Abstract: A distributed temperature sensor comprises an elongate ultrasonic waveguide having a number of zones along its length, each zone having a grating formed on it. This is typically achieved by incorporating uniformly spaced notches or bands (or collars) throughout the zone. The grating spacing in each zone is different, so that each grating reflects a characteristic frequency. This frequency varies as the temperature of the zone varies, so if wide-band ultrasonic pulses are launched into the waveguide, the temperature of each zone can be determined from the reflected frequencies.

Abstract: A water level measurement system for use with a pressurized power plant boiler comprises a tubular pressure vessel for attachment to one end of the boiler such that the water level in the pressure vessel is the same as in the boiler. The pressure vessel has a central rod-like conductor which together with the vessel forms a coaxial RF waveguide. A pair of spaced reference discontinuities are provided in the conductor above the maximum level of the water, so that an RF pulse injected into the waveguide is reflected successively by both discontinuities and the surface of the water. The level of the water can then be determined independently of changes in the dielectric constant of the vapor above it, from the ratio between the time intervals between the first and second reflected pulses and between the first and third reflected pulses. The conductor is mounted at the top of the pressure vessel by way of a pressure seal and a ceramic insulator.

Abstract: A binding tape cartridge in which a reel of binding tape is packaged in a moisture impervious bag. The bag has an exit port through which the tape is advanced. A seal, mounted in the exit port, permits the passage of tape therethrough while maintaining the interior substantially dry. This projects the binding tape from moisture, reducing the possibility of tape delamination.

Abstract: A shaft monitoring system for sensing axial movement of a shaft, especially in a gas turbine engine, comprises a toothed wheel attached to and rotatable with the shaft, and a pair of inductive sensors disposed radially of the toothed wheel for sensing the passage of the teeth as the shaft rotates. In one embodiment, the toothed wheel has two axially-spaced sets of teeth, one set straight cut and the other set diagonal cut, so that the phase difference between the respective outputs of the sensors varies with axial movement of the shaft. In another embodiment, the sensors are positioned at opposite axial ends of the toothed wheel, so that axial movement of the shaft causes one sensor output to increase in amplitude while the other decreases.