Abstract: A cradle has wheels and suspension system and channels or raceways and blocks or a brake for maintaining the cradle in a stationary position relative to the ground during loading and unloading. A load bed with top loading ramps and a bottom pair of wedge slide ramps rides on the raceways pushed and pulled by a tow arm from a towing vehicle. The wedge slide ramps provide a vertical cam action gradually elevating a forward end of the load bed as the wedges move onto the raceways for tilting the load bed so that the back end of the loading ramps tilt down to contact the ground for loading.

Abstract: In a humidifier, an evaporator has a vessel containing two or more spaced vertical electrodes across which a voltage can be applied. The current which flows depends on the cross-section of the immersed portion of the electrodes, the size, shape and spacing of the electrodes, the applied voltage and conductivity and volume of the water. The invention provides a probe for measuring the conductivity of the water in the vessel and replacing some of the water in the vessel with fresh water when necessary to reduce the conductivity to the value for which the evaporator is designed. The probe may be connected directly into the evaporator or it may be connected to a voltage source so that a current dependent on the water conductivity will flow between these electrodes.

Abstract: A water vapor generator having electrodes in a vaporization vessel is disclosed. Current passed through the water between electrodes causes water in the vessel to heat and boil off as steam, make-up water being added when the current drops below a preset minimum value. The make-up water is cut off when a preset maximum value is reached. Thus, the generator operates through successive cycles each containing a descending "boil" leg and an ascending "fill" leg. As water is boiled, its mineral content becomes more and more concentrated, causing increasing its conductivity. To return the water conductivity to its design value the frequency of the boil/fill cycles is measured over several cycles and compared with a predetermined value. If the measured frequency is higher, this indicates a higher than desired water conductivity and a drain cycle is initiated by operating a drain valve. The amount of water drained out of the vessel is proportional to the deviation of frequency from the predetermined value.