Abstract: A rotary machine tool, such as a grinding wheel, is mounted on a movable support serving to advance the tool toward a workpiece, such as a pipe to be severed thereby. The tool is driven by an electric motor whose operating current is measured by a sensor controlling the fluid supply to a hydraulic servomotor which is linked with the support. When the advance is too rapid, the resulting rise in load resistance increases the operating current and causes a throttling of the fluid pressure, the rate of advance being thus optimized in conformity with the shape and/or composition of the workpiece.

Abstract: An article of food is heated in an oven in which air is circulated. Moisture in the form of steam or a water spray is added to the air as it circulated several times during the cooking or thawing cycle according to a program. Each moisture dose and the length of the interval between doses is controlled independently according to the treatment desired. The first dose is made after the cooking cycle is started, and the dosing time is usually a fraction of the time between doses.

Abstract: A food cooking oven has a closed muffle in which there is provided an axial-input radial-output blower that is rotated by a drive motor outside the housing so as to circulate gases in the housng in a closed path passing through the blower. At least one vane is provided in the housng at one of the sides of the blower so as to limit air circulation therein and prevent excessively strong currents of air in the housing from damaging delicate foodstuffs. This may be a disc vane in front of the axial input of the blower or a pair of elongaged vanes flanking the blower at the output sides thereof.

Abstract: A trash compactor has a wheeled housing with a laterally accessible compaction chamber wherein a vertically movable pressure plate is carried on a plurality of inflatable bladders which are suspended from the ceiling of the chamber. A gas bottle carried underneath the chamber bottom is connectable via a control valve to these bladders so as to expand them, pushing the pressure plate downwardly to compress loose trash in the compaction chamber. A plurality of cables connected to the corners of the pressure plate pass upwardly into a control compartment where they are led about rollers carried on piston rods of pneumatic cylinders also connectable by the valve to the gas bottle so as to allow these pistons to pull the pressure plate into an upper position at the top of the compaction chamber.