Abstract: A power converter includes a converter, a smoothing capacitor, an inverter, and a single calculator. The converter includes a switching element and rectifies a power supply voltage applied from an alternating-current power supply. The smoothing capacitor smooths a rectified voltage output from the converter into a direct-current voltage including a ripple. The inverter converts the direct-current voltage smoothed by the smoothing capacitor into an alternating-current voltage for a motor. The calculator performs control such that a first physical quantity representing an operation state of the converter is equal to a second physical quantity representing an operation state of the inverter.

Abstract: The present invention relates to a liquefying alkaline .alpha.-amylase having the enzymatic properties described below, a production process thereof and a detergent composition containing the same.1) Action:It hydrolyzes .alpha.-1,4-glucosidic linkages in starches, amylose, amylopectin and partial degradation products thereof and from amylose, forms glucose (G1), maltose (G2), maltotriose (G3), maltotetraose (G4), maltopentaose (G5) and maltohexaose (G6). It however does not act on pullulan.2) Isoelectric point:It has an isoelectric point higher than 8.5 when measured by an isoelectric focusing electrophoresis.The amylase according to the present invention has a liquefying activity capable of permitting degrading starches and starchy polysaccharides at high random, and has an optimum pH on the alkaline side. Owing to the high isoelectric point, it can be purified readily. Detergents with the amylase incorporated therein have excellent detergency especially against the soil of smeared food.

Abstract: A magnetic belt conveyor type magnetic particle separator comprises a storage tank for storing cutting oil containing magnetic particles, an endless belt conveyor extending sidewise from the storage tank in an upwardly inclined direction, and a magnet disposed beneath the forward run of the belt conveyor to extend in the direction of running thereof. Magnetic particles contained in the cutting oil are attracted by the forces of the magnet to the upper surface of the forward run of the belt conveyor to be conveyed up to the forward run end thereof and separated therefrom at the forward run end for being discharged.