To eliminate the need for work of placing wash on a weighing apparatus and measuring its weight and to improve the effeciency of laundry work by acquiring the identification information on the wash by an identification information acquiring means, then reading out the weight of the wash from a weight information memory means and subjecting the weight to sequential cumulative total processing.

An ID tag having a coil for antenna for transmitting and receiving radio wave signals, a resonance capacitor, an IC for control, etc., is attached to an article, such as uniform to be lent to a hospital, hotel, etc. A reader/writer 11 is disposed near the terminal of a first conveyor 8 into which the recovered article 1 is carried so that the radio wave signals from the ID tag of the article 1 falling into a housing case 10 from the conveyor 8 is made readable. The information of the article is read out by an MPU from the result of the reading and the weight is detected. The weights of the successively fed articles are thereafter added and when the total weight attains a regulated value, a second conveyor 9 is driven and the housing case 10 is carried into a laundry machine 6, and the washing is executed.