Generally, a dishwasher is an electric appliance configured to wash or dry objects, namely, dishes held in a washing room by using washing water.
FIG. 1 is a diagram of a conventional dishwasher. Such a conventional dishwasher includes a cabinet 200 in which a tub 210 for providing a washing room is arranged, upper and lower racks 220 and 230 provided in the tub to place washing objects thereon, a sump 240 arranged under the tub 210 to store the washing water therein, a lower arm 260 for injecting the washing water toward the lower rack, an upper arm 250 for injecting the washing water to the upper rack, a pump (P) for supplying the washing water stored in the sump 240 to the lower arm 260 via a first passage (P1), and a second passage (P2) branched from the first passage through a valve (V) to supply the washing water to the upper arm 250.
The sump 240 is supplied with the washing water via a water supply passage 241 and it has the washing water held therein drained via a drainage passage 243. The second passage (P2) is supplied the washing water drawn via the first passage (P1) to supply the washing water to the upper arm 250.
The upper arm 250 provided in the conventional dishwasher may be arranged between the upper rack 220 and the lower rack 230, to wash the washing objects held on the upper rack. Accordingly, a predetermined space is provided between the upper rack 220 and the lower rack 230 to arrange the upper arm 250 therein.
The size of an object that can be placed in the racks 220 or 230 may be limited by the placement of the upper arm 250. Furthermore, the size of the racks may be limited by the presence of the upper arm 250.
Moreover, the second passage (P2) may limit the size and position of the racks 220 and 230.