Abstract: Provided is a drum-type washing machine having a rotatable viewing window comprising: a front panel of the housing of the washing machine, an access opening provided on the front panel, and a viewing window disposed on the access opening, wherein a hinge component is provided between the viewing window and the front panel of the housing to allow the rotation of the viewing window along a horizontal orientation and along a vertical orientation to the open position. When the viewing window opened to a small degree along the horizontal direction, it then could rotate upwards to open, and accordingly nearly half the space occupied by opening the viewing window of traditional front loading washing machine could be saved. Furthermore, the automatic opening could be achieved.

Abstract: Disclosed is a superposed heat exchanger, including a plurality of fins superposed up. Two opposite side edges of each fin are bent upwards to form a ventilating air path in coordination with an upper fin, and adjacent fins are arranged in a mode of vertical-horizontal alternating so as to form horizontal air paths and vertical air paths independent from each other with up-down intervals.

Abstract: Disclosed is a dryer or a washer dryer, including at least a clothes drying system, where the clothes drying system includes a heating structure and a condensing structure; the condensing structure is arranged on a lower part of the dryer or the washer dryer; the condensing structure includes an air inlet and an air outlet for hot air, and further includes a gas inlet and a gas outlet for cold air, and a heat exchanger is arranged inside the condensing structure; the heat exchanger is composed of fins which are superposed in a longitudinal-transverse alternating manner, and a frame with an enclosure structure is arranged outside the heat exchanger.