Absorption-type unit concentrated solution bypass defrosting device

The invention provides an absorption-type unit concentrated solution bypass defrosting device. The absorption-type unit concentrated solution bypass defrosting device comprises a medium flow-in pipeline and a medium flow-out pipeline. The medium flow-in pipeline comprises an absorber, a concentrated solution flowing direction control device and a liquid distributing device, wherein the absorber isused for containing a concentrated solution medium; the concentrated solution flowing direction control device is connected with the absorber, a casing pipe and the input end of the liquid distributing device through pipelines; and the output end of the liquid distributing device is used for being connected with an evaporator of a heat pump unit. The evaporator comprises an air-cooling finned heat exchanger. The air-cooling finned heat exchanger comprises a finned tube. A heat exchange coil pipe and a defrosting coil pipe are arranged in an inner cavity of the finned tube. The defrosting coilpipe is attached to the h