一摇动手摇器时看看是否轻巧、有无噪音等,普通升降晾衣架内部采用前后塑料代替或是前塑料后轴承构成,容易塑料老化变质,造成升降困难,摇动时费力甚至摇晃。质量可靠的晾衣架则由前后四轴承组成,在升降过程中更加轻便顺畅,无异响,从而增加产品的使用寿命。 When shaking the hand crank to see if it is light, with or without noise, the normal lifting racks instead of front or rear plastic instead of or before the plastic bearings, easy plastic aging deterioration, resulting in difficult to lift, shaking or even shaking. Quality and reliable drying racks by the front and rear four bearings, the lifting process more portable and smooth, no abnormal sound, thereby increasing the service life of the product.