of excess moisture the device is more particularly applicable to the field of the textile industry in particular the field of washing and or dying yarn application_number US 72879896 A description according to the invention and as shown more particularly by way of example in fig1 and 2 of the accompanying drawings the yarn expression device is essentially constituted by a comb 1 for guiding and expressing individual yarns of a layer of yarn and by compressed air blowing means 2 in line with each interval between two teeth 3 of said comb 1 this air blowing means 2 coacting with the comb 1 to effect expression of excess moisture the comb 1 is preferably constituted by an assembly of teeth 3 and spacers 4 disposed between said teeth 3 and by at least one gripping spindle 5 for said teeth 3 and spacers 4 on a support 6 fig1 and 2 such a construction of comb 1 permits easy adaptation of the latter to a predetermined number of yarns of a layer by simple demounting of the spindle 5 from the support 6 and mounting or unmounting the necessary number of pairs of teeth and spacers then remounting the spindles 5 in the new arrangement on the support 6 the teeth 3 are preferably in the form.