To prevent the error of rearrangement by providing a collection section with a fill-up detecting means for detecting that the collection section is filled up and a remaining detecting means which detects that articles remain in the collection section, thereby taking out the whole of letters in a collecting means.

When the fill-up detecting means 107 detects the fill-up of the collection section, fill-up processing is started. When an operator takes out the letters 1 of the collection section, the fill-up detecting means 107 does not detect the fill-up any more. When the remaining detecting means 110 detects the letters 1, the fill-up processing is continued on decision that the letters 1 still remain in the collection section. When the remaining detecting means 110 detects the absence of the letters 1 in the collection section, the fill-up processing is stopped and the feeding of the letters 1 to the collection section is started. The letters 1 are surely taken out by using the remaining detecting means 110 to establish the stop conditions of the fill-up processing in such a manner and the rearrangement in erroneous order may be prevented.