The Type 77 Electric Punched Card Collator performs many card filing and pulling operations. As a filing machine, the Collator feeds and compares simultaneously two groups of punched cards: records already in file, and records to be filed. These two groups are merged in correct numerical or alphabetical sequence. If desired, the machine will at the same time remove from either group, those cards which are matched by cards in the other group, or all but those cards which are matched, or other selected cards.

When operated for the purpose of pulling cards, the Collator makes it possible for one group of cards to pull corresponding cards from another group. The cards not pulled are segregated for return to the file, and the absence of any cards sought is indicated by segregation of the corresponding pulling cards. The cards pulled and those which pull them may be kept separate, or merged in sequence, as required.

Many operations, previously performed less efficiently, are made automatic by this machine. Following is a brief list of applications:

Filing current transaction cards with previous transaction cards.

Pulling accounts receivable debit cards and combining them with cash received credit cards.

Replacing old record cards with new record cards superseding them.

Selecting all cards dated earlier than a certain date, as for analysis of accounts in arrears, or all cards containing a given classification number, when cards are scattered throughout the file.

Combining master cards, such as name and address and rate cards with transaction cards and separating them again after their use in accounting machine operations.