A known adjustment device for adjusting the abutments in a large-size high-rate folding machine consists of an arrangement of strips. Each strip carries an abutment and may be manually moved in translation along rails provided on the longitudinal edges of the document guide plates. The abutment is adjusted by displacing the strip and locking it in the desired position.
This type of device requires sufficient free space for providing access to the strips. In compact and medium-size folding machines, the amount of free space available is such that it is impossible or difficult to insert a hand so as to access the abutment.
Moreover, folding machines are often associated with mechanisms for inserting the document into an envelope and for closing the envelope, which mechanisms require space in the machine and reduce the availability of access to the various portions of the folding machine.
A folding machine having pockets is described in French Patent Application 90 13580. Such a folding machine includes a top pocket for making a first fold, and a bottom pocket for making a second fold. Each pocket includes a fixed plate and a central plate that moves.
Each of the central plates supports an abutment which is adjustable in translation along its pocket, so as to select the positions of the first and second folds in the document. Such a folding machine is designed to be followed by a mechanism for inserting the document into an envelope and for closing the envelope.
An aim of the invention is to provide an adjustment device for adjusting the positions of the abutments, in particular for such a machine, with the access and maneuverability of the adjustment device being particularly practical and reliable.