Watkiss Automation Plockmatic PowerSquare 224, Workbook

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Description of Operation
Plockmatic PowerSquare™ 224 - Service Training Workbook
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The set is moved to the folding area when the set is stitched. When the shuttle
moves to the folding area, the pick-up fingers loosen on the book. The shuttle is
operated by a 230V AC electric motor through a linear transmission.
3.4 The Stitch Head and Clincher
The single stitch head is a custom version of the Deluxe G8 stitch head. The
stitch head is installed vertically and upside down. The stitch-wire is fed from a
15kg (33-lb) spool in the stitch-wire cabinet. The stitch-wire spool can supply a
maximum of 291,500 stitches. The stitch head and clincher are aligned to the
centre reference line of the PSQ. The book is moved to each stitch position by
the shuttle.
The size of stitch or ‘wire draw’ setting is calculated from the set-thickness input
by the operator. Adjustment is made to the ‘wire draw’ by the PSQ. This
automatic adjustment makes sure the correct size of stitch is formed for every
thickness of book. The operator does not need to adjust the stitch head.
The clincher is held in a frame above the stitch head. The PSQ uses a clincher
with moving points. The clincher forms a high quality stitch that lies flat against
the book.
Drive for the stitch head and clincher operation is transferred from the main
motor by a system of chains, shafts and clutches.
The stitch head vertical-axis adjustment is made by a stepper motor. The set
thickness can also be automatically calculated from the thickness of the paper
and the number of sheets in a set. The stepper motor allows wire-draw and
stitch-head compression to change dynamically to match varying thickness jobs
without operator intervention.
3.5 The Stitch Process
The shuttle collects the set between the pick-up fingers and moves to the first
stitch position. When the book is stitched and moved to the next stitch-position,
the previous stitch moves across a stitch sensor. The stitch sensor detects the
steel of the stitch wire. If this sensor does not detect a stitch, a ‘missing stitch’
fault is indicated and production is stopped.
When the book is stitched correctly, the book is moved by the shuttle to the fold
position. If a book remains over the optical sensor next to the stitch head, a jam
is indicated and the PSQ is stopped.
If the stitch head jams, a stitch head jam sensor stops the machine. The stitch
head jam sensor is fitted next to the clincher cam and is connected to a PCB on
the stitcher PCB bracket.