FROM
THE BEGINNING TO THE PRESENT DAY
More than 40 years of progress
FROM THE MECHANISATION OF HAND-OPERATED MACHINES RIGHT UP TO MACHINES WITH FULL ELECTRONIC PROGRAMMING through pasteboard card control. After having alleviated the very heavy manual work of the operators of hand machines, by converting them to motor drives and then producing these machines right up to the early fifties, we produced the first automatic flat knitting machine: the P457, in its two versions, B and T4. Characterised by a chain-controlled mechanical movement, this machine represented just the first step on an increasingly more sophisticated technological path. Only a short time elapsed before the development of the first automatic machines with pasteboard card control, which featured an ever-increasing number of functions and commands that were operative for the full traverse of the carriage. Among these were the PT4, (which was also available as the PT-tr, with stitch transfer on both beds and as the PT4dc, a double-system version), the PFS, (which introduced jacks selection and was available in double-system as the PFSdc), the PRT, (available in double-system as the PRTdc and in the coarse gauges 2, 2½ and 3 as the PRT6), the PET4 and PERT series, (on which, for the first time, pasteboard card control gave way to a system of electronic programming) and the famous P80, which, in its PE80 version, featured an electronic programming unit.
INDIVIDUAL NEEDLE SELECTION
the PAJ and PDE series with electronic programming
A
first step on the path to achieving "needle by needle" selection
was the development of the PAJ machine, which introduced individual needle
jacquard selection, achieved by the use of steel cards mounted on either
one or two rotating prisms, located underneath the needlebeds, which activated
each needle via long selecting platines protruding from the beds. Then,
in 1970, one of the most important patents in Protti's history was taken
out: this dealt with the "needle by needle" electronic control
system (Patent No. 900921 of 25/07/70: "Electronic/mechanical apparatus
for the selection of the needles in a flat knitting machine, in order
to achieve the knitting of jacquard fabrics"), which put the company
right at the forefront of technological achievement in the knitting machine
sector and led to the development of a new and revolutionary range of
machines: the PDE series.
THE
OTHER FULL JACQUARD MACHINES
the P90 and P94 series and the evolving programming systems In
effect, the P90 series represented the first generation of machines
that was completely computer controlled and it was therefore truly revolutionary
in its structural technology, while still retaining the knitting characteristics
that had been derived in part from the machines of the PDE series. The
double-system P90 had a needlebed width of 230 cm and was equipped with
special needles for stitch transfer and narrowing; with single-butt
platines and with auxiliary platines for individual needle selection.
The P90S version was fitted with a stitch presser device (DSP), for
the production of shaped pieces and the knitting of special stitch effects.
In its P90G variant, the machine was provided with a set of special
intarsia yarnfeeders. All machines in the P90 range were available in
the coarse gauges of 2, 2½, 3, 3½ and 4, and from 5 to
12 gauge. The four-system version was the P94, which had features identical
to those of the P90, (except for the number of systems and the provision
of two carriages). All the full-jacquard machines were equipped with
an electronic programming unit, with a 512 Kb memory and 5¼"
floppy disks. Connected directly to the machine, this allowed programming
to be carried out even when the machine was running. On request, a separate
programming unit was available, the PTV90, to allow patterns and fabrics
to be prepared away from the machine: this consisted of a minicomputer,
keyboard, graphics tablet, floppy disk drive and printer.
The
PT11, with 203 cm beds, was a single-system machine with high- and low-butt
needles, built in gauges from 5 to 18, without stitch transfer. The
PT21 offered the possibility of double transfer from either high- or
low-butt needles, or both, and the PT22 was also built as a double-system.
From these two models, we moved quite quickly to the current ones: the
PT222 (and, before that, the PT221) and the semi-jacquards PT241 and
PT242. These are very reliable, efficient and high-producing machines,
based on a technology that is supported by 40 years of experience and
continual development, to offer the best results at all times. This is a series of electronically programmed machines for the production of ribs and cuffs and their automatic loading onto the magazine bars of the Cotton frame. The loading of these ribs and cuffs directly onto the magazine bars, in predetermined numbers and in the exact position required, offers, on the one hand, precise and accurate running-on and significant savings in the costs of labour, of yarn and of intermediate magazine bars and, on the other, very high production rates, due to the variable carriage stroke, which adapts itself to the width of the piece to be produced. Later versions included the P200, (which had the advantage of being able to automatically exchange the full magazine bar for an empty one, without interrupting production and which was also produced in the P200 2- version for the simultaneous production of two cuffs and, as the P200 2D, with doublings), the P300 and the P400, (in its two versions: P401 being the standard model and P401D the one with doublings), all
leading up to the current model, the P500, in its 4 versions: P500,
the standard version, with high and low butt needle selection, used
principally for the production of ribs, cuffs and trims, which are automatically
loaded onto the magazine bars of Cotton frames or linking machines;
P500S, the version that enables selections to be made on four auxiliary
platines, located on the needlebed, thereby giving the capability of
producing a large number of pattern effects, (cables, lace, small jacquards),
to enhance and embellish the finished garment; P500D, the standard version
with a doubling device that enables stitches to be doubled at intervals,
thus making ribs more elastic and, at the same time, eliminating any
creasing; P500SD, which is provided with both the auxiliary platines
and the doubling device. |