Sectional Warping Machine

Overview

A sectional warping machine prepares the warp sheet for weaving when the fabric needs a coloured or striped pattern across its width. Instead of winding the full set of ends in one pass like a direct warper, it winds the warp in narrow bands called sections, building each section onto a large drum, then transfers the whole package onto a weaver beam in a second step. This two-stage method lets a weaver repeat a colour order across hundreds of ends without keeping a huge stock of beams in every colour, which is why it is the standard route for shirting, suiting, ginghams, and other patterned and short-run cloth.

The machine has two clear halves. The Yarn Creel holds the yarn cones and feeds the ends, while the Sectional Drum and the Reed Carriage build the sections. Once the full width is on the drum, the Beaming-Off Unit unit unwinds it onto the loom beam. A Drive and Gearing turns both the drum and the beam, a Tension and Stop-Motion system keeps the sheet even, and a Control System ties the steps together, all carried on a rigid Machine Frame.

The creel and yarn feed

The Yarn Creel is a long bank of stationary Cone Peg spindles, several hundred of them, each carrying a yarn cone. The yarn pulls off over the end of the cone so the cone never spins, which keeps tension steady at high speed. Every end passes through a ceramic Ceramic Yarn Guide and a Disc Tensioner that adds a small even drag, so that all ends reach the drum at the same tension and lie flat. A Broken-End Sensor watches each path and stops the machine the instant an end breaks or a cone empties, which prevents a missing end running into the beam. A Leasing Reed splits the sheet into a lease that preserves the exact order of the ends, the order that later sets the colour pattern in the cloth.

Building sections on the drum

The heart of the machine is the Sectional Drum, a wide cylinder turned by the drive. The Reed Carriage carries a fine Section Reed that spreads one band of ends to its exact width, perhaps 40 to 120 mm, and that band winds onto the Drum Shell. Because each new wrap sits slightly to one side, the section would slide off as a loose cone, so the Conical End Ring gives it a tapered wall to build against and the carriage steps sideways a fixed amount each turn to match. When one section reaches the planned length, measured by the Measuring Roller, the Reed Carriage indexes across on its Ball Screw and Linear Guide Rail, driven by a Servo Motor, and the next section is wound right beside it. Section by section the full warp width is built up across the drum.

Beaming off

With every section on the drum, the warp is complete but it is on the wrong package. The Beaming-Off Unit unit unwinds the whole sheet at once and winds it onto a Weaver Beam, the flanged beam the loom will use. A Pressure Roller bears on the building package so it winds hard and even, which matters because a soft or ridged beam sheds tension unevenly later on the loom. The beam turns in a pair of Beam Chuck cones, and the Drive and Gearing now drives the beam shaft instead of the drum, its Drive Clutch switching the torque from one to the other.

Drive, tension, and control

The Drive and Gearing uses a variable-speed Main Drive Motor through a Gearbox Housing and a pair of Helical Gear Pair reductions, with a Drum Brake that stops the drum fast when a sensor trips. Even tension is essential throughout: the Tension and Stop-Motion system floats a Dancer Roller on a sprung Tension Arm, and a Pressure Sensor reads the sheet tension so the drive can trim its speed to hold it constant. The Control System runs the program on an Microcontroller and a Bare PCB board, drives the motors through Relay contactors, and gives the operator a Operator Panel to enter the warp width, the length, and the section colour order. An Emergency Stop cuts everything at once.

Materials and construction

The Machine Frame is built from heavy cast Side Frame members tied by Cross Rail beams, because the drum and beam bearings must stay in precise alignment for the warp to wind square. Yarn-contact parts use hard wear surfaces: the guides are sintered alumina ceramic, the reed dents are polished steel, and the tensioner discs are chromed so they do not groove and fray the yarn. The drum shell is a true cylinder turned and ground so wraps lie flat. Bearings throughout are sealed Ball Bearing units kept clean of lint.

Use and variants

Sectional warping suits patterned, multi-colour, and short-run warps, where the saving is in not keeping many full beams in stock. It is slower per metre than a direct warper, which lays the whole width at once for plain single-colour warps in long runs, so a mill runs direct warpers for staple plain goods and sectional warpers for fancy and frequently changed patterns. Modern machines add automatic section measuring, servo traverse, and a length stop accurate to better than half a percent, so the warp ends exactly where planned. Width ranges from narrow shirting beams near 1.8 m to wide industrial and home-textile beams above 4 m, with the Yarn Creel sized to the end count the pattern needs.