Velvet Weaving Machine

Overview

A velvet weaving machine makes cut-pile velvet by the face-to-face method, weaving two separate base fabrics one above the other at the same time and joining them with a pile warp that passes back and forth between them. A knife runs down the middle and slices that pile warp, which splits the sandwich into two pieces of velvet, each with upright cut pile where the threads were severed. This double-plush method doubles output, since one loom makes two webs of velvet, and it gives a dense even pile that is hard to match by other routes. It is the standard way to weave upholstery velvet, velour, plush, and figured velvet for furnishing and apparel.

Three warps feed the loom. Two ground warps form the upper and lower base cloths, fed by the Ground Warp Let-off, and one pile warp weaves between them, fed by the Pile Warp Let-off. The Double-Shed Forming forming opens both sheds at once, the Dual Rapier Insertion inserts weft into each cloth, the Double Sley Beat-up beats both home, the Centre Cutting Knife knife splits the pile, and the Dual Cloth Take-up winds the two velvets separately. A Main Drive and Control System run the loom and its jacquard.

Weaving two cloths at once

The defining feature is that the loom forms two cloths in one set of motions. The Double-Shed Forming forming opens an upper shed and a lower shed simultaneously, separated by a fixed gap. The ground ends of each cloth are lifted by Ground Heald Frame frames to interlace their wefts into plain base fabrics. The pile warp is controlled separately and far more finely, because it must weave into the upper cloth on some picks and into the lower cloth on others, tying the two together with threads that span the gap. The size of that gap sets the pile height: a wider gap gives longer pile after cutting.

Jacquard control of the pile

What makes patterned velvet possible is that each pile end is controlled individually. The Jacquard Head head does this: a Hook Solenoid selects each Lifting Hook, a Griffe Knife knife lifts the selected hooks, and a Harness Cord runs from each hook down through a Comber Board to the heddle that lifts one pile end. By choosing on each pick which pile ends go into which cloth, the loom sets where pile appears and, with coloured pile warps, what colour it is. This is how figured velvet, where a pattern stands in pile against a flatter ground, is woven directly. A plain velvet uses the same head with a simple repeating selection.

Weft insertion and beat-up

Because two cloths are woven, the Dual Rapier Insertion insertion is doubled. An Upper Rapier inserts weft into the upper shed and a Lower Rapier into the lower shed on the same machine cycle, each fed by its own Weft Feeder drawing from an Accumulator Drum. The Double Sley Beat-up is also doubled: a Double Sley carries both an Upper Reed and a Lower Reed that beat each weft up to its own cloth fell, driven by the Beat-up Cam.

The cutting knife

After a length of double cloth is woven, the Centre Cutting Knife knife splits it. A thin Cutting Blade rides a Knife Carriage that traverses across the width on a Linear Guide Rail driven by a Servo Motor, slicing the pile warp threads that bridge the two cloths exactly midway. Each severed thread becomes two tufts, one standing up from the upper cloth and one from the lower, which is the cut pile. The blade must stay razor sharp so the tufts are cut clean and even, so a In-line Sharpener grinds it in line during running. A dull blade tears rather than cuts, leaving uneven pile and loose fibre.

Two take-up paths and the warps

After cutting, the two velvets part company. The Dual Cloth Take-up has two paths: the Upper Take-up Roller roller draws the upper velvet up and away and the Lower Take-up Roller draws the lower one down, each winding to its own Cloth Roll pile-out so the surface is not crushed. The Ground Warp Let-off feeds two ground warps from an Upper Ground Beam and a Lower Ground Beam at firm tension, while the Pile Warp Let-off feeds the pile warp, drawn from a Pile Warp Beam or a multi-colour Pile Bobbin Creel, at the steady tension the cut pile needs to stand evenly.

Drive, control, and use

The Main Drive turns the Main Shaft through a Clutch-Brake for pick-accurate stops, and the Control System runs the jacquard figure, times the knife traverse, and watches a Warp Stop-Motion for broken ends, all on an Microcontroller. The operator works at the Operator Panel. The loom weaves upholstery velvet and velour for furniture and automotive interiors, plush for toys and blankets, and figured velvet for apparel and furnishing, in cotton, viscose, polyester, and silk. Pile height, density, and figure are all set in the program, so a mill can move between plush furnishing velvet and fine fashion velvet on the same machine.