Main parts of a loom is given below:
1. Heald Shaft
This part is related to the shedding mechanism. The heald
shaft is made of wood or metal such as aluminium. It carries a number of heald
wires through which the ends of the warp sheet pass. The heald shafts are also
known as ‘heald frames’ or ‘heald staves’. The number of heald shafts depends
on the warp repeat of the weave. It is decided by the drafting plan of a weave.
The main function of the heald shaft is as follows:
It helps in shed formation
It is useful in identifying broken warp threads
It maintains the order or sequence of the warp threads
It determines the order of lifting or lowering the required
number of healds for a pick. In other words it helps in forming the design or
pattern in a fabric.
It determines the warp thread density in a fabric, i.e. the
numbers of heald wires per inch determine the warp thread density per inch.
2. Sley or lay
It is made of wood and consists of the sley race or race
board, reed cap and metal swords carried at either ends. The sley mechanism
swings to and fro. It is responsible for pushing the last pick of weft to the
fell of the cloth by means of the beat up motion. The sley moves faster when
moving towards the fell of the cloth and moves slower when moving backwards.
This unequal movement is known as ‘eccentricity of the sley’. It is needed in
order to perform the beat up and also to give sufficient time for passage of
shuttle to pass through the warp shed. The beat up of the lastly laid pick of
weft is accomplished through a metal reed attached to the sley.
3. Shuttle
It is basically a weft carrier and helps in interlacement of
the weft with the warp threads to form cloth. The shuttle which is made of wood
passes from one end of the loom to the other. It travels along the wooden sley
race and passes between the top and bottom layers of the warp sheet. The
shuttle enters a shuttle box fitted at either ends of the loom, after passing
through the warp shed. A shuttle normally weighs about 0.45 kgs.
4. Shuttle Box
It is the housing for the shuttle and is made of wood. It
has a spindle and a picker. It may also accommodate the picker without spindle.
The top and side of the box towards the sley race are open. The shuttle dwells
inside the box for the intermediate period between two successive picks.
5. Picker
The picker is a piece made either of leather or synthetic
material. It may be placed on a spindle or grooves in the shuttle box. It is
used to drive the shuttle from one box to another. It also sustains the force
of the shuttle while entering the box.
6. Reed
It is a metallic comb that is fixed to the sley with a reed
cap. The reed is made of a number of wires and the gap between wires is known
as dents. Each dent can accommodate one, two or more warp ends. The count of
the reed is decided by the number of dents in two inches. The reed performs a
number of functions which are enumerated as follows:
It pushes the lastly laid pick of weft to the cloth fell
It helps to maintain the position of the warp threads
It acts as a guide to the shuttle which passes from one end
of the loom to the other.
It determines the fineness of the cloth in conjunction with
the healds.
It determines the openness or closeness of the fabric.
There are various types of reed such as ordinary reed, gauze
reed, expanding reed, V reed etc.
7. Warp Beam
This is also known as the weaver’s beam. It is fixed at the
back of the loom. The warp sheet is wound on to this beam. The length of warp
in the beam may be more than a thousand metres.
8. Back Beam
This is also known as the back rest. It is placed above the
weaver’s beam. It may be of the fixed or floating type. In the first case the
back rest merely acts as a guide to the warp sheet coming from the weaver’s
beam. In the second case it acts both as a guide and as a sensor for sensing
the warp tension.
9. Breast Beam
It is also known as the front rest. It is placed above the
cloth roller at the front of the loom and acts as a guide for the cloth being
wound on to the cloth roller. The front rest together with the back rest helps
to keep the warp yarn and cloth in horizontal position and also maintain proper
tension to facilitate weaving.
10. Cloth Beam
It is also known as the cloth roller. The woven cloth is
wound on to this roller. This roller is placed below the front rest. It is also
known as the cloth roller. The woven cloth is wound on to this roller. This
roller is placed below the front rest.
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