The Parallel Counter-marche System
In a counter march loom, every harness is actively involved in each shed: each harness is either lifted or pulled down by each pedal.
The diagram helps you to understand how the Louët parallel counter march system works.
Each harness and corresponding lams are attached to the cord, running over the six rollers.
The ends of the cord are connected, so the cord is a closed circuit.
- When treadle A is pressed down, lam C moves the outside cord downwards.
- The inside cord moves in the opposite direction and pulls harness F upwards, as indicated by the arrows.
- When B is treadled down, lam D pulls the inside cord and also the harness downwards.
- In their action, the lams and the harnesses always stay horizontal. This means that all treadles work the same over the full width of the loom.
Uneven sheds, for example a satin weave shed, where four harnesses are lifted and one is pulled down, open cleanly every time. The warp ends on the fifth harness do not tend to ride up as they often do with jack looms. When the shed is made, the same tension is applied to the raised ends as to the lower ones resulting in equal tension everywhere on the warp.
Advantages of this system:
- is very light to treadle, each treadle requires a similar effort no matter what its position across the loom
- there is no clashing of lams as the lams are parallel to the shaft bars, and extend across the width of the loom.
- The lams remain hoizontal during their movement- this means the entire width of the loom can be used for treadles- so even for the 90cm loom, 14 treadles are available for the 12 shaft loom
- the horizontal lam movement, and the cords running over pulleys at the top of the loom also allows for a a compact loom construction- a low line loom, that doesn't require extra height for pivoting jacks and pivoting lams
- there are no tie-ups in the middle of the lower shaft bar, so you can move the heddles freely across the shafts.
- there are no cords connect lams to jacks running through the middle of the warp