During the operation of the water jet loom, the rotatio […]
During the operation of the water jet loom, the rotation of the water pump cam causes the pump cam lever to pull the plunger to move to the left, so that the water pump sucks water from the pontoon box, and the water is received and then sprayed from the nozzle. At the same time, the yarn presser is opened to release the weft yarn, which is driven by the water flow, and is guided from one side of the fabric to the other side, because after the end, the yarn presser is closed and clamps the weft yarn until the next weft insertion.
When the water jet loom stops, step on the weft insertion pedal, the pump rod pushes the pump cam rod, pulls the water pump plunger, the pontoon box absorbs water, releases the pedal, and the nozzle sprays water to complete a weft insertion.
(1) The structure of the water pump
The water pump is the most important device in the weft insertion mechanism.
When the cam turns from a small radius to a large radius, the coupling rod moves to the left under the drive of the pump cam rod, so that the water pump spring is compressed and a negative pressure is formed inside the water pump. The inlet check valve opens, and the outlet check valve closes. The water pump is sucked from the pontoon box. When the cam suddenly drops from the maximum radius to the minimum radius, the action of the water pump spring makes the plunger of the water pump move to the right and the pressure directly acts on the water column in the suction water pump. At this time, the inlet check valve is closed and the outlet check valve is closed. When it is turned on, the water is forced out from the water pump, and then sprayed out through the nozzle of the outlet pipe.
(2) Water pump valve
The water pump valve is integrated with the water pump body. The inlet one-way valve is connected with the water inlet pipe, and the outlet one-way valve is connected with the water outlet pipe. These joints must be tightly connected, not leaking water or air, otherwise, when the water jet loom is running, the pump valve ball will move irregularly, and the water volume will be unstable, causing short weft defects.
(3) Pump stroke
The amount of water sprayed from the nozzle depends on the stroke of the pump and the diameter of the plunger. The commonly used stroke range is 10mm-12mm. The larger the pump cam moves, the more water will be discharged by the pump. The plunger diameters are 16mm, 18mm, 20mm, 22mm, 24mm, 26mm, 28mm, etc. On a wide loom, a diameter of 30mm is used to ensure enough water to guide the weft smoothly to the end.
(4) Water pump pressure
The pressure of the water pump mainly depends on the diameter and K value of the water pump spring and plunger. The diameter of the water pump spring and plunger is determined according to the type of raw material, the width, and the number of revolutions of the loom. At present, the commonly used water pump springs on water jet looms have four steel wire diameters: 8.5mm, 9mm, 9.5mm, and 10mm, and plunger diameters are 18mm, 20mm, 22mm, 24mm, etc. On the newly developed water jet loom with a width of 3.5 meters, the plunger diameter has reached 40mm. The value of k is set by the rotating spring back cap according to the flight condition of the weft when the loom is actually running. The pressure of the water pump is closely related to the K value, the diameter of the plunger, and the spring of the water pump.