Handling hosiery easier

The loading of the legs of tights onto a line closing machine has proved difficult to automate. Now, Detexomat claims to have solved the problem

Making tights is not an easy job. While some stages of manufacturing have been fully automated, the initial loading of the line closing machinery with basic knitted nylon tubes that form the legs of tights has proved a difficult challenge to automate.

The problem arises because the nylon tubes come off the manufacturing line in a jumbled heap and must be manually selected by an operator who must present them to the automated sewing machine correctly oriented: the toe at one end and the welt, or body section, at the other.

Now, however, this laborious process of selecting and orienting the nylon tubes prior to sewing has been eliminated, thanks to a new machine designed by Mick Hodges and his team at Detexomat machinery.

The machine itself contains a large bowl feeder into which the tubes are delivered in a completely random fashion. An INA carriage is used to carry a suction based picker that descends into the bowl. Once the picker nears its target, a photocell detects the white colour of the nylon and activates a suction probe. With a leg tube or tubes held by the suction, the arm of the picker withdraws. The actuator itself moves upwards inside a tube through which air is blasted downwards. This ensures that the picker arm is carrying one tube only; any other tube that may be intertwined with it will be blown back into the feeder bowl by the air.

When the actuator reaches a predefined spot, the nylon tube is released and transported through a pipe by suction to a dispenser unit. Once carried the correct distance into the dispenser, its presence is detected by a photocell and a latch mechanism on the end of the dispenser moves to hold the nylon tube in place. Once latched, suction is cut off and then reversed to blow the nylon tube straight within the dispenser. The air is then cut off and the latch releases the hose onto a conveyor.

The conveyor moves the hose through the machine until it reaches a predefined position where it is detected by yet another photocell that activates a second picker unit that carries the toe or the welt end of the garment into an orientator unit.

There are two photocells in the orientator unit. If the garment is presented to the unit toe first, both the photocells trigger and the garment will be sucked through the small orifice. It travels though the unit until it reaches another gate that closes, trapping the hose.

If a welt is presented to the unit, however, the first photocell triggers but not the second, since the garment cannot not pass welt first through the orifice. In this case, forward suction is then cut off and vertical suction applied. The welt then travels upwards where it is trapped by another gate. The forward suction is then reapplied, drawing the hose back into the pipe allowing it to be presented toe first to the next stage.

Once at the turret end of the machine, the hose is correctly oriented for the next stage of the process which involves opening the welt end of the hose for presentation to another machine that sews the two welts together.

This is achieved by the use of two grippers that open the welt to a box. Once the grippers have opened the welt end, the machine indexes around to another section where two fingers move into the opened welt. The unit uses two sets of such fingers on the machine. Once both have been loaded, the two leg parts of the garment are ready to be automatically presented to a line closing machine that can sew them both together forming the garment.

{{DetexomatTel: High Wycombe (01494) 521861Enter 420}}