Instrumentation Monthly Test | Measurement | Control
Cotton spinning machines use a robotic vacuum cleaning system to prevent lint build-up on machinery and product. To ensure the vacuum cleaning robot does not collide with the spinning machine, a Contrinex Background Suppression photoelectric sensor detects their presence.
Customer Application
Lint is generated from the process of spinning cotton and if lint is allowed to accumulate, it will eventually clog the small eyelets and guides on the spinning machine.
Because a build-up of lint can cause yarn breakage, spinning machinery is equipped with vacuum systems that constantly rove the machine to collect lint. These systems depend on a relatively slow-moving vacuum head, which travels on a rail-mounted above.
The spinning machines are tended by operators who might accidentally leave items in the path of the vacuum head. To prevent collisions with these objects, the existing detection system on the vacuum head consists of a limit switch with a mechanical wand attachment. As soon as the wand touched an obstacle, it caused the vacuum head to reverse its direction of travel, but the customer wanted to upgrade to a non-contact detection solution more suited to an automated environment.
Customer Solution
Contrinex’s LHR-C23PA cubic and LHR-M18PA background suppression photoelectric sensors, available from PLUS Automation, are ideal for this application.
Despite their small size (20 x 30 x 10mm or Ø18 x 37mm), these sensors are both robust and high-performance offering a sensing range of 300 or 250mm respectively.
The sensor’s precise background suppression enables them to detect the presence of any obstacle regardless of colour, brightness or angle in relation to the position of the sensor on the vacuum head.
An LHR-C23PA cubic sensor is mounted on the vacuum head to provide sensing for the robotic system’s safety reversal function. The operating range can be adjusted to detect an obstacle between 15 to 250 mm away, whilst ignoring the machine, in which case the cleaning machine simply reverses its direction of travel, without interrupting the cleaning function.
The C23PA family of sensors also benefits from having a range of complementary low-cost stainless-steel mounting and protection bracketry options.
