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Programmable Weld Nut Sensors

TURCK 8/1/2018

Robust, Reliable Detection of Weld Nuts in Harsh Automotive Environments

TURCK's magnetic-inductive weld nut sensors provide efficient and economical detection of weld nuts in automotive applications. The sensors detect ferromagnetic components, such as nuts, bushings and spacer sleeves, to ensure these components are present before robotic welding occurs. These sensors are less complex than existing devices that require additional software or electronics to detect the target.

Weld nut sensors are programmed to differentiate between the nut and the sheet metal on which it is located, delivering accurate component detection. At the push of a button, the sensor “learns” the status of the weld nut/sheet metal combination (along with the status of the sheet metal alone). The TURCK weld nut sensor may be mechanically protected with a stainless steel sleeve (not included), which also acts as a guide to keep the weld nut in place.

Weld nut sensors are available in two versions offering different signal intensities and diameters to adapt to a wide variety of operating environments and material characteristics. The sensors also feature a rugged IP 67 rated housing that protects internal components from harsh welding zone conditions. Plus, the sensors offer temperature compensation to withstand the thermal changes common in welding environments.

• Rejection-free process for detecting weld nuts
• An economical alternative to more expensive optical or vision-based systems that often malfunction due to:
• Dirt and weld-splatter residue
• Frequently changing lighting conditions in welding zones
• Rugged construction delivers dependable performance
• Simple programming
• Bright LEDs indicate the output status

How TURCK Weld Nut Sensors Work

Programmable Weld Nut Sensors

1. Once the TURCK weld nut sensor has been programmed, it is mounted in sheet metal.  When a nut is not present, there is no output.  At this time, the green LED is illuminated.

Programmable Weld Nut Sensors

2. When a weld nut is present, it is detected by the sensor.  The sensor produces an output reflected by the  LED turning yellow.  At this time, the welding process initiates.

Programmable Weld Nut Sensors

3.  Welding begins.  The sensor's yellow LED remains illuminated until the weld nut is no longer present.

Programmable Weld Nut Sensors

Programmable Weld Nut Sensors

Note: Temperature Rating =  -25 to 70°C (-13 to 158°F).
 *  Sensitive area: Within this area the sensor signal changes when assembly parts are changed.
 **  Maximum area: The maximum signal intensity is reached if the sensitive area is completely covered.