Using Rexroth's non-contact Transfer units (NCT), the End Effector creates a dynamic lifting force using positive airflow (Bernoulli principle) to handle solar photovoltaic wafers without requiring a physical seal with their surface. This means that handling and transporting delicate solar wafers, a process previously achieved only by manual labor, can be automated.
The low pressure in the NCT provides a lifting force, similar to a vacuum suction cup. To prevent the wafer from contacting the End Effector, even if the wafer is warped, a complete vacuum seal is not desirable. Therefore, the NCT allows enough air to escape to create a gap between the wafer and the End Effector. Integrated edge guides (gripper flaps) align and constrain the wafer during transport for safe handling.
The End Effector can be integrated with SCARA, 6-axis, or Cartesian robots. A wafer presence sensor provides constant detection and feedback, allowing the robot to activate the End Effector when the wafer is detected.
The Non-Contact End Effector is available for standard 156 mm polycrystalline and multi-crystalline solar cells, and can reliably handle and transport wafers with 50-300 mum thickness, according to Rexroth.
See other Design News solar photovoltaic coverage: