PCB Handling with Internal Hole Gripping: A Soft Gripper Solution

Handling PCBs automatically can become tricky when the available gripping space is extremely limited.For this application, the PCB needs to be handled gently, but the gap between the workpieces in the tray is too narrow for a conventional soft gripper to approach from the outside.Instead of trying to squeeze the fingers into the gap, we used a different approach: gripping the PCB from an internal hole.

The Challenge: Limited Space Around the PCB

The PCB needs to be picked from a tray and transferred during the automated process.The main issue is the limited space around the workpiece. The tray spacing is too narrow for the gripper fingers to move down between the PCBs and establish a stable external grip.At the same time, the PCB needs to be handled carefully to avoid unnecessary contact with components or leaving marks on the board.So the gripping method needed to solve two problems at once:

• Very limited space around the PCB
• Gentle and stable handling

The Solution: Internal Gripping Through an 11 mm Hole

Rather than approaching the PCB from its outer edges, we designed the soft gripper to work with an existing hole in the board.The hole has an inner diameter of 11 mm.The gripping module enters the hole and expands to create an internal supporting force. This allows the PCB to be picked up without requiring extra space around its outer edges.This approach is particularly useful when the PCB is tightly packed in a tray and there simply isn't enough room for the fingers to come down from the side.

Why Use Internal Support?

For PCBs with suitable holes, internal gripping can provide a practical alternative to edge gripping.The gripper does not need to find a large external gripping area. Instead, it uses the available internal structure of the PCB itself.This can help with:

• Narrow tray spacing – no need to insert fingers between tightly arranged PCBs.
• Flexible gripping – the soft gripping structure adapts to the workpiece during contact.
• Reduced edge contact – the gripping point is moved away from the PCB's outer edge.
• More stable handling – internal support helps keep the PCB in position during transfer.

A Different Way to Grip a PCB

Not every PCB handling problem can be solved by simply making the fingers smaller.Sometimes, the better question is:Where else can we grip the workpiece?In this case, the answer was an 11 mm internal hole.By changing the gripping direction from external clamping to internal support, the soft gripper can work in a space where conventional downward gripping is difficult.For PCB automation, details such as hole diameter, tray spacing, board geometry, component layout, and required gripping force all matter when selecting the right gripping method.If your PCB is tightly arranged in a tray and there is not enough space for conventional gripping, an internal-hole gripping solution may be worth considering.