An ejector pin is a very essential accessory while using annular cutters. Ejector pins are called Pilot Pins.
Ejector pins have the following three important functions:
- Centring: The ejector pin is exactly positioned to the centre punch mark. Switch the magnet on and the machine and tool are in the drilling position.
- Oiling: By means of the automatic internal lubrication, cutting oil is supplied via the ejector pin to the bit in just the right quantity.
- Ejecting: In the final stage, the ejector pin, pre-stressed by means of a spring, pushes the core out of the drill hole.
Ejector pins need to be selected as per the cutting length and diameter of the cutters. Every cutting length needs a different type of ejector pin. Generally 30, 55, 75 & 110 mm are the cutting lengths of annular cutters. Also, annular cutters from 12-60 mm diameter need thinner ejector pins while annular cutters from 61-150 mm need thicker ejector pins.
Here are different types of pilot pins or ejector pins.