The sensitive drilling machine

The main elements of a typical sensitive drilling machine are shown in Fig. 8.1. 

Base - provides a solid foundation for the machine, into which the pillar is securely clamped. 

Pillar - provides a solid support for the drill head and worktable. 

Worktable - provides a flat surface in correct alignment with the drill spindle upon which the workpiece can be positioned. Tee slots are provided for clamping purposes. The worktable can be raised, lowered and swung about the pillar and be securely clamped in the required position. 

Motor - provides the drive to the spindle through a five-step pulley system and a two-speed gearbox. Fig. 8.2. Thus five pulley speeds with A and B in mesh and five with C and D in mesh give a range of 10 spindle speeds from 80 to 4000rev/min. 

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