1. Sensitive Drilling Machine
It is a small drilling machine is mounted on a bench in which feed is hand operated, and the
cutting force applied is determined by sense of feel of the operator. The parts of sensitive drilling
machine as shown below. It consists of a vertical column, a work table, head supporting the
motor and driving mechanism, and a vertical spindle for driving and rotating the drill.
The work is mounted on the work table which may be raised or lowered by the clamp to
accommodate work pieces of different sizes. The driving mechanism consists of V-belt drive
from machine spindle to drill spindle. Three or four speed stepped cone pulley is provided to
give various speed ranges. The spindle is designed and mounted in a sleeve such that the spindle
rotates and simultaneously moves up and down to provide feed for drill. This is achieved by a
rack and pinion mechanism.
2 Radial Drilling Machine
Radial drilling machines are used for drilling heavy work pieces, where it is easier to move the
drill rather than work and especially for the jobs where high degree of accuracy is required. It
consists of base, column, radial arm, drill head and driving mechanism. The arm of radial drilling
machine can be swing around the column to any position and angle. A wide range of spindle speeds, together with automatic feed of the spindle, makes the radial drilling machine suitable for
drilling large castings. For lowering or raising the radial arm, a separate motor is provided. The
work can be firmly champed on the table having T-slots. The table is fixed to the base. The radial
arm and the spindle can be adjusted without disturbing the work setting.
Kavungya answered the question on
March 6, 2019 at 12:36