180 Agricultural Mechanics and Technology Systems Copyright Goodheart-Willcox Co., Inc.
Early
power tools were developed to perform the tasks of hand tools
with increased effi ciency and less manual effort. The fi rst power sources
were wheels driven by running water, wind, or harnessed livestock. Power
tools driven by natural sources were large tools permanently installed and
restricted to the geographic location of the power supply. For example,
sawmills were located on creeks with reliable fl owing water. The advent of
steam power allowed shops that used power tools to be located closer to
sources of raw materials or to methods of transportation used for commerce.
History credits the invention of the fi rst handheld power tool to the
German engineering fi rm C&E Fein when they introduced their electric
drill in 1895. It was a cumbersome and ineffi cient tool, but it paved the way
for the development of modern power tools.
Classifi cation of Power Tools
Like hand tools, the name of a power tool usually refl ects its intended
use or its method of operation. Sometimes the tool inventor’s name or
developing company becomes the common name of the tool. Often, tools
used in different areas of the country have different names. It is important
that you attempt to use the proper or offi cial names of tools when
communicating with others to avoid confusion.
Power tools can be classifi ed by power source, size or portability, or the
type of work they are built to do. Professionals in different occupations use
different collections of tools. For example, carpenters use tools designed for
woodworking, and machinists use tools built for metalworking. Mechanics
use an entirely different set of tools for their jobs. Many power tools are
versatile enough to perform multiple tasks and may be better classifi ed by
the type of job they do. Drills, for example, may be used by woodworkers,
metalworkers, and mechanics, as well as by plumbers, electricians, and many
others. Knowing how tools are classifi ed
can help you select the best tools for
performing different tasks.
Bigger stationary tools are often more
powerful than their smaller, portable
counterparts. Mounting a stationary tool
to the fl oor or to a secure workbench
strengthens its stability. This reduces safety
risks and lets the user perform repeated
tasks with precision and consistency.
All early power tools were stationary
and were driven by natural sources or, later,
by bulky steam or internal combustion
engines. See Figure 8-1. The cost of early
engines and electric motors was so high
that it was much more economical to use a
single power source to operate many tools.
Delmas Lehman/Shutterstock.com
Figure 8-1. Steam power was used in the past to generate power
for agricultural equipment.