文档介绍：Constructure and Technology of Machine Tools
Keywords: Machine Tools ,Lathe,Bed, Headstock
Size, Bed and Tailstock of Engine lathe
SIZE
Lathe size is determined by swing and length, of the bed. The swing is twice the
distance from the live center point of the spindle to the top of the bed, or the largest
diameter that can be turned over the ways of a lathe. For example, a 10-in, lathe will
ruin a 10-in,-diameter workpiece over the ways, but not over the carriage cross-feed
slide. Sometimes two numbers are used to indicate swing, such as 17-12. The 17-in.
swing would be over the bed and the 12-in. swing over the cross slide.
The length of the bed includes the part the headstock rests on. It determines also
the distance between centers. A typical size might be a 3-foot bed with a distance of
23 in. between centers. Lathe beds are offered in many different lengths for each
available swing size.
A lathe should have a swing capacity and distance between centers that is at least
10 percent greater than needed to do any job that may be required. Standard lathes
come in a variety of designs and styles and may have a swing ranging from about 9 to
53 in. They are generally classified as small, medium swing, and heavy duty.
BED
The bed is the base or foundation of the lathe. It is a heavy, rigid casting made in
one piece. It is the "backbone" of the lathe and holds or supports all the other parts.
Located on the top of the bed is the way. More expensive lathes have bination
of V ways and flat ways. Less expensive lathes have flat ways only. Construction of
ways varies according to make. Some builders use ways made of hardened steel that
can he replaced if necessary. Others use flame-hardened ways that are an integral part
of the bed section.
The accuracy of the ways determines the performance that can be expected from
a lathe. Ways must be true and accurate So that the headstock, tailstock, and car