A dovetail joint is a joint similar to a bung , in which the shape of the bung (also: spring, prong or tenon) is remotely reminiscent of the forked shape of a swallow's tail . In contrast to a bung, the dovetail connection is more form-fitting , not only across the dovetail, but also in its longitudinal direction. The dovetail connection is joined in the third direction, which is also transverse to the dovetail.
A dovetail joint with multiple "jagged" dovetail joints is also referred to as a fir tree connection . This space-saving form is particularly common for fastening rotor blades of turbomachines . The high centrifugal forces are distributed over several contact surfaces in the connection.
Dovetail joints are used in many areas of technology, u. a .:
- Wood connection technology , especially because no additional metal connection elements (nails, screws ...) are required. It is used in particular to connect solid wood, for example in drawers, chests or musical instruments .
- Attachment of the blades on the impeller of a turbo machine .
Dovetail connections are also used in machine tools, with a trapezoidal groove (see picture below) incorporated in the machine table to accommodate clamping irons with a corresponding, negative trapezoidal shape, into which the clamping claws are inserted from the side and then connected to the workpiece by clamping .
After nearly identical principle called work dovetail guides , with the difference that not going to rigid, non-positive connection, but on a positive, the Translation permitting sliding emphasis. This type of dovetail guide can also be implemented as a roller guide through a special arrangement of needle cage rail guides .