Clamping apparatus

摘要

In a clamping apparatus, a pressing member is moved on a base in a vertical and horizontal directions by rotation of a bolt. The bolt is provided with a longitudinal hole open end of which is covered by a window. A rod is placed in the hole so as to fix the inner end thereof to the inner end of the hole. A transparent holding member holding a colored fluid is sandwiched by the open side end of the rod and the window. When a tension stress is developed in the bolt, the open side end is far away from the holding member so that fluid covers the open side end.