A holding fixture for a workpiece 37.5 mm thick at the clamp locations is being designed. The detail of one of the clamps is shown in the figure. A spring is required to drive the clamp upward when removing the workpiece with a starting force of 45 N. The clamp screw has an M10 × 1.25 thread. Allow a diametral clearance of 1.25 mm between it and the uncompressed spring. It is further specified that the free length of the spring should be L0 ‰¤ 48 mm, the solid height Ls ‰¤ 31.5 mm, and the safety factor when closed solid should be ns ‰¥ 1.2. Starting with d = 2 mm, design a suitable helical coil compression spring for this fixture.

Wire diameters are available in 0.2-mm increments between 0.2 to 3.2mm.

Transcribed Image Text:

Clamp screw Spherical washer Clamp Slot Groove Workpiece Pin 보 .