(under subclass 86.17) Grapples having means that is intended to release or rupture when excessive force is applied to the engaged grapple to permit disengagement from the grappled object.
SEE OR SEARCH CLASS
175, Boring or Penetrating the Earth,
301, for below ground impact means combined with releasable telescoping members having a frangible connection between the telescoping members.
285, Pipe Joints or Couplings,
1+, for pipe joints having means responsive to a predetermined force to release the means holding the joint together, and subclass 304 for pipe joints having means to hold the two pipe members together in assembled relationship but which will release upon the application of excessive forces.
