The present invention relates to industrial fasteners and more particularly to a one-quarter turn industrial fastener. 
Some types of industrial fasteners may be used to removably connect two panels; for example, the panels may be the enclosures of industrial equipment.  It may be desired to secure the two panels together so that they will not become loosened in ordinary usage and yet may be rapidly separated when necessary, for example, for repair or maintenance. 
When the two panels are of relatively rigid metal and it is desired that they be maintained in their joined relationship under considerable force of separation, special problems are presented.  For example, the two panels may be steel plates which may be subjected to separation forces as high as 1,000 pounds.  Many types of lightweight industrial fasteners would not be suitable under those conditions but would come apart and permit separation of the panels.  It is possible to join the panels by conventional bolts and nuts which would have to be unscrewed to permit separation of the two panels.  However, the separation of a bolt and its nut, particularly if they are tightened, may be a time-consuming task, may require many turns of either the bolt or the nut, and requires access to both sides of the panels. 
One type of one-quarter turn industrial fastener using a cam bolt structure is known from Ernest Schlueter's U.S. Pat.  No.  3,124,993, patented Mar. 17, 1962.  That device has found commercial acceptance and solves many of the problems presented by the need for rapid fastening and unfastening.  That device, however, is relatively complex, may be relatively expensive to manufacture, and requires the use of a separate tool for locking and unlocking.