Dust cap

A dust cap to be mounted to a receptacle of a bayonet locking connector when a plug is not connected to the receptacle, the dust cap comprising:

• a housing comprising:
• an insertion part, at a front end thereof, to be inserted into a shell of the receptacle, with rotation thereof in the circumferential direction of the shell being restricted,
• a lid part at a back end thereof, and
• a cantilever beam between the insertion part and the lid part, the cantilever beam extending in a direction intersecting with the insertion direction in which the insertion part is inserted;
• and
• a coupling comprising:
• a cylindrical inner circumferential surface, and
• a protrusion for bayonet locking on the inner circumferential surface at a front end of the coupling,
• the coupling being mounted around the housing so as to be capable of rotating relative to the housing and a back end of the coupling being closed by the lid part;
• a tip portion of the cantilever beam being located within a groove formed on the inner circumferential surface of the coupling;
• the cantilever beam being not bent in a locking state in which the protrusion is fitted into a depression for bayonet locking, formed on an outer circumferential surface of the shell;
• and
• when the coupling is rotated relative to the housing in order to release the locking state, the tip portion of the cantilever beam being pushed by an inner wall of the groove to bend the cantilever beam.