Shearable fastener bolt and method for clamping electric wires, and electrical connector comprising a zero-protrusion shearable fastener

An electric connector, comprising:

• a wall surrounding a receptacle that receives a strand of an electric wire, the wall has a threaded hole extending through the wall and opening into the receptacle;
• and
• a fastener bolt screwed into the threaded hole and clamping the electric wire, the fastener bolt including:
• a bolt part having a head section, a thread section, and a shearing section connecting the head section and the thread section, the shearing section is adapted to break if a predetermined fastening torque is exceeded, the thread section is hollow and has a predetermined tensile breaking strength, the thread section has a breakage line along which the thread section is weakened, the breakage line extends slanted with respect to an external thread of the thread section and to an axial direction and extends helically in a direction opposite to a direction of the external thread, a pitch of the breakage line is larger than a pitch of the external thread;
• and
• a nut part screwed onto the thread section.

An electric connector, comprising:

• a wall surrounding a receptacle that receives a strand of an electric wire, the wall defining:
• a threaded hole extending through the wall and opening into the receptacle;
• a depression formed into the wall to a first depth in an axial direction of the threaded hole, the depression having a concave cross-section including a non-planar surface, the non-planar surface facing at least partially in the axial direction of the threaded hole away from the receptacle and at least partially in a radially inward direction relative to the axial direction;
• and
• a resting opening formed within the depression and into the wall in the axial direction from a bottom surface of the depression toward the receptacle to a second depth, distinct from the first depth, a bottom wall of the resting opening defining a planar resting area facing away from the receptacle, the depression surrounding the resting opening in a radially outward direction relative to the axial direction;
• and
• a fastener bolt screwed into the threaded hole and clamping the electric wire, the fastener bolt including:
• a bolt part having a head section, a thread section, and a shearing section connecting the head section and the thread section, the shearing section is configured to break if a predetermined fastening torque is exceeded, the thread section is hollow and has a predetermined tensile breaking strength;
• and
• a nut part screwed onto the thread section.