Cap, cap mold, securing structure part using cap, and method for mounting cap

A securing structure part which includes a fastener which passes through a through-hole formed in overlapping multiple structure elements of an aircraft, a collar which is fastened to a tip part of the fastener protruding from the surface of the structure elements, and a cap which is mounted to surround the tip part of the fastener and the collar, and which secures the structure elements using the fastener and the collar,

• wherein the cap is mounted in a non-engaged state with respect to the tip part of the fastener and the collar,
• wherein a filler engaging part is formed on the inner peripheral surface of the cap, and the filler engaging part has a female threaded helical shape which turns about the center axis of the cap, and engages with a filler which fills a space formed between the inner peripheral surface, and the fastener, the collar, and the surface of the structure element and is cured, and
• wherein the filler engaging part includes:
• a first helical engagement part which is formed in a region near a cap inner part of the inner peripheral surface in the center axis direction;
• and
• a second helical engagement part which is formed in a region near a cap opening-end part of the inner peripheral surface in the center axis direction, has a greater inner diameter than that of the first helical engagement part, and has a helical direction which is opposite to that of the first helical engagement part.

A securing structure part which includes a fastener which passes through a through-hole formed in overlapping multiple structure elements of an aircraft, a collar which is fastened to a tip part of the fastener protruding from the surface of the structure elements, and a cap which is mounted to surround the tip part of the fastener and the collar, and which secures the structure elements using the fastener and the collar,

• wherein the cap includes:
• a cap engagement washer which is interposed between the surface of the structure elements and the collar, and has a periphery in which a male threaded helical engagement part is provided;
• and
• a cap body which is mounted in a non-engaged state with respect to the tip part of the fastener and the collar, and has a female threaded helical engagement part which is formed on the inner peripheral surface near an opening-end part of the cap body and engages with the male helical engagement part of the cap engagement washer.

A method for mounting a fastener which passes through a through-hole formed in overlapping multiple structure elements of an aircraft, a collar which is fastened to a tip part of the fastener protruding from the surface of the structure elements, and a cap which is mounted to surround the tip part of the fastener and the collar and in which a portion between the tip part of the fastener and the collar is filled with a filler, comprising:

• a masking member mounting step of mounting a masking member for masking an outer peripheral surface of the cap;
• a filler filling step of filling the inside of the cap with the filler;
• a cap mounting step of mounting the cap on the tip part of the fastener and the collar;
• and
• a masking member removal step of removing the masking member from the cap.