Sealing structure

A sealing structure comprising:

• a predetermined member including an opening part;
• and
• a sealing member for sealing the opening part of the predetermined member, wherein the sealing member includes:
• a main body;
• a thread part fixed to the main body, wherein if the main body is rotated in a normal rotation direction, the thread part is screwed into the opening part of the predetermined member;
• and
• an elastically deformable arm part joined to the main body at one end thereof,
• wherein a convex part is formed in one of the predetermined member and the arm part and a concave part is formed in another of the predetermined member and the arm part,
• if the main body is rotated in the normal rotation direction, the arm part is elastically deformed while a part of the arm part slides on a surface of the predetermined member until the main body is rotated to a predetermined rotational position and, when the main body is rotated to the predetermined rotational position, the convex part fits in the concave part and the elastic deformation of the arm part is released, whereby the rotation of the main body from the predetermined rotational position is prevented,
• if the main body is rotated to a reverse rotation direction from the predetermined rotational position, the convex part slides on and climbs over a wall part of the concave part while the arm part is elastically deformed, whereby the prevention of the rotation of the main body from the predetermined rotational position is released,
• wherein the convex part or the concave part is formed such that, when the main body is being rotated in the reverse rotation direction and the convex part is sliding on the wall part, an angle A formed by a direction of force applied to the arm part from the predetermined member and a straight line connecting a contact part of the convex part and the wall part and a rotation center of the main body is smaller than 90 degrees when viewed in a rotation center direction of the main body, and
• wherein the concave part includes a first inclined wall part and a second inclined wall part, the first inclined wall part disposed further in the reverse rotation direction than the second inclined wall part, wherein the second inclined wall part extends on a straight line that passes through the rotation center, and the first inclined wall part is inclined relative to the straight line and extends towards the straight line in a radially outer direction such that a radially outer side of the first inclined wall part is disposed further in the normal rotation direction than a radially inner side of the first inclined wall part.

A sealing structure comprising:

• a predetermined member including an opening part;
• and
• a sealing member for sealing the opening part of the predetermined member, wherein the sealing member includes:
• a main body;
• a thread part fixed to the main body, wherein if the main body is rotated in a normal rotation direction, the thread part is screwed into the opening part of the predetermined member;
• and
• an elastically deformable arm part joined to the main body at one end thereof,
• wherein a convex part is formed in one of the predetermined member and the arm part and a concave part is formed in another of the predetermined member and the arm part,
• if the main body is rotated in the normal rotation direction, the arm part is elastically deformed while a part of the arm part slides on a surface of the predetermined member until the main body is rotated to a predetermined rotational position and, when the main body is rotated to the predetermined rotational position, the convex part fits in the concave part and the elastic deformation of the arm part is released, whereby the rotation of the main body from the predetermined rotational position is prevented,
• if the main body is rotated to a reverse rotation direction from the predetermined rotational position, the convex part slides on and climbs over a wall part of the concave part while the arm part is elastically deformed, whereby the prevention of the rotation of the main body from the predetermined rotational position is released,
• wherein the convex part is provided on the arm part and has a first inclined part and a second inclined part, the first inclined part disposed further in the reverse rotation direction than the second inclined part, wherein an inclination of the first inclined part extends from a first axial side of the arm part facing towards the predetermined member to a second axial side of the arm part facing away from the predetermined member.