Joint structure

A joint structure comprising:

• an upper block arranged on a lower block having a fluid passage, in which a first pin insertion slit, a first sleeve insertion hole, and a first bolt insertion hole are formed, and the first sleeve insertion hole is located between the first pin insertion slit and the first bolt insertion hole;
• an auxiliary member provided on an upper surface of the upper block, in which a second pin insertion slit, a second sleeve insertion hole, and a second bolt insertion hole are formed, and the second sleeve insertion hole is located between the second pin insertion slit and the second bolt insertion hole;
• a sleeve inserted into the first sleeve insertion hole of the upper block and the second sleeve insertion hole of the auxiliary member, an inside of which serves as a fluid passage communicating with the fluid passage of the lower block;
• a pin having a first head, a first shaft portion, and a first male threaded portion, the first head abutting against an upper surface of the auxiliary member, the first shaft portion being inserted into the first pin insertion slit and the second pin insertion slit, and the first male threaded portion being screwed into the lower block;
• and
• a bolt having a second head, a second shaft portion, and a second male threaded portion, the second head abutting against the upper surface of the auxiliary member, the second shaft portion being inserted into the first bolt insertion hole and the second bolt insertion hole, and the second male threaded portion being screwed into the lower block, wherein
• the first pin insertion slit opens to one side surface of the upper block in a longitudinal direction,
• the second pin insertion slit opens to one side surface of the auxiliary member in the longitudinal direction, and
• a lower surface of the auxiliary member is formed by a pair of inclined surfaces that gradually extends away from the upper surface of the auxiliary member from two ends of the auxiliary member in the longitudinal direction toward a center.