Joint device for joining pretensioned brace member to connector nodes in space truss structure

A joint device for joining a pretensioned brace member to connector nodes on the diagonal line of a grid formed in a space truss structure assembled by using structural members, comprising:

• a brace member having a steel rod providing a swelled portion formed at one end thereof and a threaded connector portion formed on the outer surface of another end thereof, a first joint member for connecting said one end of the steel rod to one connector node, and a second joint member for connecting said another end of the steel rod to another connector node, said first joint member being a first sleeve providing a longitudinal hole formed therein for inserting said steel rod, an end face of which contacts a back surface of said swelled portion so as not to fall off from said steel rod, and a first connecting adapter for joining said first sleeve to one connector node,
• said second joint member being a second sleeve providing a longitudinal threaded hole formed therein for inserting said another end of the steel rod, which covers and engages said threaded connector portion, and a second connecting adapter for joining said second sleeve to another connector node,
• said first sleeve comprising a first external threaded part formed on the outer surface of a node side thereof, the minor diameter of which is larger than the diameter of said swelled portion, a first polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said first sleeve for engagement of said first external threaded part to a longitudinal screw hole inside said first connecting adapter, a first adapter-contact face formed at the boundary between said first polygonal swelled part and said first external threaded part, which contacts said first connecting adapter, and a swelled portion-contact face formed at the end of the node side of the first external threaded part, which contacts a back surface of a counter-node side of said swelled portion,
• said first connecting adapter comprising a first joining threaded part formed on the outer surface of a node side thereof, the major diameter of which is smaller than that of said first external threaded part, a first polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said first connecting adapter for engagement of said first joining threaded part to said connecting screw hole of the connector node and a longitudinal screw hole for engaging said first external threaded part, and a first conical part formed between said first polygonal swelled part and said first joining threaded part, the diameter of the end of the node side of which is smaller than that of the end of a counter-node side thereof, having a first node-contact face formed at the boundary between itself and said first joining threaded part, which is able to contact the connector node,
• said second sleeve comprising a second external threaded part formed on the outer surface of a node side thereof, a second polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said second sleeve for engagement of said second external threaded part to a longitudinal screw hole formed inside said second connecting adapter, a second adapter-contact face formed at the boundary between said second polygonal swelled part and said second external threaded part, which contacts said second connecting adapter, an adjusting screw hole formed inside said second external threaded part, which communicates with said longitudinal threaded hole, and an adjusting screw bolt engaging said adjusting screw hole, which regulates the length of engagement of said threaded connector portion with said longitudinal threaded hole in response of the contact with said another end face of the steel rod,
• said second connecting adapter comprising a second joining threaded part formed on the outer surface of a node side thereof, the major diameter of which is smaller than that of said second external threaded part, a second polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said second connecting adapter for engagement of said second joining threaded part to said connecting screw hole of the connector node and a longitudinal screw hole for engaging said second external threaded part, and a second conical part formed between said second polygonal swelled part and said second joining threaded part, the diameter of the end of the node side of which is smaller than that of the end of a counter-node side thereof, having a second node-contact face formed at the boundary between itself and said second joining threaded part, which is able to contact the connector node,
• the depth of the longitudinal groove having a longitudinal screw hole of said first connecting adapter being defined to be equal to or more than the difference of the summation of the length of said first external threaded part, the length of said swelled portion and the length of said second joining threaded part from the length for generating a preferable elongation enough to introduce regulated pretension into the steel rod, and
• the spiral direction of said threaded connector portion being selected opposite that of said second joining threaded part.

A joint device for joining a pretensioned brace member to connector nodes on the diagonal line of a grid formed in a space truss structure assembled by using structural members, comprising:

• a brace member having a steel rod providing a swelled portion formed at one end thereof and a threaded connector portion formed on the outer surface of another end thereof, a first joint member for connecting Said one end of the steel rod to one connector node, and a second joint member for connecting said another end of the steel rod to another connector node,
• said first joint member being a first sleeve providing a longitudinal hole formed therein for inserting said steel rod, an end face of which contacts a back surface of said swelled portion so as not to fall off from said steel rod,
• said second joint member being a second sleeve providing a longitudinal threaded hole formed therein for inserting said another end of the steel rod, which covers and engages said threaded connector portion, and a connecting adapter for joining said second sleeve to another connector node,
• said first sleeve comprising a first joining threaded part formed on the outer surface of a node side thereof, the minor diameter of which is larger than the diameter of said swelled portion, a first polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said first sleeve for engagement of said first joining threaded part to a connecting screw hole of the connector node, a first node-contact face formed at the boundary between said first polygonal swelled part and said first joining threaded part, which is able to contact a flat face of the node, and a swelled portion-contact face formed at the end of the node side of the first joining threaded part, which contacts a back surface of a counter-. node side of said swelled portion,
• said second sleeve comprising an external threaded part formed on the outer surface of a node side thereof, a second polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said second sleeve for engagement of said external threaded part to a longitudinal screw hole formed inside said connecting adapter, an adapter-contact face formed at the boundary between said second polygonal swelled pan and said external threaded part, which contacts said connecting adapter, an adjusting screw hole formed inside said external threaded part, which communicates with said longitudinal threaded hole, and an adjusting screw bolt engaging said adjusting screw hole, which regulates the, length of engagement of said threaded connector portion with said longitudinal threaded hole in response of the contact with said another end face of the steel rod,
• said connecting adapter comprising a second joining threaded part formed on the outer surface of a node side thereof, the major diameter of which is smaller than that of said external threaded part, a polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said connecting adapter for engagement of said second joining threaded part to said connecting screw hole of the connector node and a longitudinal screw hole for engaging said external threaded part, and a conical part formed between said polygonal swelled part and said second joining threaded part, the diameter of the end of the node side of which is smaller than that of the end of a counter-node side thereof, having a second node-contact face formed at the boundary between itself and said second joining threaded part, which is able to contact the connector node,
• the depth of said connecting screw hole of the connector node being defined to be equal to or more than the difference of the summation of the length of said first joining threaded part, the length of said swelled portion and the length of said second joining threaded part from the length for generating a preferable elongation enough to introduce regulated pretension into said steel rod, and
• the spiral direction of said threaded connector portion being selected opposite that of said second joining threaded part.

A joint device for joining a pretensioned brace member to connector nodes on the diagonal line of a grid formed in a space truss structure assembled by using structural members,, comprising:

• a brace member having a steel rod providing a swelled portion formed at one end thereof and a threaded connector portion formed on the outer surface of another end thereof, a first joint member for connecting said one end of the steel rod to one connector node, and a second joint member for connecting said another end of the steel rod to another connector node,
• said first joint member being a first sleeve providing a longitudinal hole formed therein for inserting said steel rod, an end face of which contacts a back surface of said swelled portion so as not to fall off from said steel rod, and a connecting adapter for joining said first sleeve to one connector node,
• said second joint member being a second sleeve providing a longitudinal threaded hole formed therein for inserting said another end of the steel rod, which covers and engages said threaded connector portion,
• said first sleeve comprising an external threaded part formed on the outer surface of a node side thereof, the minor diameter of which is larger than the diameter of said swelled portion, a first polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said first sleeve for engagement of said external threaded part to a longitudinal screw hole inside said connecting adapter, an adapter-contact face formed at the boundary between said first polygonal swelled part and said external threaded part, which contacts said connecting adapter, and a swelled portion-contact face formed at the end of the node side of the first external threaded part, which contacts a back surface of a counter-node side of said swelled portion,
• said connecting adapter comprising a first joining threaded part formed on the outer surface to:
• a node side thereof, the major diameter of which is smaller than that of said external threaded part, a polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate said connecting adapter for engagement of said first joining threaded part to said connecting screw hole of the connector node and a longitudinal screw hole for engaging said external threaded part, and a conical part formed between said polygonal swelled part and said first joining threaded part, the diameter of the end of the node side of which is smaller than that of the end of a counter-node side thereof, having a first node-contact face formed at the boundary between itself and said first joining threaded part, which is able to contact the connector node,
• said second sleeve comprising a second joining threaded part formed on the outer surface of a node side thereof, a second polygonal swelled part having torquing surfaces formed on the outer surface thereof to rotate the second sleeve for engagement of said second joining threaded part to a connecting screw hole of another connector node, a second node-contact face formed at the boundary between said second polygonal swelled part and said second joining threaded part, which is able to contact a flat face of the node, an adjusting screw hole formed inside said second joining threaded part, which communicates with said longitudinal threaded hole, and an adjusting screw bolt engaging said adjusting screw hole, which regulates the length of engagement of said threaded connector portion with said longitudinal threaded hole in response of the contact with Said another end face of the steel rod,
• the depth of the longitudinal groove having a longitudinal screw hole of said connecting adapter being defined to be equal to or more than the difference of the summation of the length of said external threaded part, the length of said swelled portion and the length of said second joining threaded part from the length for generating a preferable elongation enough to introduce regulated pretension into the steel rod, and
• the spiral direction of said threaded connector portion being selected opposite that of said second joining threaded part.