The general concept of an expansion connector is old. This type of connector comprises a first part which is in the nature of an insert and a second part which includes a socket for the insert. The insert is inserted into the socket and expanded to exert a clamping or holding force on the wall of the socket.
Examples of expansion connectors which can be found in the patent literature are shown by the following U.S. Pat.: Nos. 2,190,555, granted Feb. 13, 1940, to Charles A. Toce, Robert F. Broussard and William N. Woodruff; 2,281,279, granted Apr. 28, 1942, to David A. Fox; 2,798,748, granted July 9, 1957, to Albrecht Maurer; 3,009,747, granted Nov. 21, 1961, to Kenneth H. Pitzer; 3,135,033, granted June 2, 1964, to Samuel H. Jackson; 3,355,201, granted Nov. 28, 1967 to Leroy E. Barwick; 3,779,659, granted Dec. 18, 1973 to Roger Habert; and 4,134,703, granted Jan. 16, 1979, to Earl S. Hinners. Other expansion connectors are disclosed by my U.S. Pat. Nos. 4,667,916 and 4,691,889.
The mechanisms disclosed by these patents should be carefully considered for the purpose of putting the present invention into proper perspective relative to the prior art.
The present invention relates to the provision of a new and unique joint construction comprising a first member which includes an expansion insert. The insert is merely slipped endwise into a socket carried by the second member, and then one of the members is simply rotated relative to the other, and the insert functions to dig into the wall of the socket and in that manner securely connect the two members together.
Another object of the invention is to provide an improved mounting structure for a suspended object (e.g. a lighting fixture) which utilizes the joint construction, and which makes it possible for the user to disassemble and then later reassemble the mounting structure, without the use of destructive methods (e.g. removing parts by use of metal cutting equipment).
Ship construction is done in stages. Quite often, a component is installed and then it is discovered that the component must be removed in order to either install another component, or perform some other stage of the construction of the ship. Light fixtures must be securely affixed to the ceiling structure and this has in the past been done by welding the upper ends of support leg members to the ceiling and welding cross members to the lower ends of the support leg members, and then bolting the light fixtures to the cross members. When a mounting structure was installed in this way it became necessary to remove it in a destructive manner, such as by use of a cutting torch. The mounting structure of the present invention provides a way of easily connecting and disconnecting the parts of the mounting structure to each other and to the ceiling structure, so that if it becomes necessary to remove the mounting structure, it can be done without destructive affects to this component, so that such component can be reused. The mounting structure of the present invention makes it easy to raise or lower a lighting fixture or similar object. The mounting structure need only be disassembled and then reassembled with a longer or shorter support leg.