Great difficulty has been experienced in securing the ends of bars firmly together when arranged on the same line with each other, in the construction of bridges and other structures, and the object of this invention is to provide a simple and effective ptan for accomplishing this object. It consists in a novel and very simple method of clamping and securing the ends of metal bars, and uniting plates with the said bars, by which great strength is obtained. The invention is applicable, in almost all cases where it is required to connect the enis of iron bars. In our illustrations, Fig. 1 represcnts this contrivance applied to a portion of an iron bridge girder; Fig. 2 is a vertical transverse section of ditto ; Fig. 3 is a view of the slotted plates between the bars ; Fig. 4 is a horizontal section of the ends of two bars nearly brought together ; and Fig. 5 is a horizontal section of"ditto connected. Similar letters refer to like parts. A are a series of flat horizontal iron bars, arranged edgewise one above the other, and united to form part of the bridge girder. B is a plate iron sheathing, covering one side of the said series of bars. As the bars, A, extend the whole length of the bridge, they have to be composed cf several lengths or sections united at their ends, and the mode ia which these lengths or sections are united constitute the invention. The ends of the bars, A, are bent at right angles to form lugs, a, in which are formed narrow slots, b b, to receive a wedge or key, c. Between the lugs, a, of two lengths of bar iron, is fitted a plate, C, whose width is the same as the width of the bars, A A, and in which is formed a slot, J, of the proper width to receive the wedge or key, c. A vertical iron plate, D, is placed against the opposite side of thejoint to that from which the lugs, a a, project, and this plate, D, contains slots for the plate, C, to pass through. When the plate, C, is placed between the lugs, a a, and the plate, D, applied, the wedge or key, c, is inserted through the slots, b and a, of the lugs, a a, and plate, C, and a wedge, e, is inserted in the slot, a, outside of the plate, and when both wedges are driven tight, the joint between the two lengths of bars, A A, is secure. The sheathing, B, when used, is simply applied close to the bars, A, on either side, holes being provided in the sheathing for the plates, C C, or for said plates and lugs, a a, to pass through, according to the side on which the sheathing is placed. When a series of several bars are to be combined, by arranging them together endwise, the plates, D, are to be long enough to lay acroS8 the end of the whole series of said bars, and to serve for two joints ; but if a single line of bars only arc intended to be united, these plates, D, necd only be long enough to cover one joint. This simple combination of parts to accomplish a very desirable end was patented on the 9th of March, 1858. Any further information can be obtained by addressing the patentee, William McKibbin, San Francisco, Cal.
This article was originally published with the title "McKibbin's Method of Securing Metal Bars" in Scientific American 13, 48, 384 (August 1858)