Patent GB-190109914-A (GB)
Title: Improvements in the Manufacture of Chain
Inventor: WIRTZ LUIS
Filed: 1901-05-13
Granted: 1902-08-13
Abstract: 9914. Wirtz, L., and Freeman, F. May 13. Making chains.-Links are formed of wire coiled and subjected to pressure to weld the coils together, the wire may be heated electrically before coiling. Figs. 1, 4, and 5 show a machine for making the chain. The wire is led off from a drum a to the rotating mandrel b over a series of guide and feeding rollers; between the rollers a<4>, a<7> it is heated by an electric current. The mandrel is in two parts, each in the form of a circular disc with a boss of the shape of the link to be produced ; the discs are mounted to rotate in carriages g, which may be drawn apart to liberate the link by levers g<3>, they are toothed on their outer faces and are driven by spur and bevel gearing from short spindles which are connected by chain gearing to the countershaft e. The welding-dies i, adapted to enter the groove formed by the discs of the mandrel, are worked by hydraulic rams k, l pressure is admitted behind the rams k to advance the dies ; when it is cut off, the rams l, which are permanently under pressure, withdraw them. During the welding operation the mandrel is supported by two plungers provided with means for the supply of cooling-water, arranged in its axis and operated, like the dies i, by rams such as k, l. When the dies and plungers move back the liberated link drops on to spring fingers o fixed on the top of a cylinder o', through which the chain is delivered. The cylinder is formed with an internal helical groove to engage a thread on a fixed cylinder o<4>, so that when rotated through an angle of 90‹, by rack- and-pinion mechanism connected to one of the plungers, it also moves downwards. The link is then turned and lowered into position to allow the two halves of the mandrel to close together with its upper end in the opening b<o>, the radial slot bx allowing this. The coiling of a new link through the link so held then begins. The cylinder o<1> is connected by pawl and ratchet to a table p over which the finished chain is delivered ; so this table is moved forwards intermittently but always in the same direction the return movement of the cylinder to replace the finger in position to receive the new link being inoperative. The rollers a<5>, a<8> are connected by a chain a<17>, and are driven by chain gearing from the countershaft. In order to bring up the wire between the two halves of the mandrel to clamp its end in place before the coiling begins, the outward movement of one of the dies i is caused to rotate the roller a<8> by pawl and ratchet, the chain-wheel by which the roller is normally rotated being mounted so as to allow the shaft to over-run it. When the requisite amount of wire has been coiled the clutch e<1> on the countershaft, is thrown out of action to stop the feeding mechanism and the rotation of the mandrel and at the same time positive stops are advanced into the paths of pins on the gearing of the mandrel so that this is arrested with its slot bx upwards ; the wire is cut by a cutting edge on one of the dies i. The countershaft is driven from the main shaft d, this carries a roller formed with cam grooves by which the distribution of water to the rams of the dies and plungers, the to-and-fro movement of the halves of the mandrel and the positive stops for its rotation are controlled. The machine is stopped automatically when the wire on the drum a is used up ; the belt t<7>, which drives the main shaft d, is thrown off the fast and on to the loose pulley by a belt-fork having a spring on its stem. Normally the belt-fork is held with the belt on the fast pulley by a collar t<2> engaging a bell-crank lever t<1> ; this lever forms the armature of an electromagnet in the electric circuit by which the wire is heated, so that when the wire runs off the roller a<4> and the circuit is broken the armature is no longer attracted and obeying the pull of the spring t<9>, the lever is drawn away from the collar t<2> and the belt fork is thrown over by its spring. The stoppage may be indicated by a bell v<2> in a local circuit which is completed when the main circuit is broken.