GB706037A - Improvements in chain stretching and testing machines - Google Patents

Abstract

706,037. Testing physical qualities of chains. ESSER, P., [trading as MEYER, ROTH & PASTOR, MASCHINENFABRIK]. May 11, 1951, No. 11146/51. Class 106 (2). [Also in Group XXII] A chain testing, stretching and marking machine through which the chain is fed step by step has means automatically operated by and controlled from a main driving shaft for feeding, testing stretching and marking lengths of the chain. A motor driven flywheel 2 turns the main driving shaft 5 through pinions 3 and 4. On the shaft 5 is a crank disc 31 coupled to a connecting rod 32 in a manner giving it an adjustable stroke of from zero to ninety millimetres. The connecting rod 32 imparts its stroke to a pivoted lever 34 through an adjustment nut 33 and the resulting reciprocating motion of the free end of the lever 34 moves a carriage 37 on the testing machine. The carriage 37 has means whereby on its forward stroke, as indicated by the arrow, the chain is gripped and moved forward with the carriage but such that on its return stroke the chain is released from the said gripping means. In this manner, lengths of the chain are continually fed forward step by step. The main driving shaft 5 is also continually coupled to two longitudinally extending shafts 12 arranged one on each side of the testing machine. The two shafts 12 each have means whereby after the chain has been fed forward, opposed tension jaws 18 on a fixed tension head 17 and opposed tension jaws 18<SP>1</SP> on a movable tension head 16 are caused to close on and grip the chain, whereafter the movable tension head 16 is given a predetermined longitudinal movement through a bell crank lever 14 operated by a cam action from the main driving shaft 5. The said movement stretches the chain links between the heads 16 and 17 to the required length. At the end of the stretching stroke the jaws are automatically caused to release their grip on the chain and the movable head 16 is returned to its starting position. The stationary head 17 is connected to one end of a cylinder 26 slidable in a fixed bearing 27, the cylinder 26 having at its other end a nut 29 and a pressure indicator 28 between the nut 29 and the bearing 27. The tension set up in the chain during the stretching stroke is thus transmitted to the pressure indicator 28 and should, by reason of a fault or by reason of an unduly stretched chain, a predetermined pressure not be attained, then by known electrical means, for example, a bell warning is given or the machine is automatically stopped, so that the faulty chain link can be removed. Instead of, or adjacent to the scale of the pressure indicator 28, a recording device may be provided that shows the result of each test. The machine includes a mark stamping device 42, operated from the main driving shaft 5, which, after each satisfactory test automatically marks a link of the chain length tested.