GB411140A - Improvements in or relating to power press tools or the like - Google Patents

Abstract

411,140. Testing physical qualities of materials. SINCLAIR, H., 6, The Crest, Surbiton Hill, and FRASER, A., 43, Foxley Lane, Purley, both in Surrey. Dec. 1, 1932, No. 34058. [Class 106 (ii).] In power-press testing machines, power is transmitted through a hydraulic coupling of the kinetic type, the slip in the coupling automatically reducing the speed of the machine as resistance increases and enabling the machine to stop when the resistance rises to a predetermined value although the driving motor continues to rotate. In one form, working and retracting cylinders 2, 24, Fig. 1, and a tank 16 are connected under the control of valves 19, 20 to a pump 3 driven through the hydraulic coupling 5 from a continuously running motor 4. The coupling may have a slip characteristic suited to the particular operating conditions as described in Specification 385,086, [Group XXIX], and may have a scale 15, Fig. 3, indicating the maximum pressure to be generated ; by setting a desired indication against a pointer 14, the filling opening 12 of the coupling is disposed so that the degree of filling of the coupling is determined by overflow from the opening 12. In an alternative form of coupling, similar to one of the examples described in Specification 328,028, [Class 69 (ii)], the degree of filling of the coupling is determined by means of a scoop tube 29, Fig. 5, connected to return passages 32, 33 and to a manually operated reversible gear pump 35, Fig. 6, having a foot valve submerged in a reservoir 8<a>; a float 37 in the reservoir operates a pointer 14a over a pressure scale 15<a>.