GB1344406A - Strip stretching and straightening installations - Google Patents

Abstract

1344406 Stretch levelling I UNGERER 18 Oct 1972 [21 Oct 1971] 47931/72 Heading B3E In a strip stretching and straightening installation having an S-roll backstay stand, an adjusting gear for the degree of stretch and an S-roll haul-off stand, each pair of rolls or group of rolls of each stand is driven by a differential gear 3 having one output shaft connected to one roll 2 or group, and another output shaft 5 connected to the other roll 1 or group through a transmission including a further differential gear 4 and variable gear means 6 for varying the output speed of gear 4 by varying the speed of its planet carrier 4a. In the arrangement shown, the variable gear 6 is infinitely variable, being driven by shaft 5 and connected to planet carrier 4a through a reduction gear 7, permitting fine adjustment of the speed of roll 1 relative to that of roll 2. Such adjustment may be made manually or automatically in response to variables such as the modulus of elasticity of the strip, coefficient of friction between strip and roll, or roll wear, so that the build up or fall off of tension through the stand can be controlled and slip avoided. In a four roll stand, each pair of rolls is driven as in Fig. 2, and the two input drive shafts 18 are themselves driven by a similar arrangement from a single input shaft. The rolls of the two stands are driven by a single motor, in one case directly and in the other case through a variable gear which controls the degree of overall stretch.