with the front and rear sliding bearings 1 and ram 2 the mechanism returns to the positions shown in fig2 21 and 22 in the example shown in fig1 u2013 25 the angle of link 3 is controlled so that its angle to ram 2 never exceeds 0 2 degrees this represents an improvement in link 3 angle by a factor of 12 fig2 is a graphical representation of the link 3 angles of both the traditional drive and the new drive this is based on an actual operating beverage can metal forming press and as such due to manufacturing tolerances the values in the graphs are slightly different from the above discussion fig2 shows the reduction of link 3 angles throughout the machine stroke fig2 is a graphical representation of the vertical forces transmitted by link 3 to ram 2 of both the traditional drive and the new drive this is based on an actual operating beverage can metal forming press and as such due to manufacturing tolerances the values in the graphs are slightly different from the above discussion this graph shows that the normal forces are reduced from an absolute magnitude of 500 lbs to an absolute magnitude of 80 lbs the reduction in vertical forces greatly reduces deflection of the forming punch in the forming dies the reduced deflection greatly improves the accuracy of the formed part and also greatly improves forming tool life the above discussion referred to crankshaft 7 indexing approximately 90 degrees to each of the various stroke positions machines utilizing this type of drive linkage are quick return mechanisms therefore they inherently have unequal degree durations for ram motion on the forward stroke and the return stroke in the.