through the cavity of collar 22 and is vertically aligned thereby the free end of the axle 58 is eccentrically attached to a circular drum 59 which has an outer periphery 61 disposed in contacting relationship which an upper horizontal surface of a low friction plate 62 constructed of teflon or another suitable material the low friction plate 62 is rigidly attached to an upper horizontal surface of frame 11 as most clearly shown in fig4 and 5 referring now to fig5 and 7 the pan support assembly 14 shown at the forward end of the pan 13 is vertically aligned by cooperation of the housing 23 with the cavity of collar 22 an adjustable stop plate 63 extends downwardly within the cavity of collar 22 to contact the axle housing 23 the stop plate is adjusted by operation of a threaded rod 64 which threadably engages the top member of collar 22 fig5 shows the pan support assembly 14 in the starting position where the axle 58 is in the uppermost position with respect to the lower periphery 61 of the drum 59 and the axle housing 23 supports the pan in its highest position as the drum 59 rotates about the axis of axle 58 the pan 13 supported by the contacting relationship of the axle housing 23 with the stop plate 63 is vertically lowered to the position shown in fig7 where the axle housing 23 disengages from the stop plate 63 and the entire weight of the pan 13 is carried by the.