shaft 77 accordingly as sector gear 76 is rotated by gear 75 seen in fig2 a corresponding rotation takes place by gears 80 and 90 gear 80 seen in fig2 the cooperative function of gears 80 and 90 and cams 85 and 95 respectively is the operation of reversing switch 83 and 93 thus as sector gear 76 is rotated for example in the direction indicated by 96 nose paddle 35 is rotated upwardly in the direction indicated by arrow 40 as this rotation of gears 80 and 90 gear 80 seen in fig2 continues cam 95 is moved against switch 93 once cam 95 actuates switch 93 the rotation of motor 60 seen in fig2 is reversed by the toggle action of reversing switch 53 also seen in fig2 thereafter gears 80 and 90 are rotated in the direction indicated by arrow 86 which in turn lowers nose paddle 35 downwardly in the direction indicated by arrow 41 as gears 80 and 90 gear 80 seen in fig2 rotate in the direction indicated by arrow 86 cam 95 moves away from switch 93 simultaneously however cam 85 of gear 80 moves toward switch 83 as cam 85 moves against switch 83 switch 83 is actuated producing a further reversing of motor 60 through the action of reversing switch 53 seen in fig2 as a result the direction of motor rotation and thereby rotation of sector gear 76 is again reversed moving gears 80 and 90 once again the direction indicated by arrow 96 and again raising nose paddle 35 this reversing action continues as cams 95 and 85 alternate.