GB1374093A - Apparatus for sorting and handling mail - Google Patents

Abstract

1374093 Sorting postal mail MASSON SCOTT THRISSELL ENG Ltd 13 Dec 1972 [15 Dec 1971] 58262/71 Heading B8A Compartments 12 of a letter sorter are discharged into compartments of a shelf unit 70 (Figs. 2 and 4), which is mounted to traverse vertically, collecting stacks of letters from the vertically extending series of horizontally extending rows of the sorting compartments 12. The unit 70 when full, has its letters discharged into compartments of an output conveyer 21. Each compartment 12 has a base 34 for the letters which is counterbalanced by a spring 40. When the base 34 reaches its lowest position it operates a switch SW1 connected to logic circuitry (not described in detail in the Specification). The base may also be lowered by the operation of a motor driving a drum 54. This winds in a cable which passes over pulleys 56, 58, 59, and 60, and is anchored to a pusher plate 45. The latter is connected by a cable 53 to a spring drum unit having a lower return force than the spring 40. Deflection of the pusher plate 45 is blocked by the action of a roller 63 carried by the base 34, until the latter reaches its lowest position. When the pusher plate 45 then moves to deflect the stack into the corresponding compartment of the unit 70, vertical upward return movement of the base 34 is prevented by the action of an interlock roller 64. The plate 45 operates a switch SW2 at the end of its outward travel. Any letters above a predetermined maximum of the stack are retained by a plate 31 and are supported by a horizontal plate 51 which travels with the pusher 45. The plate 51 also serves to support any letters which arrive in the compartment 12 during the stack discharge operation. Sorting can thus be continued while the compartments 12 are being discharged. Photo-electric sensors 84 are responsive to the presence of letters in each compartment 82 of the shelf unit 70. When the latter is in its topmost position (Fig. 2), its compartments are discharged to compartments (104) (Fig. 1, not shown) of a conveyer 21 by pushers 90 slidably mounted on rods 94 (Fig. 7), and connected to endless drive belts 91. Each compartment (104) has a sensor not shown which prevents operation of the pushers 90 until every compartment 104 in line with the compartments of the shelf 70, is empty. The conveyer 21 leads to a bundling machine.