Apparatus and method for making a resilient unit

Abstract

Apparatus for forming a resilient unit comprises a conveyor () and first and second spring supply stations (and), arranged in use to deposit respectively first and second spring types (and) under compression onto the conveyor. The conveyor is arranged in use to convey a row of the springs () in a direction shown by Arrows Atowards pocketing station (). At the pocketing station () the springs are urged from the conveyor into positions between upper and lower sheets (and), by a plurality of inserter devices () that move together in a reciprocating fashion in the direction of arrow A, before retracting to the position shown. After each row of springs is inserted between the sheets (), upper and lower computer-controlled welding tools (not shown) come together at positions P between the springs to join the sheets together, forming pockets in which the springs are encased. After each welding event the resilient unit is indexed forwards a distance equal to one pocket width in the direction of Arrows Aby computer-controlled drive means (not shown). The next row of springs is then conveyed into position ready for insertion between the sheets of material, and the process is repeated. The two spring supply stations are arranged to supply springs that differ from one another in at least one characteristic.