This invention relates to machinery for automated handling of thin, pliable material, such as fabric, and more particularly to apparatus which automatically forms a stack of sheets of the material from a long, continuous roll of the material.
The present invention has particular application in the mass production of wearing apparel. However, the principles of the present invention are generally applicable whenever handling of thin, pliable material is required, for instance, in the formation of pieces of a tent. In the apparel industry, fabric is received from the fabric manufacturer in the form of a roll and must be spread out for cutting into pieces which are later joined together to form the apparel. In common practice, the roll is spread out into a long stack consisting of layers of the fabric. The stack is cut to form the component pieces of the article of apparel to be produced. In this way, multiple pieces are formed with only a single cut.
Presently, the stack of material (referred to hereinafter as the "spread") is formed automatically by spread forming machinery including a gantry which is moved back and forth over the table on which the spread is formed. More specifically, the gantry includes a cradle in which the roll of fabric is held and which is operable to unroll the fabric for feeding a web of the fabric out of the gantry and onto the table as the gantry moves over the table. Fabric is frequently formed with an outer side having a design or finished appearance which will ultimately be on the outwardly facing side of the apparel. The inner side of the fabric has no design and/or is unfinished since it will not be seen when the apparel is worn. If a web of material is fed continuously out from the roll as the gantry moves both in a forward direction and a rearward direction over the table, the spread will be formed with adjacent layers of fabric facing different ways. In a so called "pair spread", one layer of fabric will have the outer side facing upward, and the adjacent layers will have their outer sides facing downward. One consequence of pair spreading is that when the spread is cut, pieces are formed which are mirror images of each other when turned so that both outer sides face the same way. Although both pieces are usable on the right and left sides of the article of apparel, it will be necessary to separate and divide out these pieces one from the other for later processing. Another consequence is that fewer pieces can be cut from the spread and more material will be wasted.
It is possible to form a "face up" or "face one way" spread in which all of the layers of fabric in the spread face the same way. However, to do this the gantry must be stopped at the end of its run in one direction (e.g., the forward direction) and the web of fabric fed out from the cradle cut away from the roll. The gantry must then travel in the rearward direction back to its start position with no fabric being fed out onto the table. Once the start position is reached, the gantry then travels forward again, feeding a web of material out onto the preceding web lying on the table as it goes. Thus, it may be seen that the formation of the face up spread takes at least twice as long as the formation of the pair spread because fabric is fed onto the table only when the gantry travels in one direction. The formation of the spread is a bottleneck in the manufacturing process. Thus, there is presently a need for spread forming methods and apparatus which permit rapid formation of face up spreads.
USPTO Backgrounds
USPTO Backgrounds