Air cushion machine and method

A method of producing an interconnected string of air cushions from a supply of plastic film with an air cushion machine for cushioning at least one item to be shipped in a box, the machine configured to inflate each air cushion in the string of air cushions to a variable inflation value selected from a range of inflation values, the machine having an inflation assembly for injecting air between plies of the film, a pulling assembly for pulling the film through the machine, and a longitudinal sealing assembly for sealing the plies of the film, the method comprising the steps of:

• determining a void volume defined by a difference between a volume of the box and a volume of the at least one item to be shipped in the box,
• determining a quantity of air cushions in the string of air cushions, each of a substantially identical length and width, to be produced and the variable inflation value for each air cushion in the quantity of air cushions such that a total air cushion volume of the quantity of air cushions in the string of air cushions produced is equal to the void volume,
• wherein each air cushion in the string of air cushions is prescribed with a unique inflation value that may vary from cushion to cushion within the string of air cushions,
• wherein each air cushion in the string of air cushions has a minimum allowable inflation value such that the air cushion will function effectively as cushioning material and a maximum allowable inflation value such that the air cushion will function effectively as cushioning material and not risk bursting,
• wherein the step of determining the inflation value for each air cushion in the string of air cushions provides a value within a range from the minimum allowable inflation value to the maximum allowable inflation value,
• and further wherein:
• the inflation assembly is controlled to vary an output pressure of the inflation assembly, the pulling assembly is controlled, and the sealing assembly is controlled, to produce the determined quantity of air cushions in the string of air cushions and the inflation value for each, or
• the inflation assembly is controlled to produce a constant output pressure of the inflation assembly, the pulling assembly is controlled to vary the speed of the film and thus the amount of time that the forming air cushions are exposed to the inflation assembly to thereby vary the inflation value, and the sealing assembly is controlled, to produce the determined quantity of air cushions in the string of air cushions and the inflation value for each;
• and
• producing the determined quantity of air cushions in the string of air cushions with the air cushion machine, and then
• repeating the above steps for a subsequent item to be shipped in a subsequent box to determine a subsequent different quantity of air cushions in a subsequent interconnected string of air cushions having a subsequent different total air cushion volume equal to a subsequent different void volume, and
• producing the subsequently determined quantity of air cushions in the subsequent string of air cushions,
• without manual input from an operator.