Patent ID: 6792332
Filing Date: 2004-09-14
Classification: B65H,G07B

Abstract:
A method for controlling the serial transport of articles to achieve a predetermined gap between transported articles, the method including:transporting a first article on a transport system; transporting a second article on the transport system immediately upstream of the first article; measuring a variable first velocity and first position for the first article; measuring a variable second velocity and second position for the second article; for each period in a periodic operating cycle adjusting a position of the second article based on the position of the first article as follows: (a) calculating a current gap between the first and second articles as a function of a distance between a trail edge of the first article and the lead edge of the second article; (b) subtracting the predetermined gap from the current gap, the resulting difference herein referred to as distance Xt; (c) calculating a displacement needed to decelerate the second article from the second velocity to the first velocity of the first article at a negative value of a maximum acceleration parameter, the calculated displacement referred to as distance Xdecel; and (d) if Xt is substantially the same as Xdecel, and the second velocity is different than the first velocity, accelerating the second article at a calculated acceleration so that Xt can remain substantially the same as Xdecel at the end of the current operating cycle period, the calculated acceleration being a function of the maximum acceleration parameter, the second velocity, and the first velocity.