System and method for controlling movement of a transfer system

A linkage for connecting a transfer system to a manufacturing system such as a stamping press, the linkage comprising:

• a driveable crank arm having a drive end and a swing end, the drive end being mountable to the manufacturing system;
• a lead arm having a head end, a tail end, and an intermediate section between its head and tail ends, the intermediate section pivotally attaching the lead arm to the swing end of the crank arm;
• a follow arm having a base end and a free end, the base end being mountable to the manufacturing system, the free end being attached to the tail end of the lead arm,
• wherein the head end of the lead arm is mountable to the transfer system so as to control movement of the transfer system between an operable position and a serviceable position when the crank arm is driven;
• and
• an adjustable drive mechanism connecting the manufacturing system to the transfer system to rotate the transfer system with respect to the manufacturing system as the crank arm is driven, wherein the drive mechanism allows selection of transfer system attitudes during movement based on desired operable and serviceable positions.

In combination with a stamping press, a system for indexing workpieces between workstations in the stamping press, the system comprising:

• a transfer system including at least one set of gripping assemblies for securing a workpiece, the transfer system being capable of indexing a workpiece from one workstation to another workstation;
• a driveable crank arm mounted to the stamping press;
• a plurality of swing arms connecting the crank arm to the transfer system, the plurality of swing arms being interconnected and defining a plurality of pivot connections so as to control movement of the transfer system between operable and serviceable positions when the crank arm is driven;
• and
• an adjustable drive mechanism connecting the manufacturing system to the transfer system to rotate the transfer system with respect to the manufacturing system as the crank arm is driven, wherein the drive mechanism allows selection of transfer system attitudes during movement based on desired operable and serviceable positions.

A method for controlling movement of a transfer system in a manufacturing system such as a stamping press, the method comprising the steps of:

• determining operable and serviceable positions for the transfer system based on die location and press geometry;
• selecting a crank arm, lead arm, and follow arm, each having a length based on the operable and serviceable positions;
• connecting the crank arm, lead arm, and follow arm so as to control movement of the transfer system between the operable and serviceable positions;
• determining desired transfer system attitudes in the operable and serviceable positions;
• selecting a reference gear, object gear, and first and second free gears, the gears having gear ratios based on the desired transfer system attitudes;
• mounting the reference gear to the stamping press at an end of the follow arm so as to preclude rotation of the reference gear with respect to the stamping press;
• mounting the object gear to the transfer system at an end of the lead arm so as to preclude rotation of the object gear with respect to the transfer system;
• mounting the first and second free gears at a pivot connection defined by the lead and follow arms, the first and second free gears being coupled for rotation together;
• connecting the reference gear to the first free gear with a first drive means;
• and
• connecting the second free gear to the object gear with a second drive means so as to rotate the object gear together with the transfer system as the transfer system moves between the operable and serviceable positions.