Patent ID: 8580168

Claim:
A system for controlling the linear movement of a molding machine movable platen, comprising: a driven gear train of rotatable gears associated with the movable platen of said molding machine, said rotatable gears including a central idler gear located substantially equidistantly between a plurality of tie bars passing through said movable platen, a second pair of idler gears intermeshed with and located on opposite sides of said central idler gear and substantially in line with a rotational axis thereof, a toothed tie bar nut associated with each tie bar, an idler gear disposed between and intermeshed with one of said gears of said second pair of idler gears and one of said tie bar nuts, and a drive gear intermeshed with one of said rotatable gears, said gear train adapted to impart linear motion to said movable platen when said rotatable gears are rotated; a sensor to count the teeth of a selected rotatable gear during the rotation thereof; and a controller in communication with said sensor, said controller programmed to convert a tooth count received from said sensor into a linear travel distance of said movable platen and to use said tooth count to monitor and control a subsequent linear movement of said molding machine movable platen.