Image Number 4 for United States Patent #5207357.
In the epoxy ejection gun disclosed herein, a bridge member which couples and drives a pair of push rods includes a forward facing seat or socket, e.g. of conical shape. A lead nut engageable with a rotatable lead screw is provided with a surface matching the seat. An adjustable spring is provided for biasing the interfitting parts. Rotation of the lead screw causes the lead nut to advance driving the push rods but pressure is controlled by the selected value of biasing force on the matching surfaces, excessive force allowing the lead nut to rotate with the lead screw rather than to advance.