A vertical rack-type spline-forming machine based on a novel slide base arrangement comprising a pair of vertical slide bases structurally joined by a symmetrically arranged set of tie bars. The structurally-joined vertical slide bases can be rested in an upright position on a non-structural space frame which provides improved access and lift capabilities to the vertical machine. The machine also includes a novel drive system using independent electric motors, one motor associated with each vertical slide base to drive the rack on that base through a roller screw shaft mechanism. The racks are further electronically synchronized through position signals communicated between the motor drives, and the rack home positions are calibrated with electronic "datums" programmed into the motor drives and capable of being re-calibrated in programmable fashion if one of the racks loses synchronicity.
There is disclosed a coldforming machine in which the rolling racks are preferably arranged in vertical direction and are adjustable via a feed means during the rolling operation in radial direction with respect to the workpiece to be formed.
There is disclosed a coldforming machine in which the rolling racks are preferably arranged in vertical direction and are adjustable via a feed means during the rolling operation in radial direction with respect to the workpiece to be formed.
The tensioner assembly is provided for clamping at least two objects and comprises a tie rod member, a thrust ring positioned on the tie rod member against one of the objects, a first retaining member for removably engaging a distal end of the tie rod member, and a second retaining member for removably engaging the distal end of the tie rod member between the thrust ring and said first nut member and spaced apart therefrom. Each of the first and second retaining members is provided with a set of jackbolts adapted to engage complementary holes therein and to extend from the holes to compressively bias the thrust ring. The total load experienced by the tensioner assembly is shared by two retaining members so that load carried by the first retaining member remains substantially constant during operation, while the second retaining member is subject to stress variation.
