Indexing device and method for a dual valve assembly

Abstract

In accordance to one or more aspects of the disclosure an indexing track for controlling a dual valve assembly includes a plurality of interconnected pressure-up and pressure-down slots that define sequence paths to translate the pin and to actuate the dual valve assembly to a first position when the pin is in a first track position, to a second position when the pin is in a mid-track position, and a third position when the pin is in a third track position.

What is claimed is: 
     
         1 . An indexing track for controlling a dual valve assembly, the indexing track comprising:
 a plurality of interconnected pressure-up slots and pressure-down slots that define sequence paths to translate a pin and to actuate the dual valve assembly to a first position when the pin is in a first track position, to a second position when the pin is in a mid-track position, and a third position when the pin is in a third track position;   a third position pressure-up slot extending in a first axial direction from the mid-track position to the third track position; and   a mid-track hold stop positioned axially between the third position pressure-up slot and the first track position, the mid-track hold stop blocking axial movement of the pin in a second axial direction from the third position pressure-up slot to the first track position.   
     
     
         2 . The indexing track of  claim 1 , wherein the indexing track comprises a return sequence path to move the pin from the mid-track position to the first track position, wherein the return sequence path comprises two pressure-up slots. 
     
     
         3 . The indexing track of  claim 1 , wherein the indexing track comprises:
 a third position pressure-up slot extending in the first axial direction from the mid-track position to an upper most position of the third track position;   a third position pressure-down slot extending in the second axial direction from the upper most position to the mid-track position;   a hold stop sequence path interconnecting the third position pressure-up slot and the third position pressure-down slot; and   a third position hold stop located on the hold stop sequence path.