In response to difficulties we have observed in the field, DTS has created an entire graham drive replacement.
Experience has shown us that the graham drive transmission is easily damaged if adjustment is made while the process is stopped. It is also difficult to determine whether the graham drive is functioning properly during process operation. The DTS solution eliminates the graham variable speed transmission and replaces it with an electric motor at the powered out feed of Comco press and die cutting systems.
Currently, the graham drive transmission functions as a mechanism to advance or retard the web draw capability in the Comco press and die cutter out feed module. This web tension manipulation is accomplished by rotating the harmonic drive input shaft plus or minus in percentages of revolutions depending on the fixed web tension (the draw) required at the outfeed. Variable draw tension is required to compensate for caliper variation which changes roll pitch diameter and hence web speeds needed at the sheeting station.
The DTS method of operation references the speed of the line shaft and regulates electronic pulses to a servo motor which will incrementally phase the harmonic input drive shaft plus or minus the 2 percent web draw required. This adjustment range provides the draw flexibility needed for the wide caliper variations of web run on the Comco equipment. (photo 2)
A touch screen allows the draw to be adjusted statically or dynamically, as desired. It also easily enables the operator to change the draw percentage to hundredths of a percent. The touch screen can be locked out for process security.
The retrofit package consists of a small enclosure (12 inch x12 inch x 6inch), mounted to the out feed module. The touch screen can be mounted in this enclosure or mounted remotely for operator convenience. The DTS electro-mechanical solution can be installed by a DTS technician or your maintenance personnel in less than one shift of down time.