Patent ID: 7578496

Claim:
A valve arrangement, comprising: a valve body defining an enclosure and having a bonnet connected thereto; a stem rotatably attached to the valve body and positioned at least partially within the valve body; a handle in operable communication with the stem and configured to rotate the stem; and an actuation portion including at least one roller and positioned distal from the handle and in direct or indirect contact with the stem, wherein the actuation portion is configured to move when the stem is rotated, wherein the stem includes a first thread portion and a second thread portion, the first thread portion having a first thread pitch and configured to interact with and move the actuation portion, and the second thread portion in communication with the bonnet and having a second thread pitch and configured to move the stem with respect to the body; wherein the second thread pitch is smaller than the first thread pitch; wherein the first thread portion is in the form of a barrel cam and defines a path in which the at least one roller is at least partially captured and along which the at least one roller travels when the stem is rotated, thereby moving the actuation portion between open and closed positions; and wherein the actuation portion is urged into a final, seated position when the stem is rotated through linear movement of the stem and actuation portion based upon the interaction between the second thread portion and the bonnet.