Patent ID: 8789616
Filing Date: 2014-07-29
Classification: A62C,F16L,F17D,Y10T

Abstract:
1. An apparatus comprising: a foreline for conveying a waste stream drawn from a process chamber to a pumping mechanism, the foreline comprising an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass around the isolation valve; and a controller for actuating the isolation valve, wherein the controller is configured to: cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber so that the waste stream is conveyed to the pumping mechanism via the bypass, the bypass comprising means for inhibiting propagation of a flame front therethrough, wherein the inhibiting means comprises valve means for effecting a variable restriction to the flow of a waste stream therethrough, wherein the controller is configured to cause the valve means to be closed prior to operation of the pumping mechanism, and opened when a pressure within a region between the valve means and the pumping mechanism has been reduced below a value at which propagation of a flame front within the waste stream can be sustained and wherein the controller is configured to prevent initiation of operation of the pumping mechanism unless the valve means is closed; and cause the isolation valve to be opened when a pressure within a region upstream of the isolation valve has been reduced below a value at which propagation of a flame front within the waste stream can be sustained.