Device and method providing redundant automatic clutch release and engine shut down on a drilling or production rig

A drilling control system for a drilling rig having a crown block and a traveling block, and having a drum receiving power from a motor or engine operatively engaged thereto through a clutch, and having a cable wound on the drum thereby providing translation of the traveling block toward and away from the crown block, and having a drum brake applicable for cessation of drum rotation, said drum brake and said clutch being powered by compressed air pressure communicated a pressure source, said control system having a normal state, and having an activated state ceasing said translation, said control system comprising:

• means for switching said control system between said normal state and said activated state;
• a system conduit engageable to said pressure source at an input end, said system conduit providing communication of said compressed air pressure through a first pathway to a first output;
• said first output adapted for communication of said compressed air pressure to said clutch;
• electronic means for flow control of said compressed air pressure along said first pathway;
• said electronic means for flow control having a default configuration directing said compressed air pressure to said first output when said control system is switched to said normal state;
• said electronic means for flow control having an activated configuration blocking communication of said compressed air pressure between said input of said system conduit and said first output, when said control system is switched to said activated state, thereby dividing said system conduit into a first end communicating with said input, and a second end communicating with said first output;
• said electronic means for flow control in said activated configuration causing a bleeding said compressed air pressure said second end of said system conduit to a vent;
• said electronic means for flow control in said activated configuration causing a communication of said compressed air flow from said first end of said system conduit, through a second pathway to said second output;
• said electronic means for flow control bleeding said compressed air pressure said second pathway to said vent, when said control system is switched from said activated state back to said normal state causing a return of said means for flow control to said default configuration;
• and
• whereby, with said means for switching said control system in said normal state said compressed air pressure is communicated to said first output to allow operation of said clutch, and when said means for switching said control system is switched to said activated state, said compressed air pressure is redirected from said first output to said second output to initiate application of said brake to engage said drum, and concurrently said compressed air pressure is bled from said second output providing a means to disengage and prevent said clutch from communicating power from said engine to said drum.