Method and apparatus for operating instruments subject to radiation

The method of protecting a radiation sensitive instrument against excessive radiation which comprises a positioning a protective shield for movement into and out of radiation shielding position with respect to said instrument, directing a fluid coolant at said instrument during such radiation, said fluid coolant being circulated by an electrically energized power source, and positioning said protective shield into radiation shielding position in response to a predetermined decrease in the electrical energization of said power source.

An apparatus for protecting an instrument subject to radiation against excessive radiation which comprises a radiation shield movable into a radiation shielding position between the radiation source and said instrument, means including a servo motor holding said radiation shield in radiation shielding position, holding means for holding said radiation shield out of said radiation shielding position, a release means operable to deactuate said holding means and thereby actuate said servo motor to bring said radiation shield into radiation shielding position, cooling means for cooling said instrument and sensor means associated with said cooling means and arranged to operate said release means upon change in the output of said cooling means.

An apparatus for the protection of a measuring instrument subject to excessive radiation which comprises a protective shield, positioning means for moving said protective shield into and out of a radiation shielding location with respect to said instrument, coolant circulating means for circulating a fluid coolant in proximity to said instrument, and means actuated by a decrease in the flow of said coolant to operate said positioning means to insert said protective shield into said radiation shielding position.