Remotely controlled thermal actuator

An arrangement for the remote control of an actuator is described. It comprises an energy transmitting conduit, a radiant energy source for transmitting radiant energy along the conduit from one end thereof and an actuator, at the other end. The actuator comprises a chamber containing a volatile liquid, which on receipt of energy from the radiant energy source, is caused to vaporize to displace a valve-operating element. The energy may be I.R. microwave, heat or from a laser. The conduit is pressurised and when the element is sufficiently displaced the pressure is available via a conduit and port as power source. The apparatus is for use in under sea oil installations, chemical and nuclear power industries and for the remote control of vehicles. (author)