Login or register (free and only takes a few minutes) to participate in this question.
You will also have access to many other tools and opportunities designed for those who have language-related jobs (or are passionate about them). Participation is free and the site has a strict confidentiality policy.
Explanation: Under the word 'Dalén, Collins mentions 'an automatic light-controlled valve' known as 'Solventil'.
Although I have used the translation 'cut-off valve' earlier in relation to Nils Gustaf Dalén's invention (Nobel prize for physics 1912).