Lever frame
![A mechanical lever frame inside the signal box at Knockcroghery in Ireland](/Images/godic/202501/24/Leverframe4820.jpg")
![Signal cabin of the CIÉ (Coras Iompair Éireann), Ireland, 1963.](/Images/godic/202501/24/Signal_Cabin_at_Athlone_West,_Co_Westmeath4820.jpg")
![A three-lever ground frame at Kyle of Lochalsh, released by Annett's key](/Images/godic/202501/24/Ground_frame_kyle4820.jpg")
![Everglades Junction signal box with its Westinghouse Brake & Signal Co. Ltd. Style 'L' Power Lever Frame](/Images/godic/202501/24/Everglades_interior4820.jpg")
Mechanical railway signalling installations rely on lever frames for their operation to interlock the signals and points to allow the safe operation of trains in the area the signals control. Located in the signal box, the levers are operated by the signalman.