The elbow plate, also known as the toggle plate, is a critical safety and mechanical component in a jaw crusher. Located at the rear of the crusher, it serves as a simple yet highly effective fuse link. Its primary function is to transmit crushing force and support the bottom of the moving jaw. Most importantly, it is designed to be the weakest part in the system. If uncrushable material like tramp iron enters the chamber, the elbow plate will fracture or bend, instantly stopping the crusher and preventing catastrophic damage to more expensive components like the pitman and main frame. This sacrificial design ensures operational safety and minimizes repair costs and downtime.