Vehicle semi-trailer, e.g. for transporting boat or camping equipment - has brakes controlled by thrust on trailer king-pin measured by resistance strain gauges

摘要

A semi-trailer has at least one axle and brakes for its wheels. Under an extension at the front is a kingpin which fits into the carrying saddle of the tractor. The brakes are controlled by the thrust on the kingpin. This thrust is determined by stress or strain gauges. The kingpin is rigidly attached to a plate that can slide backwards and forwards by a short distance, the plate moving on rollers in the guide rails that form the sides of the trailer extension. There are buffers to limit this movement. A rod extends from the plate to a cylinder fixed behind it to the extension and which contains a strong spring. ADVANTAGE- Self-braking semi-trailer needing no direct connection to tractor's braking system.