US Patent 10106140 Spring brake chamber

A spring brake chamber includes a first case, a second case, and a coupling case. The first case includes an open end, a closed end, and an open end portion. The open end portion of the first case includes a tapered outer positioning portion having a diameter that increases toward the open end. The coupling case couples the first case and the second case. The coupling case includes an open end closer to the first case and an open end portion. The open end portion of the coupling case includes a tapered inner positioning portion having a diameter that decreases toward the open end. The first case is positioned relative to the coupling case by attaching the outer positioning portion to an outer side of the inner positioning portion.