US Patent 9139409 Weighted boom assembly

A boom assembly includes a lower boom, an intermediate member, an upper boom, an intermediate link, and an actuator coupled between the intermediate member and the upper boom. The lower boom includes an intermediate member end and a base end, and the base end is configured to be pivotally coupled to a lift device. The intermediate member is pivotally coupled to the intermediate member end of the lower boom. The upper boom includes a first end pivotally coupled to the intermediate member, and the intermediate link is coupled directly between the upper boom and the lower boom. The intermediate member includes a base portion positioned to carry structural loading and a weighted portion positioned to provide counterweight for the lift device.