The utility model discloses a device is prevented bumping by machinery, including the installation link plate, the installation link plate from the top down system of boring has a plurality of cotter holes, and the cotter hole of position is respectively through a set of U type card and derrick hypomere guide rail seat fixed connection about the installation link plate, fixed mounting has the slide on the installation link plate, installs gas accuse valve on the slide, and the guide pulley is installed to the driving lever outer end of gas accuse valve, and the driving lever of gas accuse valve passes through the spring and is connected with the dead lever on the slide. The utility model discloses the device can be adjusted and prevent bumping the height, and simple structure installs the dismantlement convenience, has remedied the defect of pounding the protection during machinery is prevented bumping under the nothing, prevents bumping the formation dual fail -safe with the electronics, has improved traveling and hoisting system's factor of safety greatly.