| 摘要 |
FIELD: mining industry, oil and gas equipment. SUBSTANCE: unit contains a frame of a transportation means, a mast with its lower end hinged to the frame, a hydraulic cylinder, a front support of the mast rigidly attached to the frame, and a linkage. The latter includes a first member with an end hinged to the frame. The linkage is also provided with a second member the lower end of which is fixed on the frame and the upper end is hinged with the other end of the first member. The hydraulic cylinder is hinged with the middle section of a rear support and with the upper end of the second member of the linkage, the first member of the linkage having a support interacting with the upper section of the rear support and the hydraulic cylinder being provided with a means to fix the mast in its retracted position. EFFECT: decreased dimensions of the unit in the transportation position, simplified design and increased operation safety under wind loads. |
