| 摘要 |
The invention is an improvement for a combination mining machine and roof bolting apparatus in which the roof bolting mechanism is pivotable and can be used to install roof bolts in more than one location without moving the mining machine. The improvement is a pivotable canopy which pivots independently of, but in association with, the bolting apparatus. It comprises a canopy shield pivotably and cantileveredly mounted on the upper section of a telescopically-extensible mast. The telescopic mast absorbs all the moment loads, while the hydraulic extension cylinder disposed interiorily of the mast incurs only axial compressive loading. |
