|
GB623424A
|
|
Improvements in, or relating to rotary drilling machines for operating in rock, coaland the like
|
|
GB637723A
|
|
Improved method of operating in rock, coal and the like
|
|
GB612560A
|
|
Improvements in portable drilling machines
|
|
GB446310A
|
|
Improvements in drilling machines for operation in rock, coal or other material
|
|
GB441152A
|
|
Improvements in, or relating to, drilling machines
|
|
GB349659A
|
|
Improvements in, or relating to, coal cutting machines and the like
|
|
GB297710A
|
|
Improvements in, or relating to, rotary driven coal cutting machines and the like
|
|
GB255233A
|
|
Improvements in valve apparatus for rock drills and other fluid pressure operated tools
|
|
GB232722A
|
|
Improvements in or relating to valve apparatus for percussive rock drills and like fluid pressure operated tools
|
|
GB198712A
|
|
Improvements in or relating to rotary driven coal cutting machines and the like
|
|
GB159666A
|
|
Improvements in and relating to cocks or valves for the control of fluid pressure
|
