Rock excavating arched tunnel forming machine

A rock excavating machine for forming arch type underground roadways, comprising a body for arrangement in the underground roadway, a first forwardly extended forked support member on the body, a stay unit anchorable in the roadway, advancing ram means for interconnecting the body to the stay unit, a roof support assembly carried by the body, a forwardly extending large cutter carrying arm pivotally mounted on said forked support members for movement about a generally vertical axis and an upwardly extending large cutter carrying arm pivotally mounted on the body for movement about generally horizontal axis.

A rock excavating machine for forming an arch type underground roadway, comprising a body unit for arrangement in the roadway, a stay unit anchorable in the roadway, advancing means for interconnecting the body unit to the stay unit for advancing one unit along the roadway relative to the other unit, a curved roof support shield carried by the body unit, a forwardly extending cutter carrying arm pivotally mounted on the body unit for movement about a generally vertical axis, arching mechanism for moving the forwardly extending cutter carrying arm about said generally vertical axis, a shaft rotatably mounted on the body unit for movement about a generally horizontal axis, an upwardly extending cutter carrying arm drivably mounted on the shaft for movement about said generally horizontal axis, drive gear mechanism for rotating the shaft to arc the upwardly extending cutter carrying arm to and fro about said generally horizontal axis, and control means for controlling said mechanisms such that in use at any one time the cutter carrying arms traverse in opposite directions, the control means ensuring that two cutter carrying arms do not foul one another.