Abstract: The invention is concerned with mine-roof supports, especially self-advancing mine-roof supports and provides a support comprising a base, a shield inclined downwardly and rearwardly towards the rear of the base and pivotally attached to said base, a roof-engaging canopy pivotally attached to an upper part of the shield, hydraulically; extensible prop means operatively positioned between the base and said shield, and hydraulically-extensible prop means operatively positioned between the base and the canopy. In some preferred embodiments of the invention the shield is a completely non-roof-engaging member and the pivotal connection between the shield and the baseis such that raising and lowering of the shield, by the prop means between said shield and the base, does not involve material angular displacement of said prop means. The pivotal connection between the canopy and the shield conveniently includes a debris excluding joint between said canopy and shield.

Abstract: A roof-engaging assembly for a mine roof support having prop or jack means to engage and support the roof-engaging assembly, comprises a rigid part to engage said prop or jack means, and a roof-engaging part positioned over and resiliently urged away from the rigid part. Preferably the rigid part has a roof-engaging face and a relatively stepped or recessed face below the roof-engaging face, the roof-engaging part being positioned over and resiliently urged away from the stepped or recessed face and towards positions above the roof-engaging face of the rigid part.

Abstract: The invention is concerned with a self-advancing mine roof support comprising a base, hydraulically extensible prop means mounted on said base and a roof-engaging structure, including a canopy, mounted on said prop means for application thereby to a roof to be supported. On at least one side of the roof support there is a laterally extensible and retractable auxiliary canopy and a device is provided for urging and extending said auxiliary canopy laterally outwardly with respect to the support. The auxiliary canopy on the support bears firmly against a similar auxiliary canopy on an abutment on a neighboring roof support so as to prevent roof material falling between the two supports. Because it is retractable, however, the auxiliary canopy does not interfere with the advance of the supports. Conveniently the auxiliary canopy comprises two box-like members fitted telescopically one within the other.

Abstract: A self-advancing mine roof support of which the ground-engaging structure comprises a pair of spaced apart skids in the spacing between which the relay bar structure of the advancing mechanism is housed, such structure being powered by a pair of pressure-fluid operated rams disposed one adjacent each of said two skids.