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US 4,231,685 AGranted
Roof support unit
AssigneeGewerkschaft Eisenhutte Westfalia
InventorsHarry Rosenberg, Lubomir Plevak
Life of this patent
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Abstract
A roof support unit for use in a mineral mining working has a roof shield supported on a floor sill by means of at least two hydraulic props. A goaf shield is pivotally linked to both the roof shield and the floor sill. At least one of the hydraulic props is inclined towards the face-side of the unit and engages the roof shield. At least one of the hydraulic props is inclined towards the goaf-side of the unit and engages the roof shield.
Claims8
A roof support unit for use in a mineral mining working, comprising:
- (a) a roof shield supported on a floor sill by means of at least two hydraulic props,
- (b) a goaf shield pivotally linked to both the roof shield and the floor sill,
- (c) at least one of the hydraulic props being inclined towards a face-side of the unit and pivotally engaging the roof shield,
- (d) at least another one of the hydraulic props being:
- (1) oppositely inclined towards a goaf-side of the unit,
- (2) pivotably attached to the roof shield at a point nearer the goaf-side thereof than the axis of the pivotal linkage between the goaf shield and the roof shield, and
- (3) passing through an aperture in the goaf shield, and
- (e) said at least one prop and said at least another one prop crossing between their ends.
5 more elements
Dependencies are inferred from the claim text.