US4490076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Underground support devices
Assignee: Joy Global Industries Ltd
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Filing: 1982-09-24
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Granted: 1984-12-25
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Expires: 2002-09-24
Abstract
Abstract An underground support, e.g. for the roof of a mine, has a roof engaging canopy 10 which can be raised and lowered in a controlled manner by hydraulic legs 14. Inflatable flexible membrane means, for example in the form of bags 12, are provided on the upper face of the canopy 10, which shape themselves to the mine roof and distribute loading evenly thereto. Inflatable flexible membrane means may also be used to prevent flushing of loose debris between adjacent supports, and on roadway supports.
Inventors
- 👤 Archelaius D. Allen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:20
CPC Classifications
E; E21; E21D; E21D23/00; E21D23/04; E21D23/06; E21D23/16
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
100 words
An underground support device comprising: (a) hydraulic drive means; (b) a substantially rigid support structure movable by the hydraulic drive means between a first position in which the substantially rigid support structure is spaced away from a surface to be supported and a second position in which the substantially rigid support structure is adjacent to the said surface; (c) Control means controlling said hydraulic drive means; (d) flexible membrane means mounted on said rigid support structure; (e) fluid pressure means operable to inflate the membrane, hence shaping the flexible membrane means to said surface and distributing the loading evenly thereto.
Claim 2
Dependent Claim
100 words
An underground support device comprising: (a) hydraulic drive means; (b) a substantially rigid support structure movable by the hydraulic drive means between a first position in which the substantially rigid support structure is spaced away from a surface to be supported and a second position in which the substantially rigid support structure is adjacent to the said surface; (c) Control means controlling said hydraulic drive means; (d) flexible membrane means mounted on said rigid support structure; (e) fluid pressure means operable to inflate the membrane, hence shaping the flexible membrane means to said surface and distributing the loading evenly thereto.
Claim 3
Dependent Claim
24 words
An underground support device as claimed in claim 1, in which the said hydraulic drive means and the said fluid pressure means are interconnected.
Claim 4
Dependent Claim
21 words
An underground support device as claimed in claim 1, in which the flexible membrane means comprises at least one inflatable bag.
Claim 5
Dependent Claim
31 words
An underground support device as claimed in claim 1, in which the flexible membrane means comprises at least one sheet of material sealed to the support structure around the sheet edges.
Claim 6
Dependent Claim
26 words
An underground support device as claimed in claim 1, in which the flexible membrane means is constructed of flexible synthetic material with reinforcing means embedded therein.
Claim 7
Dependent Claim
50 words
An underground support device as claimed in claim 1, comprising a hydraulic roof support having a base, a roof engaging unit, at least one hydraulic leg extending between the base and the roof engaging unit, the flexible membrane means being mounted on the upper face of the roof engaging unit.
Claim 8
Dependent Claim
63 words
An underground support device as claimed in claim 6, in which the flexible membrane means is located in at least one recess in the roof engaging unit, and the depth of the recess is related to the thickness of the uninflated flexible membrane means such that the uninflated flexible membrane means does not project above the upper face of the roof engaging unit.
Claim 9
Dependent Claim
71 words
An underground support device as claimed in claim 6, in which the flexible membrane means is inflatable as a separate operation from hydraulic operation of the leg, for example so that after the roof engaging unit has been set against the surface to be supported with a predetermined pressure, the flexible membrane means can be inflated to fill any gaps between the roof engaging unit and the surface to be supported.
Claim 10
Dependent Claim
28 words
An underground support device as claimed in claim 6, in which the flexible membrane means is inflatable as an operation related to the hydraulic operation of the leg.
Claim 11
Dependent Claim
37 words
An underground support device as claimed in claim 9, in which the inflation of the flexible membrane means is controlled by a valve which comes into operation when the pressure in the leg reaches a predetermined value.
Claim 12
Dependent Claim
22 words
An underground support device as claimed in claim 6, in which a separate fluid supply is provided for the flexible membrane means.
Claim 13
Dependent Claim
77 words
An underground support device as claimed in claim 6, in which the fluid supply for the flexible membrane means and the hydraulic supply for the leg are linked together such that lowering of the leg causes the pressure and volume of fluid in the flexible membrane means to fall and the flexible membrane means to at least partially empty, and raising the leg causes the pressure and volume of fluid in the flexible membrane means to rise.
Claim 14
Dependent Claim
46 words
An underground support device as claimed in claim 6, in which the pressure in the flexible membrane means is controlled such that if it rises above a predetermined limit, the leg lowers slightly to reduce the pressure and/or volume of fluid in the flexible membrane means.
Claim 15
Dependent Claim
42 words
An underground support device as claimed in claim 1, in which the flexible membrane means is mounted at at least one side of a hydraulic roof support to provide side sealing between adjacent roof supports to prevent material flushing between the supports.
Claim 16
Dependent Claim
36 words
An underground support device as claimed in claim 1, in which the flexible membrane means is mounted on an extension bar which is extendable from the roof engaging beam or canopy of a hydraulic roof support.
Claim 17
Dependent Claim
35 words
An underground support device as claimed in claim 15, in which the extension bar comprises a channel member with the mouth of the channel facing upwardly, the flexible membrane means being accommodated in the channel.
Claim 18
Dependent Claim
27 words
An underground support device as claimed in claim 1, comprising a roadway support of the form having hydraulic legs and being advanceable with a mine roadway heading.
References Cited (Backward Citations)
US2861429A
Cited
SU378630A1
Cited
SU473837A2
Cited
US3890792A
Cited
US3881776A
Cited
DE2533608A1
Cited
SU653396A1
Cited
SU773282A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |