US3719394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for steering a longwall mineral mining machine
Assignee: Coal Industry Patents Ltd
•
Filing: 1971-01-11
•
Granted: 1973-03-06
•
Expires: 1991-01-11
Abstract
Abstract The invention relates to apparatus for steering longwall mining machines. The apparatus comprises an electromagnetic-radiation emitter/detector which is mounted on the end of an arm pivotally mounted on the machine. The emitter/detector is located immediately behind the machine''s rotary cutter and is urged by a hydraulic jack so as to remain close to the roof.
Inventors
- 👤 D Hartley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:33
CPC Classifications
E; E21; E21C; E21C35/00; E21C35/282
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
92 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine and which is connectable to a machine, means for connecting the arm to a machine and for vertically urging the emitter/detector, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the cutting horizon of the machine for avoiding unwanted steering action in response to a transient change associated with such a cavity.
Claim 2
Dependent Claim
92 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine and which is connectable to a machine, means for connecting the arm to a machine and for vertically urging the emitter/detector, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the cutting horizon of the machine for avoiding unwanted steering action in response to a transient change associated with such a cavity.
Claim 3
Dependent Claim
92 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine and which is connectable to a machine, means for connecting the arm to a machine and for vertically urging the emitter/detector, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the cutting horizon of the machine for avoiding unwanted steering action in response to a transient change associated with such a cavity.
Claim 4
Dependent Claim
92 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine and which is connectable to a machine, means for connecting the arm to a machine and for vertically urging the emitter/detector, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the cutting horizon of the machine for avoiding unwanted steering action in response to a transient change associated with such a cavity.
Claim 5
Dependent Claim
25 words
The apparatus of claim 1 wherein said means for connecting the arm to a machine and for vertically urging the emitter/detector, comprises a hydraulic jack.
Claim 6
Dependent Claim
17 words
The apparatus of claim 2 additionally comprising pivotal mounting means for connecting the arm to a machine.
Claim 7
Dependent Claim
128 words
Apparatus for steering a longwall mineral mining machine, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector first pivotal mounting means adapted to be connected to a machine for supporting the other end of the arm for upward or downward movement of the arm relative to a machine, means which act on the arm such that in operation the emitter/detector is urged towards the roof of the mineral seam, second pivotal mounting means for supporting the arm for horizontal movement of the emitter/detector relative to a machine and a roof cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the roof for avoiding unwanted steering action in response to a transient change due to such a roof cavity.
Claim 8
Dependent Claim
128 words
Apparatus for steering a longwall mineral mining machine, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector first pivotal mounting means adapted to be connected to a machine for supporting the other end of the arm for upward or downward movement of the arm relative to a machine, means which act on the arm such that in operation the emitter/detector is urged towards the roof of the mineral seam, second pivotal mounting means for supporting the arm for horizontal movement of the emitter/detector relative to a machine and a roof cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in the roof for avoiding unwanted steering action in response to a transient change due to such a roof cavity.
Claim 9
Dependent Claim
32 words
The apparatus of claim 4, in which the roof cavity detector comprises a member biased towards the roof for cutting out the effect of the emitter/detector upon upward movement of the member.
Claim 10
Dependent Claim
115 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine, said arm being connectable o a machine, means for connecting the arm to a machine and urging the emitter/detector vertically towards a boundary of a machine''s cutting horizon, pivotal mounting means connecting the emitter/detector to the said one end of the arm, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in a boundary of a machine''s cutting horizon for avoiding unwanted steering action in response to a transient change in the condition of saId boundary.
Claim 11
Dependent Claim
115 words
Apparatus for steering a longwall mineral mining machine in a mineral seam, comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine, said arm being connectable o a machine, means for connecting the arm to a machine and urging the emitter/detector vertically towards a boundary of a machine''s cutting horizon, pivotal mounting means connecting the emitter/detector to the said one end of the arm, and a cavity detector for cutting out the effect of the emitter/detector upon encountering a cavity in a boundary of a machine''s cutting horizon for avoiding unwanted steering action in response to a transient change in the condition of saId boundary.
Claim 12
Dependent Claim
74 words
A mineral mining machine provided with apparatus for steering said machine, said apparatus comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine, a hydraulic jack connecting the arm to the machine and for vertically urging the emitter/detector and a cavity detector for cutting the effect of the emitter/detector on the machine''s steering upon encountering a cavity in the cutting horizon of the machine.
Claim 13
Dependent Claim
74 words
A mineral mining machine provided with apparatus for steering said machine, said apparatus comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector for vertical movement relative to the machine, a hydraulic jack connecting the arm to the machine and for vertically urging the emitter/detector and a cavity detector for cutting the effect of the emitter/detector on the machine''s steering upon encountering a cavity in the cutting horizon of the machine.
Claim 14
Dependent Claim
22 words
The mineral mining machine of claim 7, in which said apparatus additionally comprises pivotal mounting means connecting the arm to the machine.
Claim 15
Dependent Claim
109 words
A mineral mining machine provided with apparatus for steering said machine, said apparatus comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector, first pivotal mounting means connected to the machine and supporting the other end of the arm for upward or downward movement of the arm relative to the machine, means for acting on the arm so that in operation the emitter/detector is urged towards the roof of the mineral seam, second pivotal mounting means supporting the arm for horizontal movement of the emitter/detector relative to the machine and a roof cavity detector for cutting out the effect of the emitter/detector on the machine''s steering.
Claim 16
Dependent Claim
109 words
A mineral mining machine provided with apparatus for steering said machine, said apparatus comprising an electromagnetic-radiation emitter/detector, an arm one end of which carries the emitter/detector, first pivotal mounting means connected to the machine and supporting the other end of the arm for upward or downward movement of the arm relative to the machine, means for acting on the arm so that in operation the emitter/detector is urged towards the roof of the mineral seam, second pivotal mounting means supporting the arm for horizontal movement of the emitter/detector relative to the machine and a roof cavity detector for cutting out the effect of the emitter/detector on the machine''s steering.
Claim 17
Dependent Claim
34 words
The mineral mining machine of claim 9, in which the roof cavity detector comprises a member biased towards the roof for cutting out the effect of the emitter/detector upon upward movement of the member.
Claim 18
Dependent Claim
23 words
The mineral mining machine of claim 9 in which the roof cavity detector is also carried by said one end of said arm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |