Claims
- 1. In a mobile roof bolter having a rear frame, a center frame in front of the rear frame, pivotably connected to the rear frame, and a front frame in front of the center frame, pivotably connected to the center frame, the improvement comprising:
- (a) a temporary roof support in front of the front frame, extending along a longitudinal axis, pivotably attached to the front frame, said temporary roof support comprising:
- i. a main support frame pivotably connected to the front frame, extending along said axis;
- ii. a main support beam extending along said axis having a front end and a back end, said back end terminating above said main support frame, said main support beam adapted for raising and lowering above said main support frame, in a vertical plane extending along said axis;
- iii. a cross beam in a plane extending transverse to said axis, pivotably attached to said front end of said main support beam, for supporting a mine roof;
- iv. a ground-contact beam extending along said axis, below said main support beam, having a front end and a back end, said back end pivotably connected to said main support frame, said ground-contact beam adapted for raising and lowering said front end below said main support frame, in said vertical plane;
- v. telescopically extendable scissors pivot means extending between said front end of said main support beam and said front end of said ground-contact beam, for moving between an open and closed position, to raise and lower said front end of said main support beam and said front end of said ground-contact beam in relation to each other;
- vi. primary support cylinder means in said vertical plane, extending between said main support frame and said scissors pivot means,, for opening and closing said scissors pivot means;
- vii. leveling pivot means connecting said back end of said main support beam and said main support frame, for permitting said back end of said main support beam to raise and lower in said vertical plane in relation to said main support frame, when said scissors pivot means opens and closes, whereby said cross beam raises and lowers vertically in a plane transverse to said axis; and
- viii. means for pivoting said temporary roof support up and down in relation to the front frame about a horizontal axis transverse to said longitudinal axis.
- 2. The invention of claim 1 in which said scissors pivot means comprises:
- (a) a secondary support cylinder means for raising and lowering said main support beam, said secondary support cylinder means having a top end and a bottom end;
- (b) said top end of said secondary support cylinder means pivotably connected to said front end of said main support beam at a top strut pivot joint;
- (c) a secondary strut having a top end and a bottom end;
- (d) said top end of said secondary strut pivotably connected to said bottom end of said secondary support cylinder means at a scissors pivot joint; and said bottom end of said secondary strut pivotably connected to said front end of said ground-contact beam.
- 3. The invention of claim 2 in which said primary support cylinder means and said secondary support cylinder means are hydraulically actuated.
- 4. The invention of claim 3 further including hydraulic circuit means for opening said scissors pivot means by first actuating said primary support cylinder means and thereafter actuating said secondary support cylinder means.
- 5. The invention of claim 4 in which said hydraulic circuit means closes said scissors pivot means by first activating said second support cylinder means and thereafter actuating said primary support cylinder means.
- 6. The invention of claim 5 further comprising a foot weldment pivotably connected to said bottom end of said secondary strut and said front end of said ground-contact beam.
- 7. The invention of claim 6 in which said main support beam includes a pair of spaced-apart sidewalls.
- 8. The invention of claim 7 in which said leveling pivot means comprises:
- (a) a first pair of spaced-apart leveling links, each link contacting a different sidewall of said main support beam;
- (b) each link having a top end and a bottom end;
- (c) said top end of each link pivotably connected to said back end of said main support beam;
- (d) said bottom end of each link pivotably connected to a sidewall of said main support frame;
- (e) a second pair of spaced-apart leveling struts, each strut contacting a different sidewall of said main support beam;
- (f) said top end of each strut pivotably connected to said main support beam at a pivot joint between said back end and said front end of said main support beam; and
- (g) said bottom end of each strut pivotably connected to a front end of a sidewall of said main support frame.
- 9. The invention of claim 8 in which said cross beam comprises:
- (a) a pair of spaced-apart sidewalls extending between a first and second end; and
- (b) a rocker weldment pivotably connected to said cross beam at said first and second end.
- 10. In a mobile roof bolter having a front frame portion, the improvement comprising:
- (a) a temporary roof support in front of the front frame, extending along a longitudinal axis, pivotably attached to the front frame, said temporary roof support comprising:
- i. a main support frame pivotably connected to the front frame;
- ii. a main support beam extending along said axis having a front end and a back end, said back end terminating above said main support frame, said main support beam adapted for raising and lowering above said main support frame, in a vertical plane extending along said axis;
- iii. a cross beam in a plane extending transverse to said axis, pivotably attached to said front end of said main support beam, for supporting a mine roof;
- iv. a ground-contact beam extending along said axis, below said main support beam, having a front end and a back end, said back end pivotably connected to said main support frame, said ground-contact beam adapted for raising and lowering said front end below said main support frame, in said vertical plane;
- v. telescopically extendable scissors pivot means extending between said front end of said main support beam and said front end of said ground-contact beam, for moving between an open and closed position, to raise and lower said front end of said main support beam and said front end of said ground-contact beam in relation to each other;
- vi. primary support cylinder means in said vertical plane, extending between said main support frame and said scissors pivot means, for opening and closing said scissors pivot means;
- vii. leveling pivot means connecting said back end of said main support beam and said main support frame, for permitting said back end of said main support beam to raise and lower in said vertical plane in relation to said main support frame, when said scissors pivot means opens and closes, whereby said cross beam raises and lowers vertically in a plane transverse to said axis;
- viii. means for pivoting said temporary roof support up and down in relation to the front frame about a horizontal axis transverse to said longitudinal axis; and
- ix. hydraulic circuit means for selectively activating said primary support cylinder means and secondary support cylinder means during opening and closing of said scissors pivot means.
Parent Case Info
This application is a continuation-in-part of my copending application, Ser. No. 7-796,986, filed Nov. 25, 1991, now U.S. Pat. No. 5,156,497.
US Referenced Citations (14)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2804864 |
Aug 1979 |
DEX |
Continuation in Parts (1)
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Number |
Date |
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Parent |
796986 |
Nov 1991 |
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