US3894772A - Hydraulically actuated apparatus for the mechanical splitting of rock - Google Patents
Hydraulically actuated apparatus for the mechanical splitting of rock Download PDFInfo
- Publication number
- US3894772A US3894772A US489032A US48903274A US3894772A US 3894772 A US3894772 A US 3894772A US 489032 A US489032 A US 489032A US 48903274 A US48903274 A US 48903274A US 3894772 A US3894772 A US 3894772A
- Authority
- US
- United States
- Prior art keywords
- presser
- cheek
- head
- cheeks
- slider wedge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000011435 rock Substances 0.000 title claims abstract description 20
- 238000006073 displacement reaction Methods 0.000 claims abstract description 9
- 238000010276 construction Methods 0.000 claims description 12
- 230000000295 complement effect Effects 0.000 claims description 4
- 238000003780 insertion Methods 0.000 claims description 3
- 230000037431 insertion Effects 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 3
- 230000000284 resting effect Effects 0.000 claims description 2
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000002184 metal Substances 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000009435 building construction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229920000136 polysorbate Polymers 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C37/00—Other methods or devices for dislodging with or without loading
- E21C37/04—Other methods or devices for dislodging with or without loading by devices with parts pressed mechanically against the wall of a borehole or a slit
Definitions
- Apparatus of this type may consist of a cylinder block having a hydraulically actuatable, longitudinally movably piston arranged therein, with this piston acting, by way of a slider wedge which is connected to the piston rod, on headed presser cheeks which can be inserted in drill holes and laterally moved, the presser cheeks having an obliquity which corresponds to the inclination of the slider wedge, and with the head of one of the presser cheeks being U'shaped and having arms which engage opposite sides of the slider wedge.
- the heads of the presser cheeks By arranging for the heads of the presser cheeks to engage one in the other, all axial displacements or axial loads of one of the presser cheeks being transmitted, uniformly and in the same direction, to the other presser cheek, the U-shaped head of one of the presser cheeks being radially shiftably suspended in a hollow member and engaging round a reduced neck portion of the head, which is T-shaped in longitudinal cross-section, of the other presser cheek.
- Apparatus of this type may consist of a cylinder block having a hydraulically actuatable, longitudinally movably piston ar ranged therein, with this piston acting, by way of a slider wedge which is connected to the piston rod, on headed presser cheeks which can be inserted in drill holes and laterally moved, the presser cheeks having an obliquity which corresponds to the inclination of the slider wedge, and with the head of one of the presser cheeks being U-shaped and having arms which engage opposite sides of the slider wedge.
- the presser cheeks are either directly connected to the cylinder block, or are indirectly connected thereto by means of a hollow member which is detachably mounted on the cylinder block. In the latter instance, the heads of the presser cheeks lie within the hollow member.
- the above-mentioned rockbreaking apparatus is so constructed that an angle of inclination between cylinder block and insert presser cheeks of up to is permissible.
- the angle of inclination is greater, the infeed of fluid pressure medium must be interrupted, and a further rockbreaking apparatus be brought into service in the vicinity of the drill hole, although the first rock breaking apparatus still has power available.
- both presser cheeks are arranged so as to be axially shiftable within the hollow member and the pulling forces are taken up by tie-bars and guide-bars which are rigidly connected to the cylinder block, the presser checks are radially and axially shiftable in these tie-hars and guide bars, and the outer end surfaces of these presser cheeks are supported on a strip or web which interconnects the tie bars.
- This object is achieved, in an apparatus of the type described above, by arranging for the heads of the presser checks to engage one in the other, all axial displacements or axial loads of one of the presser cheeks being transmitted, uniformly and in the same direction, to the other presser cheek, the U-shaped head of one of the presser cheeks being radially shiftably suspended in a hollow member and engaging round a reduced neck portion of the head, which is T-shaped in longitudinal cross-section, of the other presser cheek.
- An important advantage of the apparatus according to the invention resides in the fact that when one of the presser cheeks is forced in a direction tending to move it axially relative to the other presser cheek this attempted" movement is immediately transmitted by reason of the way in which the parts engage one in the other to the other presser cheek. Different surfaces come into mutual contact according to the direction of the particular relative displacement concerned, and the transmission of force or of movement applies to all movements of the different presser cheeks.
- the wall thickness of the presser cheek can, for a given strength, be decreased in this area. This results in a saving in space and, for this reason, it is possible to use a slider wedge having a steeper inclination so that a greater separation of rock may be achieved for a given amount of axial displacement of the slider wedge. Also, the head of the presser cheek which is U-shaped in cross-section enables the slider wedge to be satisfactorily guided.
- the transmission of force takes place in the case of a relative displacement of the presser checks in one direction by way of the intermediate disc, the latter being intentionally inserted with provision for play, so that the slider wedge can be swivelled together with the presser check which straddles it.
- the T-shaped portion of the head abuts against an axially rearwardly offset portion of the end face of the guide sleeve. This dclimits or defines the axial position of the associated presser cheek, because the T-shaped head portion is located or fixed between the intermediate disc and the end face of the guide sleeve.
- the reduced neck portion of the head can abut, by way of a shoulder located at the base of this neck portion, the undersurface of the head of the other presser cheek.
- the two heads of the presser cheeks can, in an extremely simple manner, engage one in the other in a form-locking and forcelocking connection.
- the presser cheek having the T-shaped head may, by means of a lug which lies under this head, about the hollow member, and in this way be radially located or fixed.
- the lug provides a radial reference point, so that the surface of the presser check will always, at the level of the lug, lie at the same radial distance from the hollow member or from the longitudinal axis.
- the slider wedge and the lower portions of the presser cheeks are symmetrically constructed. lt is also possible to give the slider wedge and the presser cheeks an asymmetrical shape.
- An apparatus according to the invention is highly versatile and enables the use of a wide variety of slider wedges and presser checks.
- the presser checks should, conveniently, be so suspended that the resultant of the counteracting forces acting on the presser checks should act, even in the case of asymmetrical loading of the presser cheeks, approximately along the axis of the slider wedge.
- the sliding surface of the presser cheek having a U-shaped head should be given a greater angle of inclination, relative to the longitudinal axis, than the sliding surface of the other presser cheek. Apart from the special shape given to the presser cheeks and to their heads, this results in a better distribution of the operative forces.
- the slider wedge is pivotably secured in the piston rod by means of a transverse pin.
- This transverse pin may, by way of its ends which extend laterally from the slider wedge, engage in elongate holes of the piston rod. It may be envisaged that the elongate holes will, while the slider wedge is being advanced, result in abutment between the piston rod and the slider wedge over a relatively large surface area.
- the apparatus is extremely flexible in use.
- the slider wedge can, by reason of its pivotal form of suspension, be radially shifted, together with the presser cheek which straddles it, for the purpose of withdrawing the other pressure cheek, after it has been suitably turned through an angle of by its head through the arms of the head of the other presser cheek and so withdrawing it from the apparatus.
- the transversee pin lies in an elongate hole, it is possible to effect contact of large surface areas of the end faces of these parts when moving the piston rod and, consequently, the slider wedge outwardly.
- the sides of the transverse pin only engage in the other end face of the elongate hole when the piston rod is, together with the slider wedge, being retraced, i.e., moved inwardly, so that the slider wedge can be returned.
- the underface of the hollow memher is covered off by a resilient impact disc which at least partially surrounds the presser cheeks and continuously holds the latter in contact with the slider wedge. While the resilient impact disc affords mechanical protection for the parts lying within the hollow member, this disc at the same time constitutes a resiliently yielding abutment surface, which always assures a specific starting position or condition.
- the head of the presser cheek having a U-shaped cross-section is supported by way of a widened T-shaped portion by a collar which extends transversely from the hollow member to either side of the head of this presser check.
- the support of the head of this presser cheek on the said collar may be effected by the interposition of a presser disc, acting as a load-bearing part.
- the presser cheeks and/or the slider wedge may have a hard metal lining in their lower contact portions.
- a hard metal lining By reason of the appreciable forces which are entailed in the operation of splitting up rock and by reason of the necessary relative movements between the slider wedge and the presser cheeks large frictional forces are unavoidable in the regions of mutual engagement or contact, even when good lubrication is provided.
- the use of hard metal linings is, inter alia, to be highly recommended, because in this manner the service life of the different parts can be appreciably lenghtened.
- the slider wedge diverges in a plane extending perpendicularly of the plane in which it is tapered. This affords the advantage that, even when there is displacement of the slider wedge relative to the presser cheeks, there will always be sufficient contact between the presser cheeks and the foremost portion of the slider wedge.
- FIG. 1 is a longitudinal cross-section of the slider wedge and presser checks of a rock-breaking apparatus according to the invention
- FIG. 2 is a cross-sectional plan view taken along line ll-II in FIG. I;
- FIG. 3 is a cross-sectional plan view taken along line llllll in FIG. I;
- FIG. 4 is a cross-sectional plan view taken along line IV-IV in FIG. 1;
- FIG. 5 is a cross-sectional plan view taken along line V-V in FIG. 1;
- FIG. 6 is a cross-sectional side elevation taken along line Vl-VI of FIG. I, in which the slider wedge is not shown in cross-section;
- FIG. 7 is a cross-sectional plan view taken along line VII-VII in FIG. 6;
- FIG. 8 is an elcvatlonal view of the two presser cheeks, one of which has been rotated through 90 relative to the other and is in the position which is assumed when the presser checks are being introduced.
- FIG. I The longitudinal cross-sectional view of FIG. I illustrates the lower portion of an apparatus 10, for breaking up or splitting rock, in which a piston rod I2, which is preferably hydraulically actuated, engages with a slider wedge I4.
- This slider wedge engages between two presser cheeks I6 and 18 which project downwardly from within a hollow member 20.
- the presser checks are inserted into a suitable drill hole, whereafter the slider wedge 14 is driven in consequence of the hydraulically generated axial force, between the presser checks.
- the presser checks are forced apart from one another, as a result of which the material surrounding the drill hole is broken up or split.
- the guide sleeve 22 has axially spaced end face portions and an intermediate disc 24 abuts against one of these end face portions and serves to transmit force between the two presser cheeks 16, 18.
- the open end of the hollow member 20 is closed off by a resilient impact disc 26, but as shown in FIG. 6, this opening is defined by two inwardly directed shoulders 50 of the hollow member 2.
- Segment shaped plates 28 which serve as supports for the head 30 of the presser check 18 rest on these shoulders 50.
- the head 30 of presser cheek 18 is U-shaped in cross-section.
- the cross-section of the head 30 has a cross strip 34 and arms or shanks 36 which are attached to both sides of the cross strip 34.
- the arms 36 straddle the slider wedge I4 and also the head 38 of the other presser check 16.
- the head 30 of presser cheek I8 is widened as is clear from FIG. 5 so as to define the cross-bar 40 of a T-shaped portion 32 and the crossbar of the said T-shaped portion is supported on the two plates 28.
- presser cheek I8 is in this way axially located with the provision of only a small degree of play be tween the plates 28 and the intermediate disc 24.
- the head 38 of the other presser cheek I6 is T-shaped in longitudinal cross-section. This head 38 is thus widened in its upper portion to define the cross-bar 40 which is connected to the remainder of the presser cheek I6 by a reduced neck portion 42 and there are shoulders 44 at the junction between the neck portion 42 and the remainder of the presser cheek I6.
- the presser check 18 is moved radially in the Iefthand direction (FIG. 1), whereby free space is created for permitting insertion of the presser cheek I6.
- the presser cheeks l6 and I8 assume their respective positions. as illustrated in FIG. 8, and the cross-bar 40 can, together with the neck portion 42 of the head 38 of presser check 16, be inserted between the arms 36 of the U-shaped head 30 of the presser cheek I8.
- Presser cheek I6 is then turned through so that the shoulders 44 lie under, and abut, the underface of the head 30 of presser cheek I8.
- the cross-bar 40 of the head of the presser cheek I6 lies above the intermediate disc 24, and rests on this disc 24. In this way the heads 30, 38 of the presser cheeks (and, consequently, the main bodies of the presser cheeks themselves) are locked one in the other and are axially located.
- a radially projecting lug 46 of the head 38 of presser cheek I6 abuts, in the assembled condition of the parts, again the hollow member 20.
- presser cheek 16 cannot move radially at this point.
- the arms 36 of the head 30 of the presser check 18 would have to be separated from one another by a greater distance. It is possible, by reason of the relatively small length of the cross-bar 40 of the head 38 of presser cheek 16, to move this cross-bar 40 when the presser cheek 18 has been tilted a sufficient distance and when the presser cheek 16 has been turnedthrough an opening 48 (FIG. 5).
- the slider wedge I4 is of asymmetrical construction, as are also the associated presser cheeks I6 and 18. At its upper end, the slider wedge I4 is connected to the piston rod 12 by means of a transversely extending pin 52 which extends transversely of the longitudinal axis.
- This transverse pin 52 is mounted, with a close fit, in the end portion of the slider wedge 14, and the two laterally projecting parts of the pin 52 engage in co-operating, elongate holes of the piston rod 12.
- the size and arrangement of the elongate holes are selected so that, when the piston rod 12 is being advanced from the cylinder head, the mutually adjacent end faces 54 of the slider wedge 14 and of the piston rod 12 abut one another.
- the lower, sliding contact surfaces of the presser cheeks l6 and 18 and the slider wedge 14 are provided with a hard metal facing 56, to reduce wear. This expedient is necessary on account of the high working pressures and forces which occur in practice.
- presser cheek 18 is shifted in the left-hand direction, as viewed in FIG. 1, when the piston rod 12 is moved outwardly from its associated cylinder. Meanwhile, the presser cheek 16 remains stationary, at least at its upper end, because its lug 46 con tinuously abuts against the hollow member 20. Also, when presser check 16 is being withdrawn for repairing it or replacing it by a thicker presser check 16 the other presser cheek l8 and the slider wedge 14 are radially pushed or tilted in the left-hand direction as viewed in FIG. I.
- Apparatus for mechanically breaking up or splitting rock comprising a hydraulically actuatable pistoncylinder assembly, a slider wedge having inclined surfaces being connected to a piston rod extending from the piston of the piston-cylinder assembly, first and sec- 0nd presser cheeks having interlocking heads and complementary inclined surfaces, and a hollow member connected to the piston-cylinder assembly and surrounding said axially interlocking heads of said first and second presser cheeks disposed on opposite sides of the slider wedge for insertion in a drill hole and lateral separation as a result of sliding movement of said inclined surfaces of the slider wedge over complementary inclined surfacesof the presser cheeks, the head of the first pressure cheek being supported for lateral movement within the hollow member and having a U-shaped axial cross-section with the arms thereof straddling the slider wedge, and the head of the second pressure cheek having a T-shaped longitudinal cross-section with the cross-bar thereof resting on the head of the first pressure cheek and a reduced neck portion which is straddled by the arms of the U-shaped axial crosssection of the head of
- Apparatus as claimed in claim 1 comprising a disc, and a guide sleeve, said disc being inserted at a clearance between the head of said first pressure cheek and a first portion of an end face of a guide sleeve for guiding the piston rod so as to support the cross-bar of the T-shaped longitudinal cross-section of the head of the second presser cheek.
- Apparatus as claimed in claim 1 including shoulders being formed at the base of the reduced neck portion of the 'l shaped longitudinal cross-section of the head of the second presser cheek adapted to abut the underface of the head of the first presser check.
- Apparatus as claimed in claim 1 including a lug being formed below the head of the second presser cheek abutting the hollow member so as to locate the head of the second presser cheek against radially outward displacement.
- Apparatus as claimed in claim 1 comprising a transverse pin pivotally connecting said slider wedge to said piston rod.
- Apparatus as claimed in claim 1 comprising a resilient impact disc partially blanking off the lower end of the hollow member, said resilient impact disc at least partially surrounding the presser cheeks and retaining the presser checks in contact with the slider wedge.
- the head of said first presser cheek having a widened portion which is supported on two inwardly directedshoulders formed on the hollow member.
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Drilling And Exploitation, And Mining Machines And Methods (AREA)
- Earth Drilling (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2336063A DE2336063C2 (de) | 1973-07-16 | 1973-07-16 | Hydraulisch betätigtes Gerät zum mechanischen Zerlegen von Gestein |
Publications (1)
Publication Number | Publication Date |
---|---|
US3894772A true US3894772A (en) | 1975-07-15 |
Family
ID=5887039
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US489032A Expired - Lifetime US3894772A (en) | 1973-07-16 | 1974-07-15 | Hydraulically actuated apparatus for the mechanical splitting of rock |
Country Status (10)
Country | Link |
---|---|
US (1) | US3894772A (fr) |
JP (1) | JPS5342282B2 (fr) |
CA (1) | CA995654A (fr) |
CH (1) | CH578114A5 (fr) |
DE (1) | DE2336063C2 (fr) |
FR (1) | FR2238034B1 (fr) |
GB (1) | GB1433691A (fr) |
IT (1) | IT1013127B (fr) |
SE (1) | SE407176B (fr) |
ZA (1) | ZA743516B (fr) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4252375A (en) * | 1979-09-11 | 1981-02-24 | Edward R. Langfield | Wear or thrust plates for hydraulic rock splitting apparatus |
US4474410A (en) * | 1981-03-31 | 1984-10-02 | Kabushiki Kaisha Komatsu Seisakusho | Power-driven, wedge-operated rock splitter |
US4781418A (en) * | 1987-06-01 | 1988-11-01 | Silvano Pocci | Fluid actuated apparatus for mechanically splitting rock-like material |
US4790602A (en) * | 1987-09-21 | 1988-12-13 | Silvano Pocci | Fluid actuated apparatus for mechanically splitting rock-like material |
US5676427A (en) * | 1994-09-07 | 1997-10-14 | Ha; Jong Su | Apparatus for hydraulically splitting up rock |
WO2006090420A1 (fr) * | 2005-02-24 | 2006-08-31 | Tania Cottini | Outil mecanique pour fendre des roches |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4114951A (en) * | 1977-05-09 | 1978-09-19 | Edward R. Langfield | Hydraulically actuated tool for mechanically splitting rock-like material |
CN104110260A (zh) * | 2014-07-24 | 2014-10-22 | 黑旋风锯业股份有限公司 | 一种矿山荒料开采机 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3558191A (en) * | 1969-01-23 | 1971-01-26 | Fletcher Co H E | Means for applying wedging forces to minerals and other bodies |
US3791698A (en) * | 1971-01-13 | 1974-02-12 | H Darda | Hydraulically operated apparatus for mechanical splitting of rock and the like |
-
1973
- 1973-07-16 DE DE2336063A patent/DE2336063C2/de not_active Expired
-
1974
- 1974-05-08 IT IT50859/74A patent/IT1013127B/it active
- 1974-05-30 CH CH745174A patent/CH578114A5/xx not_active IP Right Cessation
- 1974-06-03 ZA ZA00743516A patent/ZA743516B/xx unknown
- 1974-06-11 SE SE7407665A patent/SE407176B/xx unknown
- 1974-06-14 GB GB2654574A patent/GB1433691A/en not_active Expired
- 1974-06-27 FR FR7422436A patent/FR2238034B1/fr not_active Expired
- 1974-07-15 US US489032A patent/US3894772A/en not_active Expired - Lifetime
- 1974-07-15 CA CA204,829A patent/CA995654A/en not_active Expired
- 1974-07-16 JP JP8161774A patent/JPS5342282B2/ja not_active Expired
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3558191A (en) * | 1969-01-23 | 1971-01-26 | Fletcher Co H E | Means for applying wedging forces to minerals and other bodies |
US3791698A (en) * | 1971-01-13 | 1974-02-12 | H Darda | Hydraulically operated apparatus for mechanical splitting of rock and the like |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4252375A (en) * | 1979-09-11 | 1981-02-24 | Edward R. Langfield | Wear or thrust plates for hydraulic rock splitting apparatus |
US4474410A (en) * | 1981-03-31 | 1984-10-02 | Kabushiki Kaisha Komatsu Seisakusho | Power-driven, wedge-operated rock splitter |
US4781418A (en) * | 1987-06-01 | 1988-11-01 | Silvano Pocci | Fluid actuated apparatus for mechanically splitting rock-like material |
US4790602A (en) * | 1987-09-21 | 1988-12-13 | Silvano Pocci | Fluid actuated apparatus for mechanically splitting rock-like material |
US5676427A (en) * | 1994-09-07 | 1997-10-14 | Ha; Jong Su | Apparatus for hydraulically splitting up rock |
WO2006090420A1 (fr) * | 2005-02-24 | 2006-08-31 | Tania Cottini | Outil mecanique pour fendre des roches |
Also Published As
Publication number | Publication date |
---|---|
JPS5042459A (fr) | 1975-04-17 |
DE2336063C2 (de) | 1975-06-26 |
SE407176B (sv) | 1979-03-19 |
CA995654A (en) | 1976-08-24 |
SE7407665L (sv) | 1975-01-17 |
JPS5342282B2 (fr) | 1978-11-10 |
FR2238034A1 (fr) | 1975-02-14 |
IT1013127B (it) | 1977-03-30 |
FR2238034B1 (fr) | 1982-10-01 |
GB1433691A (en) | 1976-04-28 |
ZA743516B (en) | 1975-05-28 |
DE2336063B1 (de) | 1974-11-14 |
CH578114A5 (fr) | 1976-07-30 |
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