The invention relates to a device for milling treatment, in particular, rock or other materials, with a spindle drum which is rotatably mounted on a drum support about a drum axis, in which a plurality of tool spindles are supported eccentrically to the drum axis to be rotatably drivable about spindle axes and carry machining tools at their ends projecting from the spindle drum. The invention further relates to a method for milling rock or the like using such a device.
For the milling of rock or other hard materials as for example of extraction products in underground or open-work mining, of tarmac or concrete components in road or structural engineering, a plurality of milling systems are known, which are mainly rotary driven drums or discs, at the circumference of which are mounted milling tools, for example round shaft bits, in an evenly distributed manner. If rock or coal is extracted in underground mining with such a drum provided with milling tools at its circumference, for example with the help of a drum shearer loader, and the cutting disk or drum cuts or mills the material to be extracted with a full face cut, approximately half of all machining tools arranged at the circumference of the drum are engaged simultaneously. Each machining tool is engaged with the material to be machined during the full face cut via half a rotation, that is 180°, which results in that the hard metal tips of the tools are heated to very high temperatures and wear quickly, especially in harder materials.
A further disadvantage with the known machines consists in that the entire contact pressure, with which the drum abuts against the rock, is distributed onto a large number of individual tools, so that for every individual chisel in use, only a comparatively small pressure force is available. If the entire pressure of the drum against the rock is for example about 2000 N, and about 20 individual tools are always used during a full cut, on the average every individual tool has only a contact pressure of 100 N. Furthermore, it is also difficult to axially drive into the material to be machined with the known devices, in which the tools are drivingly connected at the circumference of a roller or a drum, which problem can be attributed to the fact that the optimum cutting speed is at the outer diameter of the drums, and that the cutting speed is consistently reduced in the direction towards the axis of rotation of the drum or the roller, and becomes so small in the proximity of the axis of rotation, that cutting is practically impossible there. Even when the drum is provided with tools at its face side, these cannot break out the rock abutting their face during the axial driving-in of the drum in a reasonable manner.
From DE 34 45 492 C2, a boring head for boring in rock is known, which comprises a tool support with boring tools, which is mounted on a central shaft, which is coupled to bore rods extending between the bore hole and the boring head. The boring tools at the tool support can be rotatably driven via a planetary gear transmission.
It is the object of the invention to create a device for the milling treatment of rock or other materials of the above-mentioned type, which is able to also treat very hard materials with a high milling performance, whereas, compared to conventionally driven tools, the pressing forces exerted by the spindle drum are reduced and the edge lives of the tools are extended. Particularly, the device according to invention shall have a high operational security, be compact and offer the possibility to receive machining tools of different types as for example milling rollers, saw blades, undercutting tools or the like with arbitrary weights and sizes.
This object is being solved with the invention with the features as defined in the independent claims. As at least two of the tool spindles can be driven by a common transmission gear drive, which comprises driven gear wheels drivingly connected to the tool spindles and a common drive element, in particular a drive gear wheel or also a drive chain, a drive transmission belt or the like, which drive element cooperates with the driven gear wheels, while the drive element and the spindle drum can be rotated relatively to one another, a particularly compact arrangement of a device is created, in which the at least two tool spindles with the tools thereon are driven synchronously outside the centre axis of the spindle drum. The machining tools arranged at the tool spindles can thereby be adjusted easily so that even during a full cut with an abutment of 180° respectively only one machining tool or only a few tools are used simultaneously, so that the entire available pressing force of the spindle drum can respectively only be used by one or a few tools, that is, the individual tool presently in engagement with the rock has a very high loosening force.
It is possible that the spindle drum comprises a rotary drive, which is decoupled from the transmission gear drive. In this embodiment, the spindle drum is thus rotated by a rotary drive and the tool spindles experience their drive independently of the rotary speed of the spindle drum. With this embodiment, it is even feasible to stop the spindle drum in any case briefly during the axial drive-in of the device into the rock and to bore a short distance into the rock only by rotation of the tool spindles, and only then to start the drive for the spindle drum.
It has proved to be particularly advantageous if the spindle drum and at least some of the tool spindles have a common rotary drive, so that, with a rotation of the spindle drum, the tool spindles which are also acted upon by the common rotary drive are also automatically rotated.
In this context, it is constructionally advantageous if the drive element formed from a drive gear wheel is arranged irrotationally with respect to the drum support, in particular firmly connected to the drum support. The driven gear wheels drivingly connected to the tool spindles then mesh with the drive gear wheel arranged irrotationally with respect to the drum support, whereby the tool spindles are rotated when the spindle drum in which the tool spindles are received is driven by the rotary drive. Very high forces and torques can be transferred with such a planetary gear drive with a particularly compact design.
The tool spindles are preferably received in bearing bushes by means of bearings in a rotary manner and are conveniently sealed by shaft seals. It is particularly advantageous with such an arrangement, if the bearing bushes with the tool spindles mounted therein in a rotary manner are inserted and locked in an exchangeable manner like cartridges in drum chambers provided at the spindle drum. The tool spindles can then be replaced with their bearings and possibly seals by simple exchange of the bearing bushes in the structural unit, for example when they are worn or when tool spindles for other machining tools are to be used. The tool spindles in the bearing bushes are pre-mounted, so that removal and fitting of this structural unit only takes a very short time.
Preferably, all tool spindles can be drivable via the common drive gear wheel of the transmission gear drive. However, it is also easily possible that a first group of tool spindles is drivable via a first common drive gear wheel and a second group of tool spindles is drivable via a second common drive gear wheel, for example in a case in which a first group of tool spindles is arranged at the spindle drum on a pitch circle having a larger diameter and a second group of tool spindles is arranged on a pitch circle having a smaller diameter. The gear transmission ratios between the tool spindles of the first group and the first drive gear wheel and the tool spindles of the second group and the second drive gear wheel and/or the directions of rotation of the tool spindles of the first and second group can then be different. As already suggested above, the tool spindles of the first group and those of the second group can be arranged with a different radial distance from the drum axis in the spindle drum, that is, on two different pitch circles.
The tool spindles are preferably arranged uniformly distributed over the circumference in the spindle drum.
In a particularly advantageous embodiment of the device according to invention it is possible that the machining tool(s) of one tool spindle is/are arranged in an offset manner relative to the arrangement of the machining tool(s) of the tool spindle being arranged in front or behind that one tool spindle in the drum circumference direction. In other words, the machining tools of tool spindles following each other in the circumferential direction of the spindle drum can be arranged with regard to one another in a phase-shift manner. This arrangement makes it possible to ensure in a particularly advantageous manner during the execution of the method according to the invention for milling of rock, that an individual tool arranged at a tool spindle reaches engagement with the rock to be machined at another point than an individual tool of a tool spindle lying in front of it in the direction of rotation. It is thus ensured by the phase-shifted arrangement of the tools that the impact points of the individual tools or cutters of the different tool spindles do not overlap, but that a following tool machines the rock at a point which the tools of a tool spindle moved previously through the rock have left. Thereby a particularly effective treatment of the rock or the like is achieved. In order to achieve the desired phase shift or the offset angle as exactly as possible, the machining tools are preferably arranged in an adjustable manner at the tool spindles, that is, they can be adjusted in their angular position relative to the tool spindles.
The machining tools can comprise one or several machining bits or individual tools at every tool spindle. In a particularly advantageous embodiment of the invention, at least some of the individual tools can consist of straight shank bits, while in some cases, flat chisel tools or roller bits have proved themselves, in particular roller bits which are formed conically on one side. For many machining uses it has proved to be advantageous if the machining tools project at the most with 50% of their machining surfaces radially over the outer circumference, that is, that at the most half of the individual machining tools of a tool spindle are in simultaneous engagement with the rock or the like.
The spindle drum can be provided with a preferably centrically arranged dust extraction opening, through which the fine dust which results during the milling treatment of the rock or the like can be extracted. It is also advantageous, if the device is provided with at least one sprinkling device for the machining tools, with which on the one hand the resulting dust can be bound by water sprayed on the machining point, and on the other hand, a cooling of the machining tools can be provided. The sprinkling device is preferably arranged at the spindle drum and/or at the drum support.
With the device according to invention, machining tools of different types can be used. It is thus possible, when the machining tools of one or several of the tool spindles essentially consist of a chisel support and several round bits, flat bits and/or roller chisels arranged thereon, whereas the arrangement is in such a manner that the chisel/bit tools arranged at the chisel support machine the rock or other respectively machined material in an undercutting manner in one or more layers. The arrangement is preferably made in such a manner that a tool operating in several layers tapers in the direction of the rock to be machined, preferably in the form of steps. The machining tools can essentially also consist of milling rollers, which are arranged on one or several tool spindles. These milling rollers can be formed cylindrically or can taper conically or expand towards the rock to be machined.
If the drive element consists of a drive gear wheel geared on the outside, which is connected to the drum support, the direction of rotation of the tool spindles is the same as the one of the spindle drum. If the drive element consists of a drive gear wheel geared on the inside, the tool spindles driven from such a drive gear ring rotate in the opposite direction of the spindle drum.
In order to provide the rotary drive for the spindle drum independent from the transmission gear drive for the tool spindles, a constructional embodiment has proven to be advantageous, in which the spindle drum comprises a reception bore for a drive shaft running coaxially to the drum axis, which drive shaft is rotatably supported in the reception bore and is coupled to the drive element for the tool spindle. The drive shaft is thus mounted rotatably concentrically in the spindle drum, which is not only particularly compact, but which also ensures a high stability of the construction. The spindle drum can comprise a closed housing with an approximately cup-shaped drum base and a housing lid, so that the drive element, that is, in particular the drive gear wheel, is received in the inside of the drum base and is connected to the drive shaft and is covered by the housing lid.
The transmission drive for the tool spindles is preferably arranged in an encapsulated manner in the spindle drum. The machining tools with their respective tool spindles can be in an overhung position at the spindle and can project from the spindle drum at the face and/or at the circumference.
So as to favour the axial driving-in of the device into the rock, it has been proved to be advantageous if the spindle drum is, additionally to the tool spindles which are arranged distributed over its circumference, provided with milling tools with a core milling cutter arranged in the inside of the pitch circle described by the tool spindles, which core milling cutter is preferably arranged with a small eccentricity to the drum axis. With the help of the core milling cutter which is formed in a driveable manner, it can be ensured that the entire rock present in front of the face of the spindle drum will be milled during the axial feed motion of the device therein.
In order to ensure a particularly stable reception of the tool spindles, the machining tools with their respective tool spindles are preferably mounted at the spindle drum by means of a two-point bearing. A fixed floating bearing can be provided for this, alternatively, an engaged bearing, in particular in the X-arrangement can be used, for example by means of taper roller bearings or the like.
Especially in cases where machining tools with a comparatively large axial length are to be used, for example tools with long milling shanks, it is particularly advantageous if the spindle drum comprises an approximately plate-like bearing flange in the proximity of the drum support for the reception of the first bearings of the tool spindles and a support journal projecting concentrically to the drum axis, at which at least one support element for the reception of the second bearings of the tool spindles is arranged. The regions of the machining tools which machine the rock are then between the two bearings, so that a particularly sturdy support is achieved. With this embodiment of the invention it can further be convenient, that the support element or the support journal comprises a bearing journal arranged concentrically to the spindle drum axis for the additional support of the spindle drum. Thereby it is then possible to also mount the spindle drum itself by means of a two-point bearing, that is to additionally support it at the end which is turned away from the drum support, and therewith to avoid bending which can occur with long tools and an overhung bearing.
The support element can consist of a lid flange arranged at the face of the support journal, which flange is provided with bearing receptions for the second bearing. The machining tools are then covered by the lid flange at their face and machine the rock only with individual tools which are arranged at their circumference and which project radially between the plate-like bearing flange and the lid flange of the spindle drum therefrom. It is also possible that at least two support elements are provided, which are arranged at different distances from the bearing flange and which respectively receive the second bearings of different tool spindles. With this arrangement, the second bearings of the tool spindles then have a distance from the face (free) end of the machining tools, which can then also be in engagement with the rock with their faces.
So as to avoid damages of the device by overloading, it has proved to be convenient that the drive element is connected to the drum support via an overload clutch, which can for example be a spring-loaded friction clutch. The spring load acting on the clutch is preferably adjustable, so that the activation value at which the clutch is released and the drive element slips through at the drum support can be adjusted.
The spindle drum can, at its rear side, which is turned away from the machining tools, be provided with a demountable covering cap sealed with regard to the drum support by means of a shaft seal, which cap enables access to the transmission gear drive and other parts lying below, which have to be serviced or inspected occasionally.
Generally, the tool spindle axes in the spindle drum will be aligned parallel to the drum axis. It is however also possible to arrange the tool spindle axes in an inclined manner relative to the drum axis, whereby the milling result can be improved further with some rocks or materials to be machined. In a further embodiment of the invention, every machining tool preferably comprises several individual tools arranged evenly over the circumference of the machining tool, and is mounted to the associated tool spindle using a detent coupling, whereby the number of possible lock positions of the detent coupling is adapted to the number at the machining tool so that these are in the same relative position to the tool spindle in every locked position. The detent coupling responds when the machining tool is blocked by the rock which it engages, so that the associated tool spindle which carries this tool can rotate further to the next lock position, into which the machining tool then locks again and rotates further. The machining tool thereby locks again in such a position where its relative position to the machining tools of adjacent tool spindles remains the same, that is, the originally adjusted phase shift or the offset of the machining tools of successive tool spindles remains after the response of the detent coupling and locking of the tool.
The device according to invention and the method that can be effected thereby are particularly suitable for the removal of mineral extraction products as for example coal, ore rock or the like. The device can be used for this purpose as replacement for a well-known cutting head of a drum shearing machine or as cutting head of a selective cut or full cu heading machine. The device and the method can advantageously also be used for the machining of concreted or tarmacked surfaces or buildings, for example when milling tarmacked or concreted road surfaces, during demolition of concrete buildings or the like. It is often advantageous for the different applications if the device according to the invention is mounted to an adjustable arm and is engaged with this against the rock or the like to be machined. Use of the device according to the invention is also conceivable with small appliances, for example with hand-held plaster milling devices.
Further characteristics or advantages of the invention result from the following description and the drawings, where preferential embodiments of the invention are explained further with examples. It shows:
The various embodiments of the device according to the invention shown in the drawings, which device is designated as 10 in its entirety, serve for the milling of rock, for example mineral extraction products such as coal or ore, or also for the processing of concrete, tarmac or other building materials, for example during the milling of road surfaces or the like. As far as the different embodiments of the device according to the invention conform in their constructional details, a repeated description of these recurring details with different embodiments shall be forgone. Rather, after the detailed description of the fundamental construction on the basis of
Referring to
The bearing journal 14 changes into a circular plate-like bearing flange 18 of the spindle drum at its other end opposite the drive wheel 17, which journal comprises several, in the example of the embodiment six, evenly distributed drum chambers 20 on a pitch circle 19 near its outer circumference. The drum chambers 20 each receive a bearing bush 21 with a tool spindle 22 mounted rotatably therein, whereby the bearing bushes with the tool spindles mounted therein like a cartridge are inserted into their respective drum chamber 20 in an exchangeable manner and are locked in the inserted state by means of fixing screws 23. At their rear end, with which the tool spindles project rearwardly from the bearing flange 18 of the spindle drum, they are provided with driven gear wheels 24 which mesh with a driving gear wheel 25, which is secured firmly to the drum support 11 with screws 27 at a gear wheel reception 26 provided for this. One can see in the first embodiment shown in
For the attachment of the entire device 10 to a machine frame (not shown) provided for this, as for example an arm of a drum shearing machine or a road milling machine, mounting holes 28 for fixing screws are provided at the drum support 11, which screws are threaded through access holes 29 provided in the bearing flange 18 of the spindle drum and can be screwed into threaded bores at the machine frame aligned with the mounting holes 28 by means of a suitable tool as for example an allen key. The entire device can be quickly installed at the machine frame without disassembly of any parts of the device.
In
The front ends of the tool spindles projecting from the free side of the spindle drum form cone seat receptions 33 for machining tools, different designs of which being shown in
With the embodiment of the invention shown in
The drive shaft is provided with a front gear wheel 39 at its rear end, which can be coupled to a spindle drive motor (not shown), so as to rotate the drive shaft 36 and thus the drive gear wheel 25 mounted thereon on the inside of the spindle drum and to hereby effect the rotary drive of the tool spindles, so that the number of revolutions of the tool spindles can be adjusted independently of the number of revolutions of the spindle drum.
In the embodiment according to
With the example of an embodiment according to
With embodiment shown in
In
A further embodiment of the device according to the invention is shown in
The embodiment of the device according to the invention shown in
With the embodiment shown in
With the embodiment of the device according to the invention according to
With the embodiments of the device according to the invention described up to now with a common drive for the spindle drum and the tool spindles mounted rotatably therein, the direction of rotation of the spindle drum and the tool spindles was the same.
With the embodiments shown in
Finally, with the embodiment shown in
The invention is not limited to the shown and described examples of embodiments, but different changes and additions are feasible, without leaving the scope of the invention. It is for example possible to let the tool spindles of a first group of tools and the tool spindles of a second group of tools rotate in opposite directions, in particular when the tools of the first group are provided on a different pitch circle to those of the second group. The details shown and described on the basis of the individual embodiments can be combined with one another in most diverse ways, which can be noted by the expert without special difficulties. With the selection of suitable machining tools it is easily possible, to use the device according to the invention also for the machining of other materials than rock or coal, for example for the machining of metal, wood or plastics.
Number | Date | Country | Kind |
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10 2005 003 840 | Jan 2005 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2006/000683 | 1/26/2006 | WO | 00 | 7/19/2007 |
Publishing Document | Publishing Date | Country | Kind |
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WO2006/079536 | 8/3/2006 | WO | A |
Number | Name | Date | Kind |
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3412816 | Lautsch | Nov 1968 | A |
4436345 | Silks et al. | Mar 1984 | A |
4548443 | Turner | Oct 1985 | A |
4627501 | Ebeling | Dec 1986 | A |
5253925 | Modzik, Jr. | Oct 1993 | A |
6764141 | O'Neill | Jul 2004 | B2 |
Number | Date | Country |
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34 45 492 | Aug 1985 | DE |
2 018 861 | Oct 1979 | GB |
Number | Date | Country | |
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20080116734 A1 | May 2008 | US |