Shearer loader
The redesign of drum shearer with frame elements decouples functional components from the supporting structure, addressing size and maintenance challenges, enhancing operational safety and flexibility in longwall mining.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- EICKHOFF MINING TECHNOLOGY GMBH
- Filing Date
- 2025-11-20
- Publication Date
- 2026-05-28
AI Technical Summary
Conventional drum shearer designs face limitations in size, load-bearing capacity, and maintenance complexity, especially when processing thicker coal seams, requiring larger dimensions and higher electrical power, which complicates maintenance and repair.
The machine body is redesigned with frame elements that decouple functional components from the supporting structure, allowing for modular installation of power and hydraulic distribution units, enabling easier maintenance and adjustment to varying seam thicknesses.
This design enhances operational safety, flexibility, and maintenance efficiency by allowing for higher power density and easier component replacement, adapting to different mining conditions without extensive structural modifications.
Smart Images

Figure EP2025083624_28052026_PF_FP_ABST
Abstract
Description
[0001] ECKH0231
[0002] November 18, 2025
[0003] KN-AC
[0004] drum shearer loader
[0005] The invention relates to a drum shearer loader for longwall mining, comprising a machine body which is movable along a longwall conveyor in the longitudinal direction of the longwall by means of a drive device, at least two drum arms pivotably attached to the machine body, at the free ends of which a cutting drum is rotatably mounted, wherein the machine body has a supporting structure which is formed by a bracing of at least two support elements in the longitudinal direction of the longwall, wherein the machine body comprises functional structural units.
[0006] Such a drum shearer loader is described, for example, in patent application DE 3401707 A1, which discloses a machine body with a tie rod system. This tie rod system makes it possible to clamp the machine body, which is divided into functional units transversely to the longitudinal direction of the machine, so that a load-bearing structure is created and the stability of the assembly is ensured. The housings of the functional units, such as the housing of an electrical power distribution device and a [missing information], serve as load-bearing elements.
[0007] Hydraulic distribution system of the drum shearer. The housings of the individual components are positively connected to each other using pre-assembly screws before the tie rod system is tightened. The functional components are thus an integral part of the supporting structure. This design of the machine body is advantageous because the components can be transported individually to the underground site and then assembled there to form a complete machine body. To withstand the forces and loads that occur, the housings of the components must be correspondingly robust. Each housing is fitted with a cover to provide access to the functional units inside for maintenance and repair. These covers must also be sufficiently sturdy. Furthermore, the covers must seal the housings in accordance with the stringent underground safety requirements, ensuring that the drum shearer is completely explosion-proof.This means, among other things, that on the one hand, any sparking from the respective housing must be prevented, while at the same time, rapid pressure equalization between the housing interior and the environment must be reliably ensured. Accordingly, the housing closure using the covers is quite complex. The flameproof cover is achieved using numerous screws, which in turn must be correspondingly robust. This results in considerable effort during maintenance and repair work. Replacing individual components is not feasible without significant effort. Instead, individual functional units must be removed from their respective housings, repaired, or replaced in a workshop. Overall, the maintenance and repair of these well-known drum shearers are therefore extremely complex.
[0008] Another problem with constructing the supporting structure using the braced housings of the construction units as load-bearing elements is that the overall design of the drum shearer is no longer feasible in this form beyond a certain size. Drum shearers are manufactured in different sizes and can process correspondingly thicker face layers. The applicant, for example, offers drum shearers of various sizes, as shown in its image brochure (EXPERIENCE HAS NO SUBSTITUTE; Eickhoff Bergbautechnik GmbH; 09 / 2017; available at: https: / / www.eickhoff-bochum.de / sites / default / files / field / upload / 2017 09 ukenqlis ch imaqebroschuere berqbautechnik low. pdf; last accessed on
[0009] (November 12, 2024). The largest drum shearer described there can process longwall face thicknesses of up to 8.6 m. This drum shearer weighs up to 250 t and has a total electrical output of 2.8 MW. The machine body of this drum shearer is also formed by bracing the individual structural units in the longitudinal direction of the longwall face using a tie rod system.
[0010] There is now a demand for shearer drums capable of working with face thicknesses of up to 11 meters. However, the conventional structural design of the machine body is reaching its limits. Due to the necessary larger dimensions of the support arms, the machine body must bear higher loads and forces. Furthermore, higher electrical power (over 4 MW) and a larger, usually hydraulic, drive for the drum arms are required. Tests and calculations have shown that this is not possible with the conventional structural design of the machine body. Moreover, maintenance and repair of the shearer drum would become virtually impossible because the size and weight of individual functional units would make transport from the mining site to the workshop impossible.
[0011] The object of the invention is therefore to further develop a drum shearer of the type mentioned above in such a way that the structural design of the machine body allows for a larger drum shearer to be used for processing longwall thicknesses of 10 m and more. In addition, simpler repair and maintenance of the drum shearer should be made possible.
[0012] To solve this problem, the invention proposes, starting from a drum shearer of the type mentioned above, that the supporting elements are designed as frame elements, each of which has installation space for the functional building units.
[0013] According to the invention, the machine body comprises frame elements. These frame elements are clamped by means of tie rods or similar suitable tensioning devices and form the supporting structure of the machine body. The functional components can be accommodated within the installation space of the frame elements, but are decoupled from the supporting structure of the machine body and therefore do not have to absorb any forces that occur during the operation of the drum shearer or that act on the machine body due to the movement of the support arms. The functional components are thus part of the machine body, but not an integral component of the supporting structure. Due to the decoupling of the functional components from the supporting structure, their housings and covers can be designed to be significantly less massive and more easily accessible.
[0014] A further development of the invention provides that the frame elements each have installation areas for a power distribution device and / or a hydraulic distribution device. Each frame element offers specific installation areas for the power and hydraulic distribution units. This separation enables a clear spatial organization of the functional units and ensures better accessibility to the individual units. The clear spatial separation of the power and hydraulic systems not only increases operational safety but also improves ease of maintenance. While known drum shearers use a central electrical power distribution device, it is advantageous in a drum shearer according to the invention to divide the power distribution devices between two functional units.This allows the electrical power, which can exceed 4 MW, to be fed into and distributed across the power distribution units. Consequently, the electrical functional units, such as transformers, frequency converters, etc., can be made smaller. In particular, the housings and covers can be made lighter, resulting in an overall power density (W / kg) up to twice as high compared to the power distribution units of conventional drum shearers.
[0015] Preferably, each frame element can be detachably mounted to a drive unit associated with the drive device. The detachable mounting of the drive units allows for quick disassembly and assembly during maintenance or repairs, thereby increasing machine availability. This enables the replacement of drive units without requiring modifications to the entire machine structure, thus increasing the flexibility and operational efficiency of the drum shearer.
[0016] The drive units can be mounted at different heights on the frame elements, which is particularly advantageous. This height adjustability allows the drum shearer to be adapted to various face thicknesses without requiring extensive modifications to the machine structure. This increases the versatility of the drum shearer, as it can be used for different mining heights, thus enhancing flexibility in longwall mining.
[0017] Furthermore, it is advantageous that an adapter plate is positioned between the frame element and the drive unit. This adapter plate allows the conveyor width (track width) of the drum shearer to be adjusted to the specific requirements. The conveyor width can be adjusted by changing the thickness of the adapter plate. In addition, the adapter plate helps to reduce mechanical stress, which in turn reduces wear on the drive unit.
[0018] A convenient embodiment of the invention provides that each power distribution device is supplied with electrical energy via its own separate electrical supply line. By splitting the supply line, standard cables installed during dismantling can be used. Standard plug connectors can also be used.
[0019] The invention will be explained in more detail below with reference to the drawings. The drawings show:
[0020] Figure 1: schematic representation of a drum shearer loader according to the
[0021] State of the art in 3D view;
[0022] Figure 2: schematic representation of a drum shearer loader according to the
[0023] Invention in an exemplary embodiment in a side view from the offset side; Figure 3: schematically a frame element of a drum shearer according to the invention in a 3D view;
[0024] Figure 4: schematic of an electric
[0025] Energy distribution device of a drum shearer loader according to the invention in a 3D view;
[0026] Figure 5: schematically a drive device of a drum shearer loader according to the invention in a 3D view;
[0027] Figure 6a-c: schematically a drive unit of a drum shearer loader according to the invention, which is arranged in three different positions on a frame element, in 3D views.
[0028] Figure 1 shows a drum shearer known from the prior art. The drum shearer has a machine body 1, which is divided into individual functional units 2. The supporting structure of the machine body 1 is formed by the housings of the functional units 2 as support elements 3. The support elements 3 are braced in the longitudinal direction S of the face by means of a tie rod system (not shown). Furthermore, the drum shearer has two drum arms 4, which are pivotably attached to the machine body 1. Cutting drums 5 are arranged at the ends of each drum arm 4. In addition, a drive device with two drive units 6 is arranged on the machine body 1. The drum shearer is moved along a face conveyor 7 by means of the drive units 6.
[0029] The housings of the functional units 2, acting as load-bearing elements 3 and braced by the tie-rod system, form the supporting structure of the machine body 1 and must therefore be able to absorb the loads and forces acting on the machine body 1 during operation of the drum shearer. As described above, this design concept reaches its limits with increasing size and power of the drum shearer due to spatial and safety restrictions underground.
[0030] Therefore, according to the teaching of the present invention, the drum shearer loader has a completely different design concept for the machine body, which is explained in more detail below with reference to Figures 2-6.
[0031] Figure 2 shows a drum shearer according to the invention in a side view from the offset side. According to the invention, the machine body 1 comprises support elements 3 in the form of two frame elements 8. The two frame elements 8 are braced against each other in the longitudinal direction S of the struts by means of a tie rod system (not shown). Alternatively, other bracing means can be used instead of the tie rod system used here. The frame elements 8 have an installation space 9 inside. The functional components 2 are arranged in the installation space 9. In this view, a power distribution device 10 is arranged in each of the two frame elements 9. In addition, a hydraulic distribution device (not shown here) is arranged in the installation space 9 of each of the frame elements 8. Finally, drive units 6, which are arranged on the frame elements 8, are shown.
[0032] The individual components of the machine body 1 and their conceptual arrangement will be discussed in more detail below.
[0033] Figure 3 shows a single frame element 8 in an offset-side 3D view from a top-down oblique angle. The frame element 8 has an installation space 9, which is divided into a first installation area 9a and a second installation area 9b. The first installation area 9a serves to accommodate the power distribution device 10 (see Figure 4) and the hydraulic distribution device. The second installation area 9b is used to accommodate parts of the drive unit (see Figure 6). Holes 11a are provided on the outer surface of the frame element 8 to attach the drive unit 6 to the frame element 8. In this embodiment, one frame element 8 weighs 18 t. The two frame elements 8 that form the supporting structure of the machine body 1 thus have a combined weight of 36 t. Maintenance of the functional components 2 (see Figure 2) can be carried out via the offset-side and top-side open areas of the frame element 8.Finally, the frame element has bores 11 a, which serve to attach the drive unit (see Figure 6a-c).
[0034] Figure 4 shows an electrical power distribution device 10 in an offset 3D view from an oblique top angle. The functional units of the electrical power distribution devices 10 are each arranged in housings 10a, which are each sealed with covers 10b using screw connections to prevent fire-resistant sealing. The power distribution device 10 is installed in the installation area 9a in the frame element 8 (see Figures 2 and 3). The electrical power is supplied via a plug connection 12. Unlike conventional design concepts, the covers 10b and housings 10a of the electrical power supply unit 10 are not an integral part of the load-bearing structure of the machine body 1. The load-bearing structure is formed solely by the frame elements 8. Accordingly, the housings 10a and covers 10b can be made less massive. Fewer screws are also required to close the housings 10a with the covers 10b.Overall, the energy distribution device 10 achieves up to twice the power density (W / kg) compared to conventional energy distribution devices. Maintenance and repair are also less complex due to the lower weight of the components and the reduced number of screw connections.
[0035] Figure 5 shows a drive unit 6. The drive unit 6 has a modular design comprising a wheel housing gearbox 6a, a winch gearbox 6b, and a traction motor 6c. The drive unit is also provided with bores 11b, which correspond to the bores 11a on the frame element 8. The winch gearbox 6b is driven by the traction motor 6c. The force is transmitted via the winch gearbox 6b to the wheel housing gearbox 6a and finally, via a pinion gear (the last gear in the wheel housing gearbox, not shown), to a pinion. Each of the two drive units 6 has a tractive force of 1010 kN. The train speed is between 13 and 27 m / min.
[0036] Figures 6a-c show the drive unit 6, which is arranged in three different positions on the frame element 8. The winch gearbox 6b is located in the installation area 9b within the frame element 8 and is not visible from this perspective. Due to its arrangement in the installation area 9b of the frame element 8, the winch gearbox 6b is not part of the load-bearing structure of the machine body 1. Therefore, the winch gearbox 6b can be made significantly lighter overall. While the winch gearbox in a conventional shearer of similar size weighs 14 t, the winch gearbox 6b in the shearer according to the invention weighs only 4 t.
[0037] As shown in Figure 6b, the drive unit 6 can be arranged at different heights (H, H+H') on the frame element 8. For this purpose, the drive unit 6 is fixed at the desired height on the frame element by means of screw connections through the corresponding bores 11a, 11b. The height difference H' between the arrangement in Figure 6a and Figure 6b is 500 mm in this embodiment. A cover plate 13 is attached to the frame element 8 above the drive unit 6. This serves to protect the interior area 9b from dirt. The conveying height of the drum shearer can be adjusted via the height adjustment.
[0038] Figure 6c shows an additional adapter plate 14 between the winch gearbox 6b and the wheel housing gearbox 6a. The adapter plate 14 allows the conveying width of the drum shearer to be increased. In this example, the extension X' is 200 mm. Reference numeral list:
[0039] 1 Machine body
[0040] 2 functional building unit 3 load-bearing element
[0041] 4 roller arm
[0042] 5 cutting roller
[0043] 6 Drive unit
[0044] 6a Winch gearbox 6b Wheel arch gearbox
[0045] 7 longwall conveyors
[0046] 8 frame element
[0047] 9 Installation space
[0048] 9a, 9b Installation area 10 Electrical power distribution device
[0049] 11a,11b Drill holes
[0050] 12 Plug connection 13 Cover plate
[0051] 14 Adapter plate
[0052] S strut longitudinal direction
[0053] H height
Claims
Patent claims 1. Drum shearer loader for longwall mining, comprising a machine body (1) which is movable along a longwall conveyor (7) in the longitudinal direction (S) of the longwall by means of a drive device, at least two drum arms (4) pivotably attached to the machine body (1), at the free ends of which a cutting drum (5) is rotatably mounted, wherein the machine body (1) has a supporting structure which is formed by a bracing of at least two support elements (3) in the longitudinal direction (S) of the longwall, wherein the machine body (1) comprises functional building units (2), characterized in that the support elements (3) are designed as frame elements (8) which each have installation space (9) for the functional building units (2).
2. Drum shearer loader according to claim 1, characterized in that the frame elements (8) each have installation areas (9a) for a power distribution device (10) and / or a hydraulic distribution device.
3. Drum shearer loader according to one of the preceding claims, characterized in that a drive unit (6) associated with the drive device is detachably attached to each of the frame elements (8).
4. Drum shearer loader according to claim 3, characterized in that the drive units (6) can be attached to the frame elements (8) at different heights (H, H+H').
5. Drum shearer loader according to claim 3 or 4, characterized in that between frame element (8) and A drive unit (6) is arranged with an adapter plate (14).
6. Drum shearer loader according to one of claims 2-5, characterized in that the energy distribution devices (10) are each supplied via their own electrical supply line.
Citation Information
Patent Citations
Long wall face-cutting machine for mining
DE4410133A1
Shearer loader for underground mining with bearing units within mainframe
WO2015117729A1