Drive device for vertical mill

Abstract

The invention relates to a drive device (10) comprising: a main housing (12) defining an internal space (40); a rotating plate (14) rotatable relative to the main housing; an axial bearing (16) fixed to the main housing; an output gear (18) fixed to the rotating plate; a drive pinion (20) meshing with the output gear (18); a drive unit (22) capable of rotating at least one drive pinion; and a lubrication unit (24) capable of injecting a lubricant under pressure between the rotating plate and the axial bearing. The internal space (40) includes a compartment (70) located below the axial bearing, said compartment being configured (66) to receive by gravity the lubricant injected by the lubrication unit between the rotating plate and the axial bearing.

Description

[0001] The present invention relates to a drive device for a vertical roller mill, of the Vertical Roller Mill (VRM) type.More specifically, the invention relates to a drive device of the type comprising: a main casing defining an internal space; a rotary plate movable in rotation relative to the main casing, around a first vertical axis; said rotary plate being fixed or capable of being fixed to a rotary grinding table of the vertical roller mill; an axial bearing secured to the main casing, the rotary plate being arranged in vertical support on said axial bearing; an output toothed ring, secured to the rotary plate; at least one drive pinion meshing or capable of meshing with the output toothed ring, the at least one drive pinion being movable in rotation around a second axis; at least one drive unit, capable of rotating the at least one drive pinion; and a first lubrication unit, capable of injecting under pressure a first lubricant product between the rotary plate and the axial bearing.

[0002] VRM type mills are used in the cement industry for grinding clinker, coal and also for the preparation of raw materials. A mill comprising a drive device of the aforementioned type is described in particular in document US7926754.

[0003] The rotation of the grinding table requires the injection of pressurized oil by the first lubrication unit, between the table and the axial bearing. This operation creates an oil film allowing the rotation of the table relative to the main housing. The first lubrication unit is generally located below the grinding table, in order to take advantage of the natural flow of oil to recover it.

[0004] In known devices, the installation of lubrication units requires the creation of one or more pits in the structure supporting the crusher and its drive device. The creation of these pits is all the more restrictive as they are generally arranged in restricted spaces and they make the civil engineering operations necessary for the installation of the drive device more difficult. A drive device for a known crusher is described in document US6347757 B1.

[0005] The present invention aims to facilitate the installation of the first lubrication unit of the vertical roller mill. To this end, the invention relates to a drive device of the aforementioned type, in which the internal space of the main casing comprises a first compartment arranged under the axial bearing, said first compartment being configured to receive by gravity the first lubricating product injected by the first lubrication unit between the rotary plate and the axial bearing.

[0006] According to other advantageous aspects of the invention, the training device comprises one or more of the following characteristics, taken individually or in all technically possible combinations: the first lubrication unit comprises: a first pump; and a first pipe for injecting the first lubricating product, the first injection pipe connecting the first pump to the axial bearing, the first injection pipe being received in the internal space of the main casing; the first pump is received in the internal space of the main casing; the first pump is arranged outside the internal space; the drive device further comprises: a pinion casing enclosing the at least one drive pinion; and at least one second lubrication unit capable of injecting a second lubricating product into the pinion casing; the at least one second lubrication unit comprises a second pump and at least one second pipe for injecting or recovering the second lubricating product, the second injection pipe and / or the recovery pipe connecting the second pump to the pinion casing;the at least one second injection or recovery pipe is received in the internal space of the main casing; the at least one second injection or recovery pipe is arranged outside the internal space, the drive device comprising a secondary casing attached to the main casing and receiving said second injection or recovery pipe; the at least one second lubrication unit is capable of injecting the second lubricating product into the at least one drive unit.;

[0007] The invention further relates to a vertical roller mill comprising a grinding table and mill rollers capable of rolling on the table, said mill comprising a drive device as described above, the rotary plate of said drive device being fixed to the grinding table.

[0008] The invention will be better understood on reading the description which follows, given solely as a non-limiting example and made with reference to the drawings in which: [ Fig 1 ] there figure 1 represents a schematic view, in section, of a drive device according to a first embodiment of the invention; [ Fig 2 ] there figure 2 represents a schematic view, in section, of a drive device according to a second embodiment of the invention; and [ Fig 3 ] there figure 3 represents a schematic perspective view of a training device according to a third embodiment of the invention.

[0009] Each of the figures 1 , 2 And 3 represents a drive device, respectively 10, 110 and 210. Preferably, each of said drive devices 10, 110, 210 is part of a vertical roller mill, respectively 11, 111 and 211.

[0010] In addition to the corresponding drive device 10, 110, 210, each vertical roller mill 11, 111, 211 comprises a rotating grinding table (not shown) and grinding rollers (not shown). The rollers are adapted to roll on the table to crush material to be ground, such as clinker, coal or ore, as described in US7926754.

[0011] In the following description, the drive devices 10, 110 and 210 will be described simultaneously, the common elements being designated by the same reference numbers.

[0012] The drive device 10, 110 and 210 comprises: a main housing 12, 112, 212; a rotary plate 14; an axial bearing 16; an output toothed ring 18; at least one drive pinion 20; at least one drive unit 22; a first lubrication unit 24, 124, 224; and at least one second lubrication unit 26, 126, 226.

[0013] The main casing 12, 112, 212 extends along a first vertical axis 30 and comprises an upper casing 32 and a lower casing 34, 134, 234. Said upper casing 32 and lower casing 34, 134, 234 are arranged one above the other and separated by a substantially horizontal partition 35.

[0014] The upper casing 32 preferably has a shape of revolution relative to the first axis 30.

[0015] The lower casing, or support 34, 134, 234, comprises a substantially planar base 36 and a cylindrical wall 38. Said cylindrical wall 38 extends along the first vertical axis 30 from said base 36. The base 36 forms a radial projection, for example in the form of a crown, relative to the cylindrical wall 38.

[0016] The partition 35, the base 36 and the cylindrical wall 38 define an internal space 40 of the support 34, 134, 234. A hatch 42 is optionally provided in the cylindrical wall 38 to provide access to said internal space 40.

[0017] The base 36 is placed on a foundation 44, for example the floor of a room receiving the vertical roller mill.

[0018] The main casing 12, 112, 212 will be described in more detail below.

[0019] The rotary plate 14 is movable in rotation around the first axis 30 relative to the main casing 12, 112, 212. Said rotary plate 14 is received in the upper casing 32.

[0020] The rotary table 14 is fixed to the grinding table (not shown) of the vertical roller mill 11, 111, 211.

[0021] The axial bearing 16 is integral with the upper casing 32. The rotary plate 14 bears vertically on the axial bearing 16. Said axial bearing is thus able to take up the weight of the grinding table via the rotary plate 14, and to transmit this weight to the main casing 12, 112, 212. Similarly, the axial bearing 16 is able to take up the axial forces generated by the grinding process.

[0022] Preferably, the axial bearing 16 is a hydrostatic pad bearing or a hydrodynamic pad bearing.

[0023] Preferably, the drive device 10, 110, 210 further comprises a radial bearing 46 secured to the upper casing 32. The radial bearing 46, for example a radial rolling bearing, is capable of absorbing the radial forces generated by the grinding process.

[0024] The output toothed crown 18 is integral with the rotary plate 14. Preferably, the toothed crown 18 has external teeth, as shown in the figures 1 , 2 And 3 . According to an alternative embodiment, the toothed crown has internal teeth. The toothed crown 18 has straight teeth or helical teeth.

[0025] The at least one drive pinion 20 is capable of meshing with the output ring gear 18. Preferably, the device 10, 110, 210 comprises several drive pinions, distributed angularly in a regular or irregular manner around the first axis 30 and the ring gear 18.

[0026] The or each drive pinion 20 is rotatable around a second vertical axis 50, distinct from the first axis 30.

[0027] Preferably, the device 10, 110, 210 comprises at least one pinion casing 51. The or each pinion casing 51 is fixed to the upper casing 32 and contains at least one drive pinion 20.

[0028] The at least one drive unit 22 is capable of driving the at least one drive pinion 20 in rotation. According to one embodiment, the device 10, 110, 210 comprises several drive units, each of said units being capable of driving one or more drive pinions 20 in rotation.

[0029] The or each drive unit 22 comprises a rotary motor 52 and a reducer 54. Said reducer 54 comprises a reducer housing 56, an input shaft 58 connected to the motor 52 and at least one output shaft 60. Said output shaft 60 is connected to the drive pinion 20, so as to drive said pinion in rotation about the second vertical axis 50.

[0030] Preferably, the casing 56 of the reducer 54 of the or each drive unit 22 is fixed on the base 36 of the main casing 12, 112, 212, around the cylindrical wall 38. Alternatively, the casing 56 is fixed on the cylindrical wall 38. The motor 52 is arranged on the base 44.

[0031] The first lubrication unit 24, 124, 224 of the drive device 10, 110, 210 is capable of injecting under pressure a first lubricating product, such as an oil, between the axial bearing 16 and the rotary plate 14.

[0032] The first lubrication unit 24, 124, 224 comprises in particular a first pump 62 and a first injection pipe 64. The first injection pipe 64 connects the first pump 62 and the upper casing 32, so as to bring the first lubricating product between the axial bearing 16 and the rotary plate 14.

[0033] Furthermore, the partition 35 of the main casing 12, 112, 212 comprises a flow opening 66; and the internal space 40 of the support 34, 134, 234 comprises a first compartment 70, 170, 270 arranged under said flow opening 66. The first compartment 70, 170, 270 is thus capable of receiving by gravity the first lubricating product injected by the first pump 62 into the upper casing 32.

[0034] Preferably, as in the embodiments of the figures 1 à 3 , the first compartment 70, 170, 270 is fluidically connected to the first pump 62. Thus, a closed circuit of first lubricant product is formed by said first pump 62, the first injection pipe 64, the upper casing 32, the flow opening 66 and the first compartment 70, 170, 270.

[0035] Preferably, as in the embodiments of the figures 1 à 3 , the first injection pipe 64 is arranged inside the internal space 40 of the support 34, 134, 234. One end 72 of said first injection pipe 64 passes through the partition 35 of the main casing 12, 112, 212, so as to fluidically connect the first pump 62 to the upper casing 32.

[0036] In the drive device 10 shown in the figure 1 , the first pump 62 of the first lubrication unit 24 is fixed on the base 36, outside the internal space 40 of the support 34. Said first pump 62 is fluidically connected to the first injection pipe 64 by a first inlet socket 74 passing through the cylindrical wall 38.

[0037] In a variant not shown, the first pump 62 is fixed to the cylindrical wall 38.

[0038] Furthermore, in the drive device 10, the support 34 is devoid of internal walls and the first compartment 70 is formed by the bottom of the internal space 40. Said first compartment 70 is fluidically connected to the first pump 62 by a first outlet socket 76 passing through the cylindrical wall 38.

[0039] Furthermore, in the drive device 10, the flow opening 66 is radially further from the first vertical axis 30 than the radial bearing 46.

[0040] In the drive devices 110 and 210, respectively shown in figures 2 And 3 , the first pump 62 of the first lubrication unit 124, 224 is received in the internal space 40 of the support 134, 234.

[0041] In the drive device 110 of the figure 2 , the flow opening 66 is centered on the first axis 30. The first compartment 170 is formed by a conduit delimited by a wall. Said conduit is arranged vertically in the internal space 40, between said flow opening 66 and the first pump 62.

[0042] In the drive device 210 of the figure 3 , the support 234 comprises an internal wall 280 of substantially cylindrical shape, extending into the internal space 40 from the base 36. Said internal wall 280 divides the internal space into the first 270 and a second 282 compartments, coaxial along the first axis 30.

[0043] The first compartment 270 is located at the periphery, between the internal wall 280 and the cylindrical wall 38. The flow opening 66 is located directly above said first compartment 270.

[0044] The second compartment 282 is surrounded by said first compartment 270 and receives the first pump 62. The first compartment 270 is fluidically connected to said first pump by a communication socket 284 passing through the internal wall 280.

[0045] The above description of the first lubrication unit 24, 124, 224 corresponds to a low pressure supply of first lubricating product, between the axial bearing 16 and the rotating plate 14. Such a supply is adapted to an axial bearing 16 with hydrodynamic pads.

[0046] In a variant not shown, with a bearing 16 with hydrostatic pads, the first lubrication unit further comprises a second high pressure supply, between the axial bearing 16 and the rotary plate 14.

[0047] The at least one second lubrication unit 26, 126, 226 of the drive device 10, 110, 210 is capable of injecting a second lubricating product, such as an oil, into the at least one drive pinion 20. The first and second lubricating products may be identical or different.

[0048] Preferably, in the drive device 10, 110, 210, the or each drive unit 22 is associated with a second lubrication unit 26, 126, 226.

[0049] The second lubrication unit 26, 126, 226 comprises a second pump 85, a second injection pipe 86 and a recovery pipe 87. The second injection pipe 86 and the recovery pipe 87 fluidly connect the second pump 85 to the at least one pinion housing 51, so as to inject second lubricating product onto the at least one drive pinion 20 and to recover said second product by flow.

[0050] Preferably, the second pump 85 is arranged below the at least one pinion housing 51, so as to promote gravity flow in the recovery pipe 87.

[0051] In the 10 and 110 drive devices of the figures 1 And 2 , the second injection pipe 86 and the recovery pipe 87 of the second lubrication unit 26, 126 pass through the internal space 40 of the support 34, 134 and the upper casing 32 to end at the pinion casing 51.

[0052] In the drive devices 10 and 210, respectively of the figure 1 and of the figure 3 , the second pump 85 of the second lubrication unit 26, 226 is fixed on the base 36, outside the internal space 40 of the support 34, 234 and close to the reducer 54.

[0053] In a variant not shown, the second pump 85 is fixed to the wall 38.

[0054] In the drive device 10 of the figure 1 , said second pump 85 is fluidically connected to the second injection pipe 86 and to the recovery pipe 87, respectively by a second inlet socket 88 and by a second outlet socket 89 passing through the cylindrical wall 38.

[0055] In the drive device 210 of the figure 3 , the second injection pipe 86 and the recovery pipe 87 are arranged outside the internal space 40 and protected by a secondary casing 290, fixed to the outside of the cylindrical wall 38 of the support 234.

[0056] Furthermore, in the embodiments shown, the at least one second lubrication unit 26, 126, 226 of the drive device 10, 110, 210 is capable of injecting the second lubricating product into the reducer 54 of the associated drive unit 22. For this purpose, the second pump 85 is fluidically connected to the reducer casing 56, by an inlet duct 91 and an outlet duct 92 arranged outside the internal space 40.

[0057] Optionally, the inlet 91 and outlet 92 conduits are covered with a protective sheath 293, as in the embodiment of the figure 3 .

[0058] In the drive device 110 of the figure 2 , the second pump 85 of the second lubrication unit 126 is received in the internal space 40 of the support 134. Said second pump 85 is fluidically connected to the inlet 91 and outlet 92 conduits, respectively by a third inlet socket 194 and by a third outlet socket 195 passing through the cylindrical wall 38. The third outlet socket 195 opens onto a T-junction 196, located in the internal space 40 and connected to the recovery pipe 87 and to the second pump 85.

[0059] A method of operating the device 10, 110, 210 will now be described. The motor(s) 52 are put into operation, which rotates the output shaft 60 of the or each drive unit 22. The shaft 60 rotates the or each drive pinion 20. Said drive pinion 20 or each drive pinion 20 meshes with the toothed ring 18, driving said ring 18, and the rotary plate 14, in rotation about the first axis 30.

[0060] In parallel, the first pump 62 of the first lubrication unit 24, 124, 224 is put into operation. Via the first injection pipe 64, a flow of first lubricating product is sent into the upper casing 32 between the axial bearing 16 and the rotary plate 14. Said flow then flows by gravity through the flow opening 66, into the first compartment 70, 170, 270 of the internal space 40 of the support 34, 134, 234. The first lubricating product thus recovered is then returned by the first pump 62 to the upper casing 32.

[0061] In parallel, the second pump 85 of the second lubrication unit 26, 126, 226 is put into operation. Via the second injection pipe 86, a first flow of second lubricant product is sent into the pinion housing 51 to lubricate the drive pinion 20. Said first flow then flows by gravity through the recovery pipe 87 to reach the second pump 85.

[0062] Furthermore, a second flow of second lubricating product is sent into the gearbox casing 56 by the second pump 85, via the inlet duct 91. The mechanical components of the gearbox 54 are thus lubricated. The second flow of second lubricating product then flows towards the second pump 85, via the outlet duct 92.

[0063] In the drive device 110 of the figure 2, the first and second streams of second lubricant product join at the T-junction 196, before returning to the second pump 85.

[0064] The drive devices 10, 110 and 210 described above allow recovery of the first lubricant product inside the main casing 12, 112, 212, which eliminates the need to provide a specific pit for this purpose in the room receiving the crusher 11, 111, 211. In addition, the location of the first injection pipe 64 inside the main casing makes it possible to protect said pipe from dust and mechanical shocks.

[0065] Likewise, the first pump 62 is advantageously protected from shocks and vibrations by its arrangement on the base 36 or in the internal space 40 of the main casing.

[0066] Similarly, the pipes 86, 87 of the second lubrication unit 26, 126, 226 are advantageously protected in the main casing 12, 112 or in a secondary casing 290; and the second pump 85 and the reducer 54 are protected from shocks and vibrations by their arrangement on the base 36 or in the internal space 40 of the main casing.

Claims

1. A drive device (10, 110, 210) for a vertical roller mill, said device comprising: - a main casing (12, 112, 212) defining an internal space (40); - a rotary plate (14) movable in rotation with respect to the main casing, about a first vertical axis (30); said rotary plate being attached or able to be attached to a rotary grinding table of the vertical roller mill; - an axial bearing (16) secured to the main casing, the rotary plate (14) being disposed in vertical support on said axial bearing; - an output ring gear (18), secured to the rotary plate; - at least one drive pinion (20) meshing or capable of meshing with the output ring gear (18), the at least one drive pinion (20) being rotatable about a second axis (50); - at least one drive unit (22), able to rotate the at least one drive pinion; and - a first lubrication unit (24), capable of injecting a first lubricating product under pressure between the rotary plate and the axial bearing; the drive device being characterized in that the internal space (40) of the main casing comprises a first compartment (70, 170, 270) disposed under the axial bearing, said first compartment being configured (66) to receive, by gravity, the first lubricant product injected by the first lubrication unit between the rotary plate and the axial bearing.

2. The drive device according to claim 1, wherein the first lubrication unit comprises: a first pump (62); and a first injection pipe (64) for injecting the first lubricant product, the first injection pipe connecting the first pump to the axial bearing, the first injection pipe being received in the internal space (40) of the main casing.

3. The drive device (110, 210) according to claim 2, wherein the first pump (62) is received in the internal space (40) of the main casing.

4. The drive device (10) according to claim 2, wherein the first pump (62) is disposed outside the internal space.

5. The drive device according to one of the preceding claims, further comprising: a pinion housing (51) enclosing the at least one drive pinion (20); and at least a second lubrication unit (26, 126, 226) capable of injecting a second lubricant product into the pinion housing.

6. The drive device according to claim 5, wherein the at least one second lubrication unit (26, 126, 226) comprises a second pump (85) and at least one second injection (86) or recovery (87) pipe for the second lubricant product, the second injection pipe and / or the recovery pipe connecting the second pump to the pinion housing (51).

7. The drive device (10, 110) according to claim 6, wherein the at least one second injection (86) or recovery (87) pipe is received in the internal space (40) of the main casing.

8. The drive device (210) according to claim 6, wherein the at least one second injection (86) or recovery (87) pipe is disposed outside the internal space, the drive device comprising a secondary casing (290) alongside the main casing and receiving said second injection or recovery pipe.

9. The drive device according to one of claims 5 to 8, wherein the at least one second lubrication unit (26, 126, 226) is capable (91, 92) of injecting the second lubricant product into the at least one drive unit (22).

10. A vertical roller mill (11, 111, 211), comprising a grinding table and rollers suitable for rolling on the table, said mill comprising a drive device (10, 110, 210) according to one of the preceding claims, the rotary plate (14) of said drive device being attached to the grinding table.

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