Milling attachment for a soil milling machine, milling drum for such a milling attachment, and soil milling machine with such a milling attachment

Abstract

Milling device (2) for a soil milling machine (1), in particular a road milling machine, a recycler, a stabilizer or a surface miner, comprising a) a milling drum (8) mounted in a milling drum housing (21), interchangeable and rotatable about a rotation axis (13) extending horizontally and transversely to the working direction (a) of the milling device (2), with a milling tube (9) and with machining tools (11) arranged on the outer surface (10) of the milling tube (9), wherein the milling drum housing (21) comprises at least two side walls (21a, 21b) between which the milling drum (8) is arranged, b) a milling drum drive device (14), c) a drive gearbox (7) which transmits a drive force from the milling drum drive device (14) to the milling drum (8), d) a floating bearing (22) opposite the drive gear (7) in the axial direction of the rotation axis (13) of the milling drum (8), wherein a positive locking coupling (17) arranged inside the milling drum with a clamping device (23) arranged on the floating bearing side (B) for axial securing of the milling drum (8) is provided for torque transmission to the milling tube (8), characterized in that the positive locking coupling (17) is designed for transmitting radial forces, and that the positive locking coupling (17) has a face toothing.

Description

[0001] The invention relates to a milling device for a soil milling machine, in particular a road milling machine, a recycler, a stabilizer or a surface miner, and a milling drum for use with such a milling device and a soil milling machine, in particular a road milling machine, a recycler, a stabilizer or a surface miner, with such a milling device.

[0002] A milling attachment of this type for a soil milling machine comprises an interchangeable milling drum rotatable about a rotational axis, in particular one that is horizontal and transverse to the direction of travel or work, with a milling tube and with machining tools arranged on the outer surface of the milling tube. The milling drum is usually arranged in a so-called milling drum housing, which is open towards the ground and is attached to the soil milling machine. The milling drum housing comprises at least two side walls between which the milling drum is mounted. Furthermore, a milling drum drive unit and a drive gearbox are provided, the latter transmitting a drive force from the milling drum drive unit to the milling tube. For this purpose, the drive gearbox includes, for example, a drive gearbox housing arranged inside the milling drum, through which the drive force is transmitted from the drive gearbox to the milling drum.A typical drive mechanism consists of a belt drive with a reduction gear on the output side. The drive energy required to rotate the milling drum around its axis of rotation is supplied by the milling drum drive unit, for example, an internal combustion engine. The milling drum is usually supported within the milling drum housing by at least two bearing points opposite each other in the direction of the axis of rotation, specifically, for example, a bearing on the drive gear side and a floating bearing axially opposite this bearing. The side wall of the milling drum housing on the floating bearing side is, for example, designed to be removable, so that the milling drum can be pulled laterally out of the milling drum housing via the floating bearing side.

[0003] Such milling equipment is used particularly in road milling machines, recyclers, stabilizers, or surface miners. Typical applications for milling equipment of this type include road and path construction as well as the surface extraction of soil materials, for example, for raw material extraction. These construction machines have in common that they feature a hollow cylindrical milling drum, usually arranged transversely to the direction of travel, which is guided horizontally over the ground to be processed during operation and mills the subsoil to the desired depth.

[0004] In practical applications of such a milling unit for a soil milling machine, it has proven advantageous to design the milling unit in such a way that the milling drum is interchangeable. This allows, among other things, a particularly efficient counteracting of downtime caused by wear and / or damage to the milling drum. At the same time, the range of applications for such machines can be significantly expanded and optimized, as a variety of different milling drum types can now be used. Prior art includes rotor exchange systems in which a bearing of the milling drum is designed to be removable for changing the milling drum, and the milling drum can then be pulled out of the milling drum housing with the bearing detached. Such rotor exchange systems are disclosed, for example, in DE 102 32 489 A1, DE 40 37 448 A1, DE 10 2006 015 506 B3, and DE 200 23 999 U1.

[0005] The object of the invention is to provide a milling device that enables faster and easier replacement of the milling drum compared to known systems. At the same time, the milling device should enable reliable milling operation.

[0006] The problem is solved using a milling device, a milling drum, and a soil milling machine according to the independent claims. Preferred embodiments are specified in the dependent claims.

[0007] A key aspect of the invention lies in providing a positive-locking coupling located inside the milling tube for torque transmission from the drive drive, in particular from the part of the drive housing located inside the milling drum or a housing cover of the drive drive, to the milling tube of the milling drum. This coupling is designed to simultaneously transmit drive torque and radial forces. Radial forces are forces acting radially to the axis of rotation of the milling tube and serve, in particular, to center the milling drum relative to the axis of rotation during milling. By transmitting the radial forces via the coupling components of the positive-locking coupling, the mounting and support of the milling tube in the radial direction with respect to the axis of rotation of the milling drum is thus ensured.Simultaneously, the drive torque is transmitted in the direction of rotation via the positive-lock coupling, so that the present positive-lock coupling, in its inventive design, fulfills a dual function. The positive-lock coupling thus serves as both a power transmission element and a bearing point for the milling drum inside the milling drum housing. To achieve stable and reliable bearing and power transmission via the positive-lock coupling, the positive-lock coupling includes a clamping device arranged on the floating bearing side, which ensures the axial securing of the milling tube when the positive-lock coupling is engaged. The clamping device is thus designed in such a way that the axial position of the milling tube along the axis of rotation is fixed and, in particular, maintained during operation.The clamping effect achieved with the clamping device also serves to establish and maintain the coupling engagement in a manner described in more detail below. The positive locking elements of the positive locking coupling are preferably arranged spatially separated from the clamping device. The clamping device ensures the engagement of the positive locking elements of the positive locking coupling, particularly during milling operations. This is achieved by designing the clamping device in such a way that it prevents axial displacement of the milling tube along the axis of rotation in the installed state, at least from a certain displacement position, or, in particular, exerts a clamping force in the direction of the positive locking of the positive locking elements of the positive locking coupling. Radial forces are defined as those forces that act radially to the axis of rotation.The design of the positive-lock coupling for transmitting radial forces ensures that the milling drum is centered on the axis of rotation, particularly within the coupling itself. Additional centering and fastening elements are therefore unnecessary. The positive-lock coupling thus serves to transmit both torque and radial forces. Furthermore, the installation of the milling tube is significantly simplified, as the positive locking of the coupling's elements facilitates both the axial torque transmission (i.e., to the milling drum's rotational drive) and the positioning of the milling tube concentrically to the axis of rotation.As soon as the positive locking elements of the positive locking coupling engage, torque transmission to the milling tube and simultaneous concentric alignment of the milling tube with the axis of rotation are ensured. The arrangement of the clamping device on the loose bearing side has proven particularly effective here. This arrangement allows access to the clamping device from the side of the milling drum housing opposite the drive gearbox, which is especially advantageous for assembly and disassembly.

[0008] The drive unit is arranged at the end face of the milling tube and projects at least partially, particularly with at least parts of a reduction gear, into the interior of the milling tube. Preferably, the drive housing includes a cover element through which the output-side drive force of the drive unit is transmitted to the milling tube of the milling drum via the positive-locking coupling. The cover element is thus part of the drive train. It has proven particularly advantageous if the positive-locking coupling supports the milling tube at a radial distance from the drive housing and, in particular, from the cover element. In this embodiment, the milling tube does not rest directly on the outer surface of the drive housing with its inner surface, but is held radially in the direction solely by the positive-locking coupling and is arranged with its inner surface radially spaced from the outer surface of the cover element relative to the axis of rotation.Between the milling tube or the coupling element connected to the milling tube and the drive housing, there is a radially circumferential clearance or annular gap. This is advantageous because the positive-lock coupling alone is responsible for maintaining a defined position, and no other components need to be adapted accordingly. Furthermore, the assembly of the milling drum is simplified, since the engagement of the coupling elements of the positive-lock coupling simultaneously ensures both the transmission of drive force and the desired positioning of the milling drum within the milling drum housing.

[0009] For the design of the positive-lock coupling, it is important that it is capable of transmitting radial forces. Ideally, therefore, all positive-lock coupling designs are those that allow the coupling elements to engage simply by inserting the milling drum into the interior of the milling drum housing. According to the invention, a positive-lock coupling design with face teeth is provided. In this embodiment, the positive-locking elements of the positive-lock coupling engage radially via face teeth extending in the axial direction of the axis of rotation to transmit torque and secure the position of the milling tube. A face tooth in this sense is thus characterized by having interlocking tooth elements extending in the axial direction of the milling tube, for example, in the form of a Hirth tooth.The teeth of the face gear are thus arranged on the face of a gear element, which will be described in more detail below, and project axially, i.e., in the direction of the cylinder axis of the milling tube. The gear elements therefore extend in the direction of the rotation axis of the milling drum, or the tooth tips of the individual teeth are at least partially offset from the tooth valleys in the axial direction of the rotation axis. The teeth of the face gear thus extend axially in height. A significant advantage of such a face gear is, in particular, its self-centering property with respect to the rotation axis and its easy assembly / disassembly for engagement, which is achieved by sliding the coupling halves on / off in the axial direction of the rotation axis.The face gearing also creates a multi-wedge effect in the axial direction of the rotation axis, so that a large portion of the circumferential force is transmitted positively via the wedge surfaces of the face gearing. Additionally, the positive-locking coupling can be designed as a jaw coupling.

[0010] It is preferred that the flanks of the teeth of the face gear are wedge-shaped and, in particular, symmetrical. This has the advantage that the torque transmission through the teeth of the face gear is uniform in both co-rotating and counter-rotating operation of the milling drum. This does not require that the flanks of the teeth be designed as flat surfaces, although this design has proven to be preferred.

[0011] The teeth of the face gear are ideally formed in relation to the axis of rotation such that the upper edges (edges pointing axially away from the respective coupling half or running along a tooth crest) and lower edges (edges running in a tooth valley) of the teeth, when extended, intersect the axis of rotation of the milling drum. In other words, the upper and lower edges of the teeth are aligned so that they lie on straight lines extending radially from the axis of rotation in the plane of rotation (plane perpendicular to the axis of rotation), causing the teeth to taper from the outside towards the axis of rotation. This type of tooth flank design, in particular, ensures a very simple radial fit of the milling tube through the positive-lock coupling.In addition to straight-tooth arrangements, helical (the upper and lower edges of the teeth run obliquely to the radial axis of rotation or are tilted relative to the radial axis in a plane perpendicular to the axis of rotation) and / or curved, especially spiral, spur gear designs can also be used. The spur gear can thus be constructed from straight teeth; however, spur gears made of helical teeth and especially circular teeth are preferred. With the help of these gear alternatives, which are modified compared to straight-tooth spur gears, optimized torque transmissions, optimized centering functions, etc., can be achieved, depending on the application.

[0012] The positive-lock coupling preferably comprises at least two coupling halves, one of which is rigidly connected to the inside of the milling tube and projects radially into the interior of the milling tube, while the other coupling half is connected to the drive transmission. This arrangement ensures that the positive-lock coupling, or at least the two coupling halves required for the positive engagement, are located inside the milling tube and are therefore arranged in a particularly space-saving manner. The two coupling halves are preferably each designed as circumferential ring elements with complementary toothing.

[0013] The connection of the other coupling half to the drive unit is ideally made via the outside of the gearbox housing or a part of the drive unit designed for power transmission. This coupling half is, for example, firmly connected to the outer shell of the gearbox housing, in particular to a hollow cylindrical, rotatable housing cover of the gearbox housing. In the installed state of the milling tube, the drive unit, at least partially, protrudes into the interior of the milling tube with the gearbox housing, especially with the housing cover. The housing cover is thus part of the drive unit, but it is rotatable and simultaneously serves as a power transmission element for the drive unit.

[0014] In principle, the milling device according to the invention is designed such that, after the clamping device on the floating bearing side is released, the milling drum can be pulled away from the positive-locking coupling, or one half of the positive-locking coupling, in the axial direction of the axis of rotation and removed from the milling drum housing. To facilitate this process, the positive-locking coupling in particular has a pressurization device for pressurizing the positive-locking coupling with fluid to separate the coupling halves. A preferred fluid is, for example, air. The pressurization device can also include means, for example, a cylinder-piston unit, by which the milling drum can be pushed away from the positive-locking coupling engagement towards the floating bearing.

[0015] To ensure reliable power transmission through the positive-lock coupling and to reduce wear, it is advantageous to protect the coupling area from external contamination. This is achieved particularly well with a protective sleeve that shields the coupling halves from external elements when engaged. The protective sleeve provides an externally shielded gearing chamber within which the gears of the two coupling halves mesh to form a positive connection. The protective sleeve is, for example, positioned on the coupling half on the drive transmission side and extends axially towards the floating bearing over the area of ​​the coupling halves.To ensure a tight fit of the protective sleeve, it may also have a sealing projection extending radially from the sleeve to the axis of rotation for engagement with a radial groove circumferential on the opposing element, for example the coupling half firmly connected to the inside of the milling tube.

[0016] A further advantage of the milling device according to the invention lies in the fact that a large number of different milling drums can be used, for example, with regard to working width, distribution, and type of machining tools, etc. In principle, it is possible to equip each interchangeable milling drum with its own coupling half. However, to reduce acquisition and operating costs, it has proven advantageous if at least the coupling half connected to the milling tube is detachably attached to the milling tube. Naturally, the other coupling half, on the gearbox side, can also be detachably attached, particularly to the drive housing. This has the advantage that the coupling half of the milling tube is attached to the respective milling drum to be operated, and thus only one coupling half is required for different milling drums.On the other hand, the elements of the positive locking coupling can be selectively replaced, for example in the case of increased wear, so that a complete replacement of the milling tube and / or the connection on the gearbox-side coupling part of the positive locking coupling is not necessary.

[0017] Specifically, the coupling halves are connected to the gearbox housing and the milling tube, respectively, via screw connections. These screw connections run parallel to the axis of rotation. They are designed in such a way that they do not extend into the positive-locking area of ​​the positive-lock coupling, such as the face teeth. To this end, the coupling halves feature, for example, corresponding blind holes with internal threads, through which screw connections with fastening screws engage from the opposite side of the coupling halves, for example, via a suitable bearing ring.

[0018] A key element of the invention lies in the positive locking mechanism of the positive-lock coupling for transmitting radial forces. As mentioned above, the positive-lock coupling is preferably designed such that the positive-locking elements of the coupling can be slid against one another in the axial direction to maintain the positive lock, and that rotor centering relative to the axis of rotation is simultaneously achieved via the positive-lock coupling. For mounting the milling drum in the milling drum housing of the milling unit, it has proven particularly helpful to have a centering aid arranged between the gearbox housing and the floating bearing along the axis of rotation, and which increases in size radially from the floating bearing towards the gearbox housing in the direction of the axis of rotation.Specifically, the centering aid is designed to facilitate and support the engagement of the positive locking elements when the milling drum is inserted into the milling drum housing. For this purpose, a centering aid that is at least partially conical, positioned between the gearbox housing and the floating bearing, has proven particularly effective. The conical axis of the conical section runs coaxially with the axis of rotation of the milling drum. The conical section tapers towards the floating bearing side, so that the milling drum is lifted towards the drive-gear-side part of the positive locking coupling when inserted into the milling drum housing. This significantly simplifies assembly. The conical section is preferably rigidly connected to the drive housing and, in particular, its housing cover.

[0019] The clamping device can also vary in many ways. Its main function is to clamp the milling drum in the milling drum housing at the floating bearing in such a way that the positive engagement of the positive-lock coupling is ensured during operation. In other words, the clamping device is designed, at a minimum, to prevent axial displacement of the milling drum towards the floating bearing during operation. Additionally, the clamping device can be designed to exert a clamping force on the milling drum in the direction of the positive locking of the positive-lock coupling (in the axial direction of the rotational axis from the floating bearing to the drive-gear-side part of the positive-lock coupling), in order to ensure, in particular, the centering function of the positive locking of the positive-lock coupling.The clamping device thus ensures a reliable positive locking of the coupling elements, so that, for example, direct screwing of the interlocking positive locking elements is not necessary.

[0020] This can be achieved, for example, with a clamping device that includes a bearing disc or clamping sleeve with a central hole, which is firmly connected to the milling tube at the floating bearing. A connecting element is guided from the gearbox housing outwards through the central hole inside the milling drum. This connecting element allows a clamping element to be applied to the floating bearing side from outside the interior of the milling drum, thereby limiting the adjustment and, depending on the embodiment, creating a clamping force towards the drive gearbox-side part of the positive-locking coupling.Specifically, the clamping device can, for example, have a shaft journal or tie rod projecting from the drive housing or connecting element along the axis of rotation on the loose bearing side and passing through the central hole, wherein a clamping element, in particular a clamping nut, which can be attached to the shaft journal or tie rod from the outside, is provided for axially securing the milling tube. The shaft journal or tie rod is connected directly or indirectly to the drive housing and, in particular, to the housing cover of the drive housing.

[0021] To achieve a clamping force from the loose bearing towards the drive-gear-side part of the positive-locking coupling, the tie rod is preferably spring-loaded in the axial direction towards the drive housing, which can be achieved in particular by a suitably designed spring assembly. Alternatively, the tie rod can, for example, include a hydraulic clamping device acting in the axial direction.

[0022] The invention further relates to a milling drum for use in a milling device according to one of the embodiments described above. According to the invention, the milling drum has an internal coupling half, or a coupling half projecting inwards from its inner surface, which has a face-mounted engagement toothing for engaging with a driven coupling half connected to the drive housing, in particular to the housing cover of the drive housing, for the transmission of rotational force. The essential element of the milling drum according to the invention is therefore, in particular, the coupling half with face teeth arranged inside the milling tube, with reference being made to the preceding descriptions regarding the specific design of the face teeth.

[0023] Finally, the invention also relates to a soil milling machine, in particular a road milling machine, a recycler, a stabilizer or a surface miner, with a milling device according to the preceding descriptions.

[0024] The invention is explained in more detail below with reference to the embodiment shown in the figures. The figures schematically show: Fig. 1. A side view of a soil milling machine; Fig. 2 a partial cross-sectional view through the milling device in a vertical plane passing through the axis of rotation at the height of the axis of rotation; Fig. 3 embodiment from Fig. 2 with partially removed milling roller; Fig. 4 Enlargement of section II from Fig. 2; Fig. 5. Design: Milling edge on the right with reduced milling width; Fig. 6. Design: Milling edge on the left with reduced milling width; and Fig. 7 Perspective oblique view of the partial cross-section from Fig. 1.

[0025] Identical components are indicated with the same reference numerals in the figures, whereby components that are repeated in the figures are not necessarily labelled again in each individual figure for the sake of clarity.

[0026] Fig. Figure 1 shows a side view of a soil milling machine 1 (specifically, a road milling machine of the front loader type with a central rotor). The working direction (forward direction) is indicated by the arrow a. Essential elements of the soil milling machine are a milling unit 2, a machine frame 3 with a operator's platform 4, and crawler tracks 5 mounted on the machine frame 3 and adjustable in height via lifting columns (although wheeled tracks can also be used as an alternative). The soil milling machine 1 also includes a milling drum drive unit 14, in this case an unspecified internal combustion engine, which provides the energy required for operation. The power transmission from the internal combustion engine to the milling drum 8 is effected via a drive gearbox 7 from the in Fig. 1 Only a side cover for a belt drive part of the drive gearbox 7 is visible. During operation, the soil milling machine 1 is moved over the subsoil 6 in the working direction a and mills with a Fig. 1. The milling drum 8 (not shown) inside the rotor housing 21 collects soil material. Further details regarding the construction and mounting of the milling drum 8 in the rotor housing 21 will be provided in the following sections. Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 to Fig. 7. The Fig. 2, Fig. 3, Fig. 5 and Fig. 6 are a partial sectional view along line II from Fig. 1 in the area of ​​the milling device 2, Fig. Figure 4 is a close-up of section II from Fig. 2 and Fig. Figure 7 is a perspective oblique view of the milling device 2. Fig. 2 from a slightly rear angle.

[0027] The milling device 2 comprises a milling drum 8 with a milling tube 9 and with machining tools 11 arranged on the outer surface 10 of the milling tube 9. The machining tools are located in the Fig. 2, Fig. 3, Fig. 5 and Fig. Figure 6 shows only the upper and lower chisel tips and, framed by the dashed box, the cutting circle 11' of the machining tools 11; in the other figures, the machining tools are not shown for clarity. In practical application, the machining tools 11 are evenly distributed on the outer surface of the milling tube 9. As a precaution, in Fig. Two tool holders 12 are shown by dashed lines as examples. The milling drum 8 is rotatable about a rotational axis 13 in a milling drum housing 21. The milling drum housing 21 comprises two side walls 21a and 21b, a top wall 21c, a front wall 21d, and a rear wall (not shown in the figures). The side 21a of the milling drum housing 21, through which the drive gear 7 is guided from the outside into the interior of the milling drum housing 21, is designated as coupling side A. The side opposite this side A in the axial direction of the rotational axis 13, on which a floating bearing 22 is arranged, is designated as floating bearing side B in the figures. The side wall 21b of the milling drum housing 21 located on the floating bearing side B is removable (for example, in Fig. 3 illustrated in more detail). The milling drum 8 can thus be replaced via this side and inserted into or removed from the interior of the milling drum housing 21, which is open downwards towards the base 6.

[0028] The axis of rotation 13 of the milling drum 8 runs horizontally and transversely to the working direction a. A milling drum drive unit 14, for example an internal combustion engine or similar, is provided to drive the rotational movement of the milling drum 8. The milling drum drive unit 14 is operatively connected to the milling drum 8 via the drive gearbox 7. In addition to a belt drive stage 15, the drive gearbox 7 comprises a reduction gearbox stage 16 arranged on the output side, which transmits a drive force from the milling drum drive unit 14 to the milling tube 9. The milling tube 9 is operatively connected to the reduction gearbox section 16 of the drive gearbox 7 in the manner described in more detail below. The power transmission from the belt drive 15 to the milling tube 9 via the reduction gearbox 16 is not described in all details, particularly regarding the specific design of the individual reduction stages of the reduction gearbox 16.It is essential that the drive force is supplied to the reduction gear 16 via the belt drive 15 and that the force is transmitted to the milling tube 9 via a positive locking coupling 17, the construction and operation of which will be described in more detail below.

[0029] The reduction gear 16 comprises a housing 18 and projects from the outside to the inside through the outer wall of the machine frame 3 or through the wall 21a of the milling drum housing 21, at least with a housing part 19, coming from the belt drive side A, laterally or end-face into the interior of the milling drum housing 21 and into the interior of the milling tube 9. With respect to the axis of rotation 13, this side is hereinafter also referred to as the drive side of the milling tube 9. The housing part 19 is designed like a cover and is rotatable about the axis of rotation 13 relative to the mounting area of ​​the gear housing 18, which is fixedly arranged on the machine frame 3. This part of the gear housing 18 functions as the output element and transmits the drive force via the positive-locking coupling 17 to the milling tube 9 of the milling drum 8.Along the axis of rotation 13, a connecting element 20 adjoins the housing part 19 on the side B of the milling tube 9 opposite the axis of rotation 13 (floating bearing side B). This connecting element 20 has a detachable bearing arrangement, described in more detail below, at its tip. The connecting element 20 is part of a clamping device 23, the function of which is to axially secure the milling tube 9 and, depending on the embodiment, to clamp it. It is important to note that the bearing side of the milling tube 9 opposite the drive side is designed as a floating bearing 22. The milling tube 9 can thus be disassembled on this side, ultimately enabling the milling tube 9 to be replaced.

[0030] A comparison of Fig. 2 and Fig. Figure 3 illustrates the interaction of the individual components of the milling device 7 during rotor replacement. Fig. 2 concerns the installed state of the milling tube 9 and Fig. 3 a partially removed state, as occurs when changing the milling drum 8. The side wall 21b of the rotor housing 21, located on the side of the floating bearing 22 and situated on the zero side of the soil milling machine 1, where the milling drum 8 is almost flush with the machine frame 3 of the soil milling machine 1, can be detached, for example by pivoting upwards or, as in Fig. 3, through complete disassembly.

[0031] For mounting the milling drum 8 in the milling drum housing 21, the milling tube 9 comprises ring elements 24a (drive side) and 24b (floating side) extending radially to the axis of rotation 13 on its inner side. In the present embodiment, these ring elements 24a and 24b are welded firmly to the inner surface of the milling tube 9. The drive-side ring element 24a is connected to one coupling half 17b of the positive-locking coupling 17. The other coupling half 17a of the positive-locking coupling 17, on the other hand, is attached to a retaining ring 25, which is an integral part of the housing cover 19 of the reduction gear 16. Both coupling halves 17a and 17b are designed as ring elements with end teeth oriented in the axial direction 13 (in particular made of...). Fig. 7, in which the coupling half 17a is fully visible and the coupling half 17b is partially visible in a sectional view in a vertical section plane along the axis of rotation 13), wherein the toothing of the two coupling halves engages for positive locking in the coupled state (according to the Fig. 2 and 4 to 7) are complementary to each other. The teeth are also provided circumferentially around the ring, and the teeth of the two coupling halves project with their tooth tips facing each other in the direction of the axis of rotation 13. In the present embodiment, the tooth tips 26a and tooth valleys 26b also extend straight in the radial direction to the axis of rotation 13 and perpendicular to the axis of rotation 13, so that the tooth flanks 26c run in a plane inclined to the plane of rotation (plane perpendicular to the axis of rotation 13). Alternatively, other gear types can be used here, for example, helical gears or cam gears, in particular spiral gears. Further variations include the teeth of the face gear running with their tooth valleys and / or tooth tips in a plane perpendicular to the axis of rotation or, for example, descending or ascending in the axial direction of the axis of rotation.In this way, for example, at least partially conical spur gear structures can be obtained. It is important that the spur gear is designed in such a way that radial forces as well as a rotational torque can be transmitted simultaneously, and that the two coupling halves of the spur gear can be slid against each other along the axis of rotation, either linearly or, if necessary, with partial relative rotation of the two coupling halves about the axis of rotation. The coupling halves are thus essentially complementary to each other in the axial direction in the area of ​​the spur gear.

[0032] A key element for transmitting torque from the drive gearbox 7, and in particular from the reduction gearbox 16, to the milling drum 8 is the positive-locking coupling 17 with the clamping device 23 arranged on the floating bearing side and the two coupling halves 17a and 17b. With respect to the axial direction of the rotation axis 13, the two coupling halves 17a and 17b are arranged inside the milling tube 9 when the positive-locking coupling 17 is engaged and are thus protected from the outside.The specific transmission of the drive force from the milling drum drive unit 14 to the milling drum 8 is carried out as follows: Output of the combustion engine (milling drum drive unit 14) - belt drive 15 - reduction gear 16 with housing part (or cover) 19 rotating around the axis of rotation 13 with a retaining ring 25 attached thereto - coupling half 17a connected to the retaining ring 25 - transmission to the coupling half 17b when the positive locking between the two coupling halves exists in the axial direction of the axis of rotation (ensured by the clamping device 23) - further transmission to the ring element 24a connected to the second coupling half 17b and further transmission to the milling tube 9 of the milling drum 8, which is firmly connected to the ring element 24a. It is therefore essential that the drive force transmission to the milling drum 8 occurs solely via the positively locking coupling halves 17a. and 17b of the positive locking coupling 17 is performed.

[0033] In addition to the pure axial torque transmission, another essential function of the positive-locking coupling 17 is to absorb radial forces and thus ensure the radial alignment of the milling drum 8 or the milling tube 9 with respect to the axis of rotation 13. In other words, the positive-locking coupling 17 is not only designed to transmit torque, but also serves as a support element for the milling drum 8, centering it radially with respect to the axis of rotation 13. This eliminates the need for an additional bearing point to absorb radial forces alongside the positive-locking coupling 17. This is particularly evident in the fact that, when the positive-locking coupling 17 is engaged, the milling tube 9 does not rest on the outer surface 19' of the housing part 19, but is radially spaced from it by an annular gap 27.This is particularly evident from the enlarged section of the image. Fig. 4, which the dashed-bordered area II from Fig. 2 magnified. Fig. Figure 4 illustrates that the special design of the positive-lock coupling 17 ensures that the radial position and centering of the milling tube 9 in the rotor housing 21 is achieved and maintained solely through the engagement of the coupling halves 17a and 17b. The radial forces required for centering the milling tube 9, particularly on the drive side A, are thus transmitted exclusively by the positive-lock coupling 17. This allows the milling tube 9 to be mounted with a radial distance to the outer surface of the corresponding gear element (in this case, the housing part 19), while its inner surface remains free of contact with it. In addition to serving as a torque transmission element, the positive-lock coupling 17 also acts as a bearing (in addition to the floating bearing 22) for the milling drum 8 in the milling drum housing 21.

[0034] To ensure clutch engagement when the milling drum 8 is installed, it is important that the milling tube 9 is secured in its axial position. This is the essential function of the clamping device.

[0035] The clamping device is, in particular with reference to Fig. 3, constructed as follows: On the loose bearing side B, an annular insert 30 is provided, which is firmly screwed to the ring element 24b. This annular insert 30 has a central passage 31 in its center, through which a bearing sleeve 32 of a tie rod 33 is passed. The bearing sleeve 32 forms a bearing against an annular flange 34 of the rotor housing 21, which is mounted in the side wall 21b, by means of a rolling bearing 35 ( Fig. 2) is supported by the floating bearing 22. The tie rod 33 is connected to the rotatable housing part 19 of the drive gearbox 16, which is used for torque transmission, via the connecting element 20. The tie rod, with its tip area facing away from the drive gearbox, is guided through the bearing sleeve 32 in the axial direction of the axis of rotation 13 and secured against axial displacement on the floating bearing side of the bearing sleeve by a fastening and clamping nut 36 and tightened or clamped axially against the connecting element 20. Due to the tension of the tie rod 33, the milling tube 9 is inserted with its coupling half 17b into the coupling half 17a on the housing cover 19 and clamped or secured axially against it. For this purpose, the tie rod 33 is connected, for example, via a thread to the connecting element 20 or another part of the drive gearbox 16.This allows for the selective replacement of the tie rod 33 in the event of damage. The tie rod 33 can also be equipped, for example, with a spring assembly to cushion axial impacts of the milling drum 8 against the side wall 21b and / or to exert a clamping force on the coupling halves 17a and 17b of the positive-locking coupling 17. In conjunction with a suitable design of the face teeth, this can also provide a form of overload protection. It goes without saying that additional means can be provided to mechanically secure the fastening screw 36 against loosening.

[0036] The connecting element 20 is further designed as a body that tapers at least partially. Specifically, the connecting element 20 has a significantly larger diameter on the drive side (adapted to the diameter of the housing part 19) than on the floating bearing side B. This provides the connecting element 20 with a kind of centering aid, which in particular facilitates the insertion of the milling tube 9 into the rotor housing 21 to ensure the positive locking of the positive locking coupling 17. The interior enclosed by the connecting element 20 together with the housing part 19 can, for example, be filled with a coolant, in particular oil, to cool the reduction gear.

[0037] For the proper functioning of the positive-lock coupling 17, it is necessary that the coupling halves 17a and 17b can engage optimally in a positive-locking manner, or that the coupling teeth of the face teeth of the two coupling halves 17a and 17b bear against each other as flatly as possible. For this purpose, it is desirable that the engagement area of ​​the coupling halves 17a and 17b be as free of contaminants as possible. In the present embodiment, a protective sleeve 37 is used for this purpose (particularly visible in Fig. 4) present, which shields the coupling halves 17a and 17b from the outside when coupled. The protective sleeve 37 is integrated and fastened with a radial leg 37a in a screw connection between the retaining ring 25 and the coupling half 17a. An axial leg 37b projects from the radial leg 37a in the axial direction, extending towards the coupling half 17a and overlapping it, at least in its tip region, together with the coupling half 17b, which is in a positive fit, in the axial direction of the axis of rotation 13. In order to obtain a particularly tight seal of the toothed chamber 38, which is closed off to the outside by the axial leg 37b, an annular groove 39 is provided in the toothed ring of the coupling half 17b, circumferentially around the outer surface, into which a sealing projection 37c, projecting inwards from the protective sleeve 37 towards the axis of rotation 13, engages in a sealing manner.The protective sleeve 37, together with the coupling half 17b, forms the annular gear chamber 38, in which the gear teeth of the two coupling halves 17a and 17b are arranged circumferentially around the axis of rotation 13. In the engaged state, the protective sleeve 37 thus shields the gear teeth from the outside, preventing dirt from entering the gear teeth area.

[0038] The coupling halves 17a and 17b are each detachably arranged on their respective bearing rings 24a and 25. For this purpose, screw connections are provided in each coupling half 17a or 17b, comprising a through bore 40a or 40b and a blind bore 41a or 41b, through which a fastening screw 42 passes. The screw connections are further arranged such that the fastening screws 42 can be screwed into the coupling halves 17a and 17b facing each other. In other words, the screw connections are designed such that the fastening screws are not screwed in via the positive-locking or toothed area, but rather from the side opposite the toothed area of ​​each coupling half. This prevents fasteners from protruding into the toothed area.By loosening the fastening screws 42, the coupling halves 17a and 17b can be detached from their respective support parts and thus, for example, selectively replaced.

[0039] In practical applications of such milling devices 2, different milling widths b and / or partial milling operations with respect to the maximum milling width are often desired. The present embodiment of the milling device 2 offers the possibility of realizing different milling widths b using different interchangeable rotors 8. Fig. 2, Fig. 3 and Fig. Figure 7 illustrates the use of a milling drum 8, whose milling width b extends almost completely across the width of the rotor housing 21 and thus essentially corresponds to the maximum milling width. Fig. 5 and Fig. In contrast, section 6 concerns milling drums 8, which, together with a length compensation tube (or adapter tube), have a significantly smaller milling width b, which corresponds to only a fraction of the maximum milling width. Viewed in the working direction a, the arrangement in Fig. 5 on the zero side (right) and in Fig. 6 on the side A opposite the zero side. The milling rollers 8 each have an axially shortened milling tube 9, which is connected to a length compensation tube. Of course, variants are also conceivable in which the adapter tube is detachably connected to the milling roller 8. The essential function of the adapter tube in both embodiments is to bridge the axial gap between the end of the milling roller and the positive locking coupling 17 ( Fig. 5) or the loose bearing side B ( Fig. 6). At the in Fig.In the embodiment shown in Figure 5, the positive-locking coupling 17 with face teeth 28 is arranged on the length compensation tube of the milling drum 8. With regard to the assembly and disassembly process, the present shortened milling drums 8 with adapter piece thus have the advantage that, with respect to the individual assembly and disassembly steps, there are no changes compared to the milling drum 8 from the other figures with almost maximum milling width.

Claims

[1] Milling device (2) for a soil milling machine (1), in particular a road milling machine, a recycler, a stabilizer or a surface miner, comprising a) a milling drum (8) mounted in a milling drum housing (21), interchangeable and rotatable about a rotation axis (13) extending horizontally and transversely to the working direction (a) of the milling device (2), with a milling tube (9) and with machining tools (11) arranged on the outer surface (10) of the milling tube (9), wherein the milling drum housing (21) comprises at least two side walls (21a, 21b) between which the milling drum (8) is arranged, b) a milling drum drive device (14), c) a drive gearbox (7) which transmits a drive force from the milling drum drive device (14) to the milling drum (8), d) a floating bearing (22) opposite the drive gear (7) in the axial direction of the rotation axis (13) of the milling drum (8), wherein a positive locking coupling (17) arranged inside the milling drum with a clamping device (23) arranged on the floating bearing side (B) for axial securing of the milling drum (8) is provided for torque transmission to the milling tube (8), characterized by , that the positive locking coupling (17) is designed to transmit radial forces, and that the positive locking coupling (17) has a face toothing. [2] Milling device (2) for a soil milling machine (1) according to claim 1, characterized by , that the positive locking coupling (17) is designed in such a way that the milling tube (9) is supported on the side opposite the floating bearing (22) in the radial direction exclusively by coupling elements, and that an annular gap (27) is present between the inner shell of the milling tube (9) and an element adjacent to the axis of rotation (13) in the radial direction. [3] Milling device (2) for a soil milling machine (1) according to one of the preceding claims, characterized by that the flanks of the teeth of the front teeth are wedge-shaped or trapezoidal and, in particular, symmetrical. [4] Milling device (2) for a soil milling machine (1) according to one of the preceding claims, characterized by , that the upper and lower edges of the teeth of the face gearing in their extension intersect the axis of rotation of the milling drum (8) and / or are curved, in particular as spiral teeth. [5] Milling device (2) for a soil milling machine (1) according to one of the preceding claims, characterized by , that the positive locking coupling (17) is a jaw coupling. [6] Milling device (2) for a soil milling machine (1) according to one of the preceding claims, characterized by, that the positive locking coupling (17) comprises two coupling halves (17a, 17b), wherein one coupling half (17b) is firmly connected to the inside of the milling tube (9) and projects radially into the interior of the milling tube (9) and the other coupling half (17a) is connected to the drive gear (7). [7] Milling device (2) for a soil milling machine (1) according to claim 6, characterized by , that the two coupling halves (17a, 17b) are each designed as a toothed ring with axially directed teeth. [8] Milling device (2) for a soil milling machine (1) according to one of claims 6 or 7, characterized by , that the positive locking coupling (17) has a pressure application device for applying fluid pressure to the positive locking coupling (17) to separate the coupling halves (17a, 17b), in particular in the axial direction. [9] Milling device (2) for a soil milling machine (1) according to one of claims 6 to 8, characterized by, that a protective sleeve (37) is present which shields the coupling halves (17a, 17b) from the outside when coupled. [10] Milling device (2) for a soil milling machine (1) according to one of claims 6 to 9, characterized by , that at least the coupling half (17b) connected to the milling tube (9) is detachably attached to the milling tube (9). [11] Milling device (2) for a soil milling machine (1) according to one of claims 6 to 10, characterized by , that the other coupling half (17a) is arranged on an outer shell of a gearbox housing (18). [12] Milling device (2) for a soil milling machine (1) according to claim 11, characterized by , that the coupling halves (17a, 17b) are each connected to the gearbox housing (18) or to the milling tube (9) via screw connections. [13] Milling device (2) for a soil milling machine (1) according to one of claims 11 or 12, characterized by, that at least a partially conical centering aid (20) is present between the gearbox housing (18) and the floating bearing (22) along the axis of rotation (13), which increases from the floating bearing (22) towards the gearbox housing (18) in the radial direction to the axis of rotation (13). [14] Milling device (2) for a soil milling machine (1) according to one of claims 11 to 13, characterized by , that the clamping device (23) on the loose bearing (22) comprises a bearing disk (30) fixedly connected to the milling tube (9) with a central hole (44), wherein a connecting element (20) is guided outwards from the gearbox housing (18) through the central hole (44). [15] Milling device (2) for a soil milling machine (1) according to one of claims 11 to 14, characterized by, that the clamping device (23) has a shaft journal or tie rod (33) projecting from the gear housing (18) or connecting element (20) on the loose bearing side (B) and passing through the central hole (44), and that a clamping element, in particular a clamping nut (36), which can be attached from the outside to the shaft journal or tie rod (33) is provided for axial securing of the milling tube (9). [16] Milling device (2) for a soil milling machine (1) according to claim 15, characterized by , that the tie rod (33) is spring-loaded in the axial direction towards the gearbox housing (18). [17] Milling device (2) for a soil milling machine (1) according to one of claims 15 or 16, characterized by , that the tie rod (33) comprises a hydraulic tensioning device acting in the axial direction. [18] Milling drum for use in a milling device (2) according to the preceding claims characterized by, that the milling drum (8) has an internal coupling half (17b) with a face-protruding engagement toothing for engagement with a driven coupling half (17a) connected to a gearbox housing (18) for torque and radial force transmission. [19] Soil milling machine (1), in particular road milling machine, recycler, stabilizer or surface miner, with a milling device (2) according to any one of claims 1 to 17.

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