This application claims benefit of German Patent Application No. DE 10 2020 105 391.6, filed on Feb. 28, 2020, and which is hereby incorporated by reference in its entirety.
The present invention relates to an earth working machine, such as for example a road milling machine, a recycler, a stabilizer or a surface miner, comprising a support structure and a working assembly mounted on the support structure so as to be rotatable about a drive axis relative to the support structure, the drive axis defining an axial direction along the drive axis, a radial direction orthogonal thereto and a circumferential direction about the drive axis, in a reference state ready for a rotation of the working assembly about the drive axis, the working assembly being rotatably mounted by a first rotary bearing on a first support structure area at a drive axial end and being rotatably mounted by a rotary bearing arrangement on a second support structure area at a retention axial end situated remotely from the drive axial end in the axial direction, the rotary bearing arrangement including a second rotary bearing, an assembly-side bearing configuration connected to the working assembly and a structure-side bearing configuration connected to the support structure, the retention axial end as the assembly-side bearing configuration having a configuration including one of a bearing stem and a bearing sleeve and the second support structure area as the structure-side bearing configuration having the respectively other configuration including the other of the bearing stem and the bearing sleeve, the bearing sleeve surrounding the bearing stem in the reference state, both the bearing stem as well as the bearing sleeve being situated rotatably about the drive axis relative to the second support structure area in the reference state, and the bearing stem and the bearing sleeve being designed to be axially removable from one another and thereby separable from one another for maintenance, refitting and assembly purposes.
The present invention furthermore relates to a support structure designed for connection to a machine frame of an earth working machine, implemented in particular as a milling drum housing, which has a plurality of connection configurations for the releasably designed connection to a machine frame of an earth working machine. The support structure comprises a working assembly that is mounted on the support structure so as to be rotatable about a drive axis relative to the support structure for the purpose of earth working and is otherwise designed as indicated in the previous paragraph.
An earth working machine of this type in the form of a road milling machine and a support structure of this type in the form of a milling drum housing are known from EP 3406798 A1 (US 10,724,188).
The second support structure area of the known earth working machine, as a maintenance hatch or maintenance door of the milling drum housing, is swivable about a swivel axis that is essentially parallel to the yaw axis of the earth working machine in order to achieve, by swiveling the maintenance door, an accessibility of a milling drum accommodated in the milling drum housing or a drive configuration supporting the latter as components of a known working assembly. When the maintenance door is open, the milling drum may be pulled off axially from the drive configuration that supports it and may be replaced by another milling drum for example.
The bearing stem and the bearing sleeve are designed in such a way that when opening the maintenance door, the structure-side bearing configuration, in the known case a bearing sleeve, is axially pulled off the assembly-side bearing configuration, in the known case a bearing stem, with the swivel movement of the maintenance door. Due to the swivel movement, the movement of pulling the bearing sleeve off the bearing stem is not a pure axial relative movement, but rather the predominantly axial translatory component of the pull-off movement has superimposed on it an, in terms of absolute value, smaller radial translatory and a rotatory movement component of the bearing sleeve.
Because of the advantageously simple and quick separability of the structure-side and the assembly-side bearing configurations of the rotary bearing arrangement, the aforementioned bearing configurations in the reference state are coupled together only in frictionally engaged fashion for the joint rotary movement about the drive axis. In the earth working operation of the earth working machine, it is possible that in certain operating situations, in which there is a brief elevated radial load of the rotary bearing of the working assembly, for example when the working assembly begins to move and/or when the working assembly is applied to the ground to be worked and/or when changing an engagement depth of the working assembly orthogonal to the drive axis, loads on the rotary bearing arrangement become so elevated that an unwanted relative rotation occurs of the structure-side and the assembly-side bearing configuration relative to one another. A relative rotation occurring in this manner may produce unwanted increased wear on at least one of the bearing configurations.
It is therefore the objective of the present invention to improve the support of the working assembly on the rotary bearing arrangement having the bearing configurations designed to be separable from one another and thereby to avoid possible increased wear.
In one embodiment the present invention achieves this objective on an earth working machine of the type mentioned at the outset in that the working assembly comprises a driver configuration having a driver surface facing in a first circumferential direction about the drive axis and that the structure-side bearing configuration has a driver counterpart configuration having a driver counterpart surface facing in a second circumferential direction about the drive axis opposite to the first, the movement spaces of the driver surface and of the driver counterpart surface about the drive axis overlapping in the reference state.
In another embodiment the present invention achieves this objective using identical means on a support structure mentioned at the outset for such an earth working machine. Since the invention is implemented on the support structure of the earth working machine and the support structure may be connected to the earth working machine in a manner that is designed to be releasable, the subsequent description and refinement of the present invention applies both to the earth working machine as well as to the support structure by itself. The support structure is preferably a casing surrounding the working assembly on multiple sides such as for example a milling drum housing known per se, which comprises a milling drum or at least a drive configuration designed for releasable coupling to a milling drum supported so as to be rotatable about the drive axis. In principle, however, the support structure may be any structure that supports the first rotary bearing and the rotary bearing arrangement.
Unless in an individual case something different is expressly stated, the present invention is described in the reference state defined at the outset, in which the working assembly is ready to rotate about the drive axis.
The maintenance, refitting and assembly purposes, for which the bearing stem and the bearing sleeve are primarily axially removable from one another, concern a maintenance and/or refitting and/or an assembly of components other than the second rotary bearing of the rotary bearing arrangement. The second rotary bearing may comprise or be a roller bearing or a slide bearing. As already stated above, the maintenance, refitting and assembly purposes concern work on the working assembly, for example the disassembly of a milling drum from a drive configuration and/or the assembly of a milling drum on a drive configuration.
Due to the arrangement of the aforementioned driver configuration and driver counterpart configuration having surfaces facing in opposite circumferential directions about the drive axis, the driver surface and the driver counterpart surface, whose movement spaces about the drive axis overlap, the driver surface and the driver counterpart surface, and consequently the driver configuration and the driver counterpart configuration, cannot pass one another along a circumferential path about the drive axis. Thus, even when the driver surface and the driver counterpart surface are at a maximum distance from one another in the circumferential direction about the drive axis when connecting the structure-side and the assembly-side bearing configurations of the rotary bearing arrangement, only a relative rotation of the two bearing configurations of less than one complete revolution is possible before the driver surface comes to engage the driver counterpart surface and the bearing configurations of the rotary bearing arrangement turn about the drive axis synchronously, and without relative turning, due to the positive engagement thus achieved. If a relative rotation of less than 360° is desired, it is possible to provide multiple driver configurations and/or driver counterpart configurations distributed over the circumference. To ensure a uniform load on the configurations, a refinement of the present invention provides for arranging just as many driver configurations as driver counterpart configurations. Preferably, a plurality of driver configurations and/or driver counterpart configurations is arranged in the circumferential direction at equal distances about the drive axis so that, when establishing the reference state, it is not necessary to mind the relative orientation of the driver configurations and the driver counterpart configurations relative to one another. For reasons of the preferred equidistant arrangement, the angular distance between two adjacent driver configurations and, respectively, driver counterpart configurations is an integral fraction of 360°.
The movement space of a surface is in this instance the space that is traversed by a surface, driver surface or driver counterpart surface, during a rotation about the drive axis.
Since normally the path of the drive torque runs from the working assembly to the structure-side bearing configuration and since further the working assembly is normally drivable only in one direction for rotation, the first circumferential direction, in which the driver surface faces, is the circumferential direction in which the working assembly is drivable for rotation.
The earth working machine preferably has a drive motor as the rotary drive of the working assembly, from which a drive torque is transmittable onto the working assembly. For driving the working assembly at a suitable rotational speed or in a suitable rotational speed range, at least one gear unit, in particular a planetary gear set, may be provided in the torque transmission path from the drive motor to the working assembly. The drive train from the drive motor to the working assembly may include a traction drive, in particular a belt drive, and the aforementioned planetary gear set, in light of space considerations preferably in the aforementioned sequence along the torque transmission path. For providing sufficient hydraulic energy, a pump power take-off gear may be additionally situated in the drive train, preferably between the drive motor and the traction drive. The final gear in the torque transmission path from the drive motor to the working assembly, in particular the aforementioned planetary gear set, may be situated, at least in sections, in a drive configuration permanently rotatably mounted by the first rotary bearing of the support structure.
As planetary gear set, the gear unit itself may include the first rotary bearing. A first part of the transmission housing may be fixed in place on the support structure and a second part of the transmission housing may be mounted on the first transmission housing part so as to be able to rotate about the drive axis relative to the first transmission housing part. The second transmission housing part may be coupled in a torsionally fixed manner to the drive configuration and/or be part of the drive configuration.
The first rotary bearing is therefore preferably a so-called locating bearing of the rotary bearing of the working assembly. As a locating bearing, the first rotary bearing has no axial clearance of motion relative to the components connected to it: the first support structure area and the working assembly. The locating bearing normally remains unchanged on the earth working machine or on the support structure over its operational life except for unavoidable wear. The rotary bearing arrangement by contrast is formed by a non-locating bearing of the rotary bearing arrangement of the working assembly, which is designed to allow for an axial relative movement between the second support structure area and the working assembly. The rotary bearing arrangement is even designed for repeated separation and reconnection of its aforementioned bearing configurations.
The structure-side bearing configuration is preferably the bearing sleeve. In order to keep the number of components low, the bearing sleeve may in principle be the inner ring of the second rotary bearing, which preferably takes the form of a roller bearing, even if this is not preferred due to the great hardness and the associated poor machinability of a roller bearing inner ring. The structure-side bearing configuration is preferably a bearing sleeve supported directly or indirectly by an inner ring of the second rotary bearing, which is preferably embodied as a roller bearing. To make it possible, preferably by a swivel movement of the second support structure area, to slide the bearing sleeve onto the bearing stem forming the assembly-side bearing configuration and to pull the bearing sleeve off the latter, the bearing sleeve is preferably designed to have a clearance tapering in the direction away from the drive axial end. The bearing sleeve is thus preferably roughly funnel-shaped. For the same reasons, the bearing stem preferably forming the assembly-side bearing configuration is preferably designed to taper in the direction of its protruding longitudinal end.
The second rotary bearing is functionally situated preferably between the second support structure area on the one hand and the two bearing configurations on the other hand so that both bearing configurations are able to rotate relative to the second support structure area.
In order to be able to avoid, during an earth working operation, unwanted ancillary forces between the driver configuration and the driver counterpart configuration having components orthogonal to a virtual circumferential circular path passing through a contact area of driver surface and driver counterpart surface, at least one surface of the driver surface and the driver counterpart surface is preferably designed to be flat. The flat surface preferably lies in a plane containing the drive axis such that it is always oriented orthogonally to its path of movement during a rotation about the drive axis. The respectively other surface of the driver surface and the driver counterpart surface may have a convexly curved shape resting on the flat surface, for example as a spherical calotte or ellipsoid calotte, or, and this is preferred for reasons of simple fabrication as well as to keep the surface pressure as low as possible, it may also be flat. To avoid unwanted high loads due to surface pressures at the contact point between the driver surface and the driver counterpart surface, the driver surface and the driver counterpart surface preferably abut in planar fashion in the abutting engagement, that is, they are parallel to one another in the abutting engagement. For this reason, the respectively other flat surface of the driver surface and the driver counterpart surface preferably also lies in a plane containing the drive axis.
Although it is possible that immediately following the establishment of a connection of the bearing configurations with one another along a circumferential circular path about the drive axis there may be a distance between the driver surface and the driver counterpart surface, an operating situation is preferred in which the driver surface and the driver counterpart surface are in an abutting engagement that transmits force in the circumferential direction. If it does not exist from the outset, this operating situation advantageously sets in by itself if there is a relative rotation between the aforementioned bearing configurations.
For securely establishing the above-described torque-transmitting abutting engagement between the driver surface and the driver counterpart surface, the driver counterpart configuration may have a depression into which a projection of the driver configuration engages. Alternatively, the driver counterpart configuration may have a projection, which is in, or may be brought into, an abutting engagement with a projection or a depression of the driver configuration. As a further alternative, the driver counterpart configuration may have both a depression as well as a projection, for example if the driver counterpart surface is formed on a separate projection component, which is inserted into a depression of the structure-side bearing configuration in order to anchor the projection component with the driver counterpart surface on the structure-side bearing configuration in a maximally durable and fixed fashion. The projection component with the driver counterpart surface may then project out from the depression beyond the surrounding surface of the bearing configuration.
The driver counterpart configuration as a projection or a depression may be formed in one piece with the structure-side bearing configuration, for example by primary forming fabrication with possible subsequent postprocessing or as a depression using only a respective machining process. In a more flexible manner and especially more suitable for retrofitting, the driver counterpart configuration may be connected as a projection component with the bearing configuration by a jointing process. Thus, the driver counterpart configuration may be connected to the bearing configuration in integral fashion, in particular by welding, possibly also by soldering or adhesive bonding, which results in a very high connection stability. Alternatively, a projection component forming the driver counterpart configuration or being comprised by the driver counterpart configuration, which comprises the driver counterpart surface, may be designed to be releasably connected to the bearing configuration, for example by bolting, so that when reaching a predetermined state of wear the projection component comprising the driver counterpart surface may be replaced with a non-worn projection component.
A high transmittable torque and a simple exchangeability of the driver counterpart surface may be achieved if the driver counterpart configuration has a projection, in particular a projection component, which is inserted into a depression in the structure-side bearing configuration and is fixated there in a manner that is designed to be releasable. Preferably, the projection or the projection component is connected to the structure-side bearing configuration in a firm, but at the same time releasable connection by bolting.
What was said above regarding the driver counterpart configuration also applies by analogy to the driver configuration. The latter may also comprise a projection and/or a depression. Accordingly, the driver configuration may also comprise a projection component, which is accommodated in a depression of the component supporting it, in order to be able to transmit a torque that is as high as possible from the - normally driving - driver configuration to the - normally driven - driver counterpart configuration.
The driver configuration may also be connected to the component supporting it in a manner that is designed to be releasable, that is, for example by bolting, or that is designed not to be releasable, that is, for example by welding, soldering, adhesive bonding and the like.
An essential difference between the driver configuration and the driver counterpart configuration is that the driver counterpart configuration is situated on the structure-side bearing configuration in order to rotate the latter synchronously with the working assembly, whereas the driver configuration does not necessarily have to be situated on the assembly-side bearing configuration, but may be situated at any suitable location on the working assembly for jointly moving with the latter. Of course, the driver configuration may be situated on the assembly-side bearing configuration.
As was already explained above, the working assembly may comprise a drive configuration, which is supported at the drive axial end by the first rotary bearing in the first support structure area so as to be able to rotate about the drive axis and which protrudes axially away from the first support structure area. A working apparatus such as a milling drum, for example, may be slid axially onto the drive configuration from the side of the retention axial end and connected to the drive configuration for joint rotation. In the same way, the working apparatus may be axially pulled off or pushed off the drive configuration in the opposite direction.
The working assembly may comprise only the drive configuration.
Since the drive configuration is permanently rotatably mounted in the first support structure area, it is advantageous if the drive configuration supports the driver configuration. The driver configuration is thus always present on the support structure and consequently on the earth working machine comprising the support structure.
Normally, in the reference state, the second support structure area is situated axially at a distance from the longitudinal end of the drive configuration that protrudes from the first support structure area. In order to be able to ensure, using little constructional effort, that the driver surface of a driver configuration situated on the drive configuration is able to come into a torque-transmitting engagement with the driver counterpart surface of the structure-side bearing configuration, it is advantageous if the drive configuration has an end face facing in the axial direction on its longitudinal end situated remotely from the first rotary bearing, the end face bearing the driver configuration. On the one hand, such an end face provides a sufficiently large area for situating a driver configuration. On the other hand, the end face, or an end face component comprising the end face, may be designed with sufficient stability for transmitting the required torques.
The end face is preferably situated orthogonally to the drive axis, although this is not necessary. The end face facing in the axial direction may also be designed to be stepped and/or conical from the drive axis radially outward, the half opening angle of the end face cone being preferably greater than 45° so as to avoid the end face having too great of an axial extension. Even then the end face still points primarily in the axial direction.
The drive configuration may comprise a tubular section, in particular a cylindrical section, whose tube or cylinder axis is the drive axis. At least a portion of the aforementioned gear unit may be situated in at least one part of this tubular section, preferably in a tubular section situated closer to the first support structure area than to the second support structure area.
On its protruding longitudinal end situated remotely from the first rotary bearing, the cylindrical section may be covered partially or preferably completely by an end face component so that the drive configuration preferably comprises a pot-like configuration, whose bottom is formed by the end face component.
As was already explained above, the drive configuration is designed to fulfill various working tasks, preferably to accommodate a milling drum in a releasably designed manner. Thus, the drive configuration is able to accommodate in temporal succession a plurality of milling drums, which differ with respect to the type and/or number and/or arrangement of the earth material-removing milling bits situated thereon. Thus, the working assembly may comprise the working configuration and the milling drum.
In order to avoid a relative rotation between the drive configuration and the milling drum accommodated by it, the drive configuration preferably has projecting transmission components, which are designed for the physical transmission of torque onto a milling drum situated on the drive configuration. Normally, torque is introduced from a drive motor of the earth working machine into the drive configuration at the drive axial end. If the milling drum is situated on the drive configuration and the working assembly comprises both the drive configuration as well as the milling drum, the torque transmission path runs within the working assembly from the drive configuration to the milling drum.
In order to keep the number of components of the working assembly as low as possible, preferably at least one of the transmission components comprises the driver configuration.
In the reference state, in particular in a reference state ready for earth working, a milling drum accommodated on the drive configuration and the drive configuration are situated coaxially. The milling drum comprises a milling drum tube, which surrounds the drive configuration radially outside. For a transmission of torque from the drive configuration to the milling drum that is as simple and secure as possible, the milling drum preferably juts out beyond the drive configuration on the longitudinal end of the drive configuration situated remotely from the drive axial end.
If the first rotary bearing is situated between the aforementioned two transmission housing parts, it is possible, for the purpose of achieving a great axial working width, for the milling drum to surround the first rotary bearing radially on the outside and to jut out beyond it in the direction away from the retention axial end.
A plurality of milling bit holders is situated on the outside of the milling drum tube, which milling bit holders are designed to accommodate milling bits. The milling bit holders are preferable designed as milling bit exchange holders having a tube-side holder component permanently situated on the milling drum tube and having a holder exchange component designed to be connected to the holder component in releasable fashion. Due to the high degree of wear to which milling bits are subject in earth working operation, the milling bits are also situated in the respective milling bit holder so as to be exchangeable. The milling bit holders are preferably arranged in spiral-shaped fashion on the milling drum tube so as to support the conveyance of removed earth material away from the working assembly.
The milling drum is preferably supported on the drive configuration on its longitudinal end situated closer to the drive axial end. This is possible there in a particularly simple and stable manner since the drive configuration at the drive axial end is supported in the support structure area and thus has a high support stiffness in that location due to the slight length of the axial protrusion from the first support structure area. For a further support of the milling drum on the drive configuration at an axial distance from the first-mentioned support, the milling drum may have at the retention axial end preferably a connecting structure running transverse to the drive axis. In the reference state, the connecting structure is preferably situated axially adjacent to the aforementioned end face so as to allow for a greatest possible bearing distance between the two support points of the milling drum. The end face of the drive configuration may comprise for example an axially protruding centering stem on which the milling drum is supported via the connecting structure in a positive fitting centered manner.
The aforementioned driver configuration supported by the drive configuration may extend axially past the connecting structure or through the connecting structure and thus protrude beyond the connecting structure to the structure-side bearing configuration. Preferably, the driver configuration extending past the connecting structure or through the latter is developed on the aforementioned transmission component. Thus, a section of the transmission component that axially overlaps with the connecting structure is able to transmit torque from the drive configuration to the milling drum and a section of the transmission component, which extends axially beyond the connecting structure to the second support structure area, is able to form the driver configuration and transmit torque onto the structure-side bearing configuration. The driver configuration is preferably an axial end of a transmission component protruding axially from the drive configuration. Such a transmission component may be embodied for example by a protruding bolt or stem. This transmission component, and the associated driver configuration, is preferably also mounted on the drive configuration in a manner designed to be releasable, for example by a bolt, in particular by a bolt passing centrally through the transmission component.
Additionally or as an alternative to the drive configuration, it is possible for the milling drum to support the driver configuration. Since the milling drum as a separate unit may be connected to the drive configuration and may be released from the latter, the present application also relates to a milling drum, as it is described and developed in this application, including a driver configuration.
If the milling drum supports the driver configuration, or at least also supports a driver configuration, the driver configuration may be situated on the aforementioned connecting structure. The connecting structure, which preferably runs transversely, as described above, particularly preferably orthogonally, to the drive axis, may connect the milling drum tube with the assembly-side bearing configuration. The assembly-side bearing configuration is preferably a bearing stem, which on the side facing away from the drive axial end protrudes axially in the direction away from the drive axial end. On the side of the connecting structure facing the drive axial end, a recess may be formed in the area of the bearing stem, into which the aforementioned centering stem of the end face of the drive configuration projects in the reference state.
The working assembly may comprise at least one retention device, for example one or several retaining bolts, by which the milling drum is retained on the drive configuration in the reference state. In order to be able to accommodate the milling drum on the drive configuration in a manner designed to be releasable, the at least one retention device is also accommodated on the remaining working assembly in a manner designed to be releasable. The driver configuration may be situated or developed on the retention device, in particular as a retaining bolt. If the retention device, in addition to a retaining bolt, comprises a washer fixated by the retaining bolt on the drive configuration and/or on the milling drum in the reference state, the driver configuration may be situated or developed, alternatively or additionally, on the washer.
In order to keep the number of components for forming the working assembly small, the retention device preferably comprises a retaining bolt, which is screwed into the aforementioned centering stem of the drive configuration in such a way that its bolt axis is coaxial with respect to the drive axis in the reference state.
In particular if the driver configuration is developed on the retention device, the driver counterpart configuration may be developed on a component developed separately of the bearing sleeve or an inner ring of the second rotary bearing, which is preferably releasably connected to the bearing sleeve or an inner ring of the second rotary bearing.
The working assembly includes all those components, which on the basis of the reference state are still connected to the drive configuration after the bearing sleeve has been pulled off from the bearing stem.
In contrast to the case discussed above, in which the driver configuration and the driver counterpart configuration are at a distance from one another in the circumferential direction about the drive axis when establishing the reference state, the case may also occur that the driver configuration and the driver counterpart configuration overlap with one another in the circumferential direction when establishing the reference state. In this case, this overlap may either prevent the establishment of the reference state as a physical barrier or the forceful attempt to establish the reference state may damage at least one of the mentioned aforementioned configurations. In order to avoid these disadvantageous consequences for the earth working machine or the support structure in the case of an overlap, there may be a provision for the driver configuration to have an alignment surface axially facing away from the drive axial end in the reference state and for the driver counterpart configuration to have an alignment counterpart surface facing axially toward the drive axial end in the reference state. The alignment surface is inclined with respect to a reference surface orthogonal to the drive axis in such a way that the alignment surface approaches the drive axial end with increasing circumferential distance from the driver surface along the second circumferential direction. The alignment counterpart surface is inclined with respect to the reference surface orthogonal to the drive axis in such a way that the alignment counterpart surface recedes from the drive axial end with increasing circumferential distance from the driver counterpart surface along the first circumferential direction. In the aforementioned case of overlap, the driver configuration and the driver counterpart configuration are able to slide past one another along their alignment surface and alignment counterpart surface by relative rotation until an axial approach of the second bearing configuration to the first bearing configuration is possible to such a degree that the reference state can be established. Under axial pressure, the alignment surface and the alignment counterpart surface force a short relative screw movement with the drive axis as screw axis upon the working assembly and the structure-side bearing configuration.
If the inclination of the surfaces, the alignment surface and the alignment counterpart surface, with respect to the reference surface is sufficiently great, no self-locking occurs, but rather, by the process of connecting the structure-side and the assembly-side bearing configurations by axial approach to one another, the working assembly and the structure-side bearing configuration are moved relative to one another out of the initially existing overlap situation. For this purpose, it is advantageous if the alignment surface is inclined with respect to the reference surface by an angle of at least 25°, preferably of at least 30°, and/or if the alignment counterpart surface is inclined with respect to the reference surface by an angle of at least 25°, preferably of at least 30°. In order to provide an abutment that is as planar as possible and has a low surface pressure between the alignment surface and the alignment counterpart surface, the angles of inclination of the alignment surface and the alignment counterpart surface are preferably equal in terms of absolute value.
As was already explained at the outset with respect to the related art, according to the present invention, the second support structure area together with the structure-side bearing configuration starting from the reference state is also swivable about a swivel axis, which is at least inclined, preferably orthogonal, with respect to the drive axis, away from the first support structure. To avoid effects of gravity on a swivel movement, the swivel axis preferably runs parallel to a yaw axis of the earth working machine extending in the vertical earth working machine direction. The swivel axis is preferably inclined by no more than 15° with respect to the yaw axis. The second support structure area is preferably developed as a maintenance door of a casing surrounding the working assembly at least for the most part, such as a milling drum housing for example.
Although the support structure may be provided on a construction site in the reference state in order to be connected to a machine frame of an earth working machine, in the reference state the support structure is preferably connected to such a machine frame. The connection of the support structure to the machine frame is preferably designed to be releasable, for example by bolting and/or actuated locking by at least one actuator-operated positive locking component, in order to facilitate the maintenance and, if necessary, repair of the support structure. It is also possible, however, for the support structure to be connected to the machine frame in a manner designed to be unreleasable, for example by welding.
The present invention will be explained in greater detail below with reference to the enclosed figures. The figures show:
In
Machine body 13 comprises front lifting columns 14 and rear lifting columns 16, which are connected at one end to machine frame 12 and at the other end respectively to front drive units 18 and to rear drive units 20. The distance of machine frame 12 from drive units 18 and 20 is modifiable by way of lifting columns 14 and 16.
Drive units 18 and 20 are depicted by way of example as crawler track units. In a departure therefrom, individual, or all, drive units 18 and/or 20 may also be wheel drive units.
The viewer of
Earth working machine 10 may comprise an operator’s platform 24, from which a machine operator is able to control machine 10 via a control panel 26.
Arranged below machine frame 12 is a working assembly 28, here represented, for example, as a milling assembly 28 having a milling drum 32, accommodated in a milling drum housing 30, that is rotatable about a milling axis R extending in transverse machine direction Q so that substrate material may be removed therewith during an earth working operation, starting from contact surface AO of substrate U to a milling depth determined by the relative vertical position of machine frame 12. Milling drum 32 is therefore a working apparatus within the meaning of the present application. The milling drum housing 30 releasably connected to machine frame 12 forms a support structure within the meaning of the present invention.
The vertical adjustability of machine frame 12 by way of lifting columns 14 and 16 also serves to set the milling depth, or generally working depth, of machine 10 in the context of earth working. Earth working machine 10 depicted by way of example is a large milling machine, for which the placement of working assembly 28 between the front and rear drive units 18 and 20 in longitudinal machine direction L is typical. Large milling machines of this kind, or indeed earth-removing machines in general, usually comprise a transport belt so that removed earth material can be transported away from machine 10. In the interest of better clarity, a transport belt that is also present in principle in the case of machine 10 is not depicted in
It is not apparent from the side view of
The driving force source of machine 10 is an internal combustion engine 39 accommodated on machine frame 12. In the depicted exemplary embodiment, milling drum 32 is rotationally driven by internal combustion engine 39. The output of internal combustion engine 39 furthermore provides a hydraulic pressure reservoir on machine 10, which makes it possible to operate hydraulic motors and hydraulic actuators on the machine. Internal combustion engine 39 is thus also the source of the propulsive force of machine 10.
In the example depicted, drive unit 18, having a travel direction indicated by double arrow D, comprises a radially inner accommodation and guidance structure 38 on which a circulating drive track 40 is arranged and is guided for circulating movement.
Lifting column 14, and with it drive unit 18, is rotatable about a steering axis S by way of a steering apparatus (not further depicted). Preferably additionally, but also alternatively, lifting column 16, and with it drive unit 20, may be rotatable by way of a steering apparatus about a steering axis parallel to steering axis S.
Milling drum 32 comprises a substantially cylindrical milling drum tube 42, on whose radially outer side bit holders or bit exchange holders 33a, having milling bits 33b exchangeably accommodated therein, are provided in a manner known per se. Of these, only one example is respectively depicted for illustration. A dot and dash line 44 indicates the effective diameter (circular cylinder section) of milling drum 32, defined by the milling bit tips of the milling bits 33b.
Working assembly 28 comprises a drive configuration 46 having an internal tube 48, a support cone 50, and part 52a, rotatable relative to machine frame 12, of a transmission housing 52. Support cone 50 and internal tube 48 are connected to one another, and are connected as an assembly to transmission housing part 52a for joint rotation about drive axis A of drive configuration 46. In the reference state of working assembly 28, drive axis A of drive configuration 46 and rotation axis R of milling drum 32 are coaxial.
In
A planetary gear set that steps speed down and steps torque up is accommodated in a transmission housing 52. The right (in
Milling drum tube 42 is braced against support cone 50 of drive configuration 46 by a negatively conical counterpart support cone 51.
Drive configuration 46 is furthermore connected to a drive torque-transmitting arrangement 54 which, in the example depicted, encompasses inter alia a belt pulley 55. Belt pulley 55 is connected to an input shaft (not depicted in
Together with the support structure-mounted assembly made up of transmission housing part 52b and shaft tunnel 56, drive configuration 46 forms a drive assembly 47 that protrudes axially into milling drum 32 from a drive axial end 28a of working assembly 28. Milling drum 32 preferably protrudes axially on both sides beyond drive configuration 46 as that part of drive assembly 47 which is rotatable relative to milling drum housing 30 as the support structure and hence to machine frame 12.
Drive assembly 47, and with it drive configuration 46, is supported on a first support structure area 30c of milling drum housing 30 in the area of shaft tunnel 56. More precisely, drive configuration 46 together with rotatable transmission housing part 52a is supported on machine frame-mounted transmission housing part 52b and hence on first support structure area 30c by a first rotary bearing 57 situated between rotatable transmission housing part 52a and machine frame-mounted transmission housing part 52b. First rotary bearing 57 is depicted in
Milling drum 32 extends axially along its rotation axis (milling axis) R, which coincides with drive axis A in the operational state, between drive axial end 28a located closer to drive torque-transmitting arrangement 54 in
At the non-locating bearing-side longitudinal end 46b located axially oppositely from locating bearing-side longitudinal end 46a, drive configuration 46 comprises a support ring 58 and an end-side cover 60 connected to support ring 58 as an end face component of the present application. In the exemplary embodiment depicted, support ring 58 is connected to internal tube 48 by welding. Cover 60 may likewise be welded, or alternatively bolted, onto support ring 58. It is connected to support ring 58 and to internal tube 48 for joint rotation about drive axis A.
Support ring 58 and the radially external areas of cover 60 may be embodied in a variety of ways. Their shape is not of essential importance. It is also conceivable to omit support ring 58 and to connect cover 60 directly to internal tube 49, in particular by welding.
In the exemplary embodiment depicted in
Hydraulic connector line 64 ends, at its longitudinal end located remotely from hydraulic cylinder 62, in a coupling configuration 68 that is connectable, in order to supply hydraulic cylinder 62, to a counterpart coupling configuration of a supply line (not depicted) so that piston rod 63 may be extended from hydraulic cylinder 62 and retracted back into it. Two hydraulic connector lines 64 may be provided in order to operate a preferred double-acting hydraulic cylinder, one for each movement direction of piston rod 63.
After the central retaining bolt 78 provided for axial positional retention of milling drum 32 on drive configuration 46 has been released, using piston rod 63 milling drum 32 may be axially pushed away from drive configuration 46 for deinstallation or pulled onto drive configuration 46 for installation.
A connecting ring 70 is arranged radially internally on milling drum tube 42 in a region located closer to retention axial end 28b, and is connected, by way of a welded joint in the example depicted, to milling drum tube 42 for joint rotation.
In the exemplary embodiment, milling drum tube 42 is rigidly connected to a connecting flange 74 via connecting ring 70 by threaded bolts 72. Connecting ring 70 and connecting flange 74 together form a connecting structure 73 of milling drum 32 mentioned in the introductory part of the specification.
Provided on connecting flange 74, bolted or welded thereto or preferably formed in one piece with connecting flange 74, is a bearing stem 74a which, starting from a connecting region of connecting flange 74 with connecting tube 70, protrudes axially toward retention axial end 28b, or away from drive axial end 28a.
Deviating from the depicted exemplary embodiment, if dimensioned accordingly, the connecting flange may be connected, in particular welded, directly to the milling drum tube without a connecting ring.
Additionally or alternatively, deviating from the depicted exemplary embodiment, the bearing stem may be formed separately from the connecting flange and be attached to the latter, in particular releasably bolted to it.
In the operational state of milling drum 32, a second rotary bearing 76 supporting drive configuration 46 for rotation about drive axis A is situated on bearing stem 74a for the formation of a non-locating bearing of the rotary bearing. In the depicted exemplary embodiment, both rotary bearings 57 and 76 are designed as roller bearings.
Together with bearing stem 74a and a bearing sleeve 86 situated on the inner ring of second rotary bearing 76, second rotary bearing 76 is part of a rotary bearing arrangement 77. Bearing stem 74a is an assembly-side bearing configuration and bearing sleeve 86 is a structure-side bearing configuration of rotary bearing arrangement 77. Together with bearing sleeve 86, second rotary bearing 76 forms a rotary bearing assembly 85 that is only movable jointly in normal operation.
Second rotary bearing 76 may be accommodated for example in a side panel or side door 30a (see
Side door 30a is preferably provided pivotably on machine frame 12 so that drive configuration 46 and/or milling drum 32 in the interior of milling drum housing 30 may be made accessible by simply pivoting open and closed. Side door 30a is preferably pivotable about a pivot axis parallel to vertical machine direction H, since the pivoting of side door 30a then does not need to occur against gravity in any pivoting direction. Rotary bearing assembly 85 is preferably supported on side door 30a in such a way that rotary bearing assembly 85 is pivotable together with side door 30a. Opening side door 30a causes rotary bearing assembly 85, that is, second rotary bearing 76 together with bearing sleeve 86, to be pulled axially off bearing stem 74a.
Preferably, the distance of the side door pivot axis from side door 30a is greater than the radius of the circular cylinder section of milling drum 32 shown in
In
Hydraulic cylinder 62, with its piston rod 63, is omitted from
Embodied on cover 60, preferably in one piece therewith, is a centering configuration 60a in the form of a centering stem which protrudes from cover 60, in a direction away from the locating bearing-side longitudinal end 46a of drive configuration 46, or from drive axial end 28a of working assembly 28, toward second support structure area 30a. Centering stem 60a protrudes into a counterpart centering configuration 74b, embodied as a centering recess, on connecting flange 74, and thereby centers milling drum tube 42, connected rigidly to connecting flange 74, with respect to drive axis A. Cover 60 comprises a central recess 60b, passing axially through it, through which piston rod 63 in
Milling drum 32 is thus braced against counterpart support cone 51 and on connecting flange 74 coaxially to drive axis A against drive configuration 46.
At the end region of centering stem 60a facing toward retention axial end 28b, recess 60b in centering stem 60a is provided with an internal thread into which the central retaining bolt 78 is threaded.
In an alternative embodiment, centering stem 60a is able to pass through connecting flange 74 and protrude axially from cover 60 of drive configuration 46. Centering stem 60a would then be the assembly-side bearing configuration.
A bolt head 78b clamps bearing stem 74a, and with it connecting flange 74 and with that in turn connecting ring 70 and milling drum tube 42, axially against support cone 50 of drive configuration 46.
When milling drum 32 is arranged axially at a distance from its operating position but still with a certain prepositioning, for example such that the longitudinal end of centering stem 60a, which is located remotely from support ring 58, is already projecting into centering recess 74b of connecting flange 74, it is thus possible to move milling drum 32 with central retaining bolt 78 axially into its operating position. Care must simply be taken that transmission components 80 in the exemplary shape of pins provided on cover 60 at a radial distance from drive axis A are able to travel into recesses 74c, provided for this purpose, of connecting flange 74, so as thereby to couple cover 60 to connecting flange 74 in order to transmit torque between drive configuration 46 and milling drum 32.
As an alternative to pulling or clamping milling drum 32 onto drive configuration 46 using retaining bolt 78, milling drum 32 can also be slid through the pivotable side door 30a onto drive configuration 46. During this sliding-on operation, not only is counterpart centering configuration 74b slid onto centering stem 60a, but rotary bearing assembly 85 is preferably also slid onto bearing stem 74a.
In order to facilitate the conveying, described in the preceding paragraph, of milling drum 32 into an operational position simply by pivoting side door 30a into its closed position shown in
Preferably the actuator is also able to assist or in fact execute the pivoting movement of side door 30a together with rotary bearing assembly 85 in an initial movement range of the pivoting movement of side door 30a out of the closed position toward the access position, the range over which rotary bearing assembly 85 is pulled off bearing stem 74a. Alternatively or additionally, the actuator may also be an electromechanical actuator.
The viewer of
All transmission components 80 and 80′ are fastened on cover 60 by a bolt 80a passing through them centrally. While a collar 80b surrounding the head of bolt 80a of unmodified transmission components 80 ends with an end face orthogonal to drive axis A, the transmission component 80′ comprising driver configuration 88 protrudes axially further from end face 60c, a circumferential section of collar 80b′ surrounding fastening bolt 80a being developed as driver configuration 88 (see also
For earth-removing work, the rotary drive described above is able to drive drive configuration 46 to rotate in only one direction of rotation, which is the first circumferential direction indicated in
In an opposite second circumferential direction U2, starting from driver surface 88a, an alignment surface 88b extends facing mainly in the axial direction, which, as shown in
Driver counterpart configuration 90 has a, preferably again flat, driver counterpart surface 90a facing in the second circumferential direction U2, which is in torque-transmitting abutting engagement with driver surface 88a. Starting from driver counterpart surface 90a, an alignment counterpart surface 90b, likewise facing mainly in the axial direction, extends in the first circumferential direction U1, which, as is likewise seen in
As driver surface 88a and driver counterpart surface 90a both point in the circumferential direction, but both in opposite circumferential directions U1 and U2, respectively, alignment surface 88b and alignment counterpart surface 90b both point in axial directions, but in opposite axial directions A1 and A2, respectively (see
The functional surfaces of driver counterpart configuration 90, the driver counterpart surface 90a and the alignment counterpart surface 90b, are formed on a projection component 90c, which is inserted as a separate component into a depression 90d in bearing sleeve 86 and is there releasably fastened, for example by three bolts. Depression 90d is a functional component of driver counterpart configuration 90.
The torque transmitted from driver configuration 88 to driver counterpart configuration 90 may be transmitted both via the fastening bolts of projection component 90c as well as via the flanks of depression 90d from projection component 90c to bearing sleeve 86 and thereby to rotary bearing assembly 85. Furthermore, depression 90d is able to provide a plane fastening surface for situating projection component 90c.
In principle, projection component 90c may also be welded to bearing sleeve 86. A releasable attachment, however, is preferable for exchanging worn projection components. Likewise, in the event of excessive wear, transmission component 80′ may be replaced quickly, simply and safely with an unworn transmission component 80′ by releasing its sole fastening bolt 80a.
The flat driver counterpart surface 90a is also preferably situated in a plane containing drive axis A.
Furthermore, as seen in
Angles α and β are respectively at least 25°, preferably at least 30°, in order to avoid self-locking in the event that alignment surface 88b and alignment counterpart surface 90b abut against one another and to ensure that if driver configuration 88 and driver counterpart configuration 90, in an attempt to establish the reference state described above and shown in
Deviating from the merely exemplary depiction in
In the second specific embodiment shown in
Driver configuration 188 comprises a projection component 188c, on which driver surface 188a and alignment surface 188b are developed and oriented in the manner described above, and which is inserted into a depression 188d of driver configuration 188 and is there fixated by bolts in a manner designed to be releasable. Depression 188d is formed in an end face of connecting flange 174.
Driver counterpart configuration 190 corresponds to driver counterpart configuration 90 of the first specific embodiment. Optionally, projection components 90c and 188c may be identical so that it is only necessary to produce a single type of projection component for forming an engagement assembly comprising a driver configuration and a driver counterpart configuration.
The remainder of the earth working machine of the second specific embodiment is unchanged compared to the one shown in
Number | Date | Country | Kind |
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10 2020 105 391.6 | Feb 2020 | DE | national |
Number | Date | Country | |
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Parent | 17171292 | Feb 2021 | US |
Child | 18300921 | US |