Patent Application
20080264755
The invention relates to a roller conveyor for transporting goods carriers, in particular “skids” in the automotive industry, comprising
Such roller conveyors are used for transporting goods carriers, such as for example pallets. In the automotive industry, vehicle bodies or parts of vehicle bodies are frequently transported thereby between individual operating stations. The vehicle bodies are in this case fastened to so-called “skids”. Transport frames are denoted thereby which have two skid runners parallel to one another. The skid runners bear on rollers of the roller conveyor during the conveying process, which are arranged in pairs and in series in the direction of conveyance. If the rollers are set in rotation by drives, the skid is conveyed with the vehicle body fastened thereto in the direction of conveyance.
The known roller conveyors are made up of individual roller path modules, which respectively contain a separate electrical drive motor. The drive motor is generally arranged between parallel roller strips, in which the rollers are accommodated. Generally, the torque generated by the drive motor is distributed via belts to the driven rollers of one of the two roller strips. Said rollers are rigidly connected via axles to the rollers on the other roller strip.
Frequently, such roller conveyors have operation units which are movable relative to the conveyor path. Generally in this connection said operation units are longitudinal or transverse sliding carriages or turntables or swivel tables. By means of such operation units, it is possible for example to link a plurality of conveyor paths together in the manner of a network or to distribute goods carriers to storage points as in a shunting yard.
The operation units were hitherto individually constructed devices comprising a running gear in addition to driven, and possibly also non-driven, transport rollers, in order to be able to move the operation unit relative to the conveyor path.
It is the object of the invention to improve the variability and modularity of the known modular roller path systems.
This object is achieved in a roller path system of the aforementioned type, in that the operation unit is constructed from a roller path module and running gear modules fastened thereto. The running gear modules may in this case be fastened to the roller path module directly or via intermediate members. Such intermediate members may, if required, also be regarded as detachable components of the running gear modules.
According to the invention, the operation unit is thus no longer constructed as a relatively complex complete unit, but constructed on the basis of a roller path module used is for the conveyor paths. By fastening the running gear modules to the standard roller path modules, more complex operation units such as turntables or swivel tables as well as longitudinal and transverse sliding carriages may therefore be constructed in a simple manner. This considerably simplifies the construction, the storage of individual parts and also the assembly of the roller conveyor. The upgrading of a standard roller path module into a more complex operation unit is even possible at the point of operation of the roller conveyor.
In order to allow the mobility of the operation unit, the running gear modules have devices which allow a movement relative to the fixed conveyor paths. Said devices may, for example, be linear ball bearings or electromagnets, which allow a contactless suspension of the operation unit in a similar manner to magnetic levitation railways.
However, it is particularly simple and cost-effective if the running gear modules have rollers on which the entire operation unit may be moved on a suitable base or on rails. The arrangement and alignment of the rollers on the running gear modules determines, therefore, how the entire operation unit is able to move.
If the rollers of the running gear modules have, for example, rotational axes which extend parallel to the longitudinal direction of the roller strips, the operation unit is therefore a transverse sliding carriage which may be moved transversely to the longitudinal direction of the roller strips.
If the rollers of the running gear modules, however, have rotational axes which extend at right angles to the longitudinal direction of the roller strips and parallel to a conveying plane predetermined by the roller strips, a longitudinal sliding carriage is created from the roller path module which may be moved in the longitudinal direction of the roller strips.
In principle, with rotational axes of the rollers arranged longitudinally or transversely to the longitudinal direction of the roller strips, turntables or swivel tables may also be constructed. An improved support and more advantageous running properties are, however, achieved if the rollers of the running gear module fastened to the roller path modules have rotational axes which extend parallel to a conveying plane predetermined by the roller strips and obliquely to the longitudinal direction of the roller strips. Furthermore, the roller path system may comprise curved runners for the rollers as further modules. The radius of the runners may in this case be relatively large, as a result of which an effective support of the turntable or swivel table is ensured.
If the running gear modules are releasably connected to the roller path module, therefore, there is the possibility of converting operation units into different operation units by retrospectively exchanging running gear modules. As a result, the roller conveyor may be converted in a simple manner at the point of operation, in order to take account of changed requirements. Roller path modules and possibly also running gear modules which are already present may also be possibly used again with such a conversion.
It is most advantageous if in the operation unit the running gear modules are fastened to the roller path module such that they have the same spacing from the front faces thereof. In this manner, a symmetrical arrangement is achieved which ensures a uniform force distribution. Such a symmetrical arrangement is even obligatory when constructing turntables. Advantageously such a symmetrical arrangement may also be provided with regard to additional parts such as covers, or the like, which also may be provided in standard sizes.
In accordance with a force distribution which is as advantageous as possible, in the operation unit, the running gear modules should be fastened to the roller path module such that they extend parallel to a plane fixed by the roller strips, outwardly away from the roller path module.
Structurally, it is simplest if in the operation unit, the running gear modules are fastened to side cheeks of the roller strips. As an alternative, however, the running gear modules may also be fastened beneath the roller strips.
In order to simplify the assembly of the operation unit at the point of operation, stops for aligning the running gear modules or intermediate members connected thereto may be configured on the roller path modules.
If the roller strips are connected to one another in the transverse direction by transverse members, there is the possibility in the operation unit of fastening the running gear modules to the ends of the transverse members.
It is even more advantageous if the roller strips have through-passages which extend transversely to the longitudinal direction of the roller strips. Crossmembers which are connected to the running gear modules may be inserted into the through-passages.
If a transverse member is present between the roller strips, said transverse member may advantageously be arranged between opposing through-passages of the roller strips, such that it is used as a stop for such a crossmember. The transverse members themselves are preferably releasably connected to the roller strips. This is advantageous as the roller path modules made up of smaller sub-assemblies, namely the roller strips and the transverse members, may be assembled at the point of operation of the roller conveyor. Thus it is possible to assemble roller path modules which, due to their transport volume, would only be able to be transported with greater difficulty to the point of operation.
A particularly good stop effect is achieved if the transverse members have a hollow profile or U-shaped profile, into which the crossmember is inserted.
In a particularly advantageous embodiment of the invention, in the operation unit respectively two running gear modules are fastened to one crossmember which extends at least over the entire width of the roller path module and is accommodated in the through-passages of the roller strips. The transverse member thus represents an intermediate member to which the running gear modules may be fastened.
In this embodiment, two running gear modules may be very easily fastened to the roller path module at the same level in a manner such that the crossmember is initially passed through the through-passages. The crossmember, therefore, preferably bears against suitably configured stop surfaces on the roller strips and may be fastened in this position by screw connections or in any other manner to the two roller strips. Subsequently, the two running gear modules are fastened to the inserted crossmembers and namely preferably to the free ends thereof. In this manner, the running gear module may be fastened to a roller path module in a manner which is very stable and may be rapidly assembled.
In this embodiment, the crossmembers and/or the roller strips may preferably be configured as U-shaped profiles. As a result, the entire operation unit obtains a very torsionally rigid and nevertheless lightweight construction.
U-shaped profiles have, moreover, the advantage that the inside of the profiles is more easily accessible, in order to attach screw connections and the like or to lay electrical cables. It is also advantageous from the last-mentioned point of view if the U-shaped profiles of the roller strips are arranged such that their open side faces upwardly. This open side may, if required, be closed by covers, after all assembly operations which require access to the inside of the profiles are completed.
Covers may, however, also be fastened to the roller strips which cover the entire space between the roller strips and which preferably all have the same dimensions.
The covers may in the longitudinal direction of the roller strips have dimensions which substantially correspond to the spacing between the transport rollers. So that the same covers may also be used at the joins between the adjacent roller path modules, the spacing between the transport rollers should be double the size of the spacing between the front faces of the roller path modules and the last transport rollers on the front face.
The modular construction of the roller conveyor comes to bear particularly advantageously if the roller conveyor has a plurality of different operation units which are constructed on the basis of the same roller path module, and differ from one another substantially only by the running gear modules fastened thereto. As, as already mentioned, the mobility of the operation units is finally only established by the arrangement of the rollers relative to the roller strips, it is sufficient in principle to configure the running gear modules as simple holders, in which rollers are held with different orientations. These holders may, therefore, if required, be connected via additional intermediate members to the roller strips.
A further differentiation of the running gear modules may be made from the point of view of whether the rollers are driven or not driven. When using hub drives, the same holders may be used both for driven and for non-driven rollers. In this manner, the modularity of the entire system is further increased.
The construction of the roller strips is considerably simplified if each driven transport roller has its own drive, for example in the form of a hub drive. The relatively costly and maintenance-intensive use of belts for transmitting the drive torques between adjacent rollers may therefore be dispensed with.
In order to allow an automatic movement of the roller path module in the movement plane, at least one roller of an operation unit should have a separate drive. Preferably, in this case it is also a hub drive. Such a hub drive makes it possible both for the rollers and for the transport rollers to use identical sub-assemblies consisting of a roller and a hub drive. This allows in turn a very compact and modular construction of the entire operation unit.
When using the same sub-assemblies for the transport rollers and for the rollers, the power supply and control of the rollers may also be carried out in the same manner. Thus all roller sub-assemblies may be connected to the same power supply and the same control device.
Preferably, these roller sub-assemblies may be connected to one another such that on the front faces of the roller path modules respectively one single electrical connection is present for the power supply of all drives and a single connection is present for controlling the drives. These connections may, therefore, be connected to the connectors of a roller path module adjacent thereto. The connection is particularly simple when the connectors are configured as releaseable connections.
It is also advantageous if each roller path module has at least two driven transport rollers. If the skids are not substantially shorter than the roller path modules, in this manner it is ensured that every skid at any point in time bears on at least two driven transport rollers. If one of the transport rollers fails, the remaining transport roller is at least able to convey the skid in an emergency operation.
The subject of the invention is also a roller path system which may be used for constructing a roller conveyor, as has been described above. The modular roller path system comprises a plurality of roller path modules, from which a conveyor path may be constructed by arranging along a line. The roller path modules respectively comprise two roller strips parallel to one another and contain at least one driven transport roller. According to the invention, additional running gear modules are provided from which an operation unit may be constructed which is movable relative to the conveyor path, by fastening to a roller path module.
If the roller path system comprises different sets of running gear modules, different operation units such as longitudinal and transverse sliding carriages or turntables and swivel tables may be constructed by fastening the running gear modules to a roller path module.
Overall, therefore, a modular roller path system is provided in which from a few modules complex roller conveyors including corresponding operation units such as turntables and swivel tables and longitudinal and transverse sliding carriages may be constructed.
Further features and advantages of the invention are revealed from the following description of an embodiment with reference to the drawings, in which:
In
The same applies also to the non-driven transport rollers 16a except that said non-driven transport rollers do not have a hub drive.
The profiles of the driven transport rollers 14a may have a different form from the profiles of the non-driven transport rollers 16a. In particular it is advantageous if the driven transport rollers 14a are provided with a coating which generates a high degree of friction.
The hub drives of the driven transport rollers 14a are connected to one another via a common power supply unit, but may be controlled individually via a control bus.
Preferably the cables for the power supply and the control bus run within the roller strip 12a and at the free ends of the roller strips 12a feed into suitable is plug contacts (not shown), in order to allow a simple connection to adjacent roller path modules.
The other roller strip 12b is designed in a similar manner, except that the driven transport rollers 14b are arranged offset to the driven transport rollers 14a of the roller strip 12a such that a driven transport roller 14a, 14b respectively opposes a non-driven transport roller 16b and/or 16a at the same level in the longitudinal direction LR.
The arrangement described above of the driven and non-driven transport rollers is only given by way of example. Generally, this arrangement of roller conveyors primarily depends on the type and dimensions of the goods carriers to be conveyed, the weight of the objects to be transported thereon and also on the drive power of the roller drives. With the skids located in this case in the foreground, other arrangements are also considered. Thus instead of the offset arrangement the driven transport rollers may also be arranged respectively parallel, i.e. located at the same level. More or fewer non-driven rollers may also be present than has been described above.
The two roller strips 12a, 12b are rigidly connected to one another via two transverse members 18, 20. The transverse members 18, 20 are welded to the roller strips 12a, 12b or fastened in a different manner, for example by screw connections. In the embodiment shown in
In the embodiment shown the entire roller path module 10 is fastened to floor members 26a, 26b, which encompass the roller strips 12a, 12b from below. The floor members 26a, 26b are fastened to an assembly base or a similar supporting structure and may be adjusted heightwise for compensating for floor unevenness.
For constructing a roller conveyor, a plurality of roller path modules 10 are arranged in series. Then the electrical connections at the ends of the roller strips 12a, 12b are connected to the corresponding connections of the adjacent roller strips 12a, 12b. Subsequently, the roller strips 12a, 12b of the adjacent roller path modules on the front face are connected to one another, for which for example guide shoes may be used which may be inserted into the hollow profiles. In a further step, the floor members 26a, 26b are fastened in their final position according to the exact alignment of the roller path modules and leveled heightwise. After the connection of the roller path modules 10 to a power supply unit and to a control unit, it is possible to carry out the conveying operation. In this manner, a roller conveyor may be constructed very rapidly and with low assembly costs at the point of operation, which may be converted in a versatile manner due to its modular construction.
The objects to be conveyed by the roller conveyor may, in particular, be skids which in turn carry motor vehicle bodies or preassembled motor vehicles. The skids are provided on their underside with runners with which they bear against the driven and non-driven transport rollers 14a, 14b and/or 16a, 16b. The runners of the skids are in this case sufficiently long that they always bear on at least two transport rollers, preferably on three or even four transport rollers. By the alternate arrangement of the driven and non-driven transport rollers 14a, 14b and/or 16a, 16b it is ensured that, in this layout, each runner of the skid is always driven by at least one transport roller. It has proved advantageous if the roller path modules 10 have a total length which is slightly greater than the length of such skids. With a skid length of 5 metres, the roller path module 10, for example, may have a length of 6 metres.
As has already been mentioned, the channels 22, 24 running at the same level as the transverse members 18, serve to receive crossmembers with which the roller path modules 10 may be further extended and converted into different operation units. Hereinafter, different possibilities are described with reference to
In
The connecting flanges 30a, 30b may, however, also be used for fastening rollers 32a, 32b which are held in holders 33a, 33b. The holders 33a, 33b for the rollers 32a, 32b have mating flanges 34a, 34b which are screwed to the connecting flanges 30a, 30b of the crossmembers 28a, 28b. The rollers form, together with the holders 33a, 33b, running gear modules which may be screwed as preassembled units to the connecting flanges 30a, 30b.
In the case shown in
The entire unit shown in
Also in this case, again two or even a plurality of rollers 30a, 30b may use a single drive as is also the case in the embodiment shown in
At the opposite end of the swivel table 400 the connecting flanges 30a, 30b carry holders 433a′, 433b′ for rollers 432a′ and/or 432b′, the rotational axes thereof in this case, by way of example, enclosing an angle of ±15° relative to the longitudinal direction LR of the roller strip 12a, 12b. These two outer rollers 432a′, 432b′ run on an approximately semi-circular second runner 40b which is arranged concentrically to the first runner 40a.
In the swivel table 400 a pair of opposing running wheels, for example the outer pair 432a′, 432b′ are also provided with separate hub drives so that the swivel table may be swiveled about the centre point of the first runner 40a.
The roller path module 10′ has two roller strips 12a′, 12b′ which are arranged parallel to one another. As may be seen best in the cross section of
The driven transport rollers 14a′ are, as in the embodiment shown in
The two vertical side limbs of the roller strip 12a′ also have two through-passages, the spacing thereof being identical from the front faces of the roller strip 12a′. As may be seen in
The other roller strip 12b′ is configured in the same manner, in this case the driven transport rollers 14a′, 14b′ also being arranged offset to one another, as is also the case in the roller path module 10 shown in
In the through-passages located at the same level in the roller strips 12a′, 12b′ transverse members 18′, 20′ are inserted such that the free ends of the transverse members 18′, 20′ project over the outer limbs of the roller strips 12a′, 12b′, as is best visible in
Holders for rollers may be fastened to the outwardly projecting front faces of the transverse members 18′, 20′, in order to construct operation units on the basis of the roller path module 10′, as are shown from the principle in
If the roller path module 10′ is not intended to be part of an operation unit, as shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2005 047 530.2 | Oct 2005 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2006/009366 | 9/27/2006 | WO | 00 | 5/7/2008 |
