TREAD DEVICE FOR A CRAWLER CRANE

Abstract

The invention relates to a tread device for walking on a crawler carrier of a work machine having a caterpillar drive, wherein the tread device has a holder that can be installed at the crane, in particular at the crawler carrier, at which at least one tread surface is provided, characterized in that the tread surface lies on the upwardly disposed surface of a crawler chain of the caterpillar drive in the state installed at the work machine and the lower side of the tread surface comprises at least one sliding element to ensure a sliding or rolling relative movement between the crawler chain and the tread surface.

Claims

1. A tread device for walking on a crawler carrier of a work machine having a caterpillar drive, wherein the tread device has a holder that can be installed at the crane, in particular at the crawler carrier, at which at least one tread surface is provided, characterized in that the tread surface lies on the upwardly disposed surface of a crawler chain of the caterpillar drive in the state installed at the work machine and the lower side of the tread surface comprises at least one sliding element or roller element to ensure a sliding or rolling relative movement between the crawler chain and the tread surface.

2. A tread device in accordance with claim 1, characterized in that the sliding element is configured as a siding rail extending in the direction of travel of the work machine and the length of the at least one siding element in the direction of travel of the work machine is selected such that the sliding element extends continuously over a plurality of track pads of the crawler chain.

3. A tread device in accordance with one of the preceding claims, characterized in that the tread surface is formed by a surface section of the holder or by an element, in particular a carrier plate, supported at the holder.

4. A tread device in accordance with one of the preceding claims, characterized in that the surface of the tread surface is slip-resistant.

5. A tread surface in accordance with one of the preceding claims, characterized in that at least two sliding element are provided that are arranged in parallel with one another viewed in the direction of travel; and/or in that a plurality of individual sliding elements are arranged behind one another on the lower side of the tread surface viewed in the direction of travel.

6. A tread device in accordance with one of the preceding claims, characterized in that the tread surface is movably connected to the holder in an articulated manner thereto by at least one degree of freedom, the tread surface preferably being able to be pivotably connected to the holder in an articulated manner, in particular such that the tread surface can be flipped upward about a horizontal axis.

7. A tread device in accordance with one of the preceding claims, characterized in that the at least one sliding element comprises a softer material than the track pads of a crawler assembly, in particular plastic, preferably PA6G.

8. A tread device in accordance with one of the preceding claims, characterized in that that at least one scraping means is provided at the holder or at the tread surface to scrape off contaminants from the surface of the chain in the installation position at the crawler carrier.

9. A tread device in accordance with claim 8, characterized in that the scraping means comprises a carrier that is movably arranged at the holder and/or at the tread surface and/or comprises at least one scraper edge arranged transversely or obliquely to the direction of running in the installation position, with scraped off contaminants ideally being conveyed in the direction of the outer side by an oblique alignment of the scraper edge.

10. A tread device in accordance with claim 9, characterized in that the scraper edge has a snowplow-like arching; and/or in that a shield-like direct repeller is installed at the upper side of the scraper edge.

11. A crawler crane having a crawler assembly and at least one tread device in accordance with one of the preceding claims arranged at the crane or at the crawler assembly.

12. A crawler crane in accordance with claim 11, characterized in that the holder of at least one tread device is installed at the inner side or outer side of a crawler carrier.

13. A crawler crane in accordance with one of the claim 11 or 12, characterized in that the crane has extendable crawler carriers and the tread device is displaceable together with the crawler carrier.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0024] Further advantages and properties of the invention will be explained in more detail in the following with reference to an embodiment shown in the Figures. There are shown:

[0025] FIGS. 1a-1d: different representations of the tread device in accordance with the invention in accordance with a first embodiment variant;

[0026] FIG. 2: an alternative arrangement of the tread device in accordance with the first embodiment variant of FIG. 1;

[0027] FIGS. 3a-3c: representations of a modified embodiment of the tread device in accordance with the invention;

[0028] FIG. 4: a further embodiment of a modified tread device;

[0029] FIG. 5: a further modification of the tread device in accordance with the invention; and

[0030] FIG. 6: an embodiment variant of the scraping device of the tread device in accordance with the invention.

DETAILED DESCRIPTION

[0031] The basic idea of the tread device in accordance with the invention for walking on a crawler chain of a work machine or of a crawler crane should first be explained with reference to a first embodiment variant, shown in FIGS. 1a to 1d. The innovative tread device shown consists of a comparatively small holder that is laterally installed at the crawler carrier 1 of a crawler crane. In the variant of FIGS. 1a to 1d, it is fastened at the inner side of a crawler carrier between the undercarriage and the crawler carrier.

[0032] The direction of travel runs from left to right in FIGS. 1a and 1b. The walkable surface 8 at the holder 7 is attached via the crawler chains 5. The walkable surface 8 can be slip-resistant at its upper surface and can have a carrier plate. So that the holder 7 can be designed as very low in comparison with the known platforms, at least one sliding element 9 is provided below the walkable surface 8. The sliding element 9 supports the walkable surface 8 and takes up the normal forces introduced into the walkable surface 8 that are then transmitted into the crawler chain 5 by the sliding element 9. In general, the sliding elements 9 can be produced from a softer material than the track pads 6. A plastic such as PA6G is, for example, suitable.

[0033] The sliding element 9 is relatively long so that it lies on a large number of track pads 6 serially contiguous and can support the walkable surface 8. The holder 7 therefore substantially likewise only experiences a normal force since, unlike the solutions from the prior art, it does not have to bear any projecting platform. This permits a filigree design of the holder 7. The holder 7 is, however, also loaded in the Z direction in addition to the normal force (FIG. 3b). This results from the movement of the crawler chain 5 with respect to the sliding elements 9 and a possible drive device 50 that will be explained below.

[0034] In the embodiment of FIGS. 1a-1d, the tread device in accordance with the invention comprises two sliding elements 9 that are arranged next to one another and in parallel with one another in the direction of travel. In accordance with FIG. 1c, an embodiment is also possible with only one sliding element or with a plurality of sliding elements. The sliding element 9 here conducts the normal force into the crawler-type vehicle. The pivot connection 30 takes up the torque occurring around the sliding bearing 9. It has to have larger dimensions in the solution in accordance with FIG. 1c than in the solution in accordance with FIG. 3b.

[0035] The walkable surface 8 is movably supported at the holder 7 with at least one degree of freedom, which is implemented in the embodiment of FIGS. 1a-1d by a corresponding pivot connection 30 having a horizontal pivot axis. Additionally or alternatively, elongate holes and corresponding counter-connection means are conceivable. The movability of the sliding elements 9 and of the movable surface 8 with respect to the holders 7 is of prime importance. The track pads 6 in the crawler chain 5 move caused by contaminants, asynchronism, vertical tolerances, webs, or similar and the sliding elements 9 must be able to follow these movements without destroying any component.

[0036] To keep the addressed problem small, at least one scraping element 50 is therefore additionally provided that is supported at the tread device or at the movable surface 8 by means of a carrier 51. The carrier 51 has at least one degree of freedom about which the carrier is movable with respect to the walkable surface 8 or the holder 7 so that corresponding movements of the crawler chain can also be compensated here. A scraper edge 52 is furthermore provided at the carrier 51 to be able to scrape off the contaminants from the contact surface of the track pads of the crawler chain. The oblique position of the scraper edge 51 shown in FIGS. 1d and 4 has the result that dirt and larger stones are scraped off the track pads 6 of the crawler carrier 1 and are simultaneously conveyed outwardly from the crawler carrier 1.

[0037] Whereas the holder 7 is fastened to the inner side of the crawler carrier 1 in the embodiment of FIGS. 1a-1d, it is instead installed at the outer side of the crawler carrier 1 in the embodiment in accordance with FIG. 2. The tread surface 8 can thus be pivoted upwardly by the pivot joint 30 to thereby not block the pivot zone of the superstructure 10 about the slewing ring at the undercarriage. A use of the tread device even on cranes having an even smaller spacing 20 between the undercarriage and the superstructure can thereby take place.

[0038] In general, the solution of the tread device in accordance with the invention is conceivable at only one single crawler carrier 1 or at both crawler carriers 2 of the crawler crane. The total device requires very little construction space and can thus as a rule also remain at the apparatus in the transport state or with a set wide track of the crawler assembly and does not have to be dismantled. The crawler crane considered here can have extendable crawler carriers 1. The system of the tread device is then displaced together with the crawler carrier.

[0039] While the embodiment of FIGS. 1a-1d and 2 only shows a single sliding element 9, in the modification of FIGS. 3a-3c, the lower side of the tread surface 8 can also be designed with two sliding elements 9 arranged in parallel with one another viewed in the direction of travel. The individual lengths of the separate sliding elements 9 are here selected such that they extend over a plurality of track pads 6 in the direction of travel (see FIG. 3c).

[0040] In the embodiment of FIG. 4, not only sliding elements 9 arranged in parallel are provided, but also a plurality of sliding elements 9 arranged behind one another in the direction of travel are used. In addition in this process, a respective scraping element 50 is provided both at the front side and at the rear side of the tread device.

[0041] FIG. 5 again shows a modification of the tread device that comprises a plurality of separate tread surfaces 8 that are arranged behind one another in the direction of travel. Each tread surface is here designed with a plurality of sliding elements 9. In addition, the embodiment with two tread surfaces 8 comprises a plurality of scraping elements 50, with a first scraping element 50 being provided at the front tread surface 8 and a further scraping element 50 being provided at the rear side of the second tread surface 8.

[0042] The embodiment of the scraping elements 50 or of the scraper edges 52 is similar to that of a snowplow. The corresponding blade 52 could be adjustable and the spacing from the crawler chain could thus be variable and it thereby scrapes off any contaminants from the surface of the track pads 6. A corresponding arching of the scraper edge 52 provides a better removal of the contaminants. In addition, the blade 52 or the scraper edge 52 can extend obliquely to the rear to the left or right to remove the scraped off contaminants to the right or left.

[0043] As can be seen from FIG. 6, the scraper edge 62 can additionally be designed with a dirt repeller 53 arranged at its upper side to protect the tread surface 8 disposed behind it from the scraped off contaminants.