The invention is explained in more detail in the following on the basis of an exemplary embodiment which is schematically illustrated in the drawing, in which:
FIG. 1 shows a perspective view of a working device for a digger having a digging scoop and an add-on device;
FIG. 2 shows a perspective view of an exchangeable auxiliary tool for the add-on device;
FIGS. 3 and 4 show, in a vertical section perpendicular to the pivoting axis, the working tool from FIG. 1 with the auxiliary tool in the opened and closed pivoting positions,
FIGS. 5 and 6 show, in a partially sectioned side view and a partially sectioned plan view, a further embodiment of an auxiliary tool to be connected to a pivoting shaft;
FIGS. 7 and 8 show a cleaning scraper as an auxiliary tool in the detached and pivoted-in positions in combination with the digging scoop.
The working tool illustrated in the drawing is composed substantially of a deep scoop as a digging device 10 and an add-on device 12, which is arranged as a modular unit on said digging device 10, for an exchangeable auxiliary tool 14, 16, 17.
The scoop 10 has a receiving space 24, which is delimited by side walls 18, an upper wall 20 and a lower wall 22, for the excavated material. To assist the digging process, a plurality of teeth 28 is arranged at a free edge 26 of the lower wall 22. Two mounting brackets 30 are provided on the upper delimiting wall for a pivoting connection, which is known per se, to an arm of a digger (not illustrated). The mounting brackets 30 have mounting eyes 32 for holding an arm pin and bores 34 for coupling on a drive piston.
The add-on device 12 comprises a pivoting drive 36 which is embodied as a hydraulic cylinder and is supported at the cylinder side in mounting brackets 38 on the upper delimiting wall 20 of the scoop 10. At the linkage end of its piston rod, the hydraulic cylinder 36 is fixedly connected to a pivoting shaft 42 by means of an angled pivoting lever 40.
The pivoting shaft 42 runs parallel to the arm pin (mounting eyes 32) provided on the arm for a pivoting movement of the scoop 10. Said pivoting shaft 42 extends between the side walls 18 over the full width of the scoop opening 43 in the upper edge region thereof. As can also be seen from FIGS. 3 and 4, the pivoting shaft is formed by a tube 44 which is rotatably mounted on a fixed inner axle rod 46 and is axially supported at each of its ends against a collar 48 of the axle rod 46.
FIGS. 1 and 2 illustrate, by way of example, gripping fingers 14 and a flap-like sorting sieve 16 as auxiliary tools. The auxiliary tools 14, 16 can be rotationally fixedly connected to the pivoting shaft 42 by connecting means 50 for a pivoting movement. The connecting means 50 comprise a plurality of screw lugs 52, which are welded to the pivoting shaft 42 so as to be distributed at a distance from one another in pairs, for a screw connection 54 in combination with a positively locking connection 56 of the auxiliary tools 14, 16 to the pivoting shaft 42. This makes it possible to quickly exchange the auxiliary tools 14, 16 according to the desired working application.
It is fundamentally also possible, by means of a profiled element of the pivoting shaft, to provide any desired connecting points for the auxiliary tools to be axially plugged on, or suspended by means of their casing, in a positively locking and rotationally fixed manner.
In order to be capable of better withstanding the forces which act on the scoop 10, the latter is reinforced in the region of its upper wall 20 at the inside by means of a stiffening element 58 which is embodied as an angled plate.
The coupling of the scoop 10 to the digger arm by means of the mounting brackets 30 does not require any assembly work of the hydraulic cylinder 36. It is necessary only to provide the hydraulic connections for the latter by means of suitable lines. An actuation of the hydraulic cylinder 36 causes the toothed gripping finger 14 to pivot relative to the scoop 10 or the receiving opening 43 thereof (FIGS. 3, 4), so that for example tree trunks or stone chippings can be captively held. By using a sorting sieve as per FIG. 2, it is possible for small parts of the excavated material to be discharged from the receiving space 24 of the scoop 10 via the free intermediate spaces 60 of said sorting sieve, while relatively large parts are retained. It would also be correspondingly possible to use a sludge flap for filtering out liquid constituents. Here, said connecting means 50, as a quick-exchange system, permit a quick exchange with little manual expenditure.
FIGS. 5 to 8 show a further embodiment of the connecting means 50. Radially protruding plug-in spigots 70 are welded to connecting points provided for this purpose, while the auxiliary tool 14, 17 has a corresponding receiving shoe 72 which can be placed in a clamped manner onto the plug-in spigot 70 and can be fixed thereon by means of a securing pin 73 which can be screwed in from the side. The gripping finger 14 shown in FIG. 5 is provided with a detachable toothed rail 74 in order to be better capable of retaining the material to be gripped, for example tree trunks.
In the exemplary embodiment shown in FIGS. 7 and 8, a cleaning device 17 for scraping out the receiving space 24 is provided as an auxiliary tool 17. It is also possible here to provide a quick-exchange connection by means of plug-in spigots 70 on the shaft and receiving shoes 72 on the tool. The cleaning device 17 is formed by two flat scrapers 76 which are arranged at a lateral distance from one another and are guided along so as to scrape the inner surfaces of the side walls 18 in order to scrape off any stuck-on dirt. The flat scrapers 76 have a curved cutting edge 78 which, as it advances in the pivoting-in direction, sweeps across almost the entire lateral inner surface. It has surprisingly been shown that this is entirely sufficient for effectively cleaning the inner space 24.
Patent Application
20080016729
