BAGGERAUSLEGER UND BAGGER

Abstract

The present invention relates to a boom for an earth-moving machine, in particular an excavator, comprising rear and front boom parts that are cohesively assembled to form a boomerang-like boom structure, wherein the central connection between the boom parts is formed by a simple thick central connecting plate.

Claims

1. A boom for an earth-moving machine, comprising rear and front boom parts that are cohesively assembled to form a boomerang-like boom structure, wherein a central connection between the boom parts is formed by a central connecting plate.

2. The boom according to claim 1, wherein the central connecting plate is a one-part plate or is assembled from a plurality of individual plates.

3. The boom according to claim 1, wherein the central connecting plate forms an end face of the front and/or rear boom part, wherein the central connecting plate is curved, whereby a curved contact edge of the boom parts is obtained along the boom side faces.

4. The boom according to claim 1, wherein at least one upper connecting plate is provided which forms a boom upper side in the connecting region of both boom parts and has a curved shape.

5. The boom according to claim 1, wherein the front and rear boom parts as well as the central and/or an upper connecting plate are welded together.

6. The boom according to claim 1, wherein the front and/or rear boom part have a box structure with a rectangular cross-sectional profile.

7. The boom according to claim 1, wherein the cross-sectional profiles of the boom parts are different in the connecting region.

8. The boom according to claim 1, wherein one or more bearing points for at least one actuator are arranged directly on the central connecting plate, wherein bearing points are formed by a tube for accommodating a bearing bolt extending through boom side faces transversely to the longitudinal boom axis.

9. The boom according to claim 8, wherein in the region of the outlet openings of the tube reinforcing plates are provided on the side faces, wherein the reinforcing plates and/or the tube is/are manufactured as a common casting or machined part.

10. The boom according to claim 1, wherein on an upper connecting plate one or more bearing points are provided for accommodating an actuator for actuating a boom extension and/or an attachment, wherein the at least one bearing point comprises at least two bearing plates at least sectionally arranged parallel to each other, which are welded perpendicularly to the upper connecting plate, and wherein these bearing plates diverge towards the end in the longitudinal direction of the boom.

11. An earth-moving machine with at least one boom comprising rear and front boom parts that are cohesively assembled to form a boomerang-like boom structure, wherein a central connection between the boom parts is formed by a central connecting plate.

12. The boom according to claim 1, wherein the earth-moving machine is an excavator.

13. The boom according to claim 5, wherein the front and rear boom parts and the central and/or upper connecting plate are welded together by fillet welding.

14. The boom according to claim 7, wherein the cross-sectional area of the front boom part is larger in area than the cross-sectional area of the rear boom part.

15. The boom according to claim 8, wherein the at least one actuator is a luffing cylinder, wherein the actuator is welded on the central connecting plate, and wherein tube openings exit through the side faces of the rear boom part.

16. The boom according to claim 10, wherein the actuator is a cylinder unit.

17. The earth-moving machine according to claim 11, wherein the earth-moving machine is an excavator.

Description

[0020] Further advantages and properties of the invention will be explained in detail below with reference to an exemplary embodiment illustrated in the Figures, in which:

[0021] FIG. 1: shows a perspective top view of an excavator boom according to the invention;

[0022] FIG. 2: shows a detail view of the connecting point between the front and rear excavator boom parts; and

[0023] FIG. 3: shows a detail view of the connecting region of FIG. 2 with an open side face of the boom arm.

[0024] The perspective side view of FIG. 1 shows the total construction of the excavator boom 10 according to the invention. The same consists of a front boom part 11 and a rear boom part 12. At the front boom part connecting points 34 are provided for movably mounting a non-illustrated attachment or a boom extension. The rear boom part 12 comprises corresponding bearing points 16 at its end in order to be able to luffingly articulate the same to an excavator uppercarriage or undercarriage.

[0025] Both the rear and the front boom part can be fabricated as a monoblock. It is likewise possible, however, to assemble the boom parts 11, 12 from individual elements.

[0026] Both boom parts 11, 12 have a box-shaped structure that is obtained by welding together corresponding side plates. The individual side plates 11a to 11d and 12a to 12d are welded together by a fillet welding method.

[0027] The connection between the two boom parts 11, 12 is created by the central connecting plate 13, wherein at least the front edges of the side plates 11a, 11b and 12a, 12b and possibly of the undersides 11d and 12d are cohesively connected to each other via the connecting plate 13. The connecting plate 13 has a curved shape, whereby possibly a curved contact edge of the boom parts 11, 12 is obtained along the side plates 11a, 11b, 12a, 12b. The connecting plate 13 is designed as a simple, thick plate. It allows a simple connection between the boom parts 11, 12 and correspondingly a simple adaptation to the desired angle that is formed by the two boom elements 11, 12. In addition, it is also possible to flexibly react to the desired width of the box-shaped boom parts 11, 12, i.e. the width of the respective side faces 11c, 12c. The construction according to the invention leads to a distinct reduction of the incurred manufacturing costs and the resulting total weight of the boom 10.

[0028] In the region of the boom upper side the boom surfaces 11c and 12c of the boom parts 11, 12 are not directly connected with each other. Instead, a plate-shaped upper connecting plate 15 is inserted here or overlappingly placed on the upper sides 11c, 12c and welded to the two boom parts 11, 12. The plate-shaped upper connecting plate 15 is bent corresponding to the angle formed by the two boom parts 11, 12 relative to each other. Possibly, the boom underside might also be designed with a corresponding connecting element.

[0029] In the region of the rear boom part 12 a cylindrical tube 21 extends through the boom box 12 transversely to the longitudinal boom axis, which is welded to the central connecting plate 13. Mounting the bearing tube 21 on the central connecting plate 13 at the same time ensures that the total stiffness of the boom can additionally be increased. Via outlet openings 21a, 21b within the side elements 12a, 12b an appropriate bolt can be put into the cylinder tube 21. In the region of the outlet openings 21a, 21b additional reinforcing plates 22 are also mounted on the outside of the side plates 12a,12b. The tube 21 forms the bearing point for the connection of a luffing cylinder of the excavator according to the invention, which extends from the bearing point 21 of the rear boom part 12 to the uppercarriage of the excavator.

[0030] For supporting a further hydraulic adjusting means in the form of a hydraulic cylinder an additional bearing point 30 is provided on the upper side of the boom 10, which provides for accommodating a cylinder that extends from the bearing point 30 up to an attachment accommodated at the bearing point 13.

[0031] The bearing point 30 consists of two bearing plates 30a, 30b extending in parallel, which are perpendicular to the boom upper side and extend parallel in the longitudinal direction of the boom. In the region with the largest width, a bore 31a, 31b each is provided for accommodating a bolt, wherein the bore edge is reinforced with additional plates 32. The width of the bearing plates 30a, 30b steadily decreases in the direction of the rear boom part 12. The majority of the bearing plates including the bores 31a, 31b are arranged on the upper side 11a of the front boom part 11, but both plates 30a, 30b extend in parallel except for the upper connecting plate 15 to which the plate ends are welded. The extension of the bearing plates 30a, 30b up to the connecting plate 15 has the advantage that the end of the formed welding seam lies in a region of the boom to which less force is applied, whereby not only the material fatigue resistance can be increased, but manufacturing costs also can be lowered, as in this case no additional aftertreatment of the welding seam is necessary.

[0032] Furthermore, it can be seen that the width of the bearing plates 30a, 30b after the bore 31a, 31b abruptly decreases in the direction of the boom tip and then remains almost constant. These bearing plate portions 33a, 33b of reduced, but almost constant width have a curvature so that the plate portions 33a, 33b do not extend parallel to each other, but outwardly to the edges of the surface 11c of the front boom part 11.

[0033] The upper plate 11a of the front boom part 11 can be broadened in the region of the bearing plate portions 33a, 33b adjoining the edge so that the plate elements 33a, 33b can protrude beyond the actual edge of the front boom part. Due to the bend of the bearing plates 30a, 30b the total stiffness of the bearing can be increased, but without having to increase the thickness of the bearing plates 30a, 30b. In addition, it is not necessary either to mount further reinforcing plates in the region of the bearing point. Thereby, the total weight of the boom can further be reduced and its manufacture can further be simplified.