Work Machine Having a Hood to Cover or Open an Opening

Abstract

A mobile work machine has a loadbearing frame and a drive unit. A covering unit can be moved for into and out of a covering position covering a loadbearing frame opening for covering the drive unit. At least one closure unit for selectively holding the covering unit in a closure position has at least one first closure element and one second closure element which can be adjusted along an adjustment path relative to the first closure element. The closure unit has at least one obstacle to be overcome during the relative adjustment of the first and second closure element. The obstacle defines a release path during opening which is oriented in the direction of the adjustment path and, defines a fixing path during closing which is oriented in the direction of the adjustment path. The release path for the opening is greater than the fixing path.

Claims

1. A mobile work machine comprising: a loadbearing frame; a drive unit for driving a driven device including at least one drive element and/or at least one work element; at least one covering unit which can be moved about a pivot axis from a closure position that covers an opening in the loadbearing frame to cover the drive unit to an open position exposing the opening to render the drive unit accessible through the opening; at least one closure unit that is configured to hold the covering unit in the closure position, the closure unit having at least one first closure element and one second closure element which can be adjusted along an adjustment path relative to the first closure element, the closure unit having at least one obstacle that must be overcome during the relative adjustment of the first and second closure elements, with the result that, during an opening movement of the covering unit, the obstacle defines a release path which is oriented in the direction of the adjustment path and that, during a closing movement of the closure unit, defines a fixing path which is oriented in the direction of the adjustment path, wherein the release path is greater than the fixing path.

2. The work machine as claimed in claim 1, wherein the fixing path extends from an initial contact position to the closure position, the initial contact position being configured as a first contact position in the direction of the adjustment path, and wherein the release path for the opening extends from the closure position to an end contact position, the end contact position being configured as a last release contact position in the direction of the adjustment path during the opening movement of the closure unit.

3. The work machine as claimed in claim 1, wherein the first closure element comprises at least the obstacle, and wherein the obstacle is configured as a projecting portion of the first closure element.

4. The work machine as claimed in claim 1, wherein at least one of the obstacle and the projecting portion is oriented at least partially in the direction of the fixing path, and wherein an acute angle is provided between the fixing path and a longitudinal axis of at least one of the obstacle and the projecting portion.

5. The work machine as claimed in claim 1, wherein the first closure element is configured as an elastically deformable elastomer element.

6. The work machine as claimed in claim 1, wherein the first closure element has at least one elastically deformable barb.

7. The work machine as claimed in claim 3, wherein a first cross section of at least one of the obstacle and the projecting portion is of smaller configuration than the second cross section of a second portion of the first closure element.

8. The work machine as claimed in claim 1, wherein the second closure element has a square cross section.

9. The work machine as claimed in claim 1, wherein at least two first closure elements are arranged on the covering unit.

10. The work machine as claimed in claim 1, wherein the second closure element is arranged between two first closure elements.

11. The work machine as claimed in claim 1, further comprising a single-piece closure element structural unit comprising at least two first closure elements.

12. The work machine as claimed in claim 1, wherein at least one prestressing unit is provided for at least one of prestressing the closure unit and for generating a prestressing force which acts on the first closure element or the covering unit.

13. The work machine as claimed in claim 1, wherein at least one of the first closure element and the second closure element is arranged on an edge portion of the covering unit.

14. The work machine as claimed in claim 1, wherein at least one of the first closure element and the second closure element is arranged on an edge portion of the covering unit, which edge portion lies opposite the pivot axis.

15. The work machine as claimed in claim 1, wherein the covering unit is configured as a motor hood or as a cabin door.

16. The work machine as claimed in claim 1, wherein the work machine comprises one of a wheel loader, a telescopic handler, an excavator, a tractor, and a soil compaction apparatus formed from one of a vibratory rammer and a vibratory plate.

17. The work machine as claimed in claim 1, wherein the driven device comprises 1) a drive element comprising a least one of a drive wheel/roller, a crawler track unit, and a vibratory element, and/or 2) a work element comprising at least one of a gripping arm, a scoop, a fork, a vibratory element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] One exemplary embodiment of the invention is shown in the drawing and will be explained in greater detail in the following text on the basis of the drawing figures, in which, in detail:

[0044] FIGS. 1A and 1B show a diagrammatic, partially sectioned detail of a first closure variant in accordance with the invention in a closure position and in a partially open position,

[0045] FIG. 2 shows a diagrammatic cross section through the second closure variant in accordance with the invention, and

[0046] FIGS. 3AA-3BD show a diagrammatic cross section of the third closure variant in accordance with the invention in various positions of closing and of opening.

DETAILED DESCRIPTION

[0047] In FIGS. 1A and 1B, a detail of a covering unit 1 or motor hood 1 can be seen diagrammatically in a closure position (cf. FIG. 1A)) and in a partially open position (cf. FIG. 1B)). Here, the motor hood 1 closes an engine opening 2 during operation, and makes opening and possibly maintenance of the drive engine which is not shown in greater detail or the like possible.

[0048] A closure 3 comprises firstly a so-called second closure element 5 which is arranged fixedly on the loadbearing frame of a mobile work machine such as a vibrator or the like, or a square tube 5 which can be brought into an operative connection with a rubber element 4 or elastic element 4 or so-called first closure element 4 in accordance with the invention. This rubber element 4 has a lug 7 or a projection 7 or a barb 7, whereby the motor hood 1 is secured effectively in the closure position according to FIG. 1A against unintended or spontaneous opening. This means that the motor hood 4 is fixed or held in the direction of an adjustment path 6 here.

[0049] FIG. 1B shows a partially open position of the engine hood 4, the rubber element 4 touching or being in contact with the tube 5. This position also corresponds in principle to FIG. 3BB. The closure position according to FIG. 1A also corresponds in principle to the closure positions which are shown in FIG. 3AA and FIG. 3BA.

[0050] In FIGS. 3AA-3BD, various positions or shapes of the closure 3 or the two closure elements 4, 5 are namely depicted diagrammatically in order to illustrate the invention. For instance, FIGS. 3AA-3AD show various positions during opening or the opening operation, and FIGS. 3BA-3BD show various positions during closing or the closing operation.

[0051] FIG. 3AD shows the two “maximum” positions of the tube 5 or second closure element 5 in relation to the first closure element 4 or rubber element 4, in part using dashed lines. It can thus be seen that a release path 8 is considerably longer or greater than a fixing path 9. Here, the release path 8 and the fixing path 9 extend firstly from the closure position (see shown in each case using dashed lines in FIGS. 3AD and 3BD and see FIGS. 3AA and 3BA in each case as far as a position, in which firstly the two closure elements 4, 5 touch or are in contact for the first time in the direction of the adjustment path during closing (cf. FIG. 3BD) or in which secondly the two closure elements 4, 5 last touch or are in contact (cf. FIG. 3AD).

[0052] For improved understanding of the movement sequences during opening and closing, arrows are additionally depicted which diagrammatically show the deformation or bends of the rubber element 4 or its lug 7. It can thus be seen that the lug 7 has a smaller cross section than in flank portion 11 of the rubber element 4, with the result that this portion 11 is deformed to a lesser extent both during opening and during closing/fixing than the lug 7. Precisely during opening, however, this portion 11 advantageously generates a restoring force or resistance which is to be overcome. Just like the paths of differing length, that is to say the release path 8 and the fixing path 9, this has a positive effect on the closure 3 in the context of the invention.

[0053] Considerably more energy thus has to be applied during opening according to FIG. 3AA-FIG. 3AD—than during closing according to FIG. 3BA—FIG. 3BD, which effectively prevents unintended opening during operation of the vibrator or the like and is therefore of great advantage. The opening force which is to be applied by the user can advantageously be set or limited, however, by way of the dimensioning of the rubber element 4 or the lug 7 and/or the portion 11. Thus, for example, a maximum opening force to be applied of approximately 200 N can be realized, which is pleasant for normal users.

[0054] The rubber element 4 is advantageously shaped in such a way that, during closing in the closure position according to FIG. 3BA, the lug 7 snaps out after bending in according to FIG. 3BB and, in addition, makes contact with the tube 5 at a second location 10, an advantageous prestress of the closure 3 being realized by way of the location 10. The prestressing force can thus be set by way of advantageous dimensioning of the lug 7 and the location 10.

[0055] FIG. 2 diagrammatically shows a structural unit 12, in which a so-called second closure element 5 (not shown in greater detail but as far as possible with a round cross section here) can be introduced centrally. The two lugs 7 and the two portions 11 of the structural unit 12 correspond to those of the variants according to FIGS. 1A or 1B or any of FIGS. 3AA-3BD, and are correspondingly deformed in principle during opening or closing/fixing. In addition, these portions 11 are fixed firmly on a base or metal element 13, with the result that the structural unit 12 which can be handled in one piece is realized in an advantageous way.

[0056] This structural unit 12 realizes double-sided or symmetrical force loading of the covering unit 1 (not shown in greater detail in FIG. 2). According to FIGS. 1A and 1B, the two closures 3 or closure elements 4 which are individual or spaced apart from one another and are arranged on both sides on an edge portion of the motor hood 1 advantageously make symmetrical or centering force loading possible.