JP5116713B2 - Step device for lifting and lowering construction machinery - Google Patents

Description

  The present invention relates to a step device that is attached to a side frame of a lower traveling body of a construction machine such as a hydraulic excavator, and that allows an operator, a maintenance inspector, and the like to ascend and descend to a vehicle body, a driver's cab, and the like.

  In general, a construction machine such as a hydraulic excavator has an upper swing body installed on a lower traveling body via a swing device, and a driver's cab and a power unit are mounted on the upper swing body, and a work front is mounted on the upper swing body. It is configured by mounting. In this type of construction machine, because the operator goes up and down to the operator's cab, and the maintenance and inspection workers go up and down on the upper swinging body, a step device for lifting is attached to the outer surface of the side frame of the lower traveling body. ing.

  Japanese Patent Application Laid-Open No. H11-228707 discloses a lifting and lowering step device of this type that is shown in FIGS. 11 and 12 in order to prevent damage to steps and bolts caused by rocks or the like from below. This lifting and lowering step device is provided with tapered wall portions 41 extending downward from the lower end of the footrest portion 40 toward the side frame 14 side, and provided with attachment portions 42 at both ends of the footrest portion 40. It is attached to the side frame 14 with bolts 43.

JP 2006-88723 A

  In the conventional lifting and lowering step device for a construction machine, even if rock 44 or the like that jumps up and scatters from below the front of the step during work collides with the taper wall 41, the shock is absorbed by the taper wall 41. Since the impact applied to the step and the bolt 43 is relieved, damage to the step and the bolt 43 can be prevented. However, as shown by the arrow 26 in FIG. 11, if the footrest 40 or the taper wall 41 receives the rock flying from the side of the step, the step or the bolt 43 may be damaged or broken. There was a problem.

  In view of the above problems, an object of the present invention is to provide a step device for raising and lowering a construction machine that is not easily damaged by not only rocks flying from the front of the step but also rocks flying from the side of the step. To do.

The step device for raising and lowering the construction machine according to claim 1 is the step device for raising and lowering attached to the side frame constituting the lower traveling body of the construction machine.
The step has a center plate portion, side plate portions on both the left and right sides, and an upper plate portion ,
The central plate portion is inclined so as to gradually approach the side frame side from the upper footrest portion spaced from the side frame to the lower end,
The side plate portion is provided in a range extending from the left and right sides of the central plate portion to the side frame, and the distance between the upper ends of the side plate portions gradually increases as the distance from the side frame increases. And tilt as
The upper plate portion is welded to at least both side plate portions of the center plate portion and the both side plate portions,
The upper plate portion is also welded to the side frame, and the side portion of the side plate portion and the lower portion of the central plate portion are also welded to the side frame .

According to the present invention , even if rocks or the like flying from below the front of the step collide with the center plate portion or the side plate portion, the impact is mitigated because they have an inclined structure. In addition, even if rocks flying from the side of the step collide with the side plate, they have a structure that is inclined obliquely downward, so that the impact can be mitigated in the same way as rocks flying from the lower side. it can. Therefore, the impact applied to the step is relieved regardless of the direction of the rocks flying during the work, and damage such as deformation of the step can be prevented.

In addition, since the upper plate portion welded to at least the both side plate portions of the center plate portion and the both side plate portions is provided, the step device can be provided, and the step device can be provided which is less likely to be deformed.

Furthermore, with also welded to the upper plate portion to the side frame, since the sides and bottom of the central plate portion of the side plate portion is welded to the side frame, box structure is achieved, further increases the strength of the step Thus, it is possible to provide a step device that is less prone to deformation and the like.

It is a side view of the construction machine which shows the example of application of the raising / lowering step apparatus of this invention. It is a top view which shows the reference example of the step apparatus for raising / lowering of this invention. It is a front view of the raising / lowering step apparatus of this reference example . It is EE sectional drawing of FIG. It is a top view which shows one Embodiment of the step apparatus for raising / lowering of this invention. It is a front view of the step apparatus for raising / lowering of embodiment of FIG. It is FF sectional drawing of FIG. It is a top view which shows the other reference example of the raising / lowering step apparatus of this invention. It is a front view which shows the raising / lowering step apparatus of the reference example of FIG. FIG. 10 is an enlarged GG sectional view of FIG. 9. It is a front view which shows the conventional raising / lowering step apparatus. It is a side view which shows the conventional raising / lowering step apparatus.

  FIG. 1 is a side view showing an example of a construction machine to which the present invention is applied. In this example, the construction machine is a hydraulic excavator. In this hydraulic excavator, an upper swing body 3 is installed on a lower traveling body 1 via a swing device 2, and a power unit 4, a cab 5 and the like are mounted on the upper swing body 3, and a work front 6 having an articulated structure. Is attached. The work front 6 includes a boom 8 that can be mounted on the upper swing body 3 by a boom cylinder 7, an arm 10 that can be pivoted by an arm cylinder 9 at the tip of the boom 8, and a bucket cylinder at the tip of the arm 10. 11 and a bucket 12 that is rotatably attached to the vehicle.

  The lower traveling body 1 is provided with a driving wheel 15 at the rear part of the left and right side frames 14 and a front driven wheel 16 between which a crawler belt 18 is attached by being supported by a roller 17 attached to the side frame 14. A step 20 is provided on the outer surface of the side frame 14 so that an operator, a maintenance inspector, and the like can move up and down to the upper swing body 3 and the cab 5 as the vehicle body.

2 to 4 show reference examples of the step device of the present invention. The step 20 includes a center plate portion 21 having a footrest portion 21a formed by an uneven portion on an upper portion, and a side plate portion 22 formed integrally with the center plate portion 21 by bending or welding to the left and right of the center plate portion 21. Have The central plate portion 21 is inclined so as to gradually approach the side frame 14 side from the upper footrest portion 21a spaced from the side frame 14 to the lower end.

  Further, as shown in FIG. 2, the side plate portion 22 is provided in a range extending from the left and right sides of the central plate portion 21 to the side frame 14, and as shown in FIG. As the distance from each other increases, the width gradually increases (W1> W2). The lower end portion of the central plate portion 21 is fixed to the outer surface of the side frame 14 by welding. 4 denotes a welded portion of the central plate portion 21 to the side frame 14. Further, the side portion of the side plate portion 22 is also welded to the outer surface of the side frame 14. 2 denotes a welded portion of the side plate portion 22 to the side frame 14.

  As shown in FIG. 2, in a plan view, the inclination angle θ1 of the side plate portion 22 with respect to the side frame 14 and the central plate portion 21 is preferably 30 to 60 degrees in order to reduce the impact of the flying rock. It may be other than this angle. In addition, as shown in FIG. 3, in front view, the inclination angle θ2 with respect to the horizontal line of the side portion 22a is preferably 30 to 60 degrees in order to reduce the impact of the flying rock, but other than this angle. May be.

In this reference example , since the central plate portion 21 and the side plate portion 22 are inclined so that the lower portions thereof are close to the side frame 14, as shown by the arrow 25 in FIG. Even if it collides with the part 21 or the side plate part 22, since these have the inclined structure, the impact is alleviated. Further, even if rocks or the like flying from the side of step 20 collide with the side plate portion 22 as shown by an arrow 26 in FIG. 3, since these have a structure inclined obliquely downward, the shock can be similarly mitigated. Can do. Therefore, the impact applied to step 20 is alleviated regardless of the direction of the rocks that fly during the work, and damage such as deformation of step 20 can be prevented.

5-7 shows an embodiment of step device of the present invention. In this embodiment, an upper plate portion 27 welded to the central plate portion 21 and both side plate portions 22 is further provided between the upper portion of the central plate portion 21 and the side frame 14. In FIG. 7, reference numerals 28 and 30 denote welds to the central plate portion 21 and the side plate portion 22 of the upper plate portion 27, respectively.

In this way, by providing the upper plate portion 27 welded to the central plate portion 21 and the side plate portion 22 between the central plate portion 21 and the side frame 14, the step strength is increased, and further, deformation and the like are unlikely to occur. An apparatus can be provided. In addition, even if the upper board part 27 is the structure welded to at least one of the center board part 21 and the side board part 22, intensity | strength can be raised rather than the thing of the reference example of FIGS.

  Further, as shown in FIGS. 5 and 7, the upper plate portion 27 is used to close the space between the upper portions of the side plate portion 22 and the upper plate portion 21 and the side frame 14. By further welding the portion 27 to the side frame 14 and further welding the upper plate portion 27 to the side plate portion 22 (30 indicates a welded portion), as shown in FIG. It is possible to provide a step that is less prone to deformation and the like.

8 to 10 show other reference examples of the step device of the present invention, in which the step body 33 is attached to the side frame 14 with bolts 32. FIG. 8-10, the same code | symbol as FIGS. 5-7 shows the same component and component. That is, the step body 33 has the inclined center plate portion 21 and side plate portion 22 as described above. The step body 33 further includes a vertical plate 34 and a mounting plate 35. The vertical plate 34 is attached by welding to the lower surface of the upper plate portion 27 and the back surface of the central plate portion 21. The mounting plate 35 is attached by welding its upper side to the lower surface of the upper plate portion 27, welding its side to the vertical plate 34, and welding its lower side to the back surface of the central plate portion 21. Reference numeral 36 denotes a mounting seat welded to the side frame 14. The central plate 21 is provided with an opening 21b for inserting and removing the mounting bolt 32 and turning the bolt 32.

In this reference example , as shown in FIG. 10, the step body 33 is attached by inserting a bolt 37 from the opening 21 b of the central plate portion 21 and inserting it into a bolt insertion hole 35 a provided in the attachment plate 35. This is performed by screwing into a screw hole 36a provided in the screw hole 36a. As described above, by adopting a structure in which the step body 33 is detachably attached to the side frame 14 with the bolts 32, the step body 33 can be easily replaced when the step body 33 is damaged.

In the above-described embodiment shown in FIGS . 5 to 7 , the upper plate portion 27 is constituted by a flat plate. However, as the upper plate portion 27, a plate or a lattice having an uneven surface on the upper surface for preventing slippage. A shaped plate may be used. Further, an uneven plate or a lattice plate may be provided on the upper plate portion 27 to prevent slipping.

1: lower traveling body, 2: swiveling device, 3: upper revolving body, 4: power unit, 5: cab, 6: front for work, 7: boom cylinder, 8: boom, 9: arm cylinder, 10: arm, 11: Bucket cylinder, 12: Bucket, 14: Side frame, 15: Drive wheel, 16: Driven wheel, 17: Roller, 18: Crawler belt, 20: Step, 21: Center plate part, 21a: Footrest part, 21b: Opening portion, 22: side plate portion, 23, 24: welded portion, 27: upper plate portion, 28-30: welded portion, 32: bolt, 33: step body, 34: vertical plate, 35: mounting plate, 35a: bolt Insertion hole, 36: mounting seat, 36a: screw hole

Claims (1)

In the step device for raising and lowering attached to the side frame constituting the lower traveling body of the construction machine,
The step has a center plate portion, side plate portions on both the left and right sides, and an upper plate portion ,
The central plate portion is inclined so as to gradually approach the side frame side from the upper footrest portion spaced from the side frame to the lower end,
The side plate portion is provided in a range extending from the left and right sides of the central plate portion to the side frame, and the distance between the upper ends of the side plate portions gradually increases as the distance from the side frame increases. And tilt as
The upper plate portion is welded to at least both side plate portions of the center plate portion and the both side plate portions,
A step device for raising and lowering a construction machine, wherein the upper plate portion is also welded to the side frame, and the side portion of the side plate portion and the lower portion of the central plate portion are also welded to the side frame .

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