Working machinery

Abstract

To provide a work machine that can reliably lock the rotational movement of the upper rotating body relative to the lower traveling body. [Solution] In a hydraulic excavator 1 comprising a traveling body 2, a slewing body 3, and a locking device 6 for locking the slewing motion of the slewing body 3 relative to the traveling body 2, the locking device 6 includes a connecting bracket 60 that connects the traveling body 2 and the slewing body 3, a first fixing bolt 61 that detachably fixes the connecting bracket 60 to the slewing body 3, and a second fixing bolt 62 that detachably fixes the connecting bracket 60 to the traveling body 2. The connecting bracket 60 is fixed to the traveling body 2 via the second traveling body side mounting bolt 240B by fastening the second fixing bolt 62 to a screw hole 246 formed in the head portion 242 of the second traveling body side mounting bolt 240B that attaches the traveling body side slewing wheel 24 to the round body 23 of the traveling body 2.

Description

Technical Field

[0001] The present invention relates to a working machine in which the upper part of the main body is rotatable with respect to the lower part.

Background Art

[0002] In a working machine capable of a turning operation such as a hydraulic excavator, generally, in order to prevent the upper revolving body, which is the upper part of the main body, from unexpectedly turning with respect to the lower traveling body, which is the lower part of the main body, during rest or transportation, a locking device that mechanically locks the upper revolving body to the lower traveling body is provided.

[0003] For example, Patent Document 1 discloses a locking device including a locking pin provided so as to be able to project from the upper revolving body side toward the lower traveling body side, and a locking plate fixed on the outer peripheral surface of a round cylinder on the lower traveling body and having a locking hole into which the locking pin is inserted.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the case of the locking device described in Patent Document 1, the mechanism locks the rotational movement of the upper slewing body relative to the lower traveling body by inserting a locking pin into a locking hole, resulting in play due to the gap between the locking pin and the locking hole. Situations where locking the rotational movement of the upper slewing body relative to the lower traveling body is required include not only when the machine is stationary or during transport, but also, for example, during maintenance work on the blast ladle. If the locking device described in Patent Document 1 is used during this work, the play between the locking pin and the locking hole may cause the work device attached to the upper slewing body to shake, potentially damaging the blast ladle. Furthermore, during work, the locking pin may come out of the locking hole, unintentionally releasing the lock on the rotational movement of the upper slewing body relative to the lower traveling body.

[0006] Therefore, the object of the present invention is to provide a work machine that can reliably lock the rotational movement of the upper rotating body relative to the lower traveling body. [Means for solving the problem]

[0007] To achieve the above objective, the present invention provides a work machine comprising: a traveling body which forms the lower part of the main body; a slewing body which is rotatably mounted above the traveling body via a pair of slewing wheels and forms the upper part of the main body; and a locking device for locking the slewing movement of the slewing body relative to the traveling body, wherein the locking device comprises: a connecting bracket which connects the traveling body and the slewing body; a first fixing bolt which detachably fixes the connecting bracket to the slewing body; and a second fixing bolt which detachably fixes the connecting bracket to the traveling body, wherein the connecting bracket is fixed to the traveling body via the mounting bolt by fastening the second fixing bolt to a screw hole formed in the head of a mounting bolt which attaches one of the slewing wheels to the round body of the traveling body. [Effects of the Invention]

[0008] According to the present invention, the rotational movement of the upper rotating body relative to the lower traveling body can be reliably locked. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments. [Brief explanation of the drawing]

[0009] [Figure 1] This is an external side view showing one example configuration of a hydraulic excavator according to an embodiment of the present invention. [Figure 2] This is a front view showing the framework of the running and rotating parts. [Figure 3] This is a side view showing the framework of the running and rotating parts. [Figure 4] Figure 3 shows a cross-sectional view along line IV-IV. [Figure 5] This is a perspective view showing a pair of slewing wheels and their surrounding areas. [Figure 6] This figure shows the top and side views of the mounting bolt on the first running body. [Figure 7] This figure shows the top and side views of the mounting bolt on the second travel body. [Figure 8] This is an enlarged side view showing a magnified view of the locking mechanism. [Modes for carrying out the invention]

[0010] Hereinafter, as one embodiment of the working machinery according to the present invention, a crawler-type hydraulic excavator used for maintenance work on a blast ladle will be described.

[0011] <Overall configuration of hydraulic excavator 1> First, the overall configuration of hydraulic excavator 1 will be explained with reference to Figures 1 to 5.

[0012] Figure 1 is an external side view showing an example configuration of a hydraulic excavator 1 according to an embodiment of the present invention. Figure 2 is a front view showing the framework of the traveling body 2 and the slewing body 3. Figure 3 is a side view showing the framework of the traveling body 2 and the slewing body 3. Figure 4 is a cross-sectional view taken along line IV-IV in Figure 3. Figure 5 is a perspective view showing a pair of slewing wheels 24, 35 and their surrounding areas.

[0013] As shown in Figure 1, the hydraulic excavator 1 comprises a traveling body 2 which forms the lower part of the main body, a rotating body 3 which is rotatably mounted above the traveling body 2 and forms the upper part of the main body, and a working device 4 attached to the front of the rotating body 3.

[0014] As shown in Figures 1-3, the vehicle 2 comprises a base vehicle frame 21, a pair of crawlers 22 attached to the left and right sides of the vehicle frame 21, and a cylindrical body 23 extending upward from the vehicle frame 21 (towards the side of the rotating body 3).

[0015] The vehicle 2 moves by rotating a pair of crawlers 22 in contact with the ground using the driving force of a pair of driving motors (not shown). The pair of driving motors are mounted on the left and right sides of the vehicle 2, corresponding to the left and right crawlers 22 respectively, and by driving them independently, the left and right crawlers 22 can be rotated independently in forward and reverse directions. Note that in Figure 1, only the left crawler 22 of the pair of left and right crawlers 22 is shown.

[0016] As shown in Figure 1, the slewing body 3 comprises a base slewing frame 31, an operator's cab 32 where the operator sits, a machine room 33 that houses the equipment necessary to drive the hydraulic excavator 1, and a counterweight 34 that maintains balance with the work device 4 to prevent the hydraulic excavator 1 from tilting. On the slewing frame 31, the operator's cab 32 is placed at the front, the counterweight 34 at the rear end, and the machine room 33 is placed between the operator's cab 32 and the counterweight 34.

[0017] As shown in FIGS. 2 and 3, the swivel body 3 swivels with respect to the traveling body 2 via a pair of swivel wheels 24 and 35. The pair of swivel wheels 24 and 35 are arranged side by side in the vertical direction (i.e., the height direction of the main body) with their radial directions being horizontal.

[0018] As shown in FIGS. 4 and 5, one swivel wheel 24 is attached to the upper outer peripheral surface of the round body 23 of the traveling body 2 by a plurality of mounting bolts 240 arranged at predetermined intervals in the circumferential direction. The other swivel wheel 35 is attached to the central portion on the lower surface side of the swivel frame 31 of the swivel body 3 by a plurality of mounting bolts 350 arranged at predetermined intervals in the circumferential direction.

[0019] Hereinafter, one swivel wheel 24 will be referred to as the "traveling body side swivel wheel 24", and the mounting bolts 240 attaching the traveling body side swivel wheel 24 to the round body 23 will be referred to as the "traveling body side mounting bolts 240". The other swivel wheel 35 will be referred to as the "swivel body side swivel wheel 35", and the mounting bolts 350 attaching the swivel body side swivel wheel 35 to the swivel frame 31 will be referred to as the "swivel body side mounting bolts 350".

[0020] As shown in FIG. 4, the traveling body side swivel wheel 24 and the swivel body side swivel wheel 35 are arranged concentrically with their centers coinciding with the swivel center C. As shown in FIGS. 4 and 5, the traveling body side swivel wheel 24 is formed with a diameter smaller than that of the swivel body side swivel wheel 35 and is arranged inside the swivel body side swivel wheel 35 when viewed in the vertical direction. In other words, the swivel body side swivel wheel 35 is formed with a diameter larger than that of the traveling body side swivel wheel 24 and is arranged outside the traveling body side swivel wheel 24 when viewed in the vertical direction.

[0021] The work device 4 is hydraulically driven and, in this embodiment, is specifically designed for maintenance work on the blast ladle. As shown in Figure 1, the work device 4 comprises a first arm 41 whose base end is rotatably attached to the slewing frame 31, a first arm cylinder 41A that drives the first arm 41, a second arm 42 rotatably attached to the tip of the first arm 41, a second arm cylinder 42A that drives the second arm 42, and a rod-shaped work tool 43 attached to the upper surface of the second arm 42.

[0022] The first arm cylinder 41A connects the slewing frame 31 and the first arm 41, and the extension and retraction of the rod causes the first arm 41 to rotate (elevate) in the height direction relative to the slewing body 3. The second arm cylinder 42A connects the first arm 41 and the second arm 42, and the extension and retraction of the rod causes the second arm 42 to rotate (elevate) in the height direction relative to the first arm 41.

[0023] The work tool 43 is driven by a hydraulic motor and operates along the extension direction of the second arm 42. For example, when inspecting and repairing the bottom (back side) of a blast ladle, the hydraulic excavator 1 works with the work tool 43 protruding a predetermined upper limit length from the tip of the second arm 42. Also, for example, when removing iron or other materials attached to the edge of the entrance of a blast ladle, the hydraulic excavator 1 works with the work tool 43 protruding a predetermined length from the tip of the second arm 42, by rotating the first arm 41 and the second arm 42 in the height direction or swinging them left and right relative to the slewing body 3.

[0024] When performing maintenance work on the blast ladle, it is necessary to keep the slewing body 3 from rotating relative to the traveling body 2 on the hydraulic excavator 1, and the locking device 6 locks the slewing movement of the slewing body 3 relative to the traveling body 2.

[0025] <Configuration of locking device 6> Next, the configuration of the locking device 6 will be explained with reference to Figures 4 and 5, as well as Figures 6 to 8.

[0026] Figure 6 shows the top and side views of the first travel body side mounting bolt 240A. Figure 7 shows the top and side views of the second travel body side mounting bolt 240B. Figure 8 is an enlarged side view showing the configuration of the locking device 6.

[0027] As shown in Figures 4, 5, and 8, the locking device 6 includes a connecting bracket 60 that connects the traveling body 2 and the slewing body 3, a first fixing bolt 61 that detachably fixes the connecting bracket 60 to the slewing body 3, and a second fixing bolt 62 that detachably fixes the connecting bracket 60 to the traveling body 2.

[0028] The connecting bracket 60 includes a first plate portion 601 which is the fixed part that is fixed to the swivel body 3, and a second plate portion 602 which is the fixed part that is fixed to the traveling body 2. In this embodiment, as shown in Figure 8, the connecting bracket 60 is made by bending a metal plate member, and the first plate portion 601 and the second plate portion 602 extend in directions perpendicular to each other.

[0029] The first plate portion 601 is fixed to a seat 310 that extends downward (towards the traveling body 2) from the outer region of the slewing wheel 35 on the lower surface of the slewing frame 31 via a first fixing bolt 61 and a first washer 61A. In this embodiment, the thickness direction of the seat 310 is aligned with the radial direction of the slewing wheel 35 on the slewing wheel, and the outer surface of the first plate portion 601 is the surface opposite to the outer circumferential surface of the pair of slewing wheels 24 and 35.

[0030] Therefore, the fixing direction of the first fixing bolt 61 is from the radially outer side of the slewing wheel 35 on the slewing body side toward the pivot center. In this way, the first fixing bolt 61 can be fastened to the seat 310 from the radially outer side of the slewing wheel 35 on the slewing body side toward the pivot center, making it easier for the worker to reach in and fix the connecting bracket 60 to the slewing body 3.

[0031] The second plate portion 602 is fixed to the vehicle-side mounting bolt 240, to which the vehicle-side slewing wheel 24 is attached, via a second fixing bolt 62 and a second washer 62A. As shown in Figures 6 and 7, the vehicle-side mounting bolt 240 consists of a first vehicle-side mounting bolt 240A and a second vehicle-side mounting bolt 240B, which have different structures, and the second plate portion 602 is fixed to the second vehicle-side mounting bolt 240B.

[0032] As shown in Figure 6, the first running body side mounting bolt 240A has a head portion 241 with a hexagonal outer shape and an axial shaft portion 243 extending from the head portion 241. Similarly, as shown in Figure 7, the second running body side mounting bolt 240B has a head portion 242 with a hexagonal outer shape and an axial shaft portion 244 extending from the head portion 242.

[0033] However, the structure of the head portion 242 of the second running body side mounting bolt 240B differs from the structure of the head portion 241 of the first running body side mounting bolt 240A. Specifically, as shown in Figure 7, the thickness H2 of the head portion 242 is thicker than the thickness H1 of the head portion 241 of the first running body side mounting bolt 240A (H2 > H1), and a screw hole 246 (shown as a dashed line in the right side view of Figure 7) into which the second fixing bolt 62 is inserted is formed in the center.

[0034] In this embodiment, the multiple vehicle-side mounting bolts 240 included a first vehicle-side mounting bolt 240A and a second vehicle-side mounting bolt 240B, but this is not limited to this, and all of the multiple vehicle-side mounting bolts 240 may be second vehicle-side mounting bolts 240B to which the second fixing bolt 62 is fastened.

[0035] The second plate portion 602 is fixed to the traveling body side slewing wheel 24 (traveling body 2) via the second traveling body side mounting bolt 240B when the second fixing bolt 62 is fastened into the screw hole 246 while the second fixing bolt 62 is in contact with the upper surface of the head portion 242 of the second traveling body side mounting bolt 240B (the surface to be fixed of the second plate portion 602).

[0036] Therefore, the fixing direction of the second fixing bolt 62 is from the lower side to the upper side in the height direction of the traveling body 2. In this way, the second fixing bolt 62 can be fastened to the traveling body side slewing wheel 24 (second traveling body side mounting bolt 240B) from the lower side to the upper side in the height direction of the traveling body 2, making it easier for the worker to reach in and fix the connecting bracket 60 to the traveling body 2.

[0037] In this embodiment, the first fixing bolt 61 and the second fixing bolt 62 have their fixing directions perpendicular to each other. As a result, the connecting bracket 60 can have a simple structure, consisting only of a metal plate member bent in the central region in the longitudinal direction, and can be manufactured without much effort or cost. Note that the fixing directions of the first fixing bolt 61 and the fixing directions of the second fixing bolt 62 do not necessarily have to be perpendicular; they only need to intersect.

[0038] Furthermore, as shown in Figure 5, the first plate portion 601 has a first fixing bolt hole 601A through which the first fixing bolt 61 is inserted. In this embodiment, the connecting bracket 60 is fixed to the swivel body 3 by a pair of first fixing bolts 61. For this reason, the first plate portion 601 has a pair of first fixing bolt holes 601A arranged in the width direction (corresponding to the short side direction of the plate member for forming the connecting bracket 60) at a predetermined interval.

[0039] Furthermore, in this embodiment, each of the pair of first fixing bolt holes 601A is formed as an elongated slot extending toward the end on the second plate portion 602 side. That is, when the connecting bracket 60 is fixed to the seat 310 (swivel body 3), each of the pair of first fixing bolt holes 601A becomes an elongated slot extending in the height direction of the swivel body 3.

[0040] Here, the fixing position of the connecting bracket 60 to the slewing body 3 in the height direction depends on the thickness H2 of the head portion 242 of the second travel body side mounting bolt 240B. Therefore, by forming the first fixing bolt hole 601A as an elongated hole extending in the height direction of the slewing body 3, and by setting the fixing direction of the first fixing bolt 61 to a direction from the radially outer side of the slewing wheel 35 on the slewing body side toward the pivot center, the degree of freedom regarding the fixing position of the connecting bracket 60 to the slewing body 3 in the height direction is increased.

[0041] Therefore, even if the thickness H2 of the head portion 242 of the second travel body side mounting bolt 240B is changed, the connecting bracket 60 can be fixed to the slewing body 3 without using adjustment parts such as shims. In other words, the second travel body side mounting bolt 240B does not require a special bolt to fix the connecting bracket 60, and a general-purpose bolt can be used.

[0042] Similarly, as shown in Figure 4, the second plate portion 602 has a second fixing bolt hole 602A through which the second fixing bolt 62 is inserted. In this embodiment, the connecting bracket 60 is fixed to the traveling body 2 by a pair of second fixing bolts 62. For this reason, the second plate portion 602 has a pair of second fixing bolt holes 602A arranged in the width direction (corresponding to the short side direction of the plate member for forming the connecting bracket 60) at a predetermined interval.

[0043] Furthermore, in this embodiment, each of the pair of second fixing bolt holes 602A is formed as an elongated slot extending toward the end on the first plate portion 601 side. That is, when the connecting bracket 60 is fixed to the second travel body side mounting bolt 240B (travel body 2), each of the pair of second fixing bolt holes 602A becomes an elongated slot extending along the radial direction of the travel body side slewing wheel 24.

[0044] Here, the fixing position of the connecting bracket 60 on the traveling body 2 depends on the diameter of the traveling body's slewing wheel 24. Therefore, by forming the second fixing bolt hole 602A as an elongated hole extending in the radial direction of the traveling body's slewing wheel 24, and by setting the fixing direction of the second fixing bolt 62 to be from the lower side to the upper side in the height direction of the traveling body 2, the connecting bracket 60 can be fixed to traveling body's slewing wheel 24 of various diameters. In other words, there is no need to prepare a dedicated locking device 6 for each model of hydraulic excavator 1.

[0045] As shown in Figure 4, multiple locking devices 6 are arranged in a row along the circumferential direction of the pair of slewing wheels 24 and 35. In this embodiment, seven locking devices 6 are arranged in a row along the circumferential direction of the pair of slewing wheels 24 and 35.

[0046] Specifically, in the longitudinal direction of the slewing body 3, four of the seven locking devices 6 are positioned in front of the pivot center C, and three of the seven locking devices 6 are positioned behind the pivot center C. Furthermore, of the four locking devices 6 positioned in front of the pivot center C, two are positioned to the left of the pivot center C, and the remaining two are positioned to the right of the pivot center C.

[0047] This is because the outer area of ​​the slewing wheel 35 on the lower surface of the slewing frame 31 is limited. In the slewing frame 31, the outer area of ​​the slewing wheel 35 does not exist in the central part including the slewing center C. Also, in the slewing frame 31, the working device 4 is attached to the central part in front of the slewing center C, so the outer area of ​​the slewing wheel 35 does not exist in this part either. In this embodiment, the locking device 6 can be fixed using the limited free space in the slewing frame 31, so there is no need to modify the slewing frame 31 to fix the locking device 6, and thus it is possible to reduce labor and costs.

[0048] As described above, in the hydraulic excavator 1, the slewing body 3 is securely fixed to the traveling body 2 by the first fixing bolt 61 and the second fixing bolt 62, so that the slewing motion of the slewing body 3 relative to the traveling body 2 can be reliably locked. This prevents situations such as the slewing body 3 rattling during maintenance work on the molten ladle, causing the work device 4 to unexpectedly shake and damage the molten ladle, or the lock coming undone.

[0049] Furthermore, since the locking device 6 is composed of a connecting bracket 60, a first fixing bolt 61, and a second fixing bolt 62, it does not need to be welded to the main structural components of the hydraulic excavator 1, such as the cylindrical body 23. If a large addition were welded to the main structural components, high stress would be generated at the welded points, causing damage. Therefore, by using the locking device 6 to lock the rotational movement of the slewing body 3 relative to the traveling body 2, the quality of the hydraulic excavator 1 can be maintained, and the effort and cost of modifications can be reduced.

[0050] Embodiments of the present invention have been described above. It should be noted that the present invention is not limited to the embodiments described above, and various modifications are included. For example, the embodiments described above are described in detail to make the present invention easier to understand, and are not necessarily limited to those having all the described configurations. Furthermore, it is possible to replace some of the configurations of this embodiment with those of other embodiments, and it is also possible to add configurations from other embodiments to the configuration of this embodiment. Moreover, it is possible to add, delete, or replace some of the configurations of this embodiment with those of other embodiments.

[0051] For example, in the above embodiment, a crawler-type hydraulic excavator 1 equipped with a special working device 4 used for maintenance work on a blast ladle was described as one form of work machine, but it is not limited to this, and other work machines such as a hydraulic excavator equipped with a normal bucket may also be used. However, in view of the operation and effects of the present invention, it is more desirable that it be applied to a hydraulic excavator 1 used for maintenance work on a blast ladle.

[0052] In the above embodiment, the locking device 6 was used to describe the situation in which the rotational movement of the rotating body 3 is locked, using maintenance work on the blast ladle as an example. However, it is not limited to this, and may also occur when the hydraulic excavator 1 is idle or during transport. [Explanation of symbols]

[0053] 1: Hydraulic excavator (working machine) 2: Running body 3: Rotating body 6: Locking device 23: Round body 24: Side slewing wheel of the vehicle (one of the slewing wheels) 35: Side slewing wheel of the slewing body (the other slewing wheel) 60: Connecting bracket 61: First fixing bolt 62: Second fixing bolt 240B: Mounting bolt for the second running body (mounting bolt) 242: Head section 246: Screw hole 601A: First fixing bolt hole 602A: Second fixing bolt hole C: Center of rotation

Claims

1. The lower part of the main body is the running body, A slewing body is provided above the traveling body via a pair of slewing wheels so as to be rotatable and forms the upper part of the main body, A locking device for locking the rotational movement of the rotating body relative to the traveling body, In the work machine, The locking device is A connecting bracket that connects the traveling body and the rotating body, A first fixing bolt that removably secures the connecting bracket to the swivel body, A second fixing bolt for detachably fixing the connecting bracket to the traveling body, It has, The aforementioned connecting bracket is The second fixing bolt is fastened to the rotating wheel on the round body of the traveling body through the mounting bolt by fastening it into a threaded hole formed in the head of the mounting bolt that attaches one of the rotating wheels to the round body of the traveling body. A work machine characterized by the following features.

2. In the work machine described in claim 1, The locking device is Multiple units are arranged in the front-rear direction of the pivoting body, both in front of and behind the pivoting center. A work machine characterized by the following features.

3. In the work machine described in claim 1, The first fixing bolt and the second fixing bolt have their fixing directions intersecting. A work machine characterized by the following features.

4. In the work machine described in claim 3, The fixing direction of the first fixing bolt is from the radially outer side of the other slewing ring attached to the slewing body toward the center of rotation, The fixing direction of the second fixing bolt is from the lower side to the upper side in the height direction of the traveling body. A work machine characterized by the following features.

5. In the work machine described in claim 4, The aforementioned connecting bracket includes: The first fixing bolt hole through which the first fixing bolt is inserted is formed as an elongated hole extending in the height direction of the swivel body when the connecting bracket is fixed to the swivel body. A work machine characterized by the following features.

6. In the work machine described in claim 4, The aforementioned connecting bracket includes: The second fixing bolt hole through which the second fixing bolt is inserted is formed as an elongated hole extending radially in the direction of the slewing wheel when the connecting bracket is fixed to the traveling body. A work machine characterized by the following features.

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