Construction Machinery

Abstract

To improve workability in attaching / detaching a counterweight in a configuration where a counterweight comprising a first counterweight and a second counterweight is attached to a machine body.SOLUTION: A counterweight 9 comprises a first counterweight 90 and a second counterweight 190. The first counterweight 90 is directly fixed to an attachment portion 71 by a fixing bolt 213, to be mounted on an upper structure 20B. The second counterweight 190 makes an attaching member 200 engaged with a fitting hole 98 of the first counterweight 90 and is indirectly fixed to the attachment portion 71 via the first counterweight 90 by a connection bolt 215, to be mounted on the upper structure 20B.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a construction machine equipped with a work implement, and more particularly to a construction machine equipped with a counterweight that balances the weight of the front work implement. [Background technology]

[0002] Conventionally, a construction machine includes a lower traveling body, an upper rotating body that is rotatably provided above the lower traveling body, and a working machine that is supported on the front part of the upper rotating body so as to be rotatable up and down. The upper rotating body includes a rotating frame that forms a support structure, and a support bracket that supports the working machine is disposed at the front end of the rotating frame, and a counterweight that balances the weight of the working machine is disposed at the rear end.

[0003] The working machine has a boom connected to a support bracket, an arm connected to the end of the boom, and a working tool attached to the end of the arm. In the case of an excavator for excavation work, a working tool called a bucket is attached to the end of the arm. This working tool can be changed as appropriate depending on the purpose of the work; for example, when demolishing a reinforced concrete building, a working tool such as a steel frame cutting tool or a concrete crushing tool is attached to the end of the arm. The counterweight disposed at the rear end of the rotating frame is composed of a standard weight and an additional weight that can be attached and detached from the standard weight in order to accommodate fluctuations in the weight of the working machine due to changes in the working tool (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-007235 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the construction machine disclosed in Patent Document 1, the standard weight is provided with a standard weight bolt insertion hole through which the standard weight bolt is inserted and an additional weight bolt fastening hole for fastening the additional weight bolt, and the additional weight is provided with an additional weight bolt insertion hole through which the additional weight bolt is inserted and a standard weight bolt insertion / removal hole for inserting and removing the standard weight bolt. When attaching the additional weight to the back surface of the standard weight, the additional weight is brought into contact with the back surface of the standard weight so that the position of the additional weight bolt insertion hole of the additional weight matches the position of the additional weight bolt insertion hole of the standard weight, and the additional weight bolt is inserted into the additional weight insertion hole of the additional weight and screwed into the additional weight bolt fastening hole of the standard weight.

[0006] When a worker performs such work, he or she must align the additional weight bolt fastening hole of the standard weight with the additional weight bolt insertion hole of the additional weight and then insert the additional weight bolt. However, there is a problem that it takes time to align the additional weight bolt fastening hole of the standard weight with the additional weight bolt insertion hole of the additional weight. In addition, when removing the additional weight, there is a possibility that the bolt may break due to the weight of the additional weight while removing the additional weight bolt.

[0007] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a construction machine in which a counterweight comprising a first counterweight and a second counterweight is attached to a machine body, and which improves the ease of attaching and detaching the counterweight. [Means for solving the problem]

[0008] The construction machine of the present invention is a construction machine comprising a lower running body, an upper rotating body supported on the lower running body so as to be freely rotatable, and a work machine supported in front of the upper rotating body so as to be freely rotatable, wherein the upper rotating body comprises a first counterweight fixed by a screw fastener to a mounting portion erected at the rear of a rotating frame that rotates relative to the lower running body, and a second counterweight fixed to the first counterweight by a screw fastener, the first counterweight having a hanging hole on its upper portion, and the second counterweight having a hanging portion that hangs on the hanging hole.

[0009] A construction machine according to another aspect of the present invention is characterized in that a first notch is formed in the upper end surface of the first counterweight, the first notch being concave from the upper end surface downward, and the hanging hole is provided in the first notch, and a second notch is formed in the upper end surface of the second counterweight, the second notch being concave from the upper end surface downward, and the hanging portion is provided in the second notch.

[0010] A construction machine according to another aspect of the present invention is characterized in that the hanging portion comprises an attachment member that is L-shaped in side view, one end of the attachment member is connected to the second counterweight, and the other end of the attachment member is inserted into the hanging hole.

[0011] A construction machine according to another aspect of the present invention is characterized in that the first counterweight is provided with an insertion hole into which a screw fastener that fixes the first counterweight to the mounting portion is inserted, and the second counterweight is provided with a communication hole that communicates with the insertion hole.

[0012] A construction machine according to another aspect of the present invention is characterized in that the hanging portion is detachably fixed to the second counterweight.

[0013] A construction machine according to another aspect of the present invention is the construction machine according to any one of claims 1 to 5, characterized in that the hanging portion has a metal fitting mounting portion for mounting a lifting metal fitting. Effect of the Invention

[0014] According to the present invention, in a configuration in which a counterweight having a first counterweight and a second counterweight is attached to a machine body, the workability of attaching and detaching the counterweight can be improved. [Brief description of the drawings]

[0015] [Figure 1] 1 is a left side view of an excavation machine according to an embodiment of the present invention. FIG. [Diagram 2] 1 is a perspective view of an excavation machine according to an embodiment of the present invention, seen from the left rear. [Diagram 3] FIG. 2 is a plan view illustrating a configuration of a lower running body according to an embodiment of the present invention. [Figure 4] FIG. 2 is a front view of a first counterweight in the counterweight according to one embodiment of the present invention. [Diagram 5] FIG. 2 is a front view of a second counterweight in the counterweight according to one embodiment of the present invention. [Figure 6] FIG. 2 is a left side view, partially in section, of a state in which a first counterweight and a second counterweight are assembled according to one embodiment of the present invention. [Figure 7] FIG. 2 is a left rear perspective view showing an example of a mounting manner of the counterweight according to one embodiment of the present invention. [Figure 8] FIG. 2 is a left rear perspective view showing an example of a mounting manner of the counterweight according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention provides a counterweight configuration for balancing the weight of a work implement in a construction machine, which includes a first counterweight and a second counterweight, and aims to improve the ease of attaching and detaching the counterweight to and from the machine body by devising an attachment structure for the second counterweight to the first counterweight. Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] In this embodiment, an excavation machine, which is a slewing work vehicle, will be described as an example of the construction machine according to the present invention. However, the construction machine according to the present invention is not limited to excavation machines, and can be widely applied to other construction machines such as crane machines.

[0018] First, the overall configuration of an excavation work machine 1 according to this embodiment will be described with reference to Figures 1 and 3. As shown in Figures 1 and 2, the excavation work machine 1 has an excavation device 3 and an earth removal device 4 as work machines attached to a self-propelled traveling vehicle body.

[0019] In this excavation work machine 1, the lower traveling body 20A includes a pair of left and right crawler-type traveling parts 5, 5 and a machine body frame 6 as a base interposed between the left and right traveling parts 5, 5, and the upper rotating body 20B includes a revolving frame 7 mounted rotatably on the lower traveling body 20A and a driving part 50 provided on the revolving frame 7. The revolving frame 7 can revolve in either the left or right direction around an axis in the vertical direction relative to the machine body frame 6. A revolving bearing 8 (see FIG. 3) having a circular shape in a plan view is disposed on the upper surface of the machine body frame 6, and the bottom surface of the revolving frame 7 is connected onto the revolving bearing 8. The upper rotating body 20B revolves relative to the lower traveling body 20A by connecting the machine body frame 6 and the revolving frame 7 via the revolving bearing 8. The center of the circle of the revolving bearing 8 is the center of rotation of the upper rotating body 20B relative to the lower traveling body 20A.

[0020] The traveling unit 5 has a configuration in which a crawler belt is wound around a sprocket, an idler, and a plurality of rollers supported by the machine frame 6. The traveling unit 5 has a drive sprocket 5a, which is a drive wheel, at its rear end.

[0021] The soil removal device 4 is attached to the front side of the machine frame 6. The soil removal device 4 includes a support frame 40 and a blade 41, which is a blade supported by the support frame 40. The soil removal device 4 including these components is configured to be substantially symmetrical overall.

[0022] The support frame 40 is supported on the lower running body 20A so as to be vertically rotatable, and includes left and right arms 43 extending in the front-rear direction between the left and right running parts 5, 5, and a support cylinder part 42 installed between the left and right arms 43. The left and right arms 43 are attached to the machine body frame 6 so as to be vertically rotatable, with their base ends supported by support brackets 6b (see FIG. 3) provided on the front of the machine body frame 6 with the left-right direction as the rotation axis direction.

[0023] A blade cylinder 44 is disposed in the left-right center between the left and right arms 43 of the support frame 40 (see FIG. 3). The blade cylinder 44 is installed between the machine frame 6 and the support tube portion 42 with the cylinder's extension direction (longitudinal direction) aligned with the front-rear direction. The front end of the blade cylinder 44 is connected to the support tube portion 42 via a link member that is rotatable with the left-right direction as the rotation axis direction. The rear end of the blade cylinder 44 is supported by a support bracket 6a provided at the front of the machine frame 6 so as to be rotatable with the left-right direction as the rotation axis direction.

[0024] Therefore, the pair of left and right arms 43 swing the support bracket 6b about the rotation shaft as a fulcrum by the operation of the blade cylinder 44 provided in the left and right central portion between the machine frame 6 and the support frame 40. In other words, the blade 41 moves up and down via the support frame 40 as the blade cylinder 44 expands and contracts.

[0025] The excavation device 3 is a front working machine provided at the front of the upper rotating body 20B. A support bracket 7a for supporting the excavation device 3 is provided protruding forward from the left-right center of the front end of the rotating frame 7. A boom support bracket 31 forming the base end of the excavation device 3 is supported by the support bracket 7a so as to be rotatable with the vertical direction as the rotation axis direction.

[0026] The excavation device 3 has a boom 32 that constitutes its base side portion, an arm 33 connected to the tip side of the boom 32, and a bucket 34 attached to the tip of the arm 33. The excavation device 3 is arranged to swing left and right relative to the revolving frame 7 by a swing cylinder (not shown) arranged on the right side of its base end portion.

[0027] The excavation device 3 has a boom cylinder 35 that rotates the boom 32, an arm cylinder 36 that rotates the arm 33, and a bucket cylinder 37 that rotates the bucket 34. In the excavation device 3, the bucket 34 is detachably attached as a work attachment, and other attachments such as a clamping machine (fork) or a crusher (breaker) are attached in place of the bucket 34 depending on the work content.

[0028] A counterweight 9 for balancing the excavation device 3 is provided at the rear end of the upper rotating body 20B. The counterweight 9 includes a plate-shaped first counterweight 90 and a second counterweight 190 (see Figs. 4 and 5 described later). Depending on the weight of the attachment mounted on the tip of the arm 33 of the excavation device 3, only the first counterweight 90 or both the first counterweight 90 and the second counterweight 190 are mounted on the upper rotating body 20B. Note that Figs. 1 and 2 show a state in which the first counterweight 90 and the second counterweight 190 are mounted on the upper rotating body 20B. In this specification, the first counterweight 90 and the second counterweight 190 are collectively referred to as the counterweight 9. A plate-shaped mounting part 71 for mounting a counterweight 9 is provided on the rear end of the rotating frame 7 opposite the support bracket 7a supporting the excavation device 3 (see FIG. 8 described later). The counterweight 9 is fixed to the rear end of the upper rotating body 20B by fastening a fixing bolt 213 to the mounting part 71 on the rotating frame 7.

[0029] A driving unit 50, which allows an operator to drive and operate the traveling unit 5 and the excavation device 3, is provided on the rotating frame 7. The driving unit 50 has a flat floor 58, which is provided on the left side of the front half of the rotating frame 7. A tank unit 59 is provided on the right side of the driving unit 50. The left side of the floor 58 serves as an entrance for the operator to get on and off the driving unit 50. In addition, a prime mover unit 11 including an engine etc. is provided on the rear of the rotating frame 7.

[0030] A canopy 51 is provided on the revolving frame 7 to cover the upper part of the driving section 50. The canopy 51 has a pair of left and right support pillars 52, 52 erected above the prime mover section 11, which is the rear end part of the revolving frame 7, and a roof section 53 supported by the left and right support pillars 52, 52.

[0031] In the driving section 50, a driver's seat support base 55 is provided behind a floor section 58, and a driver's seat 56 is provided on the driver's seat support base 55. A hydraulic oil tank (not shown) that stores hydraulic oil is provided in a tank section 59 provided on the right side of the driving section 50. The hydraulic oil in the hydraulic oil tank is supplied to each hydraulic cylinder, which is a hydraulic actuator equipped in the excavation machine 1.

[0032] Around the driver's seat 56, there are provided an operation panel having various operation parts such as work operation levers for operating the working machine (the excavation device 3 or the soil removal device 4) and switches. Between the driver's seat 56 and the tank section 59 on the right side, there is provided an operation device 100 having a blade lift operation lever 101 for operating the soil removal device 4. In front of the driver's seat 56, there are provided a pair of left and right travel levers 57, 57 extending upward from the floor section 58. The travel operation of the traveling unit 5 is performed by tilting each of the travel levers 57, 57 in the forward and backward directions. A plurality of operation pedals for work are provided on both the left and right sides of the travel levers 57, 57 on the floor section 58.

[0033] In the excavation machine 1 having the above-mentioned configuration, the desired motion and work are performed by the operator seated in the driver's seat 56 appropriately operating the travel levers 57, 57 and the work operation levers. Specifically, for example, the travel levers 57, 57 are operated to cause the traveling section 5 to travel forward and backward in a straight line or turn left and right. Also, the excavation work is performed by the excavation device 3, or the soil removal work or ground leveling work is performed by the soil removal device 4, by operating the work operation lever.

[0034] The counterweight 9 according to this embodiment will be described with reference to Figures 4 to 8. The counterweight 9 comprises a first counterweight 90 and a second counterweight 190. In the following description of the first counterweight 90 and the second counterweight 190, when the first counterweight 90 and the second counterweight 190 are mounted on the upper rotating body 20B, the surface facing the outside of the machine body will be referred to as the front surface (front side), and the surface facing the inside of the machine body will be referred to as the back surface (rear side).

[0035] The first counterweight 90 is made of cast iron and is molded approximately symmetrically in an arc shape with the center in the left-right direction convex outward so as to fit the arc shape of the rear end of the revolving frame 7. The first counterweight 90 also functions as part of the rear cover of the upper revolving body 20B that covers the engine and other components disposed on the revolving frame 7.

[0036] A pair of first insertion holes 91 are provided near the vertical center of the first counterweight 90, one on each side, for inserting fixing bolts 213 for fixing the first counterweight 90 to the mounting portion 71 (see FIG. 8) erected on the revolving frame 7. A first receiving portion 93 having a flat surface for receiving the head of the fixing bolt 213 is provided around each first insertion hole 91. A first exhaust hole 94 is provided below the position of the first insertion hole 91 of the first counterweight 90, corresponding to the outlet of the exhaust pipe 72 through which the exhaust from the engine flows, for releasing the exhaust to the outside of the aircraft. The number and positions of the exhaust holes in the first counterweight 90 are changed as appropriate according to the number and positions of the exhaust pipes 72 of the engine.

[0037] A pair of left and right fastening holes 95 for connecting the second counterweight 190 are provided on the upper side of the first counterweight 90. An internal thread groove is formed on the inner circumferential surface of each fastening hole 95. A male thread groove provided on the tip of a connecting bolt 215 for assembling the second counterweight 190 to the first counterweight 90 is screwed into this female thread groove.

[0038] A first cutout 96 that is concave downward and opens to the front surface is provided at the center of the left and right sides of the upper end surface of the first counterweight 90. A first flat surface 97 that forms the bottom of the concave shape of the first cutout 96 is further provided with a hook hole 98 for hooking a mounting member 200 that is attached to the second counterweight 190 described later.

[0039] The first cutout portion 96 has a horizontal first flat surface 97, side surfaces 96a which are wall surfaces formed on both the left and right sides of the first flat surface 97, and a front surface 96b which is a wall surface formed in front of the first flat surface 97, and is formed as a notched recess with the upper and rear sides open by these surfaces. In the first cutout portion 96, the latch hole 98 is formed so as to open to the upper side in the first flat surface 97 and to communicate with the space below the plate-shaped portion that forms the first flat surface 97.

[0040] The second counterweight 190 is made of cast iron and has the same external shape as the first counterweight 90. It is molded approximately symmetrically in an arc shape with the center in the left-right direction convex outward to match the surface shape of the first counterweight 90.

[0041] A pair of left and right communication holes 191 are provided near the vertical center of the second counterweight 190. The position of the communication holes 191 in the second counterweight 190 corresponds to the position of the first insertion hole 91 in the first counterweight 90. The size of the communication hole 191 is large enough to allow the bolt head of the fixing bolt 213 and a flat washer 214 interposed between the bolt head and the first receiving portion 93 of the first counterweight 90 to pass through. Further below the position of the communication hole 191 in the second counterweight 190, a second exhaust hole 194 for releasing exhaust air from the engine to the outside of the aircraft is provided, just like the first counterweight 90. The position of the second exhaust hole 194 in the second counterweight 190 corresponds to the position of the first exhaust hole 94 in the first counterweight 90.

[0042] A pair of left and right second insertion holes 192 are provided on the upper side of the second counterweight 190, into which connecting bolts 215 that connect the second counterweight 190 to the first counterweight 90 are inserted. Similar to the first insertion holes 91, second receiving portions 193 having flat surfaces that receive the bolt heads of the fixing bolts 213 are provided around each second insertion hole 192. The positions of the second insertion holes 192 in the second counterweight 190 correspond to the positions of the fastening holes 95 in the first counterweight 90.

[0043] A second cutout 196 is provided at the center of the left and right sides of the top end surface of the second counterweight 190. The second cutout 196 is recessed downward and cut out across the thickness of the second counterweight 190. The position of this second cutout 196 on the second counterweight 190 corresponds to the position of the first cutout 96 on the first counterweight 90.

[0044] The second cutout portion 196 has a horizontal second flat surface 197 and side surfaces 196a which are wall surfaces formed on both the left and right sides of the second flat surface 197, and is formed as a notched recess that is open on the top and on both the front and rear sides by these surfaces. The left and right side surfaces 196a are formed in an inclined shape so that the distance between them gradually increases from the bottom to the top.

[0045] The second cutout 196 is provided with a mounting member 200 that is substantially L-shaped in side view and serves as a hook that hooks into the hook hole 98 of the first counterweight 90. The mounting member 200 is formed into an L-shape by bending a plate of a predetermined thickness at a predetermined position by approximately 90 degrees, and has a pair of bolt insertion holes 203 at one end for inserting mounting bolts 201 to mount the mounting member 200 to the second cutout 196. A pair of female threaded holes 195 that communicate with the bolt insertion holes 203 and screw into each of the pair of mounting bolts 201 are drilled in a second flat surface 197 that forms the concave bottom of the second cutout 196. The mounting member 200 is fixed to the second flat surface 197 by fastening the mounting bolts 201 that have passed through the bolt insertion holes 203 of the mounting member 200 to the female threaded holes 195. The mounting member 200 is attached to the second flat surface 197 so that the end of the mounting member 200 opposite the end where the bolt insertion hole 203 is provided faces downward. Note that a flat washer 202, through which the bolt shaft of the mounting bolt 201 passes, is interposed between the bolt head of the mounting bolt 201 and the mounting member 200. In this way, the mounting member 200 is fixed to the upper end surface of the second counterweight 190.

[0046] Furthermore, a hardware mounting portion 204 for mounting an eyebolt 199, which is a lifting hardware, is provided at the end of the mounting member 200 on which the bolt insertion hole 203 is formed. The hardware mounting portion 204 is a through hole that penetrates the mounting member 200, and has an internal thread groove formed on its inner circumferential surface that screws into the external thread groove of the bolt shaft of the eyebolt 199. By screwing the bolt shaft of the eyebolt 199 into the hardware mounting portion 204 of the mounting member 200, the eyebolt 199 is provided on the upper end surface of the second counterweight 190.

[0047] With the above-mentioned configuration, the first counterweight 90 is mounted on the upper rotating body 20B by being directly fixed to the mounting part 71 with the fixing bolts 213. The second counterweight 190 is mounted on the upper rotating body 20B by hanging the mounting member 200 in the hanging hole 98 of the first counterweight 90 (see FIG. 6) and by being indirectly fixed to the mounting part 71 via the first counterweight 90 with the connecting bolts 215.

[0048] The manner in which the counterweight 9 having the first counterweight 90 and the second counterweight 190 configured as above is attached to the upper rotating body 20B will be further described.

[0049] An example will be described in which a first counterweight 90 is initially mounted on the upper rotating body 20B of the excavation machine 1 as a standard weight that balances with the configuration of the work machine, and a second counterweight 190 is further attached as an additional weight in response to a change in the configuration of the work machine due to a replacement of the work tool.

[0050] In the example shown in Fig. 7, the first counterweight 90 is fastened to the upper rotating body 20B by a fixing bolt 213 that passes through the first insertion hole 91 to the mounting part 71 (see Fig. 8) that stands on the rotating frame 7. When attaching the second counterweight 190 to this first counterweight 90, first, the mounting member 200 and the eyebolt 199 are attached to the second notch 196 of the second counterweight 190. Next, the downward end of the substantially L-shaped mounting member 200 of the second counterweight 190 is fitted into the hook hole 98 of the first counterweight 90. At this time, the first notch 96 of the first counterweight 90 is disposed opposite the second notch 196 of the second counterweight 190 (see Fig. 6). When moving the second counterweight 190 towards the first counterweight 90, it may be hoisted by a crane or the like using eyebolts 199, if necessary.

[0051] As shown in a partial cross section in Figure 6, when the end of the second counterweight 190 bent downwards of the mounting member 200, which has a substantially L-shaped cross section, is hooked into the hook hole 98 of the first counterweight 90, the first flat surface 97 and the second flat surface 197 are at approximately the same height in the first notch 96 of the first counterweight 90 and the second notch 196 of the second counterweight 190, which face each other. At this time, the load of the second counterweight 190 is received by the inner wall surface of the hook hole 98 (the inner wall surface having the same width as the plate width of the mounting member 200) and the first flat surface 97 via the mounting member 200. A moment of force acts around the contact point between the mounting member 200 and the first notch 96, and the back surface of the second counterweight 190 abuts against the front surface of the first counterweight 90.

[0052] When the second counterweight 190 is attached to the first counterweight 90 via the mounting member 200, the pair of first insertion holes 91 and the pair of communication holes 191, the pair of fastening holes 95 and the pair of second insertion holes 192, and the first exhaust hole 94 and the second exhaust hole 194 are all in communication with each other. In this way, the mounting member 200 also functions as an alignment member for aligning the holes in the first counterweight 90 and the second counterweight 190 that are in a corresponding positional relationship.

[0053] The connecting bolts 215 are sequentially inserted from the aligned second insertion holes 192 into the fastening holes 95, and the tips of the connecting bolts 215 are screwed into the fastening holes 95. At this time, the bolt heads of the connecting bolts 215 come into contact with the second receiving portions 193 of the second counterweight 190 via the flat washers 216. In this way, the second counterweight 190 is fixed to the first counterweight 90 by the connecting bolts 215 that pass through from the second insertion holes 192 to the fastening holes 95.

[0054] Also, an example will be described in which a first counterweight 90 and a second counterweight 190 are simultaneously attached to the upper rotating body 20B as weights that balance the configuration of the work machine.

[0055] In the example shown in Fig. 8, the first counterweight 90 and the second counterweight 190 are assembled in advance. The first counterweight 90 and the second counterweight 190 are assembled, for example, by the following procedure. First, the first counterweight 90 is placed on a workbench or the like in a substantially upright position, and the back surface of the second counterweight 190 to which the mounting member 200 and eyebolt 199 are attached is placed on the first counterweight 90. At this time, the end of the mounting member 200 of the second counterweight 190 is fitted into the hook hole 98 of the first counterweight 90. This aligns the holes in the corresponding positions, i.e., the pair of first insertion holes 91 and the pair of communication holes 191, the pair of fastening holes 95 and the pair of second insertion holes 192, and the first exhaust hole 94 and the second exhaust hole 194.

[0056] Next, the connecting bolt 215 is inserted from the aligned second insertion hole 192 into the fastening hole 95, and the tip of the connecting bolt 215 is screwed into the fastening hole 95. This completes the assembly of the first counterweight 90 and the second counterweight 190.

[0057] When the counterweight 9, which is an integrated unit of the first counterweight 90 and the second counterweight 190, is attached to the upper rotating body 20B, the counterweight 9 is moved toward the rear end of the rotating frame 7. At this time, the counterweight 9 is lifted by a crane or the like via the eyebolt 199. Thereafter, the fixing bolt 213 is inserted from the communication hole 191 to the first insertion hole 91 in this order, and the tip of the fixing bolt 213 is screwed into the corresponding female screw hole provided in the mounting part 71 erected on the rotating frame 7. The bolt head of the fixing bolt 213 that has passed through the communication hole 191 abuts against the first receiving part 93 of the first counterweight 90 via the flat washer 214. In this way, the counterweight 9 is fastened to the upper rotating body 20B by the fixing bolt 213 that has passed through the communication hole 191 and penetrated from the first insertion hole 91 to the mounting part 71.

[0058] Since the mounting member 200 is detachably attached by the mounting bolt 201, if there is no need to remove the counterweight 9 after the counterweight 9 is attached to the upper rotating body 20B, the mounting bolt 201 may be removed and the mounting member 200 may be removed from the second counterweight 190. Similarly, the eye bolt 199 may also be removed after the counterweight 9 is attached to the upper rotating body 20B.

[0059] With the counterweight 9 of this embodiment configured as described above, the mounting members 200 can be used to easily position the pair of communication holes 191 in the second counterweight 190 relative to the pair of first insertion holes 91 in the first counterweight 90, and the pair of second insertion holes 192 in the second counterweight 190 relative to the pair of fastening holes 95 in the first counterweight 90. Therefore, the second counterweight 190 can be assembled to the first counterweight 90 to form a unit, as described with reference to Figure 8.

[0060] Furthermore, in the unitized counterweight 9, a pair of communication holes 191 provided in the second counterweight 190 communicate with the first insertion hole 91 of the first counterweight 90 through the bolt head and flat washer 214 of the fixing bolt 213. Therefore, an operator can insert the fixing bolt 213 into the first insertion hole 91 from the outside of the second counterweight 190 through the communication hole 191, in the same way as when attaching only the first counterweight 90 to the upper rotating body 20B, and fasten it to the mounting part 71 of the revolving frame 7. In this way, in this embodiment, the operator only needs to perform the same work when attaching only the first counterweight 90 to the upper rotating body 20B and when attaching the unitized counterweight 9 to the upper rotating body 20B, improving the workability of attaching and detaching the counterweight.

[0061] The second counterweight 190 is provided with an eyebolt 199. This allows lifting by a crane or the like in both cases of attaching the second counterweight 190 to the first counterweight 90 already mounted on the upper rotating body 20B and attaching the unitized counterweight 9 to the upper rotating body 20B. Conventionally, the counterweight has a weight that can balance with the working machine, and is moved to the height position of the upper rotating body 20B located above the lower traveling body 20A and attached. Conventionally, in order to lift the counterweight to a predetermined height with a crane, for example, a slinging wire must be hung on the counterweight and the wire must be removed in the middle of attaching the counterweight. In this embodiment, the counterweight 9 or the second counterweight 190 is lifted via the eyebolt 199, so slinging work is not necessary and the counterweight can be attached and detached more easily.

[0062] The above-mentioned embodiment is an example of the present invention, and the construction machine according to the present invention is not limited to the above-mentioned embodiment. Therefore, even if it is other than the above-mentioned embodiment, various modifications are possible according to the design, etc., as long as they do not deviate from the technical idea of ​​the present invention. Furthermore, the effects described in this disclosure are merely examples and are not limited, and other effects may be obtained.

[0063] In the above-described embodiment, the mounting member 200 is formed into an L-shape by bending a plate of a predetermined thickness at a predetermined position by approximately 90 degrees, but is not limited thereto. For example, the mounting member 200 may be formed by welding the ends of two metal plates to form an L-shape, or may be formed by cutting a metal block into an approximately L-shape when viewed from the side.

[0064] In the above embodiment, the mounting member 200 is detachably attached by the mounting bolt 201, but this is not limited thereto. For example, the mounting member 200 may be integrated with the second counterweight 190 by welding. That is, the mounting member 200 may be connected to the second counterweight 190 by any method other than bolt fastening, such as welding, as long as the mounting member 200 can support the weight of the second counterweight 190 or the counterweight 9 in which the first counterweight 90 and the second counterweight 190 are assembled. Furthermore, the shape of the mounting member 200 is not limited to a substantially L-shaped shape when viewed from the side. That is, the mounting member 200 may be detachably engaged with the shape of the first notch 96 in the first counterweight 90 and the latch hole 98 provided therein. [Explanation of symbols]

[0065] 1. Excavation machine (construction machine) 3. Drilling Rig 5 Running part 6 Aircraft Frame 7 Swivel Frame 9 Counterweight 50 Driving Department 55 Driver's seat 59 Tank section 20A Undercarriage 20B Upper rotating body (airframe) 71 Mounting part 72 Exhaust pipe 90 First counterweight 91 First insertion hole 94 First exhaust hole 95 Fastening hole 96 First notch 97 1st flat surface 98 Latch hole 190 Second counterweight 191 Communication hole 192 Second insertion hole 194 Second exhaust hole 195 Bolt insertion hole 196 Second notch 197 Second flat surface 199 Eyebolt 200 Mounting material 201 Mounting bolt 203 Bolt insertion hole 204 Metal fitting attachment part 213 Fixing bolt 215 Connecting bolt

Claims

1. A construction machine including a lower traveling body, an upper rotating body rotatably supported on the lower traveling body, and a work implement rotatably supported in front of the upper rotating body, The upper rotating body is a first counterweight fixed by a screw fastener to a mounting portion provided on a rear portion of a revolving frame that revolves relative to the lower traveling body; a second counterweight fixed to the first counterweight by a screw fastener; The first counterweight has a hook hole on an upper portion thereof, A construction machine characterized in that the second counterweight is provided with a hanging portion that is hung by being inserted into the hanging hole.

2. A first notch portion having a concave shape extending downward from the upper end surface of the first counterweight is formed in the upper end surface of the first counterweight, and the hook hole is provided in the first notch portion.

2. A construction machine according to claim 1, characterized in that a second cutout portion having a concave shape extending downward from the upper end surface of the second counterweight is provided on the upper end surface of the second counterweight, and the hook portion is provided in the second cutout portion.

3. The hook portion is an attachment member having an L-shape in a side view, 3. A construction machine according to claim 1, wherein one end of the mounting member is connected to the second counterweight, and the other end of the mounting member is inserted into the hook hole.

4. The first counterweight is provided with an insertion hole into which a screw fastener for fixing the first counterweight to the mounting portion is inserted, 4. The construction machine according to claim 1, wherein the second counterweight is provided with a communication hole that communicates with the insertion hole.

5. 5. The construction machine according to claim 1, wherein the hook portion is detachably fixed to the second counterweight.

6. 6. The construction machine according to claim 1, wherein the hanging portion has a metal fitting attachment portion for attaching a lifting metal fitting.

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