Work machine

Abstract

To easily and reliably conduct structures together.SOLUTION: The present invention includes an electrical component, at least two structures each having electrical conductivity, and a conductive screw member that electrically connects the at least two structures to each other.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a work machine equipped with electrical components.

Background Art

[0002] Conventionally, work machines such as backhoes include a plurality of structures that make up a frame, and various electrical components that receive power supply from a battery. The structures are made of a rigid metal material and support various equipment. The electrical components are also attached to predetermined positions of the structures and supported by the structures, and the plurality of structures are electrically connected to each other via a ground wire.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when electrically connecting the structures to each other with a ground wire, components such as a ground wire and a screw are required, so the number of components increases, and the man-hours required for connecting the ground wire to the structure also increase.

[0005] Therefore, the present invention provides a work machine that can reduce the number of components and the man-hours during installation, and can easily and surely conduct electricity between the structures.

Means for Solving the Problems

[0006] The work machine of the present invention includes electrical components, at least two structures each having conductivity, and a conductive screw member that connectably connects the at least two structures to each other.

Effects of the Invention

[0007] According to the present invention, the number of parts and the man-hours for installation can be reduced, and the structures can be easily and surely electrically connected to each other.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0009] Hereinafter, a working machine according to an embodiment of the present invention will be described with reference to the drawings.

[0010] The work machine of this embodiment is a backhoe that can travel. In the following description, the straight-ahead direction (the direction of forward and backward travel) of the work machine shall be referred to as the first direction. Also, the forward side in the first direction of the work machine shall be referred to as the front side, and the backward side in the first direction of the work machine shall be referred to as the rear side. Furthermore, the direction orthogonal to both the first direction and the vertical direction shall be referred to as the second direction, and the vertical direction shall be referred to as the third direction.

[0011] As shown in FIGS. 1 to 3, the work machine 1 includes an electrical component EP (see FIGS. 1 and 3), a plurality of structures 30, 31, 32, 33, 34 each having conductivity, and a conductive screw member 35 (see FIG. 4) that electrically connects the structures 30, 31, 32, 33, 34 to each other.

[0012] More specifically described, as shown in FIG. 1, the work machine 1 includes a traveling device 2, a machine body 3 supported by the traveling device 2, the machine body 3 including an electrical component EP and a plurality of structures 30, 31, 32, 33, 34, and a working device 4 supported by the machine body 3. Also, the work machine 1 includes a battery 5 (5a, 5b). Furthermore, the work machine 1 includes a hydraulic system that operates the traveling devices 2, 2 and the working device 4, and a prime mover 6 that drives a hydraulic pump included in the hydraulic system. In this embodiment, an electric motor is used as the prime mover 6, but it is not limited thereto, and the prime mover 6 may be an engine. Also, in this embodiment, the traveling devices 2, 2 and the working device 4 are driven hydraulically, but it is not limited thereto, and part or all of the traveling devices 2, 2 and the working device 4 may be driven electrically.

[0013] The work machine 1 includes a pair of traveling devices 2, 2 arranged at intervals in the second direction. A crawler-type traveling device or a tire-type traveling device is adopted for each of the pair of traveling devices 2, 2. In this embodiment, a crawler-type traveling device is adopted for the pair of traveling devices 2, 2.

[0014] The work machine 1 includes a shovel device 4a and a dozer device 4b as the working device 4.

[0015] The vehicle body 3 has a plurality of structures 30, 31, 32, 33, 34 that constitute a frame (skeleton) for supporting various equipment including electrical components EP. As shown in FIGS. 1 and 2, the plurality of structures 30, 31, 32, 33, 34 are mechanically integrated by being fastened with screw members. In the present embodiment, as shown in FIGS. 1 and 2, the vehicle body 3 includes, as structures, a traveling frame 30 (see FIG. 1) supported by a pair of traveling devices 2, 2, a swivel frame 31 (see FIG. 1) that can swivel around an axis CL extending in the vertical direction on the traveling frame 30, a driver's seat DS (see FIG. 1) disposed on the swivel frame 31, a driver's seat protection mechanism 32 that covers and protects the driver's seat DS, a bonnet 33 that protects equipment such as the prime mover 6, and a support frame 34 that supports the bonnet 33.

[0016] The traveling frame 30 is manufactured by welding and machining a metal material and has a structure in which a coating is applied to the surface of the metal substrate (metal material). As shown in FIG. 1, the traveling frame 30 has a main body portion 300 and a pair of connecting portions 301 that extend outward from both side ends of the main body portion 300 in the second direction and to which the traveling devices 2, 2 are respectively attached. The main body portion 300 is disposed between the pair of traveling devices 2, 2. The traveling frame 30 of the present embodiment has a first connecting portion 302 to which a dozer device 4b as a working device 4 is connected, and the first connecting portion 302 is connected to one end portion on the front side of the main body portion 300. On the upper surface of the main body portion 300, a swivel bearing BR having a swivel center line CL extending in the vertical direction is fixed with male screw members.

[0017] The swivel frame 31 is manufactured by welding and machining a metal material and has a structure in which a coating is applied to the surface of the metal substrate (metal material). Specifically, as shown in FIG. 3, the swivel frame 31 has a base plate 310 and a second connecting portion 311 to which a shovel device 4a as a working device 4 is connected, and the second connecting portion 311 is connected to one end portion of the base plate 310 in the first direction. As shown in FIG. 3, the swivel frame 31 has a base plate 310 and a second connecting portion 311 to which a shovel device 4a as a working device 4 is connected, and the second connecting portion 311 is connected to one end portion of the base plate 310 in the first direction.

[0018] A swivel bearing BR fixed to the upper surface of the main body 300 is fixed to the base plate 310. As a result, the base plate 310 (swivel frame 31) is rotatable relative to the traveling frame 30 around an axis (swivel center of the swivel bearing BR) CL extending in the vertical direction.

[0019] On the upper surface of the base plate 310, ribs 312 and columns 313 that support equipment arranged above or another structure (for example, the driver's seat protection mechanism 32, etc.) are erected. Also, in the present embodiment, a plurality of fixing portions 314... for fixing the support legs 340... of the support frame 34 described later are provided on the upper surface of the base plate 310.

[0020] More specifically, the driver's seat DS and the driver's seat protection mechanism 32 are arranged in the front region FA in the first direction of the base plate 310 (hereinafter referred to as the front region FA), and equipment such as the prime mover 6 is arranged in the rear region BA in the first direction of the base plate 310 (hereinafter referred to as the rear region BA). In the front region FA, columns 313 that support a plate-shaped step on which the driver's seat DS is arranged are erected. Note that some of the ribs 312 and columns 313 are screwed (fixed) to the base plate 310, and some are fixed to the base plate 310 by welding.

[0021] As shown in FIG. 1, the driver's seat protection mechanism 32 of the present embodiment is a so-called cabin that covers the entire driver's seat DS and protects the operator sitting on the driver's seat DS. The cabin (driver's seat protection mechanism) 32 includes a frame that is a structure with a coating applied to the surface of a metal base (metal material). Specifically, as shown in FIGS. 1 and 2, the frame of the cabin 32 includes a roof 320 that covers the upper part of the driver's seat DS and support columns 321... that support the roof 320. A pair of support columns 321... are provided on each of the front and rear sides. The pair of support columns 321... arranged on the front side are directly supported by the swivel frame 31. The pair of support columns 321... arranged on the rear side are indirectly supported by the swivel frame 31 via the support frame 34 (see FIG. 2). That is, the support frame 34 is connected to the swivel frame 31 and supports other members.

[0022] In front of the driver's seat protection mechanism 32, a front window FW is arranged, a rear window RW is arranged at the back, an openable door 322 and a side window SW are arranged on one side (see Fig. 1), and a side window SW is arranged on the other side (see Fig. 2). Thus, the cabin 32 surrounds the driver's seat DS and defines the driver's cab DR. Inside the cabin 32 (driver's cab DR), in addition to various meters and switches, electrical components such as a display device (monitor) are arranged and fixed to support columns 321... etc.

[0023] As shown in Figs. 2 and 3, in the rear region BA of the base plate 310, the prime mover 6 and a driving battery 5b described later are arranged. Accordingly, as shown in Fig. 3, in the rear region BA of the base plate 310, reinforcing ribs 312 and ribs 312 for supporting the prime mover 6 and the driving battery 5b are erected. The reinforcing ribs 312 and the ribs 312 for supporting the prime mover 6 and the driving battery 5b are fixed to the upper surface of the base plate 310 by welding. Further, in the rear region BA of the base plate 310, a plurality of fixing parts 314... for fixing a support frame 34 that supports a bonnet 33 covering the prime mover 6 and the driving battery 5b are provided. Each of the plurality of fixing parts 314... is fixed to the base plate 310 by welding. The upper surfaces of the plurality of fixing parts 314... are arrangement surfaces for arranging support legs 340... of the support frame 34 described later and are flat.

[0024] In the present embodiment, the fixing parts 314... are arranged at five locations according to the number of the support legs 340.... The metal substrate of the fixing parts 314... is a metal plate having a rectangular shape in plan view and is fixed to the upper surface of the metal substrate of the base plate 310 directly or indirectly by welding. Each of the fixing parts 314... is arranged on the boundary (shown by a two-dot chain line in the figure) of a rectangular area SA that fits within the rear region BA of the base plate 310. The rectangular area SA is defined by a pair of first straight lines L1, L1 extending in the first direction and a pair of second straight lines L2, L2 extending in the second direction and connecting to the pair of first straight lines L1, L1.

[0025] In each of the plurality of fixing parts 314…, a pair of screw holes (hereinafter referred to as first screw holes) SH1, SH1 spaced apart in the second direction are drilled in the vertical direction. This pair of first screw holes SH1 is for screwing a male screw member (fastening male screw member) S for mechanically connecting the support legs 340…. The first screw holes SH1 of each of the plurality of fixing parts 314… are arranged on the boundary of the rectangular region SA or inside the boundary of the rectangular region SA.

[0026] Among the plurality of fixing parts 314…, at least one of the fixing parts 314… is provided with a screw hole (hereinafter referred to as a second screw hole) SH2 for screwing a later-described guiding screw member, which is arranged between the pair of first screw holes SH1 and inside the boundary of the rectangular region SA. In the present embodiment, the second screw hole SH2 is provided only in one of the two fixing parts 314… on the front side. In the present embodiment, the second screw hole SH2 is arranged at the middle (center) position between the pair of first screw holes SH1 and is located inside the rectangular region SA outside the second straight lines L2, L2.

[0027] As shown in FIG. 5, the swing frame 31 has a coating film PL by painting on the surface of the metal substrate MB. In the present embodiment, the swing frame 31 is provided with through holes, screw holes, openings, etc. in addition to the first screw holes SH1 and the second screw holes SH2 at appropriate positions, and the inner peripheral surfaces of these are also painted. That is, the swing frame 31 is painted after machining, and a coating film PL of paint is formed not only on the outer surfaces (front and back surfaces) of the base plate 310 and the fixing parts 314… but also on the inner peripheral surfaces of the holes, screw holes (including the first screw holes SH1 and the second screw holes SH2), and openings.

[0028] As shown in FIG. 2, the bonnet 33 covers devices such as the prime mover 6 disposed on the base plate 310. In the present embodiment, the bonnet 33 covers the devices such as the prime mover 6 from above, side, and rear. Specifically, the bonnet 33 of the present embodiment includes a first bonnet 33a that covers the devices such as the prime mover 6 from above, a pair of second bonnets 33b, 33b that cover the devices such as the prime mover 6 from the side, and a third bonnet 33c that covers the devices such as the prime mover 6 from the rear. Also, the electrical components (for example, relay devices, electric fans, etc.) EP are attached to the support frame 34 and disposed at a predetermined position.

[0029] The support frame 34 is manufactured by welding and machining a metal material, and is a structure in which a surface of a metal substrate (metal material) is painted. Specifically, as shown in FIG. 3, the support frame 34 includes a plurality of support legs 340... each extending in the vertical direction, and a leg connecting portion 341 connecting upper ends of the plurality of support legs 340.... The plurality of support legs 340... are disposed corresponding to the fixing portions 314... of the swivel frame 31. That is, five support legs 340... are provided corresponding to the fixing portions 314....

[0030] Two of the five support legs 340... are disposed at intervals in the second direction on the front side in the first direction. Two of the remaining three support legs 340... are disposed at intervals in the second direction on the rear side in the first direction, and the remaining support leg 340... is disposed between the front support legs 340... and the rear support legs 340....

[0031] In the present embodiment, among the three support legs 340... on one side in the second direction, the two support legs 340... on the front side (the two support legs 340... disposed at intervals in the first direction) are connected by a connecting beam 342 extending in the first direction. The connecting beam 342 is on the rear side Half is perpendicular to the rear support leg 340..., the front half is inclined downward toward the front, and the tip is connected to the front support leg 340.... These support legs 340... and the connecting beam are integrally formed by bending a metal strip. To the upper end of the remaining one of the three support legs 340... on one side in the second direction (one support leg 340... on the rear side), a vertical beam (referred to as the first vertical beam) 343 extending forward is connected. In this embodiment, the first vertical beam 343 and one support leg 340 on the rear side are integrally formed by bending a metal strip.

[0032] In this embodiment, among the two support legs 340... on the other side in the second direction, one support leg 340... on the front side is connected to a vertical beam (hereinafter referred to as the second vertical beam) 344 extending rearward. This support leg 340... and the second vertical beam 344 are integrally formed by bending a metal strip. Among the two support legs 340... on the other side in the second direction, one support leg 340... on the rear side is connected to a vertical beam (hereinafter referred to as the third vertical beam) 345 extending forward. This support leg 340... and the third vertical beam 345 are integrally formed by bending a metal strip.

[0033] The leg connection part 341 includes a plurality of cross beams 341a, 341b extending in the second direction. Each of the plurality of cross beams 341a, 341b is made of metal and is arranged side by side in the first direction. The plurality of cross beams 341a, 341b are arranged so as to straddle the connecting beam 342, the first vertical beam 343, the second vertical beam 344, and the third vertical beam 345, and are connected to the connecting beam 342, the first vertical beam 343, the second vertical beam 344, and the third vertical beam 345 by welding. That is, the plurality of support legs 340... are mechanically and electrically connected via the plurality of cross beams 341a, 341b, the connecting beam 342, the first vertical beam 343, the second vertical beam 344, and the third vertical beam 345.

[0034] Each of the plurality of support legs 340... includes a support plate 340a disposed on a fixing portion 314... of the swivel frame 31 as shown in FIG. 4, and a leg body 340b connected to the support plate 340a, the leg body 340b extending upward from the support plate 340a. The planar shape of the support plate 340a is set according to the planar shape of the fixing portion 314... to which the support plate 340a is fixed. Further, as shown in FIG. 6, a first through hole H1 corresponding to a first screw hole SH1 of the fixing portion 314... to which the support plate 340a is fixed is formed in the support plate 340a. That is, each support plate 340a has a pair of first through holes H1 spaced apart in the second direction. As shown in FIG. 6, the first through hole H1 is set to a hole diameter through which a male screw member S screwed into the first screw hole SH1 can be inserted. In the present embodiment, the support plate 340a of the support leg 340... corresponding to one of the two fixing portions 314... on the front side has a second through hole H2 corresponding to a second screw hole SH2 (see FIGS. 4 and 6). The second through hole H2 is set to a hole diameter through which a guiding screw member 35 screwed into the second screw hole SH2 can be inserted.

[0035] The support plate 340a of each support leg 340... is mechanically fixed to the swivel frame 31 (fixing portion 314...) by screwing a male screw member S inserted through the first through hole H1 into the first screw hole SH1 of the fixing portion 314.... Further, the support plate 340a having the second through hole H2 is electrically connected to the swivel frame 31 (fixing portion 314...) by screwing a guiding screw member 35 inserted through the second through hole H2 into the second screw hole SH2.

[0036] The support frame 34 configured as described above supports other structures 32, 33 placed on the leg connection portion 341 (cross beam 341a) at a predetermined height position. In the present embodiment, the cabin 32 (rear support column 321...) is fixed to the cross beam 341a via a male screw member. Further, the support frame 34 (leg connection portion 341) supports the bonnet 33 (first bonnet 33a) at a predetermined position via a metal fitting.

[0037] The work machine 1 includes, as the battery 5, a battery 5a that supplies power to the electrical components EP and a driving battery 5b that supplies power to the prime mover 6. The battery 5a that supplies power to the electrical components EP is disposed in the rear region BA, and the driving battery 5b is disposed on the rear region BA of the base plate 310 together with the prime mover (electric motor). Each of the batteries 5a and 5b is fixed to the base plate 310 at a fixed position via a fixing fitting.

[0038] The electrical components EP of the work machine 1 of the present embodiment include a headlight that illuminates the front of the work machine 1, a solenoid valve that controls the flow of hydraulic oil in the hydraulic system, a control board that controls the prime mover 6, a relay device (switch device) that opens and closes the electric circuit of the electrical system, an electric fan for cooling, and various other components. These electrical components EP are electrically connected to the battery 5 (5a) and operate by power supplied from the battery 5 (5a). Further, since an electric motor is adopted as the prime mover 6 of the work machine 1 of the present embodiment, the prime mover (electric motor) 6 is connected to the driving battery 5 (5b) and operates by power supplied from the driving battery 5 (5b). And these electrical components EP and the prime mover 6 are arranged in appropriate positions according to the purpose of use and the like, and are fixed to the structures 31, 32, 33, 34 in the vicinity thereof.

[0039] The work machine 1 of the present embodiment includes a conductive screw member 35 that electrically connects two or more connected structures 31, 32, 33, 34 to make them equipotential. More specifically, the work machine 1 includes a number of male screw members S separately from the conductive screw member 35. The male screw member S other than the conductive screw member 35 is a general male screw member (hexagon bolt) that ensures the mechanical connection strength between the structures 30, 31, 32, 33, 34. On the other hand, the conductive screw member 35 that makes two or more structures 30, 31, 32, 33, 34 (structures 30, 31, 32, 33, 34 having a coating film PL as an insulating layer on the surface layer) equipotential is configured to be able to electrically connect the structures 30, 31, 32, 33, 34 to each other.

[0040] Each of the plurality of structures 30, 31, 32, 33, 34 includes, as described above, a metal substrate MB and a coating film PL formed on the metal substrate MB. The coating film PL on the metal substrate (metal material) MB is also formed on the inner peripheral surface of the via hole and the inner peripheral surface of the screw hole.

[0041] Therefore, as shown in FIG. 5, when the structures 31 and 34 are overlapped with each other, since the coating film PL (insulating layer) PL is interposed between the structures 31 and 34, electrical connection at the contact surface between the structures 31 and 34 is not ensured. Further, since there is also a coating film PL on the inner peripheral surface of the second screw hole SH2, even if a general male screw member S is screwed into the second screw hole SH2, the coating film PL remains between the thread on the inner peripheral surface of the second screw hole SH2 and the male screw member (thread) S, and electrical connection between the structures 31 and 34 here is not ensured.

[0042] In view of such a situation, in the working machine 1 of the present embodiment, the conductive screw member 35 has peeling portions 350a and 350b for peeling the insulating layer (coating film PL) PL that inhibits electrical connection between the structures 31 and 34, as shown in FIG. 7.

[0043] More specifically, the conductive screw member 35 is formed by molding a conductive metal material (for example, a stainless alloy). The conductive screw member 35 includes a shaft portion 350 having a thread screwed into at least one of the structures 31 and 34. Further, the conductive screw member 35 includes a head portion 351 provided at the base end portion of the shaft portion 350 and having a seating surface Sa that contacts one of the structures 31 and 34. That is, the conductive screw member 35 includes the shaft portion 350 and the head portion 351 connected to one end of the shaft portion 350. A thread is formed in a spiral shape on the outer periphery of the shaft portion 350. The conductive screw member 35 has a smaller diameter than other male screw members (fastening male screw members) S. That is, the shaft portion 350 of the conductive screw member 35 has a smaller diameter than the shaft portion of other male screw members (fastening male screw members) S.

[0044] The head 351 of the guiding screw member 35 is formed to be engageable with a tool such as a wrench or a driver. Specifically, the head 351 is formed in a polygonal shape in a plan view, or a hole in a polygonal shape in a plan view, or a groove in a linear shape (minus (-) shape) in a plan view, or a groove in a cross shape (plus (+) shape) in a plan view. That is, the guiding screw member 35 is in the form of a hexagon screw, a screw with a hexagonal socket, a plus screw, a minus screw, or a combination thereof. The head 351 of the guiding screw member 35 in the present embodiment is formed in a hexagonal shape in a plan view, and the appearance of the guiding screw member 35 is in the form of a so-called hexagon screw.

[0045] The head 351 is set to have a larger diameter than the shaft portion 350. The surface Ca where the shaft portion 350 of the head 351 is connected includes a connection region Ja with the shaft portion 350 and an annular region Sa surrounding the connection region Ja. The annular region Sa is a so-called seating surface Sa that faces or is in close contact with the surface of the structure 34 in a state where the shaft portion 350 is screwed into the second screw hole SH2.

[0046] The guiding screw member 35 (conductive member) has at least one of a peeling structure for peeling the coating film PL at the contact portion with the structures 31 and 34 and a contact portion that penetrates the coating film PL and contacts the metal substrate MB of the structures 31 and 34.

[0047] In the present embodiment, the guiding screw member 35 has peeling structures 350a and 350b for peeling the coating film PL on the outer peripheral surface of the shaft portion 350 and on the seating surface Sa (contact portion with the structures 31 and 34) to expose the metal substrate MB (bringing the guiding screw member 35 into contact with the metal substrate MB).

[0048] Specifically, the conductive screw member 35 has a first peeling portion 350a as a peeling structure that peels off the coating film PL (the coating film PL on the inner peripheral surface (thread ridge) of the screw hole) of one of the two superposed structures 31 and 34 to expose the metal substrate MB. The first peeling portion 350a is disposed on the outer periphery of the shaft portion 350. In the present embodiment, the conductive screw member 35 has a plurality of first peeling portions 350a that partially protrude from the outer surface of the thread ridge of the shaft portion 350 and are formed at intervals in the circumferential direction. The first peeling portion 350a is a protrusion that partially protrudes from the thread ridge. That is, the peeling structure (the first peeling portion 350a) is a protrusion that protrudes radially outward from the thread ridge to the shaft portion 350. In the present embodiment, the first peeling portion 350a is a protrusion that protrudes in a burr shape by partially deforming the thread ridge into a concave shape. By screwing the shaft portion 350 into the second screw hole SH2, the first peeling portion 350a peels off (scrapes off) the coating film PL on the inner peripheral surface of the thread ridge, and exposes the conductive metal substrate MB of the structure 31 (the fixing portion 314 on the base plate 310 of the swivel frame 31).

[0049] Thereby, by tightening the conductive screw member 35, the conductive thread ridge of the conductive screw member 35 is in close contact with the conductive metal substrate MB of the thread ridge of the second screw hole SH2 of the structure 31, and the conductive screw member 35 and the structure 31 (the metal substrate MB of the swivel frame 31) are electrically connected (in a conductive state). In the present embodiment, the plurality of first peeling portions 350a are arranged at equal intervals in the circumferential direction. In the present embodiment, the plurality of first peeling portions 350a are arranged in alignment along the direction in which the axis of the shaft portion 350 extends (in the figure, an axis inclined with respect to the axis).

[0050] The conductive screw member 35 has, in addition to the first peeling portion 350a, a second peeling portion 350b that peels off the coating film PL (the coating film PL on the outer surface) of the other structure 34 among the two overlapped structures 31 and 34 to expose the metal substrate MB. The second peeling portion 350b is provided on the seating surface Sa of the head portion 351. The second peeling portion 350b protrudes outward from the seating surface Sa and tapers as it moves away from the seating surface Sa. That is, the second peeling portion 350b protrudes straight in the axial direction of the shaft portion 350. In the present embodiment, the second peeling portion 350b is formed in a conical shape.

[0051] By screwing and tightening the shaft portion 350 into the screw hole, the conductive screw member 35 brings the seating surface Sa into contact with the outer surface of the structure 34 in the same manner as a general male screw member S. By screwing and tightening the shaft portion 350 into the screw hole, the seating surface Sa approaches and contacts the outer surface of the structure 34. At this time, the tip of the second peeling portion 350b contacts the structure 34 ahead of the seating surface Sa and further moves toward the structure 34 side while rotating around the axis of the shaft portion 350. As a result, the coating film PL on the surface layer of the structure 34 is scraped off by the second peeling portion 350b, the metal substrate MB is exposed, and the second peeling portion 350b further contacts the metal substrate MB. When a contact portion is adopted instead of the second peeling portion 350b, the contact portion is formed in a conical shape or a needle shape and protrudes in a state of being inclined downward in the circumferential direction from the seating surface Sa. Thereby, when the contact portion moves toward the structure 34 side while rotating around the axis of the shaft portion 350, it obliquely pierces the coating film PL, penetrates the coating film PL, and contacts the metal substrate MB.

[0052] As described above, the electrical component EP is attached to the support frame 34. Also, various electrical components EP such as solenoid valves included in the hydraulic system are attached to the swivel frame 31 as well. Here, the connection between the swivel frame 31 and the support frame 34 will be described as an example. In the present embodiment, the shaft portion 350 of the conductive screw member 35 is inserted into the second through hole H2 in the support plate 340a of the support frame 34 which is one of the structures 34, and is screwed into the second screw hole SH2 of the fixing portion 314... of the swivel frame 31 which is the other structure. That is, when the conductive screw member 35 with the shaft portion 350 inserted through the second through hole H2 is screwed into the second screw hole SH2, the shaft portion 350 advances in the axial direction while rotating around the axis. At this time, the first peeling portion 350a moves along the thread while peeling the coating film PL on the inner peripheral surface of the second screw hole SH2. As a result, the coating film PL in the screwing range X of the shaft portion 350 (the inner peripheral surface of the second screw hole SH2 where the conductive screw member 35 is screwed) is peeled off and removed, and the metal substrate MB is exposed. Thereby, the thread or the first peeling portion 350a of the shaft portion 350 of the conductive screw member 35 comes into contact with or presses against the metal substrate MB of the support plate 340a.

[0053] Also, as the shaft portion 350 rotates around the axis and advances in the axial direction, the seating surface Sa of the head portion 351 approaches the outer surface (upper surface) of the support plate 340a of the support frame 34 which is one of the structures 34, and the second peeling portion 350b comes into contact with the upper surface of the support plate 340a. Then, since the head portion 351 advances toward the support plate 340a side while rotating following the screwing of the shaft portion 350, the second peeling portion 350b scrapes off the coating film PL on the outer surface of the support plate 340a. As a result, the metal substrate MB of the support plate 340a is exposed, and at least the second peeling portion 350b of the seating surface Sa of the head portion 351 and the second peeling portion 350b comes into contact with or presses against the metal which is the substrate.

[0054] In addition, when the hardness of the material of the conductive screw member 35 is higher (harder) than the hardness of the substrate (metal) of the support plate 340a, in the state where the seating surface Sa is in contact with the support plate 340a, the second peeling portion 350b comes into contact with the substrate of the support plate 340a in a state of biting into it.

[0055] In this way, the shaft portion 350 of the conductive screw member 35 contacts or presses against the metal substrate MB of one of the structures 31, and the head portion 351 of the conductive screw member 35 contacts or presses against the metal substrate MB of the other structure 34. Thus, the conductive screw member 35 mechanically fastens the swivel frame 31 (fixed portion 314...) and the support frame 34 while electrically connecting them.

[0056] In the present embodiment, the conductive screw member 35 is disposed at a position corresponding to the intermediate (central) position between a pair of first screw holes SH1 into which a general male screw member S is screwed, and is screwed into a second screw hole SH2 located within a rectangular region SA outside the second straight lines L2, L2. Therefore, a general male screw member (fastening male screw member) S bears the strength burden of connecting the structures 31, 34, and the strength burden on the conductive screw member 35 is smaller than that on the male screw member (fastening male screw member) S. Thus, reliable electrical connection between the structures 31, 34 by the conductive screw member 35 is ensured. Note that, as described above, the conductive screw member 35 may have a smaller diameter than the male screw member (fastening male screw member) S, or may be made of a material having lower strength than the male screw member S.

[0057] Note that for the male screw member (fastening male screw member: a hexagonal bolt in the present embodiment) S inserted through the first through-hole H1, a washer or a spring washer is interposed between the head portion 351 and the support plate 340a. However, in the case of the conductive screw member 35, since it is necessary to bring the second peeling portion 350b into contact with the outer surface of the support plate 340a, the seating surface Sa of the head portion 351 is directly opposed to the support plate 340a without interposing a washer or a spring washer.

[0058] As described above, even if each of the swivel frame 31 and the support frame 34, which are the structures 31, 34 of the working machine 1 in the present embodiment, is painted (rust-proof treated), the swivel frame 31 and the support frame 34 can be electrically connected only by screwing (connecting) them via the conductive screw member 35. Therefore, the number of parts and the man-hours for assembly are reduced compared to the case of connecting via an earth wire.

[0059] Next, a working machine according to another embodiment of the present invention will be described. Note that, for configurations other than the configuration of the guiding screw member and the configurations associated therewith, since they are the same as those in the above embodiment, only the guiding screw member and the configurations related thereto will be described here. Also, for configurations and corresponding configurations that are the same as those in the above embodiment, the same names and the same reference numerals will be given as in the above embodiment, and for the descriptions thereof, reference will be made to the description of the first embodiment above, and the description here will be omitted.

[0060] Also in the working machine 1 of the present embodiment, two or more male screw members S and 35 for fastening the structures 31 and 34 to each other are provided, and at least one male screw member is the guiding screw member 35.

[0061] The guiding screw member 35 has a shaft portion 350 having a proximal end and a distal end in one direction, and a head portion 351 connected to the proximal end of the shaft portion 350. In the present embodiment, as shown in FIG. 8, the second through hole H2 of the other structure 34 through which the guiding screw member 35 is inserted is a stepped hole. That is, the second through hole H2 includes a large-diameter hole H2a and a small-diameter hole H2b that is smaller in diameter than the large-diameter hole H2a and through which a small-diameter portion 353 of the shaft portion 350 described later can be inserted. Also in the present embodiment, a coating film PL is formed on the inner peripheral surface of the second through hole H2 (the inner peripheral surface of the large-diameter hole H2a and the inner peripheral surface of the small-diameter hole H2b). On this premise, the guiding screw member 35 has a large-diameter portion 352 provided on the proximal end side of the shaft portion 350 and a small-diameter portion 353 provided on the distal end side of the shaft portion 350 with respect to the large-diameter portion 352 and having a smaller diameter than the large-diameter portion 352. That is, as shown in FIG. 9, the shaft portion 350 has a large-diameter portion 352 to which the head portion 351 is connected and a small-diameter portion 353 that is set to be smaller in diameter than the large-diameter portion 352 and that is continuous with the large-diameter portion 352.

[0062] The small-diameter portion 353 is configured to be threadably engaged with at least one of the overlapping two or more structures 31 and 34 that is located at least on the outermost side, and is configured to be insertable into the small-diameter hole H2b of the other structure 34 that is located at least on the outermost side. On the other hand, the large-diameter portion 352 is configured to be insertable into the large-diameter hole H2a of the other structure 34 that is located at least on the outermost side among the two or more overlapping structures 31 and 34.

[0063] In the present embodiment, the peeling structure of the conductive screw member 35 is provided on the outer peripheral surfaces of the small-diameter portion 353 and the large-diameter portion 352. The peeling structure provided on the outer periphery of the large-diameter portion 352 includes ridges 352a... and grooves 352b... having a longitudinal length in the axial direction, and the ridges 352a... and grooves 352b... are alternately arranged in the circumferential direction. That is, the peeling structure of the large-diameter portion 352 is formed in a reamer shape. Note that the ridges 352a... and grooves 352b... only need to have a longitudinal length in the axial direction of the large-diameter portion 352, and may be formed in a straight groove reamer shape arranged along the axial direction, or may be formed in a twisted groove reamer shape in which the ridges 352a... and grooves 352b... are formed in a spiral shape. The maximum diameter of the large-diameter portion 352 is set to be equal to or slightly larger than the mechanical dimension (the under-hole dimension without the coating film PL) of the hole (large-diameter hole) of the structure 34. When the small-diameter portion 353 is screwed into the second screw hole SH2 of one of the structures 31, the coating film PL on the inner peripheral surface of the large-diameter hole H2a is removed, and the tip of the ridge 352a... comes into contact with the metal substrate MB.

[0064] Incidentally, the second through-hole H2 provided in the structure 34 is a stepped hole having a large-diameter hole H2a with the same length (depth) as the axial length of the large-diameter portion 352 and a small-diameter hole H2b through which the shaft portion 350 can be inserted. When it is formed as such a stepped hole, the conductive screw member 35 may have, in addition to the convex strips 352a... and the concave strips 352b..., a protrusion protruding from an annular surface around the small-diameter portion 353, which is a connection surface between the large-diameter portion 352 and the small-diameter portion 353, as a peeling structure. Also, similar to the above-described embodiment, the conductive screw member 35 may have a protrusion protruding from the seating surface Sa as a peeling structure. In any of these aspects, as the small-diameter portion 353 is screwed with the structures 30, 31, 32, 33, 34 and advances in the axial direction, the coating film PL on the outer surface is peeled off, the metal substrate MB is exposed, and the peeling structure continuous with the large-diameter portion 352 contacts the metal substrate MB.

[0065] On the other hand, the peeling structure provided on the outer peripheral surface of the small-diameter portion 353 is a plurality of protrusions 350a... arranged at intervals in the circumferential direction, and the plurality of protrusions 350a... protruding from the thread crest. That is, the peeling structure provided on the outer peripheral surface of the small-diameter portion 353 is, similar to the above-described embodiment, protrusions 350a... protruding in a burr shape from the thread crest, and a plurality of them are arranged at intervals in the circumferential direction. Such a configuration is the same as the above-described embodiment, and by the plurality of protrusions 350a..., in the range X screwed into the second screw hole SH2, the coating film PL on the inner peripheral surface of the second screw hole SH2 is removed.

[0066] Also, if the large-diameter portion 352 is formed to straddle two or more members of the structure and the small-diameter portion 353 is screwed into the outermost structure 31, it becomes possible to fasten and electrically connect three or more structures.

[0067] The above-described embodiment (a preferred embodiment of the present invention) is as described above. The above-described embodiment includes a number of inventions including the present invention, and in particular, provides the inventions described in the following items.

[0068] (Item 1) The working machine 1 includes an electrical component EP, at least two structures 30, 31, 32, 33, 34 each having conductivity, and a conductive screw member 35 that connects the at least two structures 30, 31, 32, 33, 34 to be electrically conductive.

[0069] According to the working machine 1 of item 1, there is no need for a ground wire or a screw member for fixing the ground wire, the number of parts can be reduced, and as a result, the man-hours for electrically connecting the structures 30, 31, 32, 33, 34 to each other can be reduced. Also, there is no need to secure a space for routing the ground wire, and problems such as disconnection of the ground wire are eliminated.

[0070] (Item 2) At least one of the structures 31, 34 that are conductively connected by the conductive screw member 35 includes a conductive metal substrate MB and a coating film PL formed on the metal substrate MB. The conductive screw member 35 has peeling structures 350a, 350b that peel the coating film PL at the contact portion with the structures 31, 34 and bring the conductive screw member 35 into contact with the metal substrate MB. The working machine 1 according to item 1.

[0071] According to the working machine 1 of item 2, a coating film PL (insulating layer) exists on the surface layer of the structures 31, 34 Even in this case, the conductive screw member 35 can be brought into contact with the metal substrate MB of the structures 31, 34 to connect the structures 31, 34 to be electrically conductive.

[0072] (Item 3) At least one of the structures 31, 34 that are conductively connected by the conductive screw member 35 includes a conductive metal substrate MB and a coating film PL formed on the metal substrate MB. The conductive screw member 35 has a contact portion that penetrates the coating film PL and contacts the metal substrate MB at the contact portion with the structures 31, 34. The working machine 1 according to item 1.

[0073] According to the working machine 1 of item 3, even when a coating film PL (insulating layer) exists on the surface layers of the structures 31 and 34, the conductive screw member 35 can be brought into contact with the metal substrate MB of the structures 31 and 34, and the structures 31 and 34 can be conductively (electrically) connected to each other.

[0074] (Item 4) The conductive screw member 35 includes a shaft portion 350 having a thread screwed into at least one of two or more overlapping structures 31 and 34, and, as a peeling structure, a protrusion 350a protruding radially outward from the thread to the shaft portion. The working machine 1 according to item 2.

[0075] According to the working machine 1 of item 4, by simply screwing the conductive screw member 35 into the structure 31, the structures 31 and 34 can be conductively (electrically) connected to each other.

[0076] (Item 5) The conductive screw member 35 includes a head portion 350 provided at the base end portion of the shaft portion 350 and having a seating surface Sa that contacts one of the structures 34, and, as a peeling structure, a convex portion 350a protruding from the seating surface Sa. The working machine 1 according to item 4.

[0077] According to the working machine 1 of item 5, by rotating (tightening) the male screw member S around the shaft portion 350, the coating film PL in the region facing the seating surface Sa is peeled off, and the seating surface Sa (the convex portion 350b protruding from the seating surface Sa) can be conductively (electrically) connected to the structure 34.

[0078] (Item 6) The conductive screw member 35 has a large-diameter portion 352 provided on the base end side of the shaft portion 350, and a small-diameter portion 353 provided on the tip end side of the shaft portion 350 with respect to the large-diameter portion 352 and having a smaller diameter than the large-diameter portion 352. The small-diameter portion 353 has a thread that is screwed into at least one of the overlapping two or more structures 31 and 34 located on the tip end side of the shaft portion 350. The large-diameter portion 352 is configured to be insertable into a large-diameter hole H2a provided in the structure 34 located on the most base end side of the shaft portion 350 among the two or more overlapping structures 31 and 34. As a peeling structure, a protrusion 350a protruding radially outward of the shaft portion 350 from the thread is provided on the outer peripheral surface of the small-diameter portion 353, and the working machine 1 according to item 4.

[0079] According to the working machine 1 of item 6, the coating film PL in the region facing the small-diameter portion 353 can be peeled or removed, and the small-diameter portion 353 can be conductively (electrically) connected to the opposing structure 31.

[0080] (Item 7) On the outer periphery of the large-diameter portion 353, as a peeling structure, there are convex ridges 352a... and concave ridges 352b... having a longitudinal length in the axial direction of the shaft portion 350, and the convex ridges 352a... and the concave ridges 352b... are alternately arranged in the circumferential direction, and the working machine 1 according to item 6.

[0081] According to the working machine 1 of item 7, the coating film PL on the inner peripheral surface of the large-diameter hole H2a of the other structure 34 can be scraped off and peeled by the convex ridges 352a, and the convex ridges 352a... can be brought into contact or pressure contact with the metal substrate (metal) MB of the structure 34.

[0082] (Item 8) As structures, it has a traveling frame 30, a slewing frame 31 that is pivotally connected around an axis extending in the vertical direction with respect to the traveling frame 30, and a support frame 34 that is connected to the slewing frame 31 and supports other members, and the slewing frame 31 and the support frame 34 are electrically connected by a conductive screw member 35, and the working machine 1 according to any one of items 1 to 7.

[0083] According to the working machine 1 of Item 8, the slewing frame 31 and the support frame 34 are electrically connected by the conductive screw member 35 to be at the same electric potential.

[0084] (Item 9) The slewing frame 31 includes a fixing portion 314... for fixing the support frame 34 to the slewing frame 31 in a state where the support frame 34 is superposed on the slewing frame 31 with two or more male screw members S, 35, and among the two or more male screw members S, 35, at least one is the conductive screw member 35. The working machine 1 according to Item 8.

[0085] According to the working machine 1 of Item 9, the support frame 34 can be conductively (electrically) connected to the fixing portion 314... of the slewing frame 31. Thereby, the slewing frame 31 (fixing portion 314...) and the support frame 34 can be made to be at the same electric potential.

[0086] (Item 10) Separate from the conductive screw member 35, two or more fastening male screw members S, S for fixing the support frame 34 to the fixing portion 314 are provided, and the conductive screw member 35 connects the fixing portion 314 and the support frame 34 between the two or more fastening male screw members S, S. The working machine 1 according to Item 9.

[0087] According to the working machine 1 of Item 10, the male screw members S, S on both sides of the conductive screw member 35 can be given a strength burden.

[0088] (Item 11) The conductive screw member 35 has a smaller diameter than the fastening screw member S. The working machine 1 according to Item 10.

[0089] According to the working machine 1 of Item 11, while suppressing the occupied space of the conductive screw member 35, the fixing portion 314 and the support frame 34 can be conductively connected.

[0090] Note that the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist of the present invention.

[0091] In the above-described embodiment, the cabin is adopted for the driver's seat protection mechanism 32, but the present invention is not limited thereto. For example, the driver's seat protection mechanism 32 may be a so-called canopy having a roof that covers the head of the operator sitting on the driver's seat DS and a support column 313 that supports the roof. Further, the work machine 1 may be configured not to include the driver's seat protection mechanism 32. Further, the work machine 1 may be a remotely operated or autonomously driven work machine that does not include the driver's seat DS.

[0092] In the above-described embodiment, the battery 5 includes the battery 5a that supplies power to the electrical components EP and the drive battery 5b that supplies power to the electric motor, but the present invention is not limited thereto. For example, the work machine 1 may include a single large battery (battery pack) that supplies power to both the electrical components EP and the electric motor of the prime mover 6 as the battery 5.

[0093] In the above-described embodiment, an electric motor is adopted for the prime mover 6, but the present invention is not limited thereto. For example, the prime mover 6 may be an internal combustion engine such as a diesel engine, a gasoline engine, an LPG engine, or a hydrogen engine. Further, the prime mover 6 may be of a hybrid type that combines an internal combustion engine and an electric motor. As described above, when an internal combustion engine is adopted for the prime mover 6, it goes without saying that the work machine 1 includes only the battery 5b that supplies power to the electrical components EP as the battery 5. Further, when the prime mover 6 is of a hybrid type that combines an internal combustion engine and an electric motor, similar to the above-described embodiment, the work machine 1 may include the battery 5a that supplies power to the electrical components EP and the drive battery 5b that supplies power to the electric motor as the battery 5, or may include a single large battery (battery pack) that supplies power to both the electrical components EP and the electric motor of the prime mover 6.

[0094] ​In the above embodiment, the swivel frame 31 and the support frame 34 are connected and fastened by the conductive screw member 35 so as to be electrically conductive. However, the connection by the conductive screw member 35 is not limited to the connection between the swivel frame 31 and the support frame 34. For example, the connection by the conductive screw member 35 may be the connection between the driver's seat protection mechanism 32 and the swivel frame 31, or the connection between the traveling frame 30 and the swivel frame 31 (fixing to the slewing bearing BR). That is, the connection by the conductive screw member 35, which is a conductive member, is applicable to the connection between the structures 30, 31, 32, 33, 34 to which the electrical components EP are attached, the structures 30, 31, 32, 33, 34 including the metal substrate MB and the coating film PL, and another structure 30, 31, 32, 33, 34 connected to the structures 30, 31, 32, 33, 34, the other structure 30, 31, 32, 33, 34 including the metal substrate MB and the coating film PL. Further, in this embodiment, the bonnet 33 made of a metal material is used, but the present invention is not limited thereto. For example, a bonnet 33 made of a non-conductive resin material may be used.

[0095] In the above embodiment, the backhoe has been described as an example, but the working machine 1 is not limited to the backhoe. For example, the working machine 1 may be an agricultural machine such as a combine harvester, a rice transplanter, or a lawn mower, a construction machine such as a wheel loader, a compact track loader, or a skid steer loader, or an industrial machine such as a forklift.

Explanation of Reference Numerals

[0096] 1: Working machine 3: Machine body 30: Traveling frame (structure) 31: Swivel frame (structure) 32: Driver's seat protection mechanism (cab: structure) 33: Bonnet (structure) 34: Support frame (structure) 35: Conductive screw member 35: Male screw member 314: Fixed part 350: Shaft part 350a: First peeling part (peeling structure) 350b: Second peeling part (peeling structure) 351: Head 352: Large-diameter part 352a: Rib 352b: Groove 353: Small-diameter part CL: Axis Ca: Surface EP: Electrical component H2a: Large-diameter hole MB: Metal substrate (metal material) PL: Coating film S: Male screw member Sa: Seat surface

Claims

1. An operating machine comprising: an electrical component; at least two structures each having conductivity; and a conductive screw member for connecting the at least two structures in a conductive manner.

2. At least one of the structures conductively connected by the conductive screw member includes a conductive metal substrate and a coating film formed on the metal substrate, and the conductive screw member has a peeling structure for peeling the coating film at a contact portion with the structure and bringing the conductive screw member into contact with the metal substrate. The operating machine according to Claim 1.

3. At least one of the structures conductively connected by the conductive screw member includes a conductive metal substrate and a coating film formed on the metal substrate, and the conductive screw member has a contact portion that penetrates the coating film and contacts the metal substrate at a contact portion with the structure. The operating machine according to Claim 1.

4. The conductive screw member includes a shaft portion having a thread screwed onto at least one of two or more overlapping structures, and as the peeling structure, a protrusion protruding radially outward from the shaft portion from the thread. The operating machine according to Claim 2.

5. The conductive screw member includes a head portion provided at a base end portion of the shaft portion and having a seating surface that contacts one of the structures, and as the peeling structure, a convex portion protruding from the seating surface. The operating machine according to Claim 4.

6. The conductive screw member has a large-diameter portion provided on the base end side of the shaft portion and a small-diameter portion provided on the tip side of the shaft portion relative to the large-diameter portion and having a smaller diameter than the large-diameter portion. The small-diameter portion has a thread screwed onto at least one of two or more overlapping structures located on the tip side of the shaft portion, and the large-diameter portion is configured to be insertable into a large-diameter hole provided in the structure located on the most base end side of the two or more overlapping structures. As the peeling structure, a protrusion protruding radially outward from the shaft portion from the thread is provided on an outer peripheral surface of the small-diameter portion. The operating machine according to Claim 4.

7. On an outer periphery of the large-diameter portion, as the peeling structure, there are provided a convex stripe and a concave stripe having a length in the axial direction of the shaft portion and alternately arranged in the circumferential direction. The operating machine according to Claim 6.

8. As the structure, it has a traveling frame, a slewing frame that is rotatably connected around an axis extending in the vertical direction with respect to the traveling frame, and a support frame that is connected to the slewing frame and supports other members. The work machine according to any one of claims 1 to 7, wherein the slewing frame and the support frame are electrically connected by the electrical connection screw member.

9. The slewing frame includes a fixing portion that fixes the support frame to the slewing frame in a state where the support frame is overlapped with the slewing frame by two or more male screw members, and at least one of the two or more male screw members is the electrical connection screw member. The work machine according to claim 8.

10. Separate from the electrical connection screw member, it is provided with two or more fastening male screw members for fixing the support frame to the fixing portion. The electrical connection screw member connects the fixing portion and the support frame between the two or more fastening male screw members. The work machine according to claim 9.

11. The electrical connection screw member has a smaller diameter than the fastening screw member. The work machine according to claim 10.

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