Work machine
Patent Information
- Application Number
- JP2025544192
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Priority Date
- 2023-09-04
- Filing Date
- 2024-08-05
- Publication Date
- 2025-03-13
Abstract
Description
Work equipment
[0001] This application claims priority from Japanese Patent Application No. 2023-142855, filed September 4, 2023, and incorporates the entire contents of said Japanese application by reference.
[0002] Patent Document 1 discloses a backhoe as a work machine. The backhoe has, as its work device, an arm device extending from the machine body and a bucket attached to the tip of the arm device. The arm device has a boom (first arm) located on the machine body side and an arm (second arm) to which the bucket is attached. The boom, arm, and bucket are operated hydraulically. To this end, the machine body has a hydraulic unit, and the arm device has multiple hydraulic cylinders. The hydraulic unit and each hydraulic cylinder are connected by hydraulic piping. The hydraulic piping includes flexible hoses.
[0003] JP 2015-10386 A
[0004] A work machine according to one aspect of the present disclosure includes a body and an arm device, wherein the arm device includes a first arm, a second arm that swings around a central axis relative to the first arm, an angle detector for detecting the angle between the first arm and the second arm, a protective part that protects the angle detector, and a hose provided at a connection between the first arm and the second arm, wherein the angle detector includes a detection body provided on the first arm side, and a lever that is connected to the detection body and a member on the second arm side and displaces in accordance with the relative swing between the first arm and the second arm, wherein the protective part includes a cover that covers a displacement area of the lever, and a guide that covers the detection body and has a contour shape that is smaller than the cover when viewed from a direction along the central axis and is positioned so as to overlap the cover when viewed from a direction along the central axis, and wherein a passing area through which the hose passes is provided between the first arm or the second arm and the cover and outside the guide.
[0005] FIG. 1 is a perspective view showing an example of a work machine. FIG. 2 is a perspective view of an arm device. FIG. 3 is an explanatory diagram showing the connection between the boom and the arm and the surrounding area. FIG. 4 is an explanatory diagram of the tip of the boom. FIG. 5 is a perspective view of the tip of the boom shown in FIG. 4. FIG. 6 is a perspective view showing the connection between the boom and the arm and the surrounding area. FIG. 7 is an image diagram showing the tip of the boom excluding the outer wall of the cover. FIG. 8 is a perspective view of the cover and guide. FIG. 9 is an explanatory diagram showing a modified example of the protective section.
[0006] <Problem to be Solved by the Invention of the Present Disclosure> The arm is attached to the tip of the boom and is capable of swinging relative to the boom. The arm device has an angle detector (potentiometer) for detecting the angle between the boom and the arm. Hydraulic piping is provided along the boom and the arm, and the hose is provided so as to straddle the connection (joint) between the boom and the arm. When the arm swings relative to the boom, the hose may slacken and come close to the angle detector or the like provided at the connection. The hose is arranged so as to curve in a large circle around the connection so as not to interfere with the angle detector, and its position is restricted to the boom and arm by a clamp.
[0007] Therefore, depending on the angle of the arm, the hose may protrude significantly, or multiple clamps may be required to regulate the position of the hose, making the configuration complicated. Therefore, the present disclosure aims to provide a work machine in which the hose is positioned more smartly than before.
[0008] <Effects of the Invention of the Present Disclosure> According to the work machine of the present disclosure, the hose is arranged more smartly than before.
[0009] <Outline of Embodiments of the Invention of the Present Disclosure> Below, outlines of embodiments of the invention of the present disclosure will be listed and described. (1) An embodiment of a work machine includes a body and an arm device, wherein the arm device includes a first arm, a second arm that swings around a central axis relative to the first arm, an angle detector for detecting the angle between the first arm and the second arm, a protective part that protects the angle detector, and a hose provided at a connection between the first arm and the second arm, wherein the angle detector includes a detection body provided on the first arm side, and a lever that is connected to the detection body and a member on the second arm side and displaces in accordance with the relative swing between the first arm and the second arm, wherein the protective part includes a cover that covers a displacement area of the lever, and a guide that covers the detection body and has a contour shape that is smaller than the cover when viewed in a direction along the central axis and is positioned so as to overlap the cover when viewed in a direction along the central axis, and wherein a passing area through which the hose passes is provided between the first arm or the second arm and the cover and outside the guide.
[0010] With a work machine having the above configuration, the hose can be positioned with a small turning radius around the detection body side of the angle detector. Because a guide is interposed between the hose and the detection body, the hose does not interfere with the detection body. The portion of the hose that curves around the detection body side and passes through the passage area is hidden by a cover. The hose is positioned more smartly than before.
[0011] (2) Preferably, the guide has an outer circumferential surface whose contour shape when viewed from a direction along the central axis is a shape that follows a circular arc, and the passing area is provided along the outer circumferential surface. According to the above configuration, the guide having the outer circumferential surface that follows a circular arc is located inside the hose that curves around the detection body.
[0012] (3) Preferably, in the work machine of (1) or (2), the first arm has an arc-shaped end face at a tip end where the angle detector is provided, the end face and the guide are positioned side by side in a direction parallel to the central axis, and the passing area is provided between the second arm and the cover in an area outside the guide and the end face. In this configuration, the end face of the tip end of the first arm and the guide are positioned between the second arm and the cover. The hose passes outside one or both of the end face and the guide.
[0013] (4) Preferably, in the work machine of any one of (1) to (3), the guide is integral with the cover, and the guide and the cover are detachable from the first arm. This configuration makes it easy to attach the cover and the guide to the first arm, and also makes it easy to replace the cover and the guide.
[0014] (5) Preferably, the work machine of (4) has a bracket for attaching the detection body to the first arm, the detection body being positioned inside an outer edge of the bracket when viewed from the direction along the central axis, and the inner peripheral surface of the guide facing the outer peripheral surface of the bracket. According to this configuration, even if a large force acts on one or both of the cover and the guide, or if one or both of the cover and the guide are deformed by that force, the guide abuts against the bracket and does not come into contact with the angle detector, making it difficult for the angle detector to be affected.
[0015] (6) Preferably, in any one of the work machines (1) to (3), the first arm has a bracket to which the detection body is attached, the guide is integral with the bracket, and the cover is separate from the guide and the bracket. In this configuration, the detection body is attached to the bracket, and the bracket and guide are integrated. Even if a large force acts on the cover or the cover is deformed by that force, the cover is separate from the guide and bracket, so that the effect is unlikely to be felt by the detection body.
[0016] (7) Preferably, in the work machine of any one of (1) to (5), the cover and the guide are attached to the first arm without contacting the angle detector. With this configuration, even if a large force acts on one or both of the cover and the guide, or if one or both of the cover and the guide are deformed by the force, the effect of the force is unlikely to be felt on the angle detector.
[0017] (8) Preferably, in any one of the work machines (1) to (6), the cover has an outer peripheral wall that covers the outside of the displacement area of the lever, an outer wall that is connected to the outer peripheral wall and covers the angle detector from the outside in the width direction of the machine body, and an inner wall that is connected to the outer peripheral wall and is positioned inward in the width direction of the machine body relative to the outer wall and faces the outer wall, and the inner wall is located outward in the width direction of the machine body of the hose passing through the passing area. According to this configuration, the outer wall covers and protects the angle detector from the outside in the width direction of the machine body. The outer peripheral wall covers and protects the angle detector from its outer periphery. The inner wall serves as a restricting member that prevents the hose passing through the passing area from being displaced outward in the width direction of the machine body.
[0018] (9) Preferably, in the work machine of (8), the outer wall is provided over substantially the entire circumferential area of the outer wall around the detection body, and the inner wall is provided corresponding to a portion of the outer wall around the detection body, and the displacement area of the lever is included in the area of the cover where the inner wall is not provided. According to this configuration, the outer wall widely covers and protects the angle detector having the detection body. The inner wall acts as a restricting member that prevents the hose passing through the passage area from being displaced outward in the width direction of the machine body, and the inner wall does not interfere with the lever that is displaced by the swinging of the first arm and the second arm.
[0019] (10) In the work machine of (9), preferably, the length of the guide in a circumferential direction about the detection body is longer than the length of the inner wall in the circumferential direction. In this case, the guide is provided over as wide an area as possible between the hose and the detection body.
[0020] (11) Preferably, in the work machine of any one of (1) to (9), the cover has an arc-shaped outer peripheral wall that covers the outside of the displacement area of the lever that is formed in an arc shape around the central axis. According to the configuration, the cover has a shape suitable for a member that covers the displacement area of the lever that is formed in an arc shape from the outside.
[0021] <Details of the embodiments of the present disclosure> Hereinafter, the details of the embodiments of the present disclosure will be described with reference to the drawings. Note that at least some of the embodiments described below may be combined in any manner.
[0022] [Overall configuration of work machine] Figure 1 is a perspective view showing an example of a work machine 10. The work machine 10 shown in Figure 1 is a swivel work machine, and is called a backhoe. The work machine 10 has a machine body (swivel base) 11, a traveling device 12, and a work device. The work device is an arm device 13. The arm device 13 has a boom 31 which is a first arm, and an arm 32 which is a second arm. Note that the work machine is not limited to a backhoe as long as it has the machine body 11 and the arm device 13 which is integrated with the machine body 11.
[0023] The directions of the work machine 10 are defined below. The direction in which a driver seated correctly in the driver's seat 22 of the work machine 10 faces is defined as "forward," and the opposite direction is defined as "rearward." When the driver is facing forward, the left side is defined as "left," and the right side is defined as "right." The front-to-rear direction and the left-to-right direction are perpendicular to each other. In the following description, the left-to-right direction is also referred to as the "machine body width direction." The direction perpendicular to both the front-to-rear direction and the machine body width direction is defined as the up-to-down direction. The up-to-down direction is also referred to as the height direction.
[0024] In each figure, orthogonal three-dimensional coordinates are shown, with the forward direction indicated by arrow X1 and the backward direction indicated by arrow X2. The left direction is indicated by arrow Y1 and the right direction is indicated by arrow Y2. The up direction is indicated by arrow Z1 and the down direction is indicated by arrow Z2. The direction from the center of the machine body width direction to the right or left is sometimes referred to as the "outward direction in the machine body width direction." The outward direction in the machine body width direction is the direction away from the center of the machine body width direction of the work machine 10. The direction opposite to the outward direction in the machine body width direction is sometimes referred to as the inward direction in the machine body width direction. The inward direction in the machine body width direction is the direction approaching the center of the work machine 10 in the machine body width direction.
[0025] The arm device 13 swings (swings) around a central axis in the vertical direction (i.e., left and right) relative to the machine body 11. When describing each part of the arm device 13, it is assumed that the arm device 13 does not swing left and right, but is in a state facing straight ahead as shown in FIG.
[0026] The machine body 11 has a revolving frame 21 that serves as a framework, and a driver's seat 22 that is mounted on the revolving frame 21 and in which a driver sits. In the case of the work machine 10 shown in Fig. 1 , the machine body 11 has a cabin 23 that surrounds the driver's seat 22. The machine body 11 may have a canopy instead of the cabin 23.
[0027] The work machine 10 has a swivel bearing 14. The machine body 11 (swivel frame 21) is supported by the traveling device 12 via the swivel bearing 14. The swivel bearing 14 allows the machine body 11 to swivel about a central axis in the vertical direction. The machine body 11 (swivel frame 21) swivels hydraulically or electrically.
[0028] The machine body 11 has a prime mover 24 mounted on the revolving frame 21, and a hydraulic device (hydraulic unit) 25. The prime mover 24 is a diesel engine. The prime mover 24 may be a gasoline engine or an electric motor, or may be a hybrid type having an engine and an electric motor. Although not shown, the hydraulic device 25 has a tank that stores hydraulic oil, a hydraulic pump, and a hydraulic circuit. The hydraulic device 25 generates hydraulic pressure to operate hydraulic actuators.
[0029] The traveling device 12 supports the machine body 11 so that it can travel. The traveling device 12 shown in FIG. 1 is a crawler-type device. The traveling device 12 has a traveling frame 29, a first traveling device 28L provided on the left side of the traveling frame 29, and a second traveling device 28R provided on the right side of the traveling frame 29. The first traveling device 28L and the second traveling device 28R are driven by a traveling motor (not shown) configured with a hydraulic motor (hydraulic actuator). Note that the traveling device 12 is not limited to a crawler-type, and may be a wheel-type.
[0030] 1 has a dozer device 27 located in front thereof. The dozer device 27 is driven by a hydraulic cylinder (hydraulic actuator) (not shown). The dozer device 27 may be omitted.
[0031] The machine body 11 has a support bracket 15 and a swing bracket 16 at its front. The support bracket 15 is provided to protrude forward from the machine body 11 (swivel frame 21). The swing bracket 16 is attached to the front of the support bracket 15 so as to be swingable around a central axis in the up-down direction. The swing bracket 16 swings due to the extension and contraction of a swing cylinder (not shown) provided between the swing bracket 16 and the machine body 11.
[0032] The arm device 13 is attached to the swing bracket 16. The arm device 13 has a boom 31, an arm 32, and a bucket 33. Figure 2 is a perspective view of the arm device 13. The boom 31 is attached to the swing bracket 16 at its base 41. The boom 31 is supported by the swing bracket 16 and is swingable about a central axis C0 in the width direction of the machine body. A boom cylinder 34 is provided between the swing bracket 16 and the boom 31. The boom 31 swings relative to the swing bracket 16 due to the extension and contraction of the boom cylinder 34.
[0033] The arm 32 is attached at its base 51 to the tip 43 of the boom 31. The arm 32 is supported by the boom 31 and is swingable about a central axis C1 in the width direction of the machine body. An arm cylinder 35 is provided between the boom 31 and the arm 32. The arm 32 swings relative to the boom 31 as the arm cylinder 35 extends and retracts.
[0034] The bucket 33 is attached to the tip 53 of the arm 32. The bucket 33 is supported by the arm 32 and is swingable about a central axis C2 in the width direction of the machine body. The bucket 33 is capable of scooping and dumping operations. The scooping operation is an operation in which the bucket 33 is swung in a direction toward the boom 31, for example, an operation for scooping up earth and sand. The dumping operation is an operation in which the bucket 33 is swung in a direction away from the boom 31, for example, an operation for dropping (discharging) scooped earth and sand. A bucket cylinder 36 is provided between the arm 32 and the bucket 33. The bucket 33 swings relative to the arm 32 as the bucket cylinder 36 extends and retracts.
[0035] The boom cylinder 34, arm cylinder 35, bucket cylinder 36, and the swing cylinder (not shown) are composed of hydraulic cylinders (hydraulic actuators). These hydraulic cylinders are operated by hydraulic pressure generated by a hydraulic device 25 (see FIG. 1) mounted on the machine body 11. To supply hydraulic oil from the hydraulic device 25 to each hydraulic cylinder, the arm device 13 has multiple hydraulic pipes 85 provided along the boom 31 and arm 32.
[0036] The hydraulic piping 85 includes a pipe 81 and a hose 80. The pipe 81 is made of, for example, metal, and is fixed to the boom 31 and the arm 32 by clamps 82. The hose 80 is flexible. The hose 80 is connected to the pipe 81 via a joint. The hose 80 (see FIG. 2 ) is provided across the connection portion 37 between the boom 31 and the arm 32. The hose 80 is part of the hydraulic piping 85 for supplying hydraulic oil to a service port SP to which various hydraulic actuators are connected. Note that the hose 80 may also supply hydraulic oil to the bucket cylinder 36 or the arm cylinder 35.
[0037] The arm device 13 can be fitted with another working tool (attachment) that can be driven by a hydraulic actuator instead of or in addition to the bucket 33. Examples of other working tools include a hydraulic breaker, a hydraulic crusher, an angle broom, an earth auger, a pallet fork, a sweeper, a mower, and a snow blower.
[0038] [Configuration of Each Part of Arm Device 13] As described above, the arm device 13 has the boom 31 and the arm 32 that swings relative to the boom 31. The boom 31 has a base 41, a boom main body 42, and a tip 43. The base 41 is made of, for example, cast steel. The boom main body 42 has a structure in which, for example, a plurality of steel plates are assembled by welding, and in this embodiment, has a shape that is bent at the middle. The tip 43 is made of, for example, cast steel. The base 41 and the tip 43 are fixed to the boom main body 42 by welding.
[0039] The arm 32 has a base 51, an arm body 52, and a tip 53. The arm 32 has a structure in which a plurality of steel plates are assembled by welding, and in this embodiment, has a linear shape.
[0040] Figure 3 is an explanatory diagram showing the connection portion 37 between the boom 31 and the arm 32 and its surroundings. Figure 4 is an explanatory diagram of the tip 43 of the boom 31. Figure 4 shows a state in which the arm 32 has been detached from the tip 43. The arm device 13 has an angle detector 60 for detecting the angle formed by the boom 31 and the arm 32, and a protector 70 for protecting the angle detector 60. Figures 3 and 4 show a state in which the protector 70 has been detached in order to explain the angle detector 60.
[0041] The tip 43 of the boom 31 (see FIG. 4 ) has a tip main body 430, a first frame 431, a second frame 432, and a pin 433. The tip 43 has a bifurcated shape that branches into two from the tip main body 430, one of the bifurcated portions being the first frame 431 and the other being the second frame 432. The pin 433 is attached to the first frame 431 and the second frame 432. The base 51 of the arm 32 is attached to the pin 433, and the arm 32 is swingable around a central axis C1 of the pin 433. The central axis C1 is the swing center line of the boom 31 and the arm 32.
[0042] The angle detector 60 is a rotary potentiometer and includes a detection body 61 and a lever 62. The detection body 61 includes a cylindrical case 611 and a sensor 612 configured with a variable resistor and the like provided inside the case 611. The sensor 612 has a rotation shaft (not shown), to which one end 621 of the lever 62 is attached. The central axis of the rotation shaft coincides with an extension of the central axis C1 of the pin 433. The sensor 612 detects the displacement (rotation) of the lever 62.
[0043] The detection body 61 is provided at the tip 43 of the boom 31. In the present embodiment, the boom 31 has a bracket 55, and the bracket 55 attaches the detection body 61 to the boom 31. The bracket 55 is plate-shaped and is fixed to the tip 43 by a bolt 78. The detection body 61 is attached to the first frame 431 via the bracket 55.
[0044] One end 621 of the lever 62 is connected to the detection body 61 (the rotation axis of the sensor 612), and the other end 622 of the lever 62 is connected to the mounting member 56 provided on the arm 32 (see FIG. 3 ). The lever 62 is displaced about the central axis C1 in accordance with the relative swing of the boom 31 and the arm 32. The angle detector 60 detects the displacement angle of the lever 62 as the swing angle of the boom 31 and the arm 32.
[0045] [Protection Unit 70] Figure 5 is a perspective view of the tip 43 of the boom 31 shown in Figure 4 when viewed from the opposite side in the width direction of the machine body. The protection unit 70 has a cover 71 and a guide 72 to protect the angle detector 60 (see Figures 4, 5, and 8). Figure 8 is a perspective view of the cover 71 and the guide 72. The cover 71 and the guide 72 are made of metal and are formed by assembling thin plates. In this embodiment, the cover 71 has an outer peripheral wall 711, an outer wall 712 connected to the outer peripheral wall 711, and an inner wall 713 connected to the outer peripheral wall 711. The outer peripheral wall 711 covers the area (displacement area K2) where the lever 62 is displaced by the relative swing of the boom 31 and the arm 32. The outer peripheral wall 711 has an outer peripheral surface shaped along an arc. In other words, the outer peripheral wall 711 is an arc-shaped wall. The outer peripheral wall 711 covers the outside of the displacement region K2 of the lever 62, which is formed in an arc shape around the central axis C1. The outer wall 712 covers the angle detector 60 from the outside in the width direction of the machine body. In other words, the outer wall 712 covers the angle detector 60 from the side opposite the tip 43 (first frame 431) of the boom 31 in the width direction of the machine body.
[0046] The inner wall 713 is disposed inward in the width direction of the machine body than the outer wall 712. The inner wall 713 is connected to the outer wall 712 via the outer peripheral wall 711 and faces the outer wall 712. The guide 72 is disposed in a position overlapping (overlapping) the cover 71 when viewed from the direction along the central axis C1. The outline shape of the guide 72 when viewed from the direction along the central axis C1 is smaller than that of the cover 71. More specifically, the guide 72 has an outline shape smaller than that of the outer peripheral wall 711. In this embodiment, the guide 72 has a smaller diameter than the outer peripheral wall 711 and an outer peripheral surface 72a whose outline shape when viewed from the direction along the central axis C1 is an arc shape. The guide 72 covers the detection main body 61. The outer peripheral wall 711 and the guide 72 form the protective part 70 in a two-stage shape with varying outer peripheral outline shapes.
[0047] 6 is a perspective view showing the connection portion 37 between the boom 31 and the arm 32 and its surroundings. Between the base 51 of the arm 32 and the cover 71, and outside (on the outer periphery of) the guide 72, is a passage area K1 through which the hose 80 passes. The passage area K1 is an arc-shaped space centered on the detection main body 61. An inner wall 713 (see FIG. 5) is located outward in the machine body width direction of the hose 80 passing through the passage area K1. The space between the inner wall 713 and the base 51 of the arm 32 is the passage area K1.
[0048] As described above, the outer wall 712 (see FIG. 4) covers and protects the angle detector 60, including the lever 62, from the outside in the width direction of the aircraft. The outer peripheral wall 711 (see FIG. 5) covers and protects the angle detector 60, including part of the lever 62, from its outer periphery. The inner wall 713 serves as a restricting member that prevents the hose 80 passing through the passage area K1 from being displaced outward in the width direction of the aircraft.
[0049] The guide 72 serves as a backing plate with which the hose 80 can come into contact, and covers and protects the detection main body 61. The guide 72 has an arc-shaped configuration, and is positioned on the inside of the hose 80 that curves at the connection portion 37 between the boom 31 and the arm 32. The guide 72 has a shape suitable for a member that is positioned on the inside of the curved hose 80.
[0050] As described above (see FIGS. 4 and 5 ), the tip portion 43 of the boom 31, on which the angle detector 60 is provided, has the first frame 431. The first frame 431 has an arc-shaped end surface (boom end surface 44) at its tip. That is, the boom 31 has the arc-shaped boom end surface 44 at the tip portion 43. The boom end surface 44 and the guide 72 are positioned side by side in a direction parallel to the central axis C1 of the swing of the boom 31 and the arm 32 (see FIG. 7 ). FIG. 7 is an image diagram showing the tip portion 43 of the boom 31 without the outer wall 712 of the cover 71. In this embodiment, the radius of the arc-shaped boom end surface 44 and the radius of the arc-shaped outer peripheral surface 72a of the guide 72 are the same (or substantially the same).
[0051] With this configuration, the guide 72 and the boom end surface 44 are located between the base 51 of the arm 32 and the cover 71. Therefore, the passing area K1 for the hose 80 is provided between the base 51 of the arm 32 and the cover 71, in an area outside (on the outer periphery of) the guide 72 and the boom end surface 44. The hose 80 can pass outside one or both of the guide 72 and the boom end surface 44.
[0052] Although not shown, the radius of the boom end surface 44 may be larger than the radius of the guide 72. For example, although not shown, the radius of the boom end surface 44 may be the same as (approximately the same as) the radius of the outer peripheral wall 711. In this case, the area between the tip 43 (first frame 431) of the boom 31 and the cover 71 and the outside (outer peripheral side) of the guide 72 becomes the passing area K1 for the hose 80. In other words, it is sufficient that the area between the tip 43 of the boom 31 or the base 51 of the arm 32 and the cover 71 and the outside (outer peripheral side) of the guide 72 becomes the passing area K1 for the hose 80.
[0053] The cover 71 (see FIG. 7 ) has an auxiliary wall 714 on the opposite side of the outer peripheral wall 711, with the detection body 61 at the center. The auxiliary wall 714 is connected to both ends of the outer peripheral wall 711. The detection body 61 is widely covered and protected by the outer peripheral wall 711 and the auxiliary wall 714. The space surrounded by the outer peripheral wall 711 and the auxiliary wall 714 is closed by the outer wall 712 (see FIG. 4 ). As shown in FIG. 7 , the auxiliary wall 714 has an opening 714 a through which a signal line 79 connected to the sensor 612 of the detection body 61 passes. There is a possibility that the signal line 79 may come into contact with the opening 714 a. For this reason (see FIG. 8 ), a round bar 714 b is provided at the edge of the opening 714 a as an edge guard, and the opening 714 a has a convex curved shape.
[0054] The outer wall 712 (see FIG. 4 ) is provided over substantially the entire area (along substantially the entire circumference) of the outer peripheral wall 711 in the circumferential direction centered on the detection body 61. The outer wall 712 widely covers and protects the angle detector 60 having the detection body 61. In contrast, the inner wall 713 (see FIG. 7 ) is provided corresponding to (along) a portion Q of the outer peripheral wall 711 in the circumferential direction centered on the detection body 61. A displacement region K2 of the lever 62 is included in the range of the cover 71 where the inner wall 713 is not provided.
[0055] As described above, the inner wall 713 serves as a restricting member that prevents the hose 80 (see FIG. 5 ) passing through the passage area K1 from being displaced outward in the width direction of the machine body, and by being provided in a portion Q along the circumferential direction, the inner wall 713 does not interfere with the lever 62, which is displaced by the swinging of the boom 31 and the arm 32. The length of the guide 72 in the circumferential direction about the detection main body 61 is longer than the length of the inner wall 713 in the circumferential direction. In other words, the guide 72 is provided along the circumferential direction about the detection main body 61 on the outer circumferential wall 711 over an area wider than the portion Q where the inner wall 713 is provided. The guide 72 is provided over as wide an area as possible between the hose 80 and the detection main body 61.
[0056] The protective portion 70 (see FIG. 8 ) includes a guide 72 (first guide 72) and a second guide 73. The second guide 73 is located on the opposite side of the inner wall 713, approximately 180 degrees from the central axis C1, and is located inward of the cover 71 in the width direction of the machine body. The second guide 73 is separated from the first guide 72. The space between the first guide 72 and the second guide 73 is included in the displacement region K2 of the lever 62. The outer side (outer periphery) of the second guide 73 is a region through which the hose 80 can pass (see FIG. 5 ), and the outer region of the second guide 73 is continuous with the passage region K1. Because the second guide 73 may come into contact with the hose 80, a round bar 73 a is provided at its end as an edge guard, and the end of the second guide 73 has a convex, rounded shape.
[0057] In this embodiment (see FIGS. 4, 5, 7, and 8), the guide 72 is integral with the cover 71. That is, the guide 72 and the cover 71 are connected. The guide 72 is fixed along the inner peripheral edge of the inner wall 713, for example, by welding. The protective unit 70, which integrally includes the guide 72 and the cover 71, is attached to the tip 43 of the boom 31 with bolts 75. The protective unit 70 can be removed from the boom 31 by removing the bolts 75. That is, the protective unit 70 is detachable from the boom 31. This configuration makes it easy to attach the protective unit 70 (the cover 71 and the guide 72) to the boom 31 and also makes it easy to replace the protective unit 70.
[0058] The cover 71 is provided so as to cover the detection body 61 and lever 62 of the angle detector 60. The cover 71 is attached to the tip 43 of the boom 31 with a gap between the detection body 61 and the lever 62. The guide 72 is provided so as to cover part of the periphery of the detection body 61 and bracket 55 of the angle detector 60. The guide 72 is provided at the tip 43 of the boom 31 with a gap between the detection body 61 and the bracket 55.
[0059] In this manner, the cover 71 and the guide 72 are attached to the boom 31 without contacting the angle detector 60. The detection body 61 (see FIG. 4 ) is disposed inside the outer edge (outer peripheral surface) 55a of the bracket 55 when viewed from the direction along the central axis C1. The inner peripheral surface 72b of the guide 72 (see FIG. 7 ) has a shape (arc shape) that follows the outer edge (outer peripheral surface) 55a of the bracket 55, and the inner peripheral surface 72b of the guide 72 faces the outer peripheral surface 55a of the bracket 55. With this configuration, even if a large force acts on one or both of the cover 71 and the guide 72, or even if one or both of the cover 71 and the guide 72 are deformed by that force, the guide 72 abuts against the bracket 55 and does not come into contact with the angle detector 60, and the angle detector 60 is not affected by the force.
[0060] Figure 9 is an explanatory diagram showing a modified example of the protector 70. In the case of the protector 70 shown in Figure 9, the guide 72 is separate from the cover 71. That is, the guide 72 is separated from the cover 71. The guide 72 is fixed to the bracket 55 by welding or the like. The cover 71 is attached to the tip 43 of the boom 31 with a first bolt 75. The bracket 55, which is integral with the guide 72, is attached to the tip 43 of the boom 31 with a second bolt 76. That is, the guide 72 is attached to the tip 43 of the boom 31 together with the bracket 55.
[0061] The detection body 61 is attached to the bracket 55 by a third bolt 77. When the second bolt 76 is removed, the guide 72 and the bracket 55 become one unit, and are removed together with the detection body 61 from the tip 43 of the boom 31. In the embodiment shown in FIG. 9 , the cover 71 is separate from the guide 72 and the bracket 55. Therefore, even if a large force acts on the cover 71 or the cover 71 is deformed by that force, the effect is unlikely to be felt by the detection body 61.
[0062] In the embodiment shown in Fig. 9, similar to the embodiment shown in Fig. 4, the cover 71 is provided so as to cover the detection main body 61 and the lever 62 of the angle detector 60. The cover 71 is attached to the tip 43 of the boom 31 with a gap between the detection main body 61 and the lever 62. The guide 72 is provided so as to cover part of the periphery of the detection main body 61. The guide 72 is provided at the tip 43 of the boom 31 with a gap between the detection main body 61 and the guide 72.
[0063] In this way, the cover 71 is attached to the boom 31 side without contacting the angle detector 60, and the guide 72 is attached to the boom 31 side without contacting the detection body 61. With this configuration, even if a large force acts on the cover 71 or the cover 71 is deformed by that force, the angle detector 60 is not affected.
[0064] [Regarding the Work Machine 10 of the Present Embodiment] As described above, the work machine 10 of the present embodiment (see FIG. 1) has the machine body 11 and the arm device 13 that is integrated with the machine body 11. The arm device 13 (see FIGS. 2 and 3) has a boom (first arm) 31, an arm (second arm) 32 that swings around a central axis C1 relative to the boom 31, an angle detector 60, a protector 70, and a hose 80. The angle detector 60 is a device for detecting the angle formed between the boom 31 and the arm 32. The protector 70 is a member that protects the angle detector 60. The hose 80 is provided at the connection portion 37 between the boom 31 and the arm 32.
[0065] The angle detector 60 includes a detection body 61 provided on the boom 31 side and a lever 62 connected to the detection body 61 and the mounting member 56 on the arm 32 side. The lever 62 is displaced in response to the relative swing of the boom 31 and the arm 32. The protective section 70 (see FIGS. 4 and 5 ) includes a cover 71 and a guide 72. The cover 71 covers a displacement region K2 of the lever 62. The guide 72 has a smaller profile than the cover 71 when viewed from the direction along the central axis C1, and is positioned so as to overlap the cover 71 when viewed from the direction along the central axis C1, thereby covering the detection body 61. In this embodiment (see FIG. 6 ), the area between the base 51 of the arm 32 and the cover 71 and outside the guide 72 is a passage region K1 through which a hose 80 curved around the detection body 61 passes.
[0066] According to the work machine 10 having the above-described configuration, the hose 80 is positioned around the detection main body 61 of the angle detector 60 in a small curve, making a short length. The hose 80 is positioned around the detection main body 61 in a small curve, making a small curve, but the guide 72 is interposed between the hose 80 and the detection main body 61. Therefore, the hose 80 does not interfere with the detection main body 61.
[0067] The portion of the hose 80 that curves around the detection body 61 and passes through the passage area K1 is hidden by the cover 71. The hose 80 is arranged more smartly than before. The hose 80 is arranged to be short and maneuverable, which makes it possible to reduce the number of clamps used to secure the hose 80 to the boom 31 or the arm 32.
[0068] The hose 80 may come into contact with the guide 72. Even if the guide 72 is damaged or the coating on the painted guide 72 peels off, the guide 72 is hidden by the cover 71. Therefore, the appearance is not impaired.
[0069] The cover 71 covers the displacement region K2 of the lever 62 and the detection body 61 (see FIG. 5 ). Therefore, for example, even if the arm device 13 rotates and the connection portion 37 between the boom 31 and the arm 32 is likely to come into contact with a structure, the cover 71 comes into contact with the structure before the angle detector 60 does. Furthermore, the lever 62 and the detection body 61 do not come into direct contact with the structure. Therefore, for example, it is possible to prevent deformation of the lever 62. The protective portion 70 prevents a decrease in the detection accuracy of the angle detector 60 and damage to the angle detector 60.
[0070] The cover 71 is attached without contacting the detection body 61 and the lever 62 of the angle detector 60. Therefore, even if the cover 71 comes into contact with, for example, a structure and is deformed, the effect is unlikely to be felt on the detection body 61 and the lever 62. In other words, it is possible to prevent breakdown of the angle detector 60. Even if the cover 71 is damaged, the cover 71 can be easily removed from the tip 43 of the boom 31 with bolts 75, and the cover 71 can be easily replaced.
[0071] [Others] In the above-described embodiment, the arm device 13 has a first arm (boom 31) and a second arm (arm 32) as arms. The arm device 13 may have three or four or more arms, rather than only two. For example, when the arm device 13 has three arms, the arm device 13 has two connecting portions (joint portions). Two adjacent arms sandwiching the connecting portion swing relatively. In this case, an angle detector 60 is provided on the first arm, which is one of the two adjacent arms. The lever 62 of the angle detector 60 is attached to a member provided on the second arm, which is the other of the two adjacent arms. An angle detector 60 and a protector 70 are provided on each of the connecting portions. The protector 70 has the configuration shown in each of the above-described embodiments.
[0072] In the case of the above embodiment, the detection body 61 of the angle detector 60 is provided on the tip 43 of the boom 31, and the lever 62 is connected to the mounting member 56 (see FIG. 3 ) of the arm 32. Although not shown, the detection body 61 may alternatively be provided on the arm 32 side, and the lever 62 may be connected to a member provided on the boom 31. In this case, the arm 32 is the first arm, and the boom 31 is the second arm.
[0073] In this embodiment (e.g., Figures 4 and 5), the tip 43 of the boom 31 has a bifurcated shape, and the base 51 of the arm 32 is located between the first frame 431 and the second frame 432. The structure of the connecting portion 37 between the boom 31 and the arm 32 may be other than that shown in the drawings. The work machine 10 in this embodiment is a backhoe, but may be another type of work machine. When the work machine 10 is a backhoe, the backhoe is not limited to the illustrated form and can be modified within the scope of the present invention.
[0074] The above-described embodiments are illustrative in all respects and are not limiting. The scope of the present invention is defined by the claims rather than the above-described embodiments, and includes all modifications within the scope equivalent to the configurations described in the claims.
[0075] REFERENCE SIGNS LIST 10 Work machine 11 Machine body 13 Arm device 31 Boom (first arm) 32 Arm (second arm) 37 Connection portion 43 Tip portion 44 End surface (boom end surface) 55 Bracket 56 Mounting member (member on second arm side) 60 Angle detector 61 Detector body 62 Lever 70 Protective portion 71 Cover 711 Outer wall 712 Outer wall 713 Inner wall 714 Auxiliary wall 72 Guide 72a Outer surface 72b Inner surface 80 Hose C1 Central axis K1 Passing area K2 Displacement area
Claims
1. A work machine comprising: a body; and an arm device, wherein the arm device comprises: a first arm; a second arm that swings around a central axis relative to the first arm; an angle detector for detecting the angle between the first arm and the second arm; a protective section that protects the angle detector; and a hose provided at a connection between the first arm and the second arm, wherein the angle detector comprises: a detection body provided on the first arm side; and a lever that is connected to the detection body and a member on the second arm side and displaces in accordance with the relative swing of the first arm and the second arm, wherein the protective section comprises: a cover that covers a displacement region of the lever; and a guide that covers the detection body and has a contour shape smaller than that of the cover when viewed from a direction along the central axis and is positioned so as to overlap the cover when viewed from a direction along the central axis, wherein a passing region through which the hose passes is provided between the first arm or the second arm and the cover and outside the guide.
2. The work machine according to claim 1, wherein the guide has an outer peripheral surface whose contour shape when viewed from a direction along the central axis is a circular arc, and the passing area is provided along the outer peripheral surface.
3. A work machine as described in claim 1 or claim 2, wherein the first arm has an arc-shaped end face at a tip portion where the angle detector is provided, the end face and the guide are positioned side by side in a direction parallel to the central axis, and the passing area is between the second arm and the cover and is provided in an area outside the guide and the end face.
4. A work machine as set forth in claim 1 or 2, wherein the guide is integral with the cover, and the guide and the cover are detachable from the first arm.
5. A work machine as described in claim 4, further comprising a bracket for attaching the detection body to the first arm, the detection body being positioned inside the outer edge of the bracket when viewed from a direction along the central axis, and the inner circumferential surface of the guide facing the outer circumferential surface of the bracket.
6. A work machine as described in claim 1 or claim 2, wherein the first arm has a bracket for mounting the detection body, the guide is integral with the bracket, and the cover is separate from the guide and the bracket.
7. A work machine according to claim 1 or 2, wherein the cover and the guide are attached to the first arm side in a non-contact state with the angle detector.
8. A work machine as described in claim 1 or claim 2, wherein the cover has an outer peripheral wall covering the outside of the displacement area of the lever, an outer wall connected to the outer peripheral wall and covering the angle detector from the outside in the width direction of the machine body, and an inner wall connected to the outer peripheral wall and positioned inward in the width direction of the machine body than the outer wall and facing the outer wall, and the inner wall is positioned outward in the width direction of the machine body of the hose passing through the passing area.
9. A work machine as described in claim 8, wherein the outer wall is provided over almost the entire circumferential area of the outer peripheral wall centered on the detection body, the inner wall is provided corresponding to a portion of the circumferential area of the outer peripheral wall centered on the detection body, and the displacement area of the lever is included in a range of the cover where the inner wall is not provided.
10. The work machine according to claim 9, wherein the length of the guide in a circumferential direction about the detection body is longer than the length of the inner wall in the circumferential direction.
11. A work machine as set forth in claim 1 or 2, wherein the cover has an arc-shaped outer peripheral wall that covers the outside of the displacement area of the lever that is formed in an arc shape around the central axis.