JP6581065B2 - Work machine - Google Patents

Description

  The present invention relates to a work machine equipped with an attachment such as a fork grapple equipped with a hydraulic actuator.

  Various work tools are attached to work arms of a work machine such as a hydraulic excavator as an attachment depending on the application. When a work tool equipped with a hydraulic actuator such as a fork grapple is mounted, a pipe joint provided on the work tool is connected to a pipe joint of the work arm with a hydraulic hose. This hydraulic hose needs a margin of length to allow the work tool to rotate as the work tool cylinder expands and contracts. On the other hand, if the slack of the hydraulic hose is large, the hydraulic hose may be caught by surrounding obstacles such as reinforcing bars. In view of this, a hose guide is provided in a link connecting the work tool and the work arm, and the hydraulic hose is not easily caught on an obstacle or the like by passing the hydraulic hose through the hose guide (see Patent Document 1).

Japanese Patent Laying-Open No. 2015-40455

  However, a high pressure resistant hose used for a hydraulic hose has a minimum bending radius, and the hydraulic hose cannot be bent beyond the curvature defined by the minimum bending radius. For this reason, it may be necessary to allow the hydraulic hose to have a length longer than simply allowing the work implement to rotate, and the hydraulic hose is slackened simply by pressing the middle part of the hydraulic hose with the hose guide provided on the link. May not be sufficiently suppressed.

  An object of the present invention is to provide a work machine that can sufficiently suppress the slack of a hydraulic hose that connects a work tool having a hydraulic actuator and a work arm, and can suppress the occurrence of interference with an obstacle or the like of the hydraulic hose. It is in.

  To achieve the above object, the present invention provides a work machine main body, a work arm rotatably connected to a front portion of the work machine main body, and a hydraulic actuator rotatably connected to a tip of the work arm. A working machine having a work tool with a first link having one end rotatably connected to the work arm, and a second link having both ends rotatably connected to the first link and the work tool. A work tool cylinder having both ends pivotably connected to at least one of the first link and the second link and the work arm, a base frame fixed to the first link, and a support to the base frame A first pulley and a second pulley mounted on the shaft, at least one of which is slidable along the shaft, and the first pulley and the second pulley mounted on the shaft. A spring for applying a spring force in the direction of reversal, and a pipe for connecting the working arm and a pipe joint provided on the work tool to pass hydraulic oil supplied to and discharged from the hydraulic actuator of the work tool, A flexible hydraulic hose hung around the first pulley and the second pulley is provided.

  According to the present invention, it is possible to sufficiently suppress the slack of the hydraulic hose connecting the work tool including the hydraulic actuator and the work arm, and to suppress the occurrence of interference with the obstacle of the hydraulic hose.

1 is a side view of a work machine according to an embodiment of the present invention. It is an enlarged view of the working tool with which the working machine shown in FIG. 1 was equipped. It is the side view which extracted and represented the working arm and working tool in the state which extended the working tool cylinder in the working machine shown in FIG. It is the top view showing the structure of the tension apparatus with the upper surface of the front-end | tip part of the arm with which the working machine shown in FIG. 1 was equipped. It is a perspective view of the tension device with which the working machine shown in FIG. 1 was equipped. It is an exploded view of the tension device with which the working machine shown in FIG. 1 was equipped. It is the side view which extracted and represented the work arm and the working tool in the state which contracted the working tool cylinder in the working machine shown in FIG. It is the side view which extracted and represented the work arm and work tool in the state where the work tool cylinder was extended in the work machine concerning one comparative example. It is the side view which extracted and represented the work arm and the work tool in the state which contracted the work tool cylinder in the working machine concerning one comparative example.

  Embodiments of the present invention will be described below with reference to the drawings.

1. Work Machine FIG. 1 is a side view of a work machine according to an embodiment of the present invention. Thereafter, the front side (left side in FIG. 1), rear side (right side), left side (front side in the direction orthogonal to the paper surface in FIG. , Rear, left, and right are simply referred to as front, rear, left, and right, respectively. In FIG. 1, a tension device, which will be described later, is omitted in order to prevent congestion. The working machine shown in the figure has a hydraulic excavator as a base machine, and exemplifies a form in which a fork grapple is mounted as a work tool 22 as a work attachment to a work arm 21 (described later).

  The work machine includes a work machine main body 10 and a work machine (front work machine) 20 attached to the work machine main body 10.

  The work machine body 10 includes a traveling body 11 and a revolving body 12. The traveling body 11 is a crawler traveling body that forms the base structure of the work machine and includes left and right crawler belts. The left and right crawler belts are respectively driven by individual traveling motors. The revolving body 12 is provided on the traveling body 11 via a revolving wheel 13, and the revolving wheel 13 is driven by a revolving motor (not shown) so that the revolving body extends vertically with respect to the traveling body 11. Turn. The swivel body 12 includes a cab 14 in which a driver's seat (not shown) where an operator sits and an operating device (not shown) operated by the operator are arranged. The travel motor and the turning motor are hydraulic motors, but an electric motor may be used.

  The work machine 20 includes a work arm 21 and a work tool 22 with a hydraulic actuator. The work arm 21 in this embodiment is an articulated work device including a boom 23, an arm 24, a boom cylinder 25, an arm cylinder 26, and a work tool cylinder 27. The boom 23 is connected to the front portion of the base frame (the turning frame 15) of the revolving structure 12 so as to be able to turn in the vertical direction via a shaft extending left and right. The arm 24 is rotatably connected to the tip of the boom 23 through a shaft extending in the left-right direction. The boom cylinder 25 is connected to the swing body 12 and the boom 23, and the arm cylinder 26 is connected to the boom 23 and the arm 24, respectively. The work tool cylinder 27 has a proximal end connected to the base side of the arm 24 and a distal end connected to the first link 28 and the second link 29. The boom cylinder 25, the arm cylinder 26, and the work tool cylinder 27 are all hydraulic cylinders.

  One end of the first link 28 is rotatably connected to the arm 24 via a shaft extending left and right. The connection position of the first link 28 with respect to the arm 24 is located closer to the arm proximal side than the connection position of the arm 24 to the work tool 22 (pin hole 36 in FIG. 2). The other end of the first link 28 is rotatably connected to the second link 29 and the work tool cylinder 27 via a shaft extending left and right. In the posture of FIG. 1 with the arm 24 and the work tool 22 facing downward, the other end of the first link 28 is located on the front side of the arm 24. The second link 29 has one end connected to the work tool 22 and the other end of the first link 28 and the other end connected to the work tool cylinder 27 so as to be rotatable. The connection position of the second link 29 and the work tool 22 is located in front of the connection position of the second link 29 and the arm 24 in the posture of FIG. Although FIG. 1 illustrates a structure in which the work tool cylinder 27 is coaxially connected to both the first link 28 and the second link 29, the work tool cylinder 27 can rotate to either the first link 28 or the second link 29. It may be a configuration linked to. In the present embodiment, a pair of such first links 28 and second links 29 are provided on the left and right sides of the arm 24.

2. Working Tool FIG. 2 is an enlarged view of the working tool. The work tool 22 shown in the figure is a fork grapple, and includes a bracket 31, a turning device 32, a frame 33, a fork 34, and a hydraulic cylinder 35. The bracket 31 has pin holes 36 and 37. The tip end of the arm 24 is connected to the pin hole 36, and one end of the second link 29 is connected to the pin hole 37 so as to be rotatable (see FIG. 1). As a result, the work tool 22 is rotatably connected to the tip of the arm 24, and the work tool 22 rotates through the first link 28 and the second link 29 as the work tool cylinder 27 extends and contracts. The frame 33 is attached to the bracket 31 via a turning device 32. Although not shown, the turning device 32 includes a turning wheel and a turning motor. A fork 34 is attached to the frame 33. The fork 34 includes claws 38 and 39 each having a plurality of sets. The claws 38 and 39 are rotatably attached to the frame 33 via pins 41 and 42, respectively. One end of the hydraulic cylinder 35 is connected to the frame 33 via a pin 43 and the other end is connected to a claw 39 via a pin 44. The claws 38 and 39 are connected by an interlocking link 45. The claw 39 rotates as the hydraulic cylinder 35 expands and contracts, and the claw 38 rotates as the claw 39 rotates. As a result, the fork 34 opens and closes. The turning motor of the turning device 32 and the hydraulic cylinder 35 are hydraulic actuators provided in the work tool 22.

3. Hydraulic Hose FIG. 3 is a side view of the working arm and working tool extracted. In FIG. 3, the work tool cylinder 27 is not shown. As shown in the figure, at least one (three in this example) pipe joint 51 is provided on the left side surface of the arm 24. The pipe joint 51 is connected to a hydraulic pump (not shown) and a hydraulic oil tank (not shown) via a control valve (not shown) mounted on the swing body 12. At least one pipe joint 52 is also provided on the left side surface of the bracket 31 of the work tool 22. Although only one pipe joint 52 is shown in FIG. 3, at least two pipe joints 52 are necessary because the pipe joint 52 is individually connected to the swing motor and the hydraulic cylinder 35 (FIG. 2) mounted on the work tool 22. It is. The pipe joints 51 and 52 are connected by at least one flexible hydraulic hose 53. The hydraulic hose 53 is a pipe line through which hydraulic oil supplied to and discharged from a hydraulic actuator (swing motor or hydraulic cylinder 35) provided in the work tool 22 is passed. Although only one hydraulic hose 53 is shown in the present embodiment, when both the turning function and the claw opening / closing function of the work tool 22 are used, the pipe joints 51 and 52 are connected by at least two hydraulic hoses 53. The The length of the hydraulic hose 53 is longer than the interval between the pipe joints 51 and 52 when the work tool cylinder 27 extends and the distance between the pipe joints 51 and 52 becomes the longest. The hydraulic hose 53 is hung around the tensioning device 60.

  Although not shown in FIG. 3, the pipe joints 51, 52, the hydraulic hose 53, and the tensioning device 60 are provided one by one on the left and right sides, and the left side surface of the arm 24 of the work arm 21 and the bracket 31 of the work tool 22. Not only on the right side, but also on the right side.

4). FIG. 4 is a plan view showing the configuration of the tensioning device together with the upper surface of the arm tip, FIG. 5 is a perspective view of the tensioning device, and FIG. 6 is an exploded view of the tensioning device. As described above, one tensioning device 60 is provided on each of the left and right sides of the arm 24, and the left and right ones have the same configuration except that they are bilaterally symmetrical (see FIG. 4). 5 and 6 show the tensioning device 60 on the left side. The tensioning device 60 is a device that absorbs slack in the hydraulic hose 53, and includes a base frame 61, a shaft 62, a first pulley 63, a second pulley 64, and a spring 65.

  The base frame 61 is a base frame of the tensioning device 60, and is fixed to the first link 28 so as to extend outward in the left-right direction of the arm 24 (left side in the case of the left tensioning device 60). Therefore, for example, the base frame 61 of the left tension device 60 extends leftward from the left first link 28, and the base frame 61 of the right tension device 60 extends rightward from the right first link 28. . In the present embodiment, a configuration in which one base frame 61 is disposed between the first pulley 63 and the second pulley 64 is illustrated. For example, two bases are sandwiched between the first pulley 63 and the second pulley 64. A configuration in which the frame 61 is provided may be employed.

  Although a bar-shaped base frame 61 fixed in a posture orthogonal to the first link 28 is illustrated, a hydraulic hose 53 passes between the first pulley 63 and the second pulley 64 as described later. Accordingly, the shape, arrangement, dimensions, and the like of the base frame 61 are appropriately set so as not to interfere with the hydraulic hose 53 that passes between the first pulley 63 and the second pulley 64. If the simple bar-shaped base frame 61 is disposed between the first pulley 63 and the second pulley 64 and interference with the hydraulic hose 53 is unavoidable, for example, an opening or a slit through which the hydraulic hose 53 passes is provided. The base frame 61 may be formed in a shape.

  Two shafts 62 are provided side by side on the left and right tension devices 60, and two shafts 62 are fixed and supported on each base frame 61 in a posture extending in the extending direction of the first link 28. In the present embodiment, the two shafts 62 are supported by the base frame 61 at the intermediate portion in the longitudinal direction. The cross-sectional shape of the shaft 62 is not limited, but is circular in this embodiment. In the present embodiment, the two shafts 62 provided in one tensioning device 60 have the same length, and have male threads at both ends.

  The first pulley 63 and the second pulley 64 include a pulley 66 and a support member 67, respectively. The radius of the first pulley 63 and the second pulley 64 is equal to or greater than the minimum bending radius of the hydraulic hose 53 (value determined by the specifications of the hydraulic hose 53). The pulley 66 is a disk on which the hydraulic hose 53 is hung, and a V pulley is used in this embodiment. The rotation axis of each pulley 66 extends in the same direction (that is, the left-right direction) as the extending direction of the axis of the first link 28 (for example, the axis connecting to the arm 24), and the pulley 66 is along a vertical plane. The support member 67 is a support member that rotatably supports the rotation shaft of the pulley 66, and is disposed on both sides of the pulley 66 to support both ends of the rotation shaft. The support member 67 has a through hole through which the shaft 62 passes. The two support members 67 of the first pulley 63 are respectively attached to the shaft 62 from one end of the first link 28 (side connected to the arm 24). The two support members 67 of the second pulley 64 are respectively attached to the shaft 62 from the other end of the first link 28 (the side connected to the second link 29). That is, the first pulley 63 is slidably mounted on one side of the shaft 62 (the side close to one end of the first link 28), and the second pulley 64 is close to the other side of the shaft 62 (close to the other end of the first link 28). Side) is slidably mounted.

  The spring 65 is a coil spring that allows the shaft 62 to pass inside. The spring 65 is attached to the shaft 62 and applies a spring force in a direction that separates the first pulley 63 and the second pulley 64. In the case of the present embodiment, springs 65 are interposed between the support members 67 and the base frame 61 of the first pulley 63 and the second pulley 64, and four springs 65 are used for one tensioning device 60. It has been. Each spring 65 biases the support member 67 in a direction away from the base frame 61. Note that nuts 68 (see FIG. 4, omitted in other drawings) are attached to both ends of each shaft 62 to limit the slidable range of the support member 67 in the direction away from the base frame 61. By tightening or loosening these nuts 68, the slidable range of the first pulley 63 and the second pulley 64 can be adjusted.

  The hydraulic hose 53 is wound around the first pulley 63 and the second pulley 64. In describing the winding path of the hydraulic hose 53 with respect to the first pulley 63 and the second pulley 64, in this embodiment, a connection portion with the pipe joint 51 provided on the arm 24 of the work arm 21 is used as a base end of the hydraulic hose 53. To do. Explaining the piping path of the hydraulic hose 53 from the base end side, the hydraulic hose 53 is first wound around the first pulley 63 from the side far from the second pulley 64 and further passes between the first pulley 63 and the second pulley 64. Then, it is hung around the second pulley 64 and finally connected to the pipe joint 52 provided on the work tool 22. That is, as shown in FIG. 3, the hydraulic hose 53 is wound around the first pulley 63 and the second pulley 64 through a path in which the alphabet S is reversed left and right as viewed from the left side. When viewed from the right side, the method of engaging the hydraulic hose 53 with respect to the first pulley 63 and the second pulley 64 is S-shaped. The diameter, interval, and variable amount of the first pulley 63 and the second pulley 64 can be adjusted so that the hydraulic hose 53 is connected to the first pulley 63 and the first pulley 63 even when the work tool cylinder 27 contracts and the distance between the pipe joints 51 and 52 becomes the shortest. Two pulleys 64 are set so as not to come off.

5). Operation As the work tool cylinder 27 extends, the work tool 22 rotates with respect to the arm 24 in the vertical plane. For example, when the work tool cylinder 27 is contracted from the state in which the work tool cylinder 27 is extended as shown in FIG. 3, the work tool 22 rotates upward (the dump side referred to as an excavator) as shown in FIG. The first link 28 rotates from a posture (FIG. 3) toward the arm distal end side (FIG. 7) toward the arm proximal end side, with the one end connected to the arm 24 as a fulcrum. When the work tool cylinder 27 is extended, the reverse operation is performed. Thus, when the work tool 22 rotates, the tensioning device 60 also rotates together with the first link 28. At that time, the first pulley 63 and the second pulley 64 roll on the hydraulic hose 53 and change the distance between them by the expansion and contraction of the spring 65 according to the force received from the hydraulic hose 53. As a result, an appropriate tension always acts on the hydraulic hose 53.

6). Effect (1) Suppression of slackening of hydraulic hose FIGS. 8 and 9 are side views of the working arm and the work tool provided in the working machine according to a comparative example. 8 and 9 correspond to FIGS. 3 and 7. In the configuration according to the comparative example, the tensioning device 60 is not provided. The hydraulic hose H needs to be longer than the maximum distance between the pipe joints C and D of the arm A and the work tool B in order to allow the work tool B to rotate with respect to the arm A. Therefore, for example, when the work tool B is turned from the cloud side (FIG. 8) to the dump side (FIG. 9), which is called an excavator, the pipe joints C and D approach as shown in FIG. H slack increases. In FIG. 9, the hydraulic hose H slackened when viewed from the left and right direction protrudes greatly downward from the outer shape of the arm A. In such a state, for example, when the swivel body 12 is swung, the hydraulic hose is easily caught by a surrounding obstacle such as a reinforcing bar.

  On the other hand, in this embodiment, the hydraulic hose 53 is wound around the first pulley 63 and the second pulley 64 which are elastically supported by the spring 65 and change in interval, and appropriate tension is always applied to the hydraulic hose 53. Yes. Thereby, as shown in FIG.3 and FIG.7, the slack of the hydraulic hose 53 which changes a magnitude | size with the rotation of the working tool 22 can be absorbed. Accordingly, the slack of the hydraulic hose 53 connecting the work tool 22 having the hydraulic actuator and the work arm 21 can be sufficiently suppressed, and the occurrence of interference with an obstacle or the like of the hydraulic hose 53 can be suppressed.

(2) Length control of hydraulic hose If the tensioning device 60 is directly attached to the arm 24 so as not to rotate with respect to the arm 24, the arm of the pipe joint 52 of the work tool 22 accompanying the turning motion of the work tool 22. The displacement amount with respect to 24 is directly reflected in the relative positional relationship between the pipe joint 52 and the tensioning device 60. Therefore, the amount of change in the distance from the tensioning device 60 connected to the hydraulic hose 53 to the pipe joint 52 is large, and the spring 65 needs to be lengthened because the variable amount of the distance between the first pulley 63 and the second pulley 64 needs to be increased. is there.

  In the present embodiment, the hydraulic hose 53 is hung around the first pulley 63 and the second pulley 64 in an S shape (strictly, an inverted S shape when viewed from the left side), and the route is followed from the base end of the hydraulic hose 53. Finally, the hydraulic hose 53 is connected to the pipe joint 52 via the second pulley 64. At this time, since the tensioning device 60 is provided on the first link 28, the tensioning device 60 rotates together with the first link 28, and follows the displacement of the pipe joint 52 accompanying the rotation of the work tool 22. Move. Since the second pulley 64 has a fixed positional relationship with respect to the other end of the second link 29, the second pulley 64 swings with the second link 29 having a fulcrum on the work tool 22 when viewed from the pipe joint 52. Will do. Since the pipe joint 52 is in a fixed positional relationship with respect to one end of the second link 29, the variation in the distance between the pipe joint 52 and the second pulley 64 accompanying the rotation of the work tool 22 is small. Therefore, the length of the spring 65 can be shortened compared to the above assumption (when the tensioning device 60 is fixed to the arm 24), and the tensioning device 60 can be configured compactly.

(3) Ensuring Durability of Hydraulic Hose In the present embodiment, the hydraulic hose 53 is folded back along the outer periphery of the first pulley 63 and the second pulley 64, but the radius of the first pulley 63 and the second pulley 64 is The minimum bending radius of the hydraulic hose 53 is set. Thereby, the hydraulic hose 53 does not bend beyond the curvature defined by the minimum bending radius, and durability according to the specifications of the hydraulic hose 53 can be ensured.

7). In the above embodiment, in FIG. 5 and the like, the first pulley 63 and the second pulley 64 have exemplified the pulley 66 having a groove having a V-shaped cross section. However, the cross-sectional shape of the groove of the pulley is not limited to the V shape and is a flat pulley. Etc. may be used. Further, although the pulley 66 having only one groove is illustrated, when it is assumed that a plurality of hydraulic hoses are hung, a pulley having a plurality of grooves may be used.

  Although the configuration in which both the first pulley 63 and the second pulley 64 are slid with respect to the shaft 62 is illustrated, either the first pulley 63 or the second pulley 64 may be fixed to the shaft 62.

  Further, although the configuration in which the shaft 62 of the tensioning device 60 extends along the first link 28 is illustrated, the shaft 62 may extend in a direction inclined with respect to the first link 28.

  The support member 61 is interposed between the first pulley 63 and the second pulley 64, and the first pulley 63 and the second pulley 64 are biased by the spring 65 with the support member 61 as a base point. Is not limited. For example, when the both ends of the shaft 62 are supported by the support member, the support member 61 between the first pulley 63 and the second pulley 64 can be omitted. In this case, a single spring 65 is interposed between the first pulley 63 and the second pulley 64 per shaft 62, and the first pulley 63 and the second pulley 64 are biased by the spring 65. be able to. The nuts 68 that limit the sliding range of the first pulley 63 and the second pulley 64 may be arranged on the center side in the longitudinal direction of the shaft 62 rather than the support members at both ends.

  Although the fork grapple used for the scrap processing and transportation of the waste material is illustrated as the work tool 22, the present invention is also applicable to the case where another work tool equipped with a hydraulic actuator is attached to the work arm 21, and in that case In addition, the tensioning device 60 functions effectively. Examples of other types of work implements equipped with hydraulic actuators include a crusher for splitting used at the site of dismantling, a breaker used for excavation and crushing of bedrock and concrete, and the like. However, although the tensioning device 60 does not function because the hydraulic hose 53 is not required, a work implement not equipped with a hydraulic actuator such as a bucket used for excavation or transportation of earth and sand or concrete glass can be mounted on the work machine of the above embodiment. .

  Further, although the case where the present invention is applied to a working machine using a hydraulic excavator having only one working arm as a base machine has been described as an example, the present invention is also applied to a double-armed working machine having two working arms. The invention is applicable. Although the working machine provided with the crawler type traveling body 11 is illustrated as the base structure, the present invention is also applicable to the working machine provided with the wheel type traveling body. The present invention is also applicable to a work machine having a hull as a base structure. In addition, the present invention can be applied to a stationary work machine in which a revolving body is provided on an upper portion of a fixed base structure such as a post fixed to the ground. Further, the present invention is not limited to a working machine using a hydraulic excavator as a base machine, but can be applied to other types of working machines such as a wheel loader in which a work tool equipped with a hydraulic actuator can be mounted on a work arm.

DESCRIPTION OF SYMBOLS 10 ... Work machine main body, 21 ... Working arm, 22 ... Work tool, 28 ... 1st link, 29 ... 2nd link, 51, 52 ... Pipe joint, 53 ... Hydraulic hose, 61 ... Base frame, 62 ... Shaft, 63 ... 1st pulley, 64 ... 2nd pulley, 65 ... Spring, disk 66, support member 67, nut 68

Claims (3)

In a work machine comprising a work machine main body, a work arm rotatably connected to a front portion of the work machine main body, and a work tool with a hydraulic actuator rotatably connected to a tip of the work arm,
A first link having one end rotatably connected to the working arm;
A second link having both ends rotatably connected to the first link and the work tool;
A work tool cylinder having both ends rotatably connected to at least one of the first link and the second link and the work arm;
A base frame fixed to the first link;
A shaft supported by the base frame;
A first pulley and a second pulley mounted on the shaft, at least one of which is slidable along the shaft;
A spring mounted on the shaft and acting on a spring force in a direction separating the first pulley and the second pulley;
A pipe line connecting the working arm and a pipe joint provided on the work tool to pass hydraulic oil supplied to and discharged from the hydraulic actuator of the work tool, and is routed around the first pulley and the second pulley. A working machine comprising a flexible hydraulic hose. The work machine according to claim 1,
The shaft extends in the extending direction of the first link, and the first pulley is mounted on the side close to one end of the first link, and the second pulley is mounted on the side close to the other end of the first link. ,
The hydraulic hose is hung on the first pulley by passing the first pulley and the second pulley through a connection portion with a pipe joint provided on the working arm as a base end. A work machine that is turned and connected to a pipe joint provided on the work implement.   2. The work machine according to claim 1, wherein radii of the first pulley and the second pulley are equal to or greater than a minimum bending radius of the hydraulic hose.

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