Work machine

Abstract

To provide a work machine which can prevent a tip attachment from excessively digging deeper than a target construction surface.SOLUTION: A work machine has: control means for semi-automatically or automatically controlling the operation of an attachment 30 so that a construction surface 73 constructed by a bucket 33 approaches a predetermined target construction surface 71, when operation to operation means is predetermined operation; setting means for setting an entry inhibition surface 72 at a position separated from the target construction surface 71 in a direction opposite to a direction in which the construction surface 73 approaches the target construction surface 71; and operation restriction means for restricting the operation of the attachment 30 so as to prevent the bucket 33 from entering to a side closer to the side of the target construction surface 71 than the entry inhibition surface 72, when the control means does not control the operation of the attachment 30.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a work machine capable of semi-automatically or automatically controlling the operation of an attachment. [Background technology]

[0002] Patent Document 1 discloses a method of controlling an attachment so that the blade tip of the bucket does not enter the target shape. An offset topography is set at a predetermined distance from a target construction topography, which is the target shape of the finished construction target, and the offset topography is set as the target shape during excavation, and the target construction topography is set as the target shape during compaction work. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2016 / 129708 Summary of the Invention [Problem to be solved by the invention]

[0004] In a work machine, the operation of the attachment is controlled semi-automatically or automatically so that the construction surface approaches the target construction surface. However, when the attachment starts to operate, the attachment may behave differently from the target behavior (such as the bucket (tip attachment) dropping slightly) due to cylinder compression, structural rattle, vehicle body rocking, etc. In this case, if the bucket is close to the target construction surface, there is a risk that the bucket will come into contact with the target construction surface and dig deeper than the target construction surface.

[0005] An object of the present invention is to provide a work machine that can prevent an end attachment from digging too deeply beyond a target construction surface. [Means for solving the problem]

[0006] The present invention is characterized by having a machine body, an attachment provided on the machine body and equipped with a tip attachment, an operating means for operating the attachment, a control means for semi-automatically or automatically controlling the operation of the attachment so that, when a predetermined operation is performed on the operating means, a construction surface constructed by the tip attachment approaches a predetermined target construction surface, a setting means for setting a no-entry surface at a position away from the target construction surface in the direction opposite to the direction in which the construction surface approaches the target construction surface, and an operation limiting means for limiting the operation of the attachment so that the tip attachment does not enter the target construction surface side of the no-entry surface when the control means is not controlling the operation of the attachment. Effect of the Invention

[0007] According to the present invention, when the operation by the operating means is a predetermined operation, the operation of the attachment is semi-automatically or automatically controlled so that the construction surface constructed by the tip attachment approaches a preset target construction surface. On the other hand, when the operation of the attachment is not controlled, the operation of the attachment is restricted so that the tip attachment does not enter the target construction surface side of the entry prohibited surface. Before the operation of the attachment is controlled, for example, the tip attachment may be moved to a control start position near the entry prohibited surface. At this time, the operation of the attachment is restricted so that the tip attachment does not enter the target construction surface side of the entry prohibited surface, so that the target construction surface and the tip attachment are separated. Therefore, when the control of the operation of the attachment is started in this state, even if the attachment behaves differently from the target behavior (such as the tip attachment slightly dropping), it is possible to prevent the tip attachment from hitting the target construction surface. This makes it possible to prevent the tip attachment from digging too deep beyond the target construction surface. In addition, before the operation of the attachment is controlled, for example, the tip attachment may move toward the forbidden surface due to an erroneous operation, etc. In this case, too, the operation of the attachment is restricted so that the tip attachment does not enter the target construction surface side of the forbidden surface, so that the tip attachment can be prevented from hitting the target construction surface. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. 2 is a functional configuration diagram of a work machine. [Diagram 3] FIG. 1 is a side view of a work machine in which the operation of an attachment is semi-automatically controlled. [Figure 4] FIG. 1 is a side view of a work machine in which operation of an attachment is not semi-automatically controlled. [Diagram 5] 13 is a diagram showing the relationship between the relative distance L and the maximum value of the velocity in the y direction. FIG. [Figure 6] FIG. 13 is a diagram showing the relationship between the relative distance L and the maximum value of the velocity in the positive direction of the x-axis. [Figure 7] FIG. 13 is a diagram showing the relationship between the relative distance L and the maximum value of the velocity in the negative direction of the x-axis. [Figure 8] FIG. 2 is a top view of the work machine and the no-entry surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0010] (Work machine configuration) The work machine according to this embodiment is capable of semi-automatically or automatically controlling the operation of the attachment. As shown in Fig. 1, which is a side view of the work machine 1, the work machine 1 is a machine that performs work using an attachment 30, such as a hydraulic excavator. The work machine 1 has a machine body 24 equipped with a lower traveling body 21 and an upper rotating body 22, the attachment 30, and a cylinder 40.

[0011] The lower traveling structure 21 is a portion that causes the work machine 1 to travel, and is equipped with, for example, crawlers. The upper rotating structure 22 is attached to the upper part of the lower traveling structure 21 so as to be able to rotate via a rotating device 25. A cab (operator's compartment) 23 is provided at the front part of the upper rotating structure 22.

[0012] A plurality of operating levers (operating means) 29 are provided in the cab 23. The operating levers 29 are operated by an operator. The operating levers 29 are used to operate an attachment 30.

[0013] The attachment 30 is attached to the upper rotating body 22 so as to be rotatable in the vertical direction. The attachment 30 includes a boom 31, an arm 32, and a bucket 33. The boom 31 is attached to the upper rotating body 22 so as to be rotatable (raised and lowered) in the vertical direction. The arm 32 is attached to the boom 31 so as to be rotatable in the vertical direction. The bucket 33 is a tip attachment that is the tip of the attachment 30, and is attached to the arm 32 so as to be rotatable in the front-to-rear direction of the upper rotating body 22. The bucket 33 is a part that performs tasks such as excavating, leveling, and scooping soil and sand.

[0014] The types of bucket 33 include a standard bucket, a wide bucket that is wider than the standard bucket, a narrow bucket that is narrower than the standard bucket, a slope bucket with a flat bottom, etc. The tip attachment is not limited to the bucket 33.

[0015] The cylinder 40 is capable of hydraulically rotating the attachment 30. The cylinder 40 is a hydraulic telescopic cylinder. Note that the cylinder 40 may be an electric cylinder. The cylinder 40 includes a boom cylinder 41, an arm cylinder 42, and a bucket cylinder 43.

[0016] The boom cylinder 41 rotates the boom 31 relative to the upper rotating body 22. A base end of the boom cylinder 41 is rotatably attached to the upper rotating body 22. A tip end of the boom cylinder 41 is rotatably attached to the boom 31.

[0017] The arm cylinder 42 rotates the arm 32 relative to the boom 31. A base end of the arm cylinder 42 is rotatably attached to the boom 31. A tip end of the arm cylinder 42 is rotatably attached to the arm 32.

[0018] The bucket cylinder 43 rotates the bucket 33 relative to the arm 32. A base end of the bucket cylinder 43 is rotatably attached to the arm 32. A tip end of the bucket cylinder 43 is rotatably attached to a link member 34 that is rotatably attached to the bucket 33.

[0019] The work machine 1 also has an angle sensor 52 and a tilt angle sensor 60 .

[0020] The angle sensor 52 detects the rotation angle of the upper rotating body 22 relative to the lower running body 21. The angle sensor 52 detects a current angle, which is the current rotation angle of the upper rotating body 22 relative to the lower running body 21. The angle sensor 52 is, for example, an encoder, a resolver, or a gyro sensor. In this embodiment, the rotation angle of the upper rotating body 22 when the front of the upper rotating body 22 coincides with the front of the lower running body 21 is set to 0°.

[0021] The inclination angle sensor 60 detects the attitude of the attachment 30. The inclination angle sensor 60 includes a boom inclination angle sensor 61, an arm inclination angle sensor 62, a bucket inclination angle sensor 63, and an upper rotating body inclination angle sensor (not shown).

[0022] The boom inclination angle sensor 61 and the upper rotating body inclination angle sensor are, for example, inclination (acceleration) sensors. The boom inclination angle sensor 61 is attached to the boom 31 and detects the inclination angle of the boom 31 relative to the horizontal line. The upper rotating body inclination angle sensor is provided on the upper rotating body 22 and detects the inclination angle of the upper rotating body 22 relative to the horizontal line. The angle of the boom 31 relative to the upper rotating body 22 is calculated based on the inclination angle of the boom 31 relative to the horizontal line detected by the boom inclination angle sensor 61 and the inclination angle of the upper rotating body 22 relative to the horizontal line detected by the upper rotating body inclination angle sensor. The boom inclination angle sensor 61 may be a rotation angle sensor that detects the rotation angle of a boom foot pin (boom base end) or a stroke sensor that detects the stroke amount of the boom cylinder 41.

[0023] The arm inclination angle sensor 62 is, for example, an inclination (acceleration) sensor. The arm inclination angle sensor 62 is attached to the arm 32 and detects the inclination angle of the arm 32 with respect to the horizontal line. The angle of the arm 32 with respect to the upper rotating body 22 is calculated based on the inclination angle of the arm 32 with respect to the horizontal line detected by the arm inclination angle sensor 62 and the inclination angle of the upper rotating body 22 with respect to the horizontal line detected by the upper rotating body inclination angle sensor. The arm inclination angle sensor 62 may be a rotation angle sensor that detects the rotation angle of the arm connecting pin (arm base end) or a stroke sensor that detects the stroke amount of the arm cylinder 42.

[0024] The bucket inclination angle sensor 63 is, for example, an inclination (acceleration) sensor. The bucket inclination angle sensor 63 is attached to the link member 34 and detects the inclination angle of the bucket 33 with respect to the horizontal line. The angle of the bucket 33 with respect to the upper rotating body 22 is calculated based on the inclination angle of the bucket 33 with respect to the horizontal line detected by the bucket inclination angle sensor 63 and the inclination angle of the upper rotating body 22 with respect to the horizontal line detected by the upper rotating body inclination angle sensor. The bucket inclination angle sensor 63 may be a rotation angle sensor that detects the rotation angle of the bucket connecting pin (bucket base end) or a stroke sensor that detects the stroke amount of the bucket cylinder 43.

[0025] (Functional configuration of work machine) As shown in FIG. 2, which is a functional configuration diagram of the work machine 1, the work machine 1 has a controller 11 and a storage device 13.

[0026] The storage device 13 stores a target construction surface 71 (see FIG. 3). The storage device 13 also stores a no-entry surface 72 (see FIG. 3) that is set for the target construction surface 71.

[0027] The controller 11 receives input of information relating to the rotation angle (posture) of the upper rotating body 22 relative to the lower traveling body 21 detected by the angle sensor 52. The controller 11 also receives input of information relating to the posture of the boom 31 detected by the boom inclination angle sensor 61. The controller 11 also receives input of information relating to the posture of the arm 32 detected by the arm inclination angle sensor 62. The controller 11 also receives input of information relating to the posture of the bucket 33 detected by the bucket inclination angle sensor 63.

[0028] The controller 11 switches the operation of the attachment 30 between a manual operation mode and a machine control (MC) mode. When a mode change switch (not shown) is operated, the controller 11 switches the operation of the attachment 30 between the manual operation mode and the MC mode. The mode change switch may be provided on the operation lever 29, or may be provided on a display device that displays various information, a switch console, or the like.

[0029] In the manual operation mode, the controller 11 operates the boom 31, the arm 32, and the bucket 33 in accordance with the amount of operation of the various operation levers 29 by the operator. That is, in the manual operation mode, the operator can freely operate the boom 31, the arm 32, and the bucket 33. As will be described later, the operation of the attachment 30 is restricted in the manual operation mode. Details will be described later.

[0030] On the other hand, in the MC mode, the controller (control means) 11 semi-automatically controls the operation of the attachment 30. The controller 11 semi-automatically controls the operation of the attachment 30 when the operation lever 29 is a predetermined operation. Here, in this embodiment, the predetermined operation is that in the MC mode, the operator operates the operation lever 29 for the arm 32 in a direction to pull the arm 32 toward the upper rotating body 22 side. In the MC mode, the controller 11 controls the operation of the boom 31 and the bucket 33 in accordance with the movement of the arm 32 according to the amount of operation of the operation lever 29 for the arm 32. The controller 11 semi-automatically controls the operation of the attachment 30 so that the construction surface constructed by the bucket 33 approaches a preset target construction surface. In this semi-automatic control, the detection values ​​of the angle sensor 52 and the tilt angle sensor 60 may be used.

[0031] A side view of the work machine 1 in which the operation of the attachment 30 is semi-automatically controlled is shown in Fig. 3. In Fig. 3, a target construction surface 71 is set below a construction surface 73 including a slope. In the MC mode, the operation of the attachment 30 is semi-automatically controlled so that the construction surface 73 constructed by the bucket 33 approaches the target construction surface 71. As a result, the slope shaping is performed in Fig. 3.

[0032] The semi-automatic control of the attachment 30 in the MC mode is so-called machine control. Machine control is an assist function used for finishing construction work.

[0033] Here, the target construction surface 71 is a target shape of the ground to be excavated, and is a surface that specifies a three-dimensional design topography. The target construction surface 71 is not limited to a flat surface, and may be a curved surface, etc. The target construction surface 71 may be specified by external data such as CIM (Construction Information Modeling / Management), or may be set based on the position of the upper rotating body 22.

[0034] In the MC mode, before the operation of the attachment 30 is semi-automatically controlled, in the manual operation mode, the bucket 33 is moved to a control start position and the operation of the attachment 30 is temporarily stopped. The control start position is, for example, near the construction surface 73. In this state, the manual operation mode is switched to the MC mode. Thereafter, when the attachment 30 is made to start operating, the attachment 30 may behave differently from the target behavior (such as the bucket 33 slightly dropping) due to compression of the cylinder 40, structural wobble (for example, wobble between the bucket 33 and the link member 34), swinging of the machine body 24, etc. In this case, if the bucket 33 is close to the target construction surface 71, the bucket 33 may come into contact with the target construction surface 71, and may dig deeper than the target construction surface 71.

[0035] Here, the behavior of the attachment 30 different from the target behavior means that the actual position of the bucket 33 varies from the target position of the bucket 33, or the actual speed of the bucket 33 varies from the target speed of the bucket 33. Furthermore, the bucket 33 falling means that the arm 32 falls downward at a speed equal to or greater than the speed determined by the amount of operation of the operating lever 29 for the arm 32. The behavior different from the target behavior includes not only the bucket 33 falling slightly, but also the actual position of the bucket 33 being higher than the target position.

[0036] Note that behavior different from the target behavior does not occur only in the MC mode. When the attachment 30 is paused and then started to operate, the attachment 30 may behave differently from the target behavior regardless of whether it is in the manual operation mode or the MC mode.

[0037] Therefore, as shown in FIG. 3, in this embodiment, the controller (setting means) 11 sets the entry-prohibited surface 72 at a position away from the target construction surface 71 in the direction opposite to the direction in which the construction surface 73 approaches the target construction surface 71. Like the target construction surface 71, the entry-prohibited surface 72 is not limited to a flat surface, and may be a curved surface, etc. In this embodiment, the distance between the target construction surface 71 and the entry-prohibited surface 72 is constant, but it does not have to be constant. For example, at a corner portion between the flat portion and the slope portion of the target construction surface 71, the distance between the target construction surface 71 and the entry-prohibited surface 72 may be wider than other portions, taking into account the change in posture of the attachment 30.

[0038] 4 shows a side view of the work machine 1 in which the operation of the attachment 30 is not semi-automatically controlled. When the controller (operation limiting means) 11 is in the manual operation mode and is not semi-automatically controlling the operation of the attachment 30, the controller (operation limiting means) 11 limits the operation of the attachment 30 so that the bucket 33 does not enter the target construction surface 71 side of the no-entry surface 72.

[0039] In the MC mode, before the operation of the attachment 30 is semi-automatically controlled, in the manual operation mode, the bucket 33 is moved to a control start position and the operation of the attachment 30 is temporarily stopped. The control start position is, for example, near the no-entry surface 72. At this time, the operation of the attachment 30 is restricted so that the bucket 33 does not enter the target construction surface 71 side of the no-entry surface 72, so that the target construction surface 71 and the bucket 33 are separated. Therefore, when the MC mode is switched to in this state and the semi-automatic control of the operation of the attachment 30 is started, even if the attachment 30 behaves differently from the target behavior (such as the bucket 33 slightly dropping), the bucket 33 can be prevented from hitting the target construction surface 71. This makes it possible to prevent the bucket 33 from digging too deep beyond the target construction surface 71.

[0040] Here, the work machine 1 is feedback controlled. Feedback control refers to successively detecting the speed of the tip of the bucket 33 and controlling the cylinder 40 so that this speed becomes a target speed. When semi-automatic control of the operation of the attachment 30 is started after the operation of the attachment 30 is temporarily stopped, even if the bucket 33 falls, the speed of the attachment 30 is corrected by this feedback control. Therefore, the bucket 33 is stopped before it reaches the target construction surface 71.

[0041] Furthermore, before the operation of the attachment 30 is semi-automatically controlled, for example, due to an erroneous operation, the bucket 33 may move toward the no-entry surface 72. In this case as well, the operation of the attachment 30 is restricted so that the bucket 33 does not enter the target construction surface 71 side of the no-entry surface 72, so that the bucket 33 can be prevented from hitting the target construction surface 71.

[0042] Even when the operation of the attachment 30 is semi-automatically controlled in the MC mode, the operator can operate the boom 31 and the bucket 33 by operating the operating lever 29. These operations are given priority over the semi-automatically controlled operation of the attachment 30. This is because there is a need to avoid obstacles. Furthermore, when the operation of the attachment 30 is semi-automatically controlled in the MC mode, the restriction on the operation of the attachment 30 relative to the no-entry surface 72 is lifted.

[0043] In addition, in the MC mode, the controller (control means) 11 may automatically control the operation of the attachment 30. In this case, for example, when the bucket 33 is moved to a control start position in the manual operation mode and then the mode is switched to the MC mode, the controller (control means) 11 automatically controls the operation of the attachment 30 so that the construction surface 73 constructed by the bucket 33 approaches the preset target construction surface 71. At this time, the operator does not need to perform any operation.

[0044] 4, in the manual operation mode, the closer the bucket 33 is to the forbidden entry surface 72, the more the controller (movement limiting means) 11 limits the movement of the attachment 30. Specifically, the closer the bucket 33 is to the forbidden entry surface 72, the more the controller (movement limiting means) 11 limits the movement speed of the attachment 30. Note that the method of limiting the movement of the attachment 30 is not limited to limiting the movement speed of the attachment 30.

[0045] As shown in Fig. 4, the x-axis is taken in a direction parallel to the no-entry surface 72, and the y-axis is taken in a direction perpendicular to the x-axis. The positive direction of the x-axis is the direction from top to bottom along the no-entry surface 72. The positive direction of the y-axis is the direction away from the no-entry surface 72. The relative distance between the bucket 33 and the no-entry surface 72 in the y direction is defined as L.

[0046] The relationship between the relative distance L and the maximum speed in the y direction is shown in Figure 5. The operator can operate the attachment 30 in the y direction at a speed equal to or less than the maximum speed. As shown in Figure 5, the smaller the relative distance L, the smaller the maximum speed in the y direction. When the relative distance L becomes zero, the maximum speed in the y direction becomes zero. In other words, the controller (operation restriction means) 11 restricts the bucket 33 from penetrating toward the target construction surface 71 side relative to the no-entry surface 72 along the y direction.

[0047] If the attachment 30 is suddenly decelerated or stopped near the no-entry surface 72, the machine body 24 will swing and the cylinder 40 will be compressed. If semi-automatic control of the operation of the attachment 30 is started in this state, the attachment 30 may behave differently from the target behavior (such as the bucket 33 slightly dropping). Therefore, the closer the bucket 33 is to the no-entry surface 72, the more the operation of the attachment 30 is restricted. In this way, by restricting the operation of the attachment 30 closer to the no-entry surface 72, the attachment 30 can be stopped gradually. This makes it possible to suppress the occurrence of compression of the cylinder 40 caused by suddenly decelerating or stopping the attachment 30. Therefore, when semi-automatic control of the operation of the attachment 30 is started thereafter, it is possible to suppress the attachment 30 from behaving differently from the target behavior.

[0048] On the other hand, as shown in Fig. 5, the greater the relative distance L, the greater the maximum value of the speed in the y direction. In other words, the controller (movement restriction means) 11 allows the bucket 33 to move in the y direction in a direction away from the entry restriction surface 72. This makes it possible to move the bucket 33 in a direction away from the entry restriction surface 72 even when the movement of the attachment 30 is restricted. Therefore, for example, the bucket 33 can be moved toward the control start position.

[0049] The relationship between the relative distance L and the maximum value of the velocity in the x direction is shown in Figs. 6 and 7. Fig. 6 shows the relationship between the maximum value of the velocity in the positive direction of the x axis and the relative distance L. Fig. 7 shows the relationship between the maximum value of the velocity in the negative direction of the x axis and the relative distance L. The operator can operate the attachment 30 at a speed equal to or lower than the maximum value in the x direction. As shown in Figs. 6 and 7, the smaller the relative distance L, the smaller the maximum value of the velocity in the x direction. In this way, the attachment 30 can be stopped gradually by restricting the operation of the attachment 30 closer to the entry prohibition surface 72. This makes it possible to suppress the occurrence of the cylinder 40 being jammed due to the attachment 30 being suddenly decelerated or stopped. In this embodiment, the smaller the relative distance L, the smaller the maximum value of the velocity in the x direction, but such a restriction does not have to be set.

[0050] Here, even if the relative distance L becomes zero, the maximum value of the speed in the x direction does not become zero. In other words, the controller (movement restriction means) 11 allows the bucket 33 to move along the entry restriction surface 72 when the movement of the attachment 30 is restricted. This makes it possible to move the bucket 33 along the entry restriction surface 72 even when the movement of the attachment 30 is restricted. Therefore, for example, the bucket 33 can be moved toward the control start position.

[0051] The relationship between the relative distance L and the maximum value of the rotation speed of the upper rotating body 22 is the same as the relationship shown in FIG. 6 and FIG. 7. If the right rotation of the upper rotating body 22 is the positive direction and the left rotation of the upper rotating body 22 is the negative direction, the relationship between the maximum value of the rotation speed in the positive direction and the relative distance L is as shown in FIG. 6, and the relationship between the maximum value of the rotation speed in the negative direction and the relative distance L is as shown in FIG. 7. The smaller the relative distance L, the smaller the maximum value of the rotation speed. In this way, the attachment 30 can be stopped more gently by restricting the operation of the attachment 30 closer to the entry prohibition surface 72. This makes it possible to suppress the occurrence of the cylinder 40 being jammed due to the attachment 30 being suddenly decelerated or stopped. In this embodiment, the smaller the relative distance L, the smaller the maximum value of the rotation speed, but such a restriction does not have to be set.

[0052] Here, even if the relative distance L becomes zero, the maximum value of the rotation speed does not become zero. In other words, the controller (movement restriction means) 11 allows the upper rotating body 22 to rotate when the movement of the attachment 30 is restricted. This makes it possible to rotate the upper rotating body 22 even when the movement of the attachment 30 is restricted. Therefore, for example, it is possible to move the bucket 33 toward the control start position. Also, by rotating the upper rotating body 22, it is possible to prevent the bucket 33 from contacting the target construction surface 71.

[0053] 8 shows a top view of the work machine 1 and the entry-prohibited surface 72. In the manual operation mode, when the operation of the attachment 30 is restricted, the controller (movement restriction means) 11 releases the restriction on the operation of the attachment 30 if the bucket 33 moves out of the range facing the entry-prohibited surface 72. Here, the direction in which the range facing the entry-prohibited surface 72 faces the entry-prohibited surface 72 may be the up-down direction or a direction perpendicular to the entry-prohibited surface 72.

[0054] For example, by rotating the upper rotating body 22 or traveling the lower traveling body 21, the bucket 33 may move out of the range facing the no-entry surface 72. Also, by moving the bucket 33 closer to the upper rotating body 22 or moving the bucket 33 away from the upper rotating body 22, the bucket 33 may move out of the range facing the no-entry surface 72. And, outside the range facing the no-entry surface 72, work such as leveling the ground or moving embankments may be performed. Therefore, by releasing the restriction on the operation of the attachment 30 outside the range facing the no-entry surface 72, these works can be preferably performed.

[0055] In the manual operation mode, when the restriction on the operation of the attachment 30 is released and the bucket 33 enters a range facing the forbidden entry surface 72, the controller (movement restriction means) 11 again restricts the operation of the attachment 30. This makes it possible to prevent the bucket 33 facing the forbidden entry surface 72 from hitting the target construction surface 71. When restricting the operation of the attachment 30 again, the controller (movement restriction means) 11 may notify the operator that the bucket 33 has entered a range facing the forbidden entry surface 72 by displaying the information on a display provided in the cab 23, by sound from a speaker, or by vibrating the operating lever 29.

[0056] As shown in FIG. 2, the work machine 1 has an operation limit changeover switch 27. The operation limit changeover switch 27 is provided in the cab 23. The controller (switching means) 11 switches between enabling and disabling the restriction on the operation of the attachment 30 by itself, depending on whether the operation limit on the attachment 30 is enabled or disabled. A display provided in the cab 23 shows whether the restriction on the operation of the attachment 30 is enabled or disabled. This allows the operator to know whether the restriction on the operation of the attachment 30 is enabled or disabled. The operator may be notified of whether the restriction on the operation of the attachment 30 is enabled or disabled by a sound from a speaker provided in the cab 23, vibration of the operation lever 29, or the like.

[0057] There are cases where work other than the work of operating the attachment 30 so that the construction surface 73 approaches the target construction surface 71 (work under semi-automatic control) is performed near the construction surface 73. For example, work such as piling up soil on the construction surface 73 and refilling the construction surface 73 is performed. Therefore, for example, when work other than the work of operating the attachment 30 so that the construction surface 73 approaches the target construction surface 71 is performed, such work can be preferably performed by disabling the restrictions on the operation of the attachment 30.

[0058] 2, the work machine 1 has an input device 28. The input device 28 is, for example, a touch panel, and is provided inside the cab 23. The operator can input the distance between the target construction surface 71 and the no-entry surface 72 into the input device 28. The controller (distance setting means) 11 sets the distance between the target construction surface 71 and the no-entry surface 72 in response to the operator's operation of the input device 28.

[0059] For example, the distance between the target construction surface 71 and the no-entry surface 72 is set by arranging the no-entry surface 72 at a position above the target construction surface 71 by the distance (mm) input to the input device 28. The distance between the target construction surface 71 and the no-entry surface 72 is set by arranging the no-entry surface 72 at the current tip position of the bucket 33. The distance between the target construction surface 71 and the no-entry surface 72 is set by arranging the no-entry surface 72 at the tip position of the bucket 33 when the restriction on the operation of the attachment 30 is switched to be enabled. The distance between the target construction surface 71 and the no-entry surface 72 is set by arranging the no-entry surface 72 at a position input to the input device 28, such as a line traced by a finger on a touch panel.

[0060] In the work machine 1, the bucket 33 is replaced depending on the application. The amount of variation in the position of the bucket 33 that occurs when semi-automatic control of the operation of the attachment 30 is started varies depending on the mass and shape of the bucket 33. Therefore, for example, the operator sets the distance between the target construction surface 71 and the no-entry surface 72 depending on the type of bucket 33 used. In this case, when semi-automatic control of the operation of the attachment 30 is started, it is possible to prevent the bucket 33 from hitting the target construction surface 71 even if the attachment 30 behaves differently from the target behavior.

[0061] The controller (distance setting means) 11 may automatically set the distance between the target construction surface 71 and the no-entry surface 72 in accordance with the type of bucket 33 attached to the arm 32. Information on the type of bucket 33 attached to the arm 32 may be input to the input device 28 by an operator, or may be acquired automatically.

[0062] The operator can also input the range (coordinates, etc.) of the no-entry surface 72 into the input device 28. The controller (range setting means) 11 sets the range of the no-entry surface 72 in response to the operator's operation of the input device 28. The range of the no-entry surface 72 may also be set by teaching. In teaching, the bucket 33 is manually positioned at two or more positions on the construction surface 73. The toe positions of the bucket 33 at this time are each registered in the storage device 13, thereby defining the range of the no-entry surface 72. The range of the no-entry surface 72 may also be set based on the rotation angle of the upper rotating body 22 and the reachable range of the attachment 30.

[0063] For example, as shown in Fig. 3, when a forbidden surface 72 is set on a two-dimensional cross section, the forbidden surface 72 will have an infinite length in the direction perpendicular to the cross section. Therefore, by setting the range of the forbidden surface 72, it is possible to prevent the forbidden surface from becoming excessively wide.

[0064] Note that the range of the no-entry surface 72 may be set to a default range before input to the input device 28. The default range is set in front of the upper rotating body 22, for example, based on the rotation angle of the upper rotating body 22 and the reachable range of the attachment 30. In this case, the operator may widen or narrow the default range by input to the input device 28.

[0065] (effect) As described above, according to the work machine 1 of this embodiment, as shown in FIG. 3, when the operation of the operation lever 29 is a predetermined operation, the operation of the attachment 30 is semi-automatically or automatically controlled so that the construction surface 73 constructed by the bucket 33 approaches the preset target construction surface 71. On the other hand, as shown in FIG. 4, when the operation of the attachment 30 is not controlled, the operation of the attachment 30 is restricted so that the bucket 33 does not intrude into the target construction surface 71 side of the entry prohibited surface 72. Before the operation of the attachment 30 is controlled, the bucket 33 may be moved to, for example, a control start position near the entry prohibited surface 72. At this time, the operation of the attachment 30 is restricted so that the bucket 33 does not intrude into the target construction surface 71 side of the entry prohibited surface 72, so that the target construction surface 71 and the bucket 33 are separated from each other. Therefore, when control of the operation of the attachment 30 is started in this state, even if the attachment 30 behaves differently from the desired behavior (such as the bucket 33 dropping slightly), it is possible to prevent the bucket 33 from hitting the target construction surface 71. This makes it possible to prevent the bucket 33 from digging too deep beyond the target construction surface 71. Also, before the operation of the attachment 30 is controlled, for example, the bucket 33 may move toward the no-entry surface 72 due to an erroneous operation. In this case as well, the operation of the attachment 30 is restricted so that the bucket 33 does not enter the target construction surface 71 side beyond the no-entry surface 72, so it is possible to prevent the bucket 33 from hitting the target construction surface 71.

[0066] Also, as shown in Figs. 5 to 7, the closer the bucket 33 is to the no-entry surface 72, the more the operation of the attachment 30 is restricted. For example, the closer the bucket 33 is to the no-entry surface 72, the more the operation speed of the attachment 30 is restricted. If the attachment 30 is suddenly decelerated or stopped near the no-entry surface 72, the machine body 24 may swing or the cylinder 40 may be compressed. If control of the operation of the attachment 30 is started in this state, the attachment 30 may behave differently from the target behavior (e.g., the bucket 33 may slightly drop). Therefore, the closer the bucket 33 is to the no-entry surface 72, the more the operation of the attachment 30 is restricted. This makes it possible to prevent the attachment 30 from behaving differently from the target behavior when control of the operation of the attachment 30 is started thereafter.

[0067] 5 to 7, the closer the bucket 33 is to the no-entry surface 72, the more the movement speed of the attachment 30 is limited. By limiting the movement speed of the attachment 30 as the bucket 33 approaches the no-entry surface 72, it is possible to prevent the attachment 30 from behaving differently from the target behavior when control of the attachment 30 operation is started thereafter.

[0068] 6 and 7, when the operation of the attachment 30 is restricted, the bucket 33 is permitted to move along the no-entry surface 72. This makes it possible to move the bucket 33 along the no-entry surface 72 even when the operation of the attachment 30 is restricted. Therefore, for example, the bucket 33 can be moved toward the control start position.

[0069] 8, when the operation of the attachment 30 is restricted, if the bucket 33 moves out of the range facing the forbidden surface 72, the restriction on the operation of the attachment 30 is released. Outside the range facing the forbidden surface 72, work such as leveling the ground or moving embankments may be performed. By releasing the restriction on the operation of the attachment 30 outside the range facing the forbidden surface 72, these works can be preferably performed.

[0070] 8, when the restriction on the operation of the attachment 30 is released, if the bucket 33 enters a range facing the no-entry surface 72, the operation of the attachment 30 is restricted again. This makes it possible to prevent the bucket 33 facing the no-entry surface 72 from hitting the target construction surface 71.

[0071] In addition, the operation restriction changeover switch 27 and the controller 11 switch between enabled and disabled restrictions on the operation of the attachment 30. There are cases where an operation other than an operation (operation by control) of operating the attachment 30 so that the construction surface 73 approaches the target construction surface 71 is performed near the construction surface 73. For example, there are cases where an operation such as piling up soil on the construction surface 73 and refilling the construction surface 73 is performed. Therefore, by disabling the restrictions on the operation of the attachment 30, such an operation can be preferably performed when an operation other than an operation of operating the attachment 30 so that the construction surface 73 approaches the target construction surface 71 is performed.

[0072] Also, the distance between the target construction surface 71 and the no-entry surface 72 is set according to the operation of the operator. In the work machine 1, the bucket 33 is replaced according to the application. The amount of variation in the position of the bucket 33 that occurs when control of the operation of the attachment 30 is started varies depending on the mass and shape of the bucket 33. Therefore, for example, the operator sets the distance between the target construction surface 71 and the no-entry surface 72 according to the type of bucket 33 used. In this case, even if the attachment 30 behaves differently from the target behavior when control of the operation of the attachment 30 is started, it is possible to prevent the bucket 33 from hitting the target construction surface 71.

[0073] In addition, the range of the entry-prohibited surface 72 is set. For example, if the entry-prohibited surface 72 is set on a two-dimensional cross section, the entry-prohibited surface 72 will have an infinite length in the direction perpendicular to the cross section. Therefore, by setting the range of the entry-prohibited surface 72, it is possible to prevent the entry-prohibited surface 72 from becoming excessively wide.

[0074] Although the embodiments of the present invention have been described above, they are merely illustrative examples and do not limit the present invention, and the specific configurations and the like can be appropriately modified in design. Furthermore, the actions and effects described in the embodiments of the invention are merely a list of the most preferable actions and effects resulting from the present invention, and the actions and effects of the present invention are not limited to those described in the embodiments of the present invention.

[0075] For example, when the operation lever 29 is operated in a predetermined manner in the MC mode, the bucket 33 can intrude into the target construction surface 71 side of the no-entry surface 72, but when the controller 11 detects a state in which the responsiveness of the work machine 1 is poor (for example, a state in which the temperature of the hydraulic oil is low), the operation of the attachment 30 may be restricted so that the bucket 33 does not intrude into the target construction surface 71 side of the no-entry surface 72. This makes it possible to prevent the attachment 30 from behaving differently from the target behavior, thereby stabilizing the construction accuracy. [Explanation of symbols]

[0076] 1. Work Machinery 11 Controller (control means, setting means, operation limiting means, switching means, distance setting means, range setting means) 13 Storage device 21 Undercarriage 22 Upper rotating body 23 Cab 24 Machine body 25 Swivel 27 Operation limit switch 28 Input Devices 29 Operating lever (operating means) 30 Attachment 31 Boom 32 Arm 33 Bucket (tip attachment) 34 Link member 40 Cylinder 41 Boom cylinder 42 Arm Cylinder 43 Bucket Cylinder 52 Angle Sensor 60 Inclination Sensor 61 Boom tilt angle sensor 62 Arm inclination angle sensor 63 Bucket tilt angle sensor 71 Target construction aspect 72 No entry surface 73 Construction side

Claims

1. The machine body, An attachment provided on the machine body and having a tip attachment; An operating means for operating the attachment; A control means for semi-automatically or automatically controlling the operation of the attachment when the operation means is a predetermined operation so that the construction surface constructed by the tip attachment approaches a preset target construction surface; A setting means for setting a no-entry surface at a position away from the target construction surface in a direction opposite to a direction in which the construction surface approaches the target construction surface; An operation limiting means for limiting the operation of the attachment so that the end attachment does not enter the target construction surface side of the no-entry surface when the control means is not controlling the operation of the attachment; A work machine comprising:

2. 2. The work machine according to claim 1, wherein the movement limiting means limits the movement of the attachment as the end attachment approaches the no-entry surface.

3. 3. The work machine according to claim 2, wherein the movement limiting means limits the movement speed of the attachment as the end attachment approaches the no-entry surface.

4. 2. The work machine according to claim 1, wherein the movement restricting means permits the end attachment to move along the no-entry surface when restricting the movement of the attachment.

5. The work machine according to any one of claims 1 to 4, characterized in that the operation limiting means releases the restriction on the operation of the attachment when the tip attachment moves out of the range facing the no-entry surface while the operation of the attachment is restricted.

6. The work machine according to claim 5, characterized in that the operation limiting means again limits the operation of the attachment when the tip attachment enters a range facing the no-entry surface while the restriction on the operation of the attachment is released.

7. 5. The work machine according to claim 1, further comprising a switching means for switching between enabling and disabling the restriction on the movement of the attachment by the movement restricting means.

8. 5. The work machine according to claim 1, further comprising a distance setting means for setting the distance between the target construction surface and the no-entry surface in response to an operation by an operator.

9. A work machine according to any one of claims 1 to 4, further comprising a range setting means for setting the range of the no-entry surface.

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