JP2019167745A - Work machine - Google Patents

Abstract

To provide a work machine which can display behavior in coming to inversion and fall early and in which an operator can recognize possibility of inversion and fall based on the display and can immediately cope with them.SOLUTION: On a grounding surface of left and right crawlers 3 of a hydraulic shovel 1, pressure sensors 18 are arranged side by side respectively in arrays a to d in a lateral direction and arrays one to five in a longitudinal direction, to detect ground contact pressure, and distribution of the ground contact pressures are displayed on a display 16. For example, when ground surface is sloped, the hydraulic shovel 1 is sloped toward one side and comes to inversion, and when ground surface collapses, the hydraulic shovel 1 is sloped toward one side and comes to fall. However, since distribution of the ground contact pressures of the crawlers 3 is changed prior to posture change, an operator can immediately recognize possibility of inversion and fall of the hydraulic shovel 1.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a work machine.

  As a work machine used for construction work, dismantling work, civil engineering work, etc., an upper swinging body is provided on the lower traveling body so as to be able to turn freely, and an articulated work front can be moved up and down at the front of the upper turning body. Attached is known. The work front is constructed by connecting a boom, an arm, and a work tool (bucket, breaker, etc.) to the upper swing body via a joint. During the above construction, the work front is moved forward from the upper swing body. Since the work is carried out while projecting and various postures are changed, if an unreasonable operation is performed, the posture of the work machine may become unstable and fall down.

  Therefore, for example, in the overturn warning device for a hydraulic excavator described in Patent Document 1, the tilt angle of the upper swing body detected by the tilt angle sensor, the rotation angles of the boom, arm, and bucket detected by the angle sensor, the acceleration sensor Reflects the static and dynamic balance of the hydraulic excavator based on the detection information such as the lower traveling body, upper revolving body, boom and arm acceleration detected by, the external force to the bucket tip detected by the pin force sensor ZMP (Zero Moment Point) coordinates are obtained as the action point on the ground surface.

  Based on the positional relationship of the ZMP coordinates with the support polygon that connects the grounding point between the excavator and the ground, for example, when the ZMP coordinate is located near the outline of the support polygon, the excavator may fall over. As a warning to the operator.

Japanese Patent No. 5491516

  In the technique of Patent Document 1 described above, ZMP coordinates are obtained reflecting not only static balance of a hydraulic excavator but also dynamic balance. For this reason, not only when the excavator changes its posture, but also when the excavator's operation changes suddenly, for example, when the upper revolving structure or the work front suddenly accelerates or decelerates, the reaction force received by the excavator due to these operations is not Prior to the movement, it is reflected in the ZMP coordinates, and a warning is given to the operator when the possibility of a fall occurs.

  However, the technique of Patent Document 1 is a technique for determining a fall based on the posture change and operation of the hydraulic excavator. For this reason, it is necessary to cause a change in the posture or operation of the hydraulic excavator, which causes a fall, and as a result, it is not possible to make a fall decision unless it is just before the hydraulic excavator actually falls. When there is a possibility of the hydraulic excavator to fall, it is necessary to operate the excavator in a stable direction to avoid the fall, but it is difficult to avoid early warning in this way, so if the operation is delayed and the fall cannot be avoided was there.

  In addition to falling, for example, on a slope with unstable scaffolding, there is a possibility that the hydraulic excavator may fall to the valley side, and in order to escape from the operator's cab to the outside at that time, a prior fall warning is required. ing. However, the fall determination is more difficult than the fall determination for the technique of Patent Document 1, and even if the ground collapse on the valley side that causes the fall occurs, the posture of the excavator does not change immediately. And when the excavator actually starts to fall due to the collapse of the ground, a fall warning is finally given due to the posture change, so there is almost no time for the operator to escape to the outside, an earlier fall warning Was requested.

  The present invention has been made to solve such problems, and the object of the present invention is to display the behavior at the time of falling or falling quickly, and the operator can fall or fall based on this display. The object is to provide a work machine that can recognize the sex and deal with it quickly.

  In order to achieve the above object, the working machine of the present invention is provided with a revolving upper revolving body on a lower traveling body having a pair of crawlers, and an articulated type at the front of the upper revolving body. In a work machine provided with a work front, the pair of crawlers detects a plurality of ground pressures at a plurality of locations with respect to the ground, and the pair of ground pressure detection units based on detection values from the plurality of ground pressure detection units. A controller that calculates a distribution of the contact pressure of the crawler and a contact pressure distribution display unit that displays the distribution of the contact pressure calculated by the controller are provided.

  According to the work machine of the present invention, the behavior at the time of falling or falling can be displayed at an early stage, and the operator can recognize the possibility of falling or falling based on this display and can quickly cope with it.

It is a side view showing a hydraulic excavator of an embodiment. It is a control block diagram which shows the structure of the behavior prediction display apparatus mounted in the hydraulic shovel. It is a perspective view which shows the support structure of the lower guide roller of the crawler on the left side. It is explanatory drawing which shows the change condition of the ground pressure at the time of a hydraulic excavator falling. It is explanatory drawing which shows the change state of distribution of the contact pressure when a hydraulic shovel falls. It is explanatory drawing corresponding to FIG. 5 which shows another example of the collapse situation of a ground. It is a flowchart which shows the contact pressure distribution display routine which a controller performs. It is explanatory drawing which shows a display display when possibility that it will fall to a hydraulic excavator arises. It is explanatory drawing which shows a display display when possibility that it will fall to a hydraulic shovel arises. It is a flowchart which shows the fall determination routine which a controller performs. It is a flowchart which shows the fall determination routine which a controller performs.

Hereinafter, an embodiment in which the present invention is embodied in a hydraulic excavator will be described.
FIG. 1 is a side view showing a hydraulic excavator according to the present embodiment. First, a schematic configuration of the hydraulic excavator will be described with reference to FIG.

  The lower traveling body 2 of the hydraulic excavator 1 is provided with a pair of left and right crawlers 3. The crawler 3 is driven by a traveling hydraulic motor (not shown) to cause the hydraulic excavator 1 to travel. An upper swing body 4 is provided on the lower traveling body 2, and the upper swing body 4 is driven to swing by a swing hydraulic motor (not shown). An articulated work front 5 is provided at the front part of the upper swing body 4, and the work front 5 includes a boom 6, an arm 7, and a bucket 8. The angle of the boom 6 is changed by the boom cylinder 6a, the angle of the arm 7 is changed by the arm cylinder 7a, and the angle of the bucket 8 is changed by the bucket cylinder 8a.

  A driver's cab 10 in which an operator is boarded is provided in the front part of the upper swing body 4 on the frame 9, and a fuel tank 11, a machine room 12, a counterweight 13, and the like are provided on the rear side of the driver cab 10 on the frame 9. It has been. Although not shown, an engine is mounted in the machine room 12, and the above-described traveling or turning hydraulic motor and the cylinders 6a to 8a are operated by supplying hydraulic oil from a hydraulic pump driven by the engine.

  FIG. 2 is a control block diagram showing the configuration of the behavior prediction display device mounted on the hydraulic excavator. The controller 15 of the behavior prediction display device shown in the figure performs prediction / display processing regarding the overturning and falling of the hydraulic excavator 1, and the display 16 (ground pressure correlation value distribution display unit) and the speaker 17 appropriately according to the prediction result. A warning is made to the operator.

  For example, when the ground where the excavator 1 is located is inclined, the center of gravity of the excavator 1 is moved by the operation of the work front 5 or the upper swing body 4, or the moving excavator 1 is moving. Occurs when it reaches the soft ground. The fall of the excavator 1 occurs, for example, when the ground on the valley side collapses during work on a slope or during movement. In either case, the excavator 1 eventually tilts toward one side and falls or falls, but the distribution of the contact pressure of the crawler 3 changes prior to the change in the posture.

  That is, the distribution of the contact pressure of the crawler 3 is substantially equal when the excavator 1 is located on a flat ground, whereas the excavator 1 is inclined and falls due to the above factors. When the possibility of falling occurs, the distribution of the contact pressure is biased prior to the posture change due to the inclination. In addition, the distribution of the contact pressure also reflects the operating conditions of the work front 5 and the upper swing body 4 that greatly affect the overturning of the excavator 1. In view of this, the present invention is one in which a fall or fall is predicted quickly based on the distribution of the contact pressure of the crawler 3, and the details thereof will be described below.

  In order to detect the distribution of the ground pressure of the left and right crawlers 3, each crawler 3 is provided with a number of strain gauge pressure sensors 18 (ground pressure correlation value detection units). In FIG. 2, the detection points of the contact pressure by these pressure sensors 18 are schematically shown on the contact surfaces of the left and right crawlers 3 in plan view, and the detection points are in the front-rear direction (in the present invention). It is distributed in a total of 10 locations, 5 locations at regular intervals (corresponding to the crawler traveling direction) and 2 locations in the left-right direction (corresponding to the direction orthogonal to the crawler traveling direction of the present invention). Hereinafter, for convenience of explanation, detection points in the front-rear direction are referred to as 1 to 5 rows in order from the front side to the rear side, and detection points in the left-right direction are referred to as rows a to d in order from the left side to the right side.

Next, a specific installation structure of the pressure sensor 18 will be described together with the configurations of the left and right crawlers 3.
As shown in FIG. 1, the left and right crawlers 3 are laid so as to circulate in a predetermined ring shape with the support of a large number of rollers. Each roller is arranged between an activation roller 21 for transmitting the driving force of the traveling hydraulic motor to the crawler 3, an idler roller 20 for applying tension to the crawler 3, and between the activation roller 21 and the idler roller 20. It consists of a large number of guide rollers 22 that guide the circulation of three. The ground contact surface of the crawler 3 with respect to the ground is maintained in a substantially planar shape by a total of nine guide rollers 22 (hereinafter referred to as lower guide rollers) arranged side by side with the starting roller 21 and the idle roller 20. Yes.

FIG. 3 is a perspective view showing a support structure of the lower guide roller 22 of the left crawler 3. The right lower guide roller 22 has the same symmetrical structure, and therefore the left support structure will be described as a representative.
Brackets 24 are provided at a predetermined interval in the front-rear direction on the left side surface 2 a of the lower traveling body 2, and a pair of left and right support frames 25 extending in the front-rear direction are supported by these brackets 24. Each lower guide roller 22 is disposed between the left and right support frames 25 and is rotatably supported on both left and right sides by a bearing member 26 fixed to the lower surface of each support frame 25, thereby guiding the circulation of the crawler 3. It is supposed to be. Although not shown, the starting roller 21 and the idler roller 20 are also pivotally supported by the support frame 25, and these pivotal support portions are concealed from the side by a cover 27 shown in FIG.

  The above-described pressure sensors 18 are disposed on the left and right sides of a total of five lower guide rollers 22 in the front and rear, out of a total of nine lower guide rollers 22, and are fixed on the support frame 25 with bolts 28. Has been. The weight of the hydraulic excavator 1 acts on the ground via the crawler 3, and the reaction force acts on the ground contact surface of the crawler 3 as a ground pressure. Accordingly, the contact pressure acting on the crawler 3 is received by the support frame 25 via the rollers 20 to 22, and the support frame 25 correlates with the magnitude of the contact pressure acting directly below the rollers 20 to 22. Distortion occurs, and this distortion is detected by the pressure sensor 18 as a ground pressure.

  The pressure sensor 18 located on the left side of each lower guide roller 22 mainly detects the ground pressure on the left side of the crawler 3, and the pressure sensor 18 located on the right side of each lower guide roller 22 mainly detects the ground pressure on the right side of the crawler 3. As a result, as described with reference to FIG. 2, the detection points are arranged in the crawler 3 at five equal intervals in the front-rear direction and at two positions in the left-right direction.

Next, prediction / display processing related to the actual fall and fall of the hydraulic excavator 1 by the controller 15 will be described. Prior to that, the change in the ground pressure of the crawler 3 that occurs when the excavator 1 falls and falls. State.
FIG. 4 is an explanatory view showing a change state of the ground pressure when the excavator 1 falls over. The fall of the excavator 1 is limited to the left and right or the front-rear direction. For example, even if the ground is inclined to the right rear, it cannot fall in an oblique direction following the inclination, and is more strongly affected by the inclination. Fall down to the left or right or back and forth. For this reason, in FIG. 4, the situation that leads to a fall to the right (indicated by (b) and (c) in the figure) and the situation that leads to a fall to the rear (indicated by (d) and (e) in the figure) ).

  First, as shown in FIG. 4 (a), when the excavator 1 is located on a flat ground, the ground pressures in rows a to d in the left-right direction (average values of rows 1 to 5, respectively, and so on) Are substantially the same, and similarly, the ground pressures in the 1st to 5th rows in the front-rear direction (average values of the ae rows, respectively) are almost equal. Therefore, there is no possibility that the excavator 1 will fall or fall, and the distribution of the contact pressure at this time is referred to as a normal pattern.

  As shown in FIG. 4B, for example, when the ground is inclined to the right, the distribution of contact pressure in the left and right rows a to d is stepwise from row a to row d. There is an increasing bias, and there is a gap between all adjacent ground pressures. This situation means that there is a possibility that the excavator 1 tilts to the right and falls, and if the slope to the right becomes sharp as shown in FIG. The bias becomes stronger and falls to the right.

The ground inclination in the front-rear direction is basically the same, and as shown in FIG. 4D, for example, when the ground is inclined backward, the distribution of the ground pressure in the first to fifth rows in the front-rear direction. There is a bias that gradually increases from the first row to the fifth row, and there is a disparity in all adjacent ground pressures. This situation means that there is a possibility that the excavator 1 tilts backward and falls, and as shown in FIG. Strengthens and falls backwards.
Hereinafter, the distribution of the contact pressure when a bias that may lead to overturning as shown in FIGS. 4B and 4D occurs is referred to as the overturning pattern. In the overturning pattern, the excavator 1 is moved in a stable direction. It is necessary to take measures such as operation.

  Even when the ground is tilted in any direction, left and right and front and rear, the distribution of the contact pressure has a falling pattern ahead of the actual change in the posture of the hydraulic excavator 1 due to the tilt as described above. Move to the equivalent. For this reason, for example, as will be described later, if the deviations ΔPad and ΔP15 between the current maximum and minimum values of the contact pressure are compared with preset fall determination values ΔPad0 and ΔP150, the distribution of the contact pressure corresponds to the fall pattern. It can be predicted whether or not the excavator 1 will fall over. As a result, it is possible to predict a rightward fall shown in FIG. 4C at an early time point when the fall pattern shown in FIG. 4B is reached, and an early time point when the fall pattern shown in FIG. Thus, it is possible to predict the backward fall shown in (e).

  On the other hand, FIG. 5 is an explanatory view showing a change state of the distribution of the contact pressure when the excavator 1 falls. The fall of the excavator 1 can occur in any direction of 360 ° corresponding to the direction of the ground collapse. For this reason, FIG. 5 illustrates a situation in which a collapse has occurred in the right rear of the excavator 1 and a possibility of a fall to the right rear has occurred. 5A shows the relationship between the left and right crawlers 3 and the collapsed area in a plan view similar to that in FIG. 4, and along the boundary line between the flat land and the collapsed area (hereinafter referred to as the collapsed boundary line Lbodr). The relationship between the crawler 3 and the collapse area in a side view is also shown.

  As shown in FIG. 5A, when a collapse occurs on the right rear side of the excavator 1, a ground contact pressure of almost 0 is detected at a detection point on the right rear side of the collapse boundary line Lbodr, which is smaller than the collapse boundary line Lbodr. At the left front detection point, a contact pressure larger than the average contact pressure corresponding to the flat ground is detected. This is because the weight of the hydraulic excavator 1 that is no longer supported due to the collapse of the ground is added to the area on the left front side of the collapse boundary Lbodr.

  As a result, in the direction perpendicular to the collapse boundary line Lbodr, the contact pressure at each detection point is a first group having a difference with the collapse boundary line Lbodr as a boundary (almost 0, corresponding to the small side of the present invention). And the second group (which is larger than the average contact pressure equivalent to the flat ground and corresponds to the large side of the present invention). As the number of contact pressures included in the first group increases, the possibility of the hydraulic excavator 1 falling due to collapse increases, and if the collapse area further expands as shown in FIG. To. Hereinafter, as shown in FIG. 5A, the distribution of the contact pressure when a bias that may result in a fall occurs is referred to as a fall pattern. In the fall pattern, the operator escapes from the cab 10 to the outside. It is necessary to deal with.

  Thus, prior to the change in the posture of the hydraulic excavator 1 due to the collapse of the ground, the distribution of the ground pressure shifts to that corresponding to the falling pattern. Therefore, for example, as will be described later, if the number N of current contact pressures included in the first group (or the number of contact pressures included in the second group) is compared with a predetermined determination value N, the contact pressure It can be predicted whether the distribution corresponds to a fall pattern, that is, whether the excavator 1 will fall. As a result, when moving to the falling pattern shown in FIG. 5A, it is possible to predict the falling rightward shown in FIG.

  The ground collapse situation is not limited to FIG. 5A, and may occur in the form shown in FIG. 6, for example. In this case, although a clear collapsing boundary line Lbodr cannot be specified, it is common in that the ground pressure at each detection point can be classified into the first group and the second group having a difference, and the hydraulic pressure can be determined from the number of any ground pressure. There is no difference in that the excavator 1 can be predicted to fall.

  The controller 15 determines whether the excavator 1 has fallen or fallen on the premise of the ground pressure change state of the crawler 3 that occurs prior to the fall and fall. For this determination process, the controller 15 executes a ground pressure distribution display routine shown in FIG. 7 at predetermined control intervals while the excavator 1 is in operation.

  First, in step S1, detection information from each pressure sensor 18 is input, and in subsequent step S2, based on the detection information, the distribution of the ground pressure along the rows a to d and the ground pressure along the directions 1 to 5 are shown. , The distribution of the contact pressure is displayed on the display 16 corresponding to each detection point together with the contact surfaces of the left and right crawlers 3.

FIG. 8 is an explanatory view showing a display when the hydraulic excavator 1 is likely to fall, and FIG. 9 is an explanatory view showing a display when the hydraulic excavator 1 is likely to fall. In these figures, the ground pressure at each detection point is shown in shades on the left and right crawlers 3 and is displayed in white when the ground pressure is near 0, and the gradation is changed to the dark side as the ground pressure increases. Yes.
At the same time, the work front is also displayed on the display 16, and the angle is changed according to the turning of the upper turning body 4 as indicated by a virtual line. For this reason, the operator can easily grasp the distribution of the contact pressure on the left and right crawlers 3 regardless of the turning angle of the work front 5.

  For example, when the excavator 1 shown in FIG. 4A is located on a flat ground, the ground pressures in the rows a to d and the rows 1 to 5 are substantially equal. As shown in FIG. 9 (a), all detection points on the display 16 are displayed with an intermediate gradation corresponding to the average ground pressure. Based on this display, the operator can easily recognize that the excavator 1 is in a stable posture with no possibility of falling or falling.

  Further, although not so much as shifting to the falling pattern shown in FIGS. 4B and 4D, for example, when the ground is slightly inclined to the right (distribution in the distribution in the rows a to d). As shown in FIG. 8 (b), the display 16 is displayed so that the gray level of the detection point on the right side becomes higher. Similarly, when there is a slight backward inclination on the ground (biased in the distribution in the 1 to 5 column direction), as shown in FIG. The display 16 is displayed as follows.

Based on these displays, the operator can easily recognize the situation in which the posture of the hydraulic excavator 1 is somewhat unstable, although not to fall, and by operating the hydraulic excavator 1 while paying attention to the fall, It is possible to keep the excavator 1 stable by preventing the transition to FIGS. 4B and 4D corresponding to the falling pattern.
In addition, the cause of the instability of the excavator 1 is not limited to the inclination of the ground, but may also be caused by the movement of the center of gravity or the soft ground. In these cases, the display according to the ground pressure distribution is similarly displayed. Made.

  Further, although not so much as shifting to the falling pattern shown in FIG. 5A, for example, when the ground has collapsed at a part of the contact surface of the crawler 3, the falling area as shown in FIG. 9B. The display 16 is displayed so that the detected points are white. Based on this display, the operator can easily recognize the situation in which the excavator 1 is not stable enough to fall down, and operates the excavator 1 while paying attention to the fall. The corresponding shift to FIG. 5A can be prevented and the stability of the hydraulic excavator 1 can be maintained.

  As described above, the density of each detection point displayed on the display 16 indicates the distribution of the ground pressure, and hence the behavior when the excavator 1 falls or falls before the actual change in the posture of the excavator 1. To express. Therefore, the operator can quickly recognize the current possibility of the hydraulic excavator 1 toppling or falling based on these indications, and take appropriate measures according to each situation, in this case, driving operation to avoid the falling or falling. It can be implemented quickly and accurately.

On the other hand, after finishing the process of step S2, the controller 15 determines whether or not there is an indication of a fall pattern in the current distribution of the ground pressure of the crawler 3 in step S3, and in the subsequent step S4, the ground of the current crawler 3 is determined. It is determined whether there is a sign of a fall pattern in the pressure distribution.
The signs of the falling pattern are not only when the actual movement to the falling pattern is required and it is necessary to deal with the operation of the hydraulic excavator 1 in the stable direction, but also when there is a slight deviation from the previous normal pattern and no action is required. Including. For example, when the distribution of the contact pressure is uneven in the a to d row direction or the 1 to 5 row direction, even if the difference between the adjacent contact pressures is very small, it is considered that there is a sign of a fall pattern.

  Similarly, the sign of the fall pattern includes not only the case where the operator actually moves to the fall pattern and requires countermeasures such as escape to the outside of the operator, but also the case where no action is required due to a slight deviation from the previous normal pattern. . For example, if the distribution of the contact pressure can be classified into the first group and the second group having a disparity, it is considered that there is a sign of a fall pattern even if the disparity is small.

  As will be described below, when it is determined that the distribution of the contact pressure has shifted to the falling pattern, a warning process regarding the falling is performed, and when it is determined that the distribution has shifted to the falling pattern, a warning process regarding the falling is performed. The processing contents are different from the determination of the fall pattern and the determination of the fall pattern. Therefore, it is first determined in step S3, 4 which pattern is present.

  If the controller 15 makes a No (no) determination in step S3 as no falling pattern sign and makes a No determination in step S4 as no falling pattern sign, the controller 15 ends the routine. Therefore, in this case, the display of the ground pressure distribution on the display 16 is continued for the operator without executing the warning process of falling or falling.

On the other hand, when a Yes (positive) determination is made in step S3 because there is a sign of a fall pattern, a fall decision process is executed in step S5, and the controller 15 starts a fall decision routine shown in FIG.
First, in step S11, it is determined whether the sign of the falling pattern determined in step S3 in FIG. 7 is based on the bias of the contact pressure distribution in the a to d row directions or the 1 to 5 row directions. When it is based on the bias of the ground pressure distribution in the directions of rows a to d, the process proceeds to step S12, and a deviation ΔPad between the ground pressure in the rows a and the ground pressure in the rows d (both average values in rows 1 to 5) is calculated. To do. Since the ground pressures in rows a to d increase in one direction, one of the ground pressure in row a and the ground pressure in row d corresponds to the maximum value, and the other corresponds to the minimum value. In a succeeding step S13, it is determined whether or not the deviation ΔPad is equal to or larger than a predetermined determination deviation ΔPad0, and when it is No, the routine is ended.

  If it is determined in step S11 that the overturning pattern sign is based on a bias in the ground pressure distribution in the first to fifth rows, the process proceeds to step S14, where one row of ground pressure and five rows of ground pressure (both are Deviation ΔP15 from the average value of columns a to d) is calculated. Since each of the ground pressures in the first to fifth rows increases in one direction, one of the first row ground pressure and the fifth row ground pressure corresponds to the maximum value, and the other corresponds to the minimum value. In the subsequent step S15, it is determined whether or not the deviation ΔP15 is equal to or larger than a predetermined determination deviation ΔP150. If No, the routine is terminated.

  The deviation ΔPad is an index representing the ease with which the excavator 1 can be tilted to the left and right, and the determination deviation ΔPad0 functions as a threshold for determining the transition to the left-right direction falling pattern. Similarly, the deviation ΔP15 is an index indicating the ease of tipping of the hydraulic excavator 1 forward and backward, and the determination deviation ΔP150 functions as a threshold for determining the transition to the tipping pattern in the front-rear direction. Therefore, when the determination at step S13 is No and when the determination at step S15 is No, the excavator 1 has not shifted to the overturning pattern, and it can be considered that the operation in the stable direction by the operator is unnecessary. As the display, one of FIGS. 8B and 8D is continued.

  Further, when the determination in step S13 or step S15 is Yes, it means a transition to a fall pattern. Naturally, a display corresponding to the fall pattern of FIG. 8C or 8E is made by the process of step S2 in FIG. 7, and it can be considered that an operation in a stable direction by the operator is necessary to avoid the fall. . At this time, the controller 15 proceeds to step S16 to execute a fall warning process, and an arrow indicating a possible fall direction and a fall warning message are displayed on the display 16 as shown in FIG. 8C or 8E. Along with the display, the speaker 17 warns even by voice.

  Based on this overturn warning, the operator can recognize at an early stage that the hydraulic excavator 1 is likely to fall over, and therefore it is necessary to avoid the overturn, and the hydraulic excavator 1 can be prevented from overturning by appropriate measures. In particular, in this embodiment, not only a warning but also the direction of the overturn of the hydraulic excavator 1 is displayed on the display 16, so that the operator can be urged to perform an optimum operation for avoiding the overturn, thereby further ensuring the avoidance of the overturn. can do.

On the other hand, when it is determined Yes in step S4 in FIG. 7 because there is a sign of a fall pattern, the fall determination process is executed in step S6, and the controller 15 starts the fall determination routine shown in FIG.
First, in step S21, it is determined whether or not the number N of contact pressures included in the first group is a predetermined determination value N0 (first determination value), for example, 6 or more. The number N of contact pressures included in the first group is an index representing the size of the collapse region, and thus the possibility of subsequent fall of the hydraulic excavator 1, and the judgment value N0 functions as a threshold for judging the transition to the fall pattern. To do. For this reason, when the determination in step S21 is No, the excavator 1 has not shifted to the falling pattern, and it can be regarded that it is not necessary for the operator to escape to the outside. For example, FIG. 9B is continued as a display display. .

Further, when the determination in step S21 is Yes, it means a transition to a fall pattern. Naturally, a display corresponding to the fall pattern of FIG. 9C is made by the process of step S2 of FIG. 7, and it can be considered that the escape of the operator to the outside is necessary. At this time, the controller 15 proceeds to step S22 to execute a fall warning process, and as shown in FIG. 9C, an arrow indicating a possible fall direction and a fall warning message are displayed on the display 16, and The speaker 17 warns even by voice.
In step S21, instead of the number N of contact pressures included in the first group, for example, the number of contact pressures included in the second group falls when it is less than a predetermined determination value (second determination value). The warning process may be executed in step S22 on the assumption that the pattern has been shifted.

  Based on the fall warning, the operator can recognize the possibility of the fall of the hydraulic excavator 1 at an early stage, and can quickly escape from the cab 10 to the outside. In order to prevent the excavator 1 from getting caught in the fall, it is desirable to escape in the direction opposite to the fall direction. However, when the fall warning is given due to the collapse of the ground, the posture of the excavator 1 is still almost changed. The operator cannot determine the direction of the fall. However, in this embodiment, not only the warning but also the falling direction is displayed on the display 16, so that the operator can be prompted to escape in the safest direction, and the damage caused by the falling can be more reliably avoided. Can do.

  This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above-described embodiment, in addition to the process of displaying the distribution of the contact pressure of the crawler 3 on the display 16, the excavator 1 is turned over based on the contact pressure deviation ΔPad in the directions a to d or 1 to 5 rows. A warning was given to warn of the fall of the hydraulic excavator 1 based on the number N of ground pressures of the first group, and also warned about the direction of fall and the direction of fall. However, these warning processes are not necessarily executed, and the distribution of the ground pressure may be displayed on the display 16 only.

Moreover, in the said embodiment, although the pressure sensor 18 was arranged in parallel so that it might become a to d row | line | column in the left-right direction and 1-5 row in the front-back direction, the arrangement | positioning is not restricted to this, The number and arrangement | positioning in parallel arrangement You may change arbitrarily. In addition, for example, if only the fall or fall of the hydraulic excavator 1 in the left-right direction is predicted, the pressure sensor 18 may be provided in parallel only in the left-right direction. Similarly, the pressure sensor 18 may be juxtaposed only in the front-rear direction if only the fall or fall in the front-rear direction is predicted. In this case, the pressure sensor 18 is juxtaposed only in either the left or right crawler 3. May be.
Moreover, in the said embodiment, although the ground pressure of each detection point was represented with the shading on the display 16, the display form is not restricted to this, For example, you may represent with the number corresponding to the magnitude | size of a ground pressure.
Moreover, in the said embodiment, although distortion which generate | occur | produces in the support frame 25 was converted into the ground pressure, and it output from the pressure sensor 18, it does not necessarily need to convert into ground pressure. The contact pressure correlation value of the present invention means an index that changes with a predetermined correlation with respect to a change in the contact pressure, and may be other than the contact pressure as long as it satisfies this condition. The distortion itself is included in the ground pressure correlation value. Therefore, indicators other than the contact pressure and distortion of the support frame 25 may be output from the pressure sensor 18 and the distribution thereof may be calculated and displayed. Such an aspect is also included in the present invention.

1 Excavator (work machine)
2 Lower traveling body 3 Crawler 4 Upper turning body 5 Work front 15 Controller 16 Display (ground pressure correlation value distribution display section)
18 Pressure sensor (ground pressure correlation value detector)

Claims (7)

In a working machine in which a revolving upper revolving body is provided on a lower traveling body provided with a pair of crawlers, and an articulated work front is provided at a front portion of the upper revolving body,
A plurality of ground pressure correlation value detection units that respectively detect ground pressure correlation values at a plurality of locations with respect to the ground of the pair of crawlers;
A controller that calculates a distribution of ground pressure correlation values of the pair of crawlers based on detection values from the plurality of ground pressure correlation value detection units;
A working machine comprising: a ground pressure correlation value distribution display unit that displays a distribution of the ground pressure correlation value calculated by the controller. The plurality of contact pressure correlation value detection units are arranged in parallel in at least one of the traveling direction of the pair of crawlers or the direction orthogonal to the traveling direction,
The controller determines the possibility of falling or falling based on the distribution of the contact pressure correlation value along at least one of the traveling direction of the pair of crawlers or the direction orthogonal to the traveling direction, and falls or falls 2. The work machine according to claim 1, wherein a warning is displayed on the ground distribution display device when it is determined that there is a possibility of the failure.   In the controller, the ground pressure correlation values detected by the plurality of ground pressure correlation value detection units increase stepwise toward any one of the parallel arrangement directions of the plurality of ground pressure correlation value detection units, 3. The work machine according to claim 2, wherein when there is a difference in all adjacent ground pressure correlation values, it is determined that the work machine may be overturned.   The controller may be configured such that the ground pressure correlation values detected by the plurality of ground pressure correlation value detection units are different from each other in the direction in which the plurality of ground pressure correlation value detection units are arranged side by side. 3. The work machine according to claim 2, wherein when the work machine is classified into the first group and the second group, the work machine is determined to have a possibility of falling.   The controller may cause the work machine to fall when a deviation between a maximum value and a minimum value of the contact pressure correlation values detected by the plurality of contact pressure correlation value detection units is equal to or greater than a preset threshold value. The work machine according to claim 3, wherein the work machine is determined to be present.   The controller is configured such that the number of the ground pressure correlation value detection units corresponding to the ground pressure correlation value of the first group is equal to or greater than a preset first determination value, or the ground pressure correlation of the second group. 5. The method according to claim 4, wherein when the number of the contact pressure correlation value detection units corresponding to the value is less than a preset second determination value, it is determined that the work machine may fall. The working machine described.   In the controller, the ground pressure correlation values detected by the plurality of ground pressure correlation value detection units have a pressure difference with any one of the parallel arrangement directions of the plurality of ground pressure correlation value detection units as a boundary. When the number of the contact pressure correlation value detection units corresponding to the contact pressure correlation value of the first group is equal to or more than a preset first determination value, or the second group When the number of the contact pressure correlation value detection units corresponding to the contact pressure correlation value of the group is less than a preset second determination value, it is determined that the work machine may fall. The work machine according to claim 5.