JP2018003513A - Work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work machine with an area-limiting excavation control device for controlling movement of a work device so that the work device does not penetrate underneath a targeted excavation surface, the work device being made to reach the targeted excavation surface accurately and a control accuracy being ensured when shaping the targeted excavation surface through the area-limiting excavation control, regardless of whether a piping rupture control valve is provided.SOLUTION: An area-limiting excavation control device respectively stores in ROM35d two types of first and second correlation tables as first and second correlation tables, according to whether a piping rupture control valve is provided. An arm cylinder speed calculation unit 43a selects from the two types of first correlation tables a corresponding table according to the presence or absence of the piping rupture control valve, and calculates driving speed of the arm cylinder. A boom operation signal control value calculation unit 3c selects from the two types of second correlation tables a corresponding table according to the presence or absence of the piping rupture control valve, and calculates a control value for an operation signal of a flow amount control valve for the boom.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a work machine including an articulated work device such as a hydraulic excavator, and more particularly, a region-limited excavation control device that performs excavation by restricting movement of the work device so that the work device does not enter below a target excavation surface. It is related with the working machine provided with.

  A work machine equipped with an articulated work device such as a hydraulic excavator is provided with a region-limited excavation control device that performs excavation with restricted movement of the work device so that the work device does not enter below the target excavation surface. One example is described in Patent Document 1. According to this technology, the excavator work device can be controlled semi-automatically according to the operation of the operator, and the target excavation surface can be shaped. This control is called area limited excavation control.

  Also, in a working machine such as a hydraulic excavator, the hydraulic actuator is disposed between a hydraulic actuator such as a boom cylinder and a flow control valve, and the hydraulic actuator is operated when an abnormality such as a break of the hydraulic pipe or an oil leak occurs. Some have a pipe break control valve that stops the flow of pressure oil from the cylinder chamber on the load side (the side on which the weight of the driven body of the hydraulic actuator acts) and prevents the working device from falling, an example of which is patented It is described in Document 2.

Japanese Patent No. 3056254 Japanese Patent No. 5091034

  In a work machine having a pipe breakage control valve as described in Patent Document 2, in the operation on the side not holding the load (boom raising operation in the case of a boom), the pressure oil supplied to the bottom side of the boom cylinder is After the poppet valve body inside the poppet valve of the pipe breakage control valve is pushed up, pressure oil is supplied from the hydraulic pump via the flow rate control valve to the bottom side of the boom cylinder.

  In the operation for holding the load, the pilot pressure for lowering the boom acts on the spool of the pipe break control valve, and the poppet valve is opened accordingly, and the pressure oil on the bottom side of the boom cylinder is discharged to the tank.

  On the other hand, area limited excavation control as described in Patent Document 1 controls a work device using an operation signal generated by an operator's operation and posture information of the work device.

  The control device that performs the area limited excavation control uses the correlation table between the operation signal and the cylinder speed or the correlation table between the cylinder speed and the operation signal to calculate the cylinder speed for performing the area limited excavation control or to perform the operation for realizing the cylinder speed. A signal is calculated, and a command is output to an electromagnetic valve provided in the operation system so that the operation signal can be obtained.

  By the way, in a work machine equipped with a pipe break control valve, the poppet valve and the spool operate as described above. Therefore, the cylinder speed decreases even with the same operation signal as compared with a work machine not equipped with a pipe break control valve. The relationship between the signal and the cylinder speed or the relationship between the cylinder speed and the operation signal may change.

  Therefore, the region-limited excavation control device storing the correlation table between the operation signal and the cylinder speed or the correlation table between the cylinder speed and the operation signal created for the work machine having the pipe break control valve is not equipped with the pipe break control valve. When applied to a work machine, the desired cylinder speed cannot be obtained, and as a result, the control accuracy when shaping the target excavation surface deteriorates, and the work device enters below the target surface or is not sufficiently close to the target excavation surface. Such an event occurs. In the opposite case (an area limited excavation control device storing a correlation table between an operation signal and a cylinder speed or a correlation table between a cylinder speed and an operation signal created for a work machine not equipped with a pipe break control valve, In the same manner, the desired cylinder speed cannot be obtained, and as a result, the control accuracy when shaping the target excavation surface deteriorates, and the work device enters below the target excavation surface, or the target Events such as not being close enough to the excavation surface occur.

  The purpose of the present invention is a work machine equipped with a region-limited excavation control device that controls the movement of the work device so that the work device does not enter below the target excavation surface, regardless of whether a pipe breakage control valve is mounted, It is an object of the present invention to provide a work machine capable of ensuring control accuracy when shaping a target excavation surface by area limited excavation control.

  In order to solve the above-described problems, the present invention provides an articulated work device, a plurality of hydraulic cylinders that drive the work device, a plurality of operation devices that direct the operation of the work device, and the plurality of operations. In a working machine that is driven by a device operation signal and includes a plurality of flow control valves that control the flow of pressure oil supplied to the plurality of hydraulic cylinders, the work device does not enter below the target excavation surface. Whether or not a region-limited excavation control device to be controlled and a pipe breakage control valve connected to at least one of a plurality of hydraulic pipelines connecting the plurality of hydraulic cylinders and the plurality of flow rate control valves respectively are mounted An information setting device in which information is set, and the region-limited excavation control device receives each first signal from operation signals of at least some of the plurality of specific operation devices among the plurality of operation devices. A first calculation unit that calculates drive speeds of a plurality of hydraulic cylinders corresponding to the plurality of specific operating devices using a function, a drive speed of the plurality of hydraulic cylinders calculated by the first calculation unit, and the work Based on the positional relationship between the apparatus and the target excavation surface, a plurality of specific cylinders of at least some of a plurality of hydraulic cylinders that drive the work device so that the work device does not enter below the target excavation surface. A second calculation unit for calculating a control value of the hydraulic cylinder driving speed; and a plurality of the plurality of specific hydraulic cylinder driving speed control values calculated by the second calculation unit using the respective second correlation functions. Based on the control value of the operation signal of the plurality of operation devices calculated by the third calculation unit, a third calculation unit that calculates the control value of the operation signal of the plurality of operation devices corresponding to the specific hydraulic cylinder, Said An operation signal correction device that corrects operation signals of a plurality of operation devices corresponding to the plurality of specific hydraulic cylinders so that the industrial device does not enter below the target excavation surface, and the plurality of specific operation devices The plurality of corresponding hydraulic cylinders include a hydraulic cylinder related to the pipe breakage control valve, and the first calculation unit has a specific first correlation for the hydraulic cylinder related to the pipe breakage control valve as the first correlation function. The plurality of specific hydraulic cylinders include hydraulic cylinders related to the pipe breakage control valve, and the third calculation unit is configured to use as a second correlation function for the hydraulic cylinders related to the pipe breakage control valve. Including a specific second correlation function, wherein the first calculation unit and the third calculation unit receive information about whether or not the pipe breakage control valve is mounted from the information setting device, and the pipe breakage Compensating the arithmetic processing by the specific first correlation function and the specific second correlation function according to whether or not a control valve is mounted, the hydraulic cylinder drive speed related to the pipe break control valve and the pipe break control valve It is assumed that the control value of the operation signal of the operation device corresponding to the hydraulic cylinder concerned is calculated.

  In this way, in the first and third calculation units, information related to whether or not the pipe breakage control valve is mounted is input from the information setting device, and the specific first correlation function and the specific are determined according to whether or not the pipe breakage control valve is mounted. By correcting the calculation processing by the second correlation function, and calculating the control value of the operating signal of the operating device corresponding to the hydraulic cylinder driving speed related to the pipe break control valve and the hydraulic cylinder related to the pipe break control valve, Regardless of whether or not the pipe breakage control valve is mounted, it is possible to ensure the control accuracy when shaping the target excavation surface by the area limited excavation control.

  According to the present invention, it is possible to ensure the control accuracy when shaping the target excavation surface by the area limited excavation control regardless of whether the pipe breakage control valve is mounted or not, and the work device enters below the target excavation surface. Or, the occurrence of an event that the target excavation surface is not sufficiently approached can be avoided.

It is a figure which shows the external appearance of the working machine which concerns on one embodiment of this invention. It is a figure which shows the hydraulic drive device and area | region limited excavation control apparatus of the hydraulic shovel concerning the 1st Embodiment of this invention. It is a figure which shows the hardware constitutions of a control unit. It is a block diagram which shows the control function of a control unit. It is a block diagram which shows the detail of the calculation function of an area | region limited excavation control calculating part. It is a figure which shows two types of 1st correlation tables for arm clouds. It is a figure which shows an example of the calculation process of an arm cylinder speed calculating part. It is a figure which shows two types of 2nd correlation tables for boom raising. It is a figure which shows an example of the calculation process of a boom operation signal control value calculating part. It is a figure which shows an example of the calculation process of a restriction | limiting control calculating part. It is a figure which shows an example of the calculation process of a restriction | limiting control calculating part. It is a figure which shows an example of correction | amendment operation | movement locus | trajectory when a bucket front-end | tip is above a target excavation surface. It is a figure which shows an example of the correction | amendment operation | movement locus | trajectory when the bucket front-end | tip protrudes from the target excavation surface. It is a figure which shows the detail of a pipe fracture control valve. It is a figure which shows the hydraulic drive device and area | region limited excavation control apparatus of the hydraulic shovel concerning the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

-First embodiment-
~Constitution~
<Working machine (hydraulic excavator)>
FIG. 1 is an external view of a work machine according to a first embodiment of the present invention. In this embodiment, the work machine is a hydraulic excavator. Further, in this specification, the operator who has arrived at the driver's seat is referred to as front, rear, left, and right.

  In FIG. 1, the hydraulic excavator according to the present embodiment includes a vehicle body 110 and a work device 120. The vehicle body 110 includes a lower traveling body 111 and an upper swing body 112.

  In this embodiment, the lower traveling body 111 includes left and right crawlers (traveling drive bodies) 113a and 113b having endless track tracks, and the left and right crawlers 113a and 113b are driven by the left and right traveling motors 3e and 3f, respectively. Drive on. The traveling motors 3e and 3f are hydraulic motors.

  The upper turning body 112 is mounted on the lower traveling body 111 so as to be turnable via a turning device (not shown). A cabin 114 on which the operator is boarded is provided on the left side of the front part of the upper swing body 112, and on the rear side of the cabin 114 is the power of an engine, a hydraulic drive source (main hydraulic pump 2 and pilot pump 7 described later), and the like. A power chamber 115 that houses the equipment is mounted with a counterweight 116 that adjusts the balance of the entire hydraulic excavator in the front-rear direction. The upper turning body 112 is driven to turn relative to the lower traveling body 111 by a turning motor 3d (FIG. 2) provided in a turning device (not shown). The turning motor 3d is a hydraulic motor.

  The working device 120 is a device for performing work such as excavation of earth and sand, and is provided in the front portion of the upper swing body 112 (in the present embodiment, on the right side of the cabin 114). The working device 120 is an articulated working device that includes a boom 121, an arm 122, and a bucket 123. The boom 121 is connected to the base frame of the upper swing body 112 by pins (not shown) extending in the left and right directions, and pivots up and down by the expansion and contraction of the boom cylinder 3a. The arm 122 is connected to the tip of the boom 121 by a pin (not shown) extending to the left and right, and rotates with respect to the boom 121 by the expansion and contraction of the arm cylinder 3b. The bucket 123 is connected to the tip of the arm 122 by pins (not shown) extending horizontally and horizontally, and rotates with respect to the arm 122 by expansion and contraction of the bucket cylinder 3c. Each of the boom cylinder 3a, the arm cylinder 3b, and the bucket cylinder 3c is a hydraulic cylinder.

  The hydraulic excavator also includes various detectors that detect information related to position and orientation. For example, angle detectors 8 a to 8 c are provided at the respective rotation fulcrums of the boom 121, the arm 122, and the bucket 123, and detect the rotation angles of the boom 121, the arm 122, and the bucket 123, respectively. The upper swing body 112 is provided with an inclination detector 8d. The inclination detector 8d detects at least one inclination of the upper swing body 112 in the front-rear direction and the left-right direction. The angle detectors 8a to 8c and the inclination detector 8d constitute a work device posture detection device 8 (FIGS. 2 and 3) that detects information related to the position and posture of the work device 120.

<Hydraulic drive>
FIG. 2 is a diagram showing a hydraulic drive device and an area limited excavation control device for a hydraulic excavator according to the present embodiment.

  In FIG. 2, a hydraulic drive device for a hydraulic excavator according to the present embodiment includes a hydraulic pump 2 driven by an engine (not shown) and the boom cylinder 3a driven by pressure oil discharged from the hydraulic pump 2. , A plurality of hydraulic actuators including an arm cylinder 3b, a bucket cylinder 3c, a swing motor 3d, and left and right traveling motors 3e, 3f, and a boom provided corresponding to the plurality of hydraulic actuators 3a to 3f and instructing the operation of the boom Operating device 4a, arm operating device 4b for instructing the operation of the arm, bucket operating device 4c for instructing the operation of the bucket, turning operating device 4d, left and right crawlers 13, 13 A plurality of operation devices including the operation devices 4e and 4f, a hydraulic pump 2, and a plurality of hydraulic actuators 3a to 3f A plurality of flow control valves connected to the boom, the boom flow control valve 5a, which is driven according to the operation of the boom operation device 4a and controls the flow of pressure oil supplied to the boom cylinder 3a, and the arm operation Driven according to the operation of the device 4b, driven according to the operation of the arm flow control valve 5b for controlling the flow of pressure oil supplied to the arm cylinder 3b, and the bucket operation device 4c, and supplied to the bucket cylinder 3c. A flow control valve 5c for buckets for controlling the flow of pressure oil, a flow control valve 5d for turning, which is driven according to the operation of the turning operation device 4d and controls the flow of pressure oil supplied to the turning motor 3d, A plurality of flow control valves 5e and 5f for left and right traveling, which are driven according to the operation of the left and right traveling operation devices 4e and 4f and control the flow of pressure oil supplied to the left and right traveling motors 3e and 3f. A flow control valve, a relief valve 6 which is opened when the pressure between the hydraulic pump 2 and the flow control valve 5a~5f exceeds the set value, and a pilot pump 7.

  The operation devices 4a to 4f have operation levers 4a1 to 4f1 operated by an operator, respectively, and based on the discharge pressure of the pilot pump 7, the operation pilot pressure corresponding to the operation amount and the operation direction of the operation levers 4a1 to 4f1 Is generated. The flow control valves 5a to 5f are hydraulic pilot types having pressure receiving portions 5a1, 5a2 to 5f1 and 5f2, respectively, and the operation pilot pressure generated by the operation devices 4a to 4f is transmitted through the pilot lines 11a, 11b to 16a and 16b. The flow rate control valves 5a to 5f are guided to the pressure receiving portions 5a1, 5a2 to 5f1 and 5f2, and the flow rate control valves 5a to 5f are switched by the pilot pressure.

  The bottom side chamber 3a1 and the rod side chamber 3a2 of the boom cylinder 3a are connected to the boom flow control valve 5a via a pair of first and second hydraulic pipes (hydraulic hoses) 21a and 21b, respectively. A boom pipe break control valve 22 is attached to the bottom side chamber 3a1 portion on the outer surface of the cylinder of the boom cylinder 3a, and the first hydraulic line 21a is connected to the bottom side chamber 3a1 of the boom cylinder 3a via the pipe break control valve 22. It is connected.

  Similarly, the bottom side chamber 3b1 and the rod side chamber 3b2 of the arm cylinder 3b are connected to the arm flow control valve 5b via a pair of third and fourth hydraulic lines (hydraulic hoses) 23a and 23b, respectively. An arm pipe break control valve 24 is attached to the rod side chamber 3b2 portion on the outer surface of the cylinder of the arm cylinder 3b, and the fourth hydraulic line 23b is connected to the rod side chamber 3b2 of the arm cylinder 3b via the pipe break control valve 24. It is connected.

  When the working device 120 is not in contact with the ground, the load pressure due to the weight of the working device 120 acts on the bottom side chamber 3a1 of the boom cylinder 3a. At that time, the load pressure due to the weight of the working device 120 is also exerted on the first hydraulic pipe 21a. Works. When the working device 120 is in a posture in which the arm 122 is extended, the load pressure due to the weight of the front side portion acts on the rod side chamber 3b2 of the arm cylinder 3b, and at that time, the fourth hydraulic pipe line 23b is applied to the fourth hydraulic line 23b. Also, the load pressure due to the weight of the working device 120 acts. When the first and fourth hydraulic pipelines 21a and 23b are in such a state and the first hydraulic pipeline 21a / fourth hydraulic pipeline 23b breaks, the pipe break control valves 22 and 24 are closed, The fall of the working device 120 is prevented.

<Piping break control valve>
FIG. 14 is a view showing details of the pipe breakage control valve 22 for the boom.

  The boom pipe break control valve 22 is mounted on the outer surface of the cylinder of the boom cylinder 3a, and the first hydraulic line 21a is connected to the bottom chamber 3a1 of the boom cylinder 3a via the pipe break control valve 22. A bypass line 201 branches from the first hydraulic line 21 a, and an on-off valve 202 is connected to the bypass line 201. The downstream side of the bypass line 201 is connected to a tank. In the drawing, the electromagnetic proportional valves 54a and 54b and the shuttle valve 33 shown in FIG. 2 are not shown.

  The actuator port on the boom raising side of the flow control valve 5a is connected to the bottom side chamber 3a1 of the boom cylinder 3a via the first hydraulic line 21a and the pipe breaking control valve 22, and the actuator port on the boom lowering side is the second hydraulic line. It is connected to the rod side chamber 3a2 of the boom cylinder 3a via 21b.

  The pipe breakage control valve 22 includes a poppet valve 211 as a main valve and a spool valve 212 as a pilot valve that is operated by an operation pilot pressure from the operation device 4a to operate the poppet valve 211.

  The poppet valve 211 includes a poppet valve body 211a, a pipe connection chamber 211b connected to the first hydraulic line 21a, a cylinder connection chamber 211c connected to the bottom side chamber 3a1 of the boom cylinder 3a, and a back pressure chamber 211d. The poppet valve body 211a is slidably disposed in the housing so as to receive the pressure of the back pressure chamber 211d on the back surface and to block and communicate between the cylinder connection chamber 211c and the pipe connection chamber 211b. The poppet valve body 211a is provided with a passage 211e for communicating the cylinder connection chamber 211c and the back pressure chamber 211d, and a throttle element (fixed throttle element) 211f provided in the passage 211e. A light spring (not shown) that holds the poppet valve body 211a in the illustrated blocking position is disposed in the back pressure chamber 211d.

  The cylinder connection chamber 211c of the poppet valve 211 is connected to the pipe connection chamber 211b via the pilot passage 215, the spool valve 212 and the pilot passage 216, and the back pressure chamber 211d of the poppet valve 211 is connected to the pilot passage 217, the spool valve. 212 and the pilot passage 216 are connected to the pipe connection chamber 211b.

  The spool valve 212 includes a first variable restrictor 212a that controls communication between the pilot passage 215 and the pilot passage 216, and a second variable restrictor 212b that controls communication between the pilot passage 217 and the pilot passage 216. . A spring 212c for setting an initial valve opening force of the spool valve 212 is provided at the valve-closing direction operation end of the spool valve 212, and a boom generated by the operating device 4a is provided at the valve-opening direction operation end of the spool valve 212. A pressure receiving portion 212 d through which the lowering operation pilot pressure is guided through the oil passage 204 is provided.

  The on-off valve 202 can be switched between a closed position on the lower side in the figure and a throttle position on the upper side in the figure. The on-off valve 202 has a spring 202 a that operates in the opening direction and a pressure receiving unit 202 b that operates in the closing direction. The pressure receiving unit 202 b is connected to the pilot line 11 a via a passage 246.

  When the operation lever 4a1 of the operation device 4a is operated in the boom raising direction, the boom raising pilot pressure is guided to the pressure receiving portion 5a1 of the flow control valve 5a via the pilot line 11a, and the flow control valve 5a is switched to the left position in the figure. It is done. When the flow control valve 5a is switched to the left position in the drawing, the pressure oil discharged from the hydraulic pump 2 is supplied to the first hydraulic line 21a via the flow control valve 5a. At this time, the operation pilot pressure is also guided to the pressure receiving portion 202b of the on-off valve 202, the on-off valve 202 is switched to the closed position, and the bypass line 201 is closed. As a result, the pressure oil supplied to the first hydraulic line 21a pushes and opens the poppet valve body 211a of the poppet valve 211 of the pipe breakage control valve 22, and is supplied to the bottom side chamber 3a1 of the boom cylinder 3a. The pressure oil in the rod side chamber 3a2 of the boom cylinder 3a is discharged to the tank via the second hydraulic line 21b and the flow rate control valve 5a. Thereby, the boom cylinder 3a is driven in the extending direction, and the boom 121 (FIG. 1) is driven in the raising direction.

  When the operation lever 4a1 of the operating device 4a is operated in the boom lowering direction, the pilot pressure for lowering the boom is guided to the pressure receiving portion 5a2 of the flow control valve 5a and the pressure receiving portion 212d of the spool valve 212 of the pipe breakage control valve 22. The flow rate control valve 5a is switched to the right side in the figure by the pilot pressure, and the pressure oil discharged from the hydraulic pump 2 enters the rod side chamber 3a2 of the boom cylinder 3a via the flow rate control valve 5a and the second hydraulic line 21b. Supplied. Further, the spool valve 212 of the pipe breakage control valve 22 is opened by the pilot pressure applied to the pressure receiving portion 212d, and accordingly, the poppet valve 211 of the pipe breakage control valve 22 is also opened. At this time, the on-off valve 202 is held in the open position (throttle open position) on the upper side in the figure by the biasing force of the spring 22b, and the first hydraulic line 21a is connected via both the on-off valve 202 and the flow control valve 5a. The pressure oil in the bottom side chamber 3a1 of the boom cylinder 3a passes through the poppet valve 211 of the pipe break control valve 22, the first hydraulic line 21a, the flow rate control valve 5a, the bypass line 201, and the on-off valve 202. Is discharged. Thereby, the boom cylinder 3a is driven in the contracting direction, and the boom 121 (FIG. 1) is driven in the downward direction.

  In the bypass line 201, the on-off valve 202 is held at the throttle position, and the first hydraulic line 21a communicates with the tank via the bypass line 201, so that the pipe break control valve 22 and the flow rate control valve 5a are opened. Even when the pipe break control valve 22 is opened prior to the opening of the flow control valve 5a due to inconsistency in the valve timing, the pipe break control valve 22 opens to the first hydraulic line 21a at the moment when the pipe break control valve 22 is opened. Since the inflowing pressure oil flows out from the bypass line 201 to the tank, the pressure oil that has flowed into the first hydraulic line 21a is not confined in the first hydraulic line 21a, and from the bottom side chamber 3a1 of the boom cylinder 3a. The pressure oil can be discharged smoothly into the tank, and the drive operability at the beginning of the movement of the boom cylinder 3a does not deteriorate. In addition, since the first hydraulic line 21a communicates with the tank via the bypass line 201, tuning of the opening timings of the pipe breakage control valve 22 and the flow rate control valve 5a becomes unnecessary.

  When the operation lever 4a1 of the operation device 4a is not operated and the flow control valve 5a is maintained at the neutral position to hold the load, a load pressure is generated in the bottom side chamber 3a1 of the boom cylinder 3a and becomes high pressure. The poppet valve 211a is guided to the back pressure chamber 211d via the throttle element 211f, and the poppet valve body 211a is urged downward in the figure by the high pressure of the back pressure chamber 211d, so that the poppet valve 211 is held at the shut-off position (check valve function). ). As a result, the load pressure on the bottom side of the boom cylinder 3a is maintained, and the working device 120 is prevented from dropping due to oil leakage.

  During the boom lowering operation (normal time), the pipe break control valve 22 and the flow control valve 5a are opened as described above, and the pressure (load pressure) on the bottom side of the boom cylinder 3a is applied to the first hydraulic line 21a. While controlling the flow rate, the discharge flow rate is controlled by the flow rate control valve 5a, the pipe breakage control valve 22, and the bypass line 201 to adjust the speed. Under such circumstances, in the unlikely event that the first hydraulic pipeline 21a breaks, the pressure in the first hydraulic pipeline 21a drops to almost atmospheric pressure, so the poppet valve 211 of the pipe fracture control valve 22 The poppet valve body 211a is pushed downward in the figure by the high pressure of the back pressure chamber 211d, and the poppet valve 211 is switched to the blocking position. As a result, the operator returns the operation lever 4a1 of the operation device 4a to the neutral position, the operation pilot pressure is set to the tank pressure (0), and the spool valve 212 of the pipe breakage control valve 22 is returned to the closed position on the left side in the figure, whereby the boom cylinder The outflow of the pressure oil from the bottom side chamber 3a1 of 3a is prevented, and further dropping of the boom 121 is prevented.

  The arm pipe breakage control valve 24 connects the cylinder connection chamber 211c of the poppet valve 211 to the rod side chamber 3b2 of the arm cylinder 3b in the boom pipe breakage control valve 22 shown in FIG. 21b is connected to the bottom side chamber 3b1 of the arm cylinder 3b instead of the fourth hydraulic line 23b. The other configuration of the arm pipe breakage control valve 24 is the same as that of the boom pipe breakage control valve 22 shown in FIG.

  In this embodiment, the pipe break control valves 22 and 24 are mounted on both the first hydraulic line 21a of the boom cylinder 3a and the fourth hydraulic line 23b of the arm cylinder 3b. The pipe breakage control valve 22 or the pipe breakage control valve 24 may be mounted on only one of the hydraulic line 21a and the fourth hydraulic line 23b of the arm cylinder 3b.

<Area limited excavation control device>
The hydraulic excavator area limited excavation control apparatus according to the present embodiment is provided in a hydraulic excavator provided with the hydraulic drive apparatus as described above, and the bucket 123 of the work apparatus 120 is below the target excavation surface L (see FIG. 11). The movement of the working device 120 is controlled so as not to enter. This area limited excavation control device includes the above-described angle detectors 8a to 8c and inclination detector 8d (working device attitude detection device 8), a target excavation surface setting device 30 for instructing setting of a target excavation surface L, and a boom Pressure detectors 51a and 51b (which are provided on the boom raising pilot line 11a and the boom lowering pilot line 11b of the operating device 4a and detect the operating pilot pressure for raising the boom and the operating pilot pressure for lowering the boom as operation amounts of the operating device 4a. The operator operation detecting device 31) is provided in the arm cloud pilot line 12a and the arm dump pilot line 12b of the arm operation device 4b, and the arm cloud operation pilot pressure and the arm dump operation pilot are operated as the operation amount of the operation device 4b. Pressure detectors 52a and 52b for detecting pressure (operator operation An output device 31), an electromagnetic proportional valve 54a whose primary port side is connected to the pilot pump 7, reduces the pilot pressure from the pilot pump 7 in response to an electrical signal, and generates a control pilot pressure for raising the boom, and a boom operation The boom raising side pilot line 11a of the device 4a and the output port side of the electromagnetic proportional valve 54a are connected to the boom raising operation pilot pressure of the boom operating device 4a and the boom raising control pilot pressure generated by the electromagnetic proportional valve 54a. A shuttle valve 33 that selects the high pressure side and leads to the pressure receiving portion 5a1 on the boom raising side of the flow control valve 5a and the pilot line 11b on the boom lowering side of the boom operating device 4a are installed. An electromagnetic proportional valve 54b for reducing and outputting the operation pilot pressure, and an arm cloud side of the arm operation device 4b. Installed in the pilot line 12a, the electromagnetic proportional valve 55a for reducing the arm pilot operating pilot pressure according to the electrical signal and outputting it, and the pilot line 12b on the arm dump side of the arm operating device 4b. Correspondingly, an electromagnetic proportional valve 55b for reducing and outputting the operation pilot pressure of the arm dump, and an image / related to the area limited excavation control of the vehicle body 110, the work device 120, the target excavation surface L, etc. A display device 34 for displaying numerical information and a control unit 35 are provided.

  The hydraulic excavator according to the present embodiment includes an information management device 36 (information setting device) that inputs and sets various information related to the specifications of the hydraulic excavator. One of the information input and set in the information management device 36 includes whether or not the hydraulic excavator has a specification including a pipe break control valve. In the information management device 36, flag information indicating whether or not the pipe breakage control valve is mounted may be set at the time of factory shipment, or may be set by an operator after the factory shipment. In the present embodiment, as described above, since the excavator includes the pipe break control valves 22 and 24, the information management device 36 has a pipe break control valve flag.

  The control unit 35 includes a detection signal of the work device attitude detection device 8, a setting signal of the target excavation surface setting device 30, a detection signal of the operator operation detection device 31, and flag information indicating whether or not the pipe breakage control valve of the information management device 36 is mounted. Is input, a predetermined calculation process is performed, and a display signal and a control signal (electric signal) are output to the display device 34 and the electromagnetic proportional valves 54a, 54b, 55a, and 55b. For example, when the control unit 35 is activated (when a key switch (not shown) is turned on), the control unit 35 inputs the pipe break control valve of the information management device 36 from the information management device 36 to the pipe break control valve. This is done by reading a flag indicating whether or not it is installed. Once the flag indicating whether or not the pipe break control valve is mounted is read, the same flag is held until the key switch is turned off and the control unit 35 is turned off.

  FIG. 3 is a diagram illustrating a hardware configuration of the control unit 35.

  The control unit 35 includes an input unit 35a, a central processing unit (CPU) 35b that is a processor, a read only memory (ROM) 35c and a random access memory (RAM) 35d that are storage devices, and an output unit 35e. ing. The input unit 35a includes a detection signal from the work device attitude detection device 8, a setting signal from the target excavation surface setting device 30, a detection signal from the operator operation detection device 31, and whether or not the pipe break control valve set in the information management device 36 is mounted. It functions as an interface of the control unit 35 such as inputting the flag information and performing A / D conversion. The ROM 35c is a recording medium (storage device) that stores a control program for executing functions to be described later of the control unit 35 and various data necessary for executing the functions. The CPU 35b is a control stored in the ROM 35c. A predetermined calculation process is performed on the signal taken from the input unit 35a according to the program. The output unit 35e creates an output signal according to the calculation result in the CPU 35b, and outputs the signal to the display device 34 and the electromagnetic proportional valves 54a, 54b, 55a, and 55b.

  The control unit 35 in FIG. 3 includes semiconductor memories such as ROM 35c and RAM 35d as storage devices, but may be any other storage device, for example, a magnetic storage device such as a hard disk drive. May be. Also, instead of the information management device 36, information on whether or not the pipe breakage control valve is installed may be set in an external personal computer, and the information on whether or not the pipe breakage control valve is installed may be input by connecting the external personal computer to the control unit 35.

  FIG. 4 is a block diagram showing the control function of the control unit 35.

  The control unit 35 has functions of a work device attitude calculation unit 41, a target excavation surface calculation unit 42, an area limited excavation control calculation unit 43, and an electromagnetic proportional valve control unit 44.

  The work device attitude calculation unit 41 is configured to detect the rotation angle of the boom 121, the arm 122, and the bucket 123 detected by the work device attitude detection device 8 (angle detectors 8a to 8c and the inclination detector 8d) and the front and rear of the upper swing body 112. Based on the inclination angle, the position and orientation of the work device 120 are calculated.

  The target excavation surface calculation unit 42 calculates the target excavation surface L based on the setting signal from the target excavation surface setting device 30, and stores the target excavation surface L in the RAM 35d. The region above and above the target excavation surface L is an excavable region where the tip of the bucket 123 can move, and the target excavation surface L is set at the boundary of the excavable region. In the present embodiment, the target excavation surface L is automatically generated as appropriate according to the position of the tip of the bucket 123, for example. The target excavation plane L is expressed by a linear expression in the XY coordinate system, for example, by setting an XY coordinate system (orthogonal coordinate system) with the boom pivot point as the origin.

  The area-limited excavation control calculation unit 43 includes signals / information from the work device attitude calculation unit 41, the target excavation surface calculation unit 42, the operator operation detection device 31 (pressure detectors 51a, 51b, 52a, 52b), and the information management device 36. The vertical movement speed at which the bucket 123 approaches the target excavation plane L decreases as the bucket 123 approaches the target excavation plane L so that the bucket tip of the working device 120 does not enter below the target excavation plane L. In order to control the movement of the working device 120 so as to perform the control, the control values of the operation signals of the boom operation device 4a and the arm operation device 4b are calculated. Further, if necessary, in order to raise the boom without the boom raising operation by the operator, the control speed in the raising direction of the boom cylinder 3a is calculated, and the control value of the operation signal of the boom operating device 4a is calculated. The electromagnetic proportional valve control unit 44 is based on the control values of the operation signals of the boom operation device 4a and the arm operation device 4b calculated by the region restriction excavation control calculation unit 43, and the electromagnetic proportional valves 54a, 54b, 55a, 55b drive signal (electrical signal) is generated and output. The display device 34 displays various information calculated by the area limited excavation control calculation unit 43 on the display screen as image / numerical information.

  FIG. 5 is a block diagram showing details of the calculation function of the area limited excavation control calculation unit 43.

  The area limited excavation control calculation unit 43 has functions of a cylinder speed calculation unit (first calculation unit) 43a, a limit control calculation unit (second calculation unit) 43b, and an operation signal control value calculation unit (third calculation unit) 43c. Have.

  The cylinder speed calculation unit 43a calculates the drive speed (boom cylinder speed) of the boom cylinder 3a by the operator's operation of the boom operation device 4a and the drive speed (arm cylinder speed) of the arm cylinder 3b by the operation of the arm operation device 4b. The calculation includes the first correlation table (correlation) for the boom between the operation pilot pressure (operation signal) of the boom operation device 4a and the drive speed of the boom cylinder 3a, and the arm operation device. A first correlation table (correlation) for the arm between the operation pilot pressure (operation signal) 4b and the drive speed of the arm cylinder 3b is used. The first correlation table for the boom includes a first correlation table for raising the boom and a first correlation table for lowering the boom. The first correlation table for raising the boom and the first correlation table for lowering the boom include Two types of first correlation tables are stored in the ROM 35c depending on whether or not the pipe breakage control valve 22 is mounted. Similarly, the first correlation table for the arm includes a first correlation table for the arm cloud and a first correlation table for the arm dump, and the first correlation table for the arm cloud and the first correlation table for the arm dump include Depending on whether or not the arm pipe breakage control valve 24 is mounted, two types of first correlation tables are stored in the ROM 35c. The cylinder speed calculation unit 43a is used for raising the boom and lowering the boom on the basis of the flag information indicating whether or not the pipe break control valve is set in the information management device 36 (depending on whether or not the pipe break control valve 24 is mounted). The first correlation table corresponding to each of the two types of first correlation tables and the two types of first correlation tables for arm cloud and arm dump is selected, and the driving speed of the boom cylinder 3a is selected using the first correlation table. And the drive speed of the arm cylinder 3b is calculated. Note that mathematical expressions may be used instead of the correlation table.

  The restriction control calculation unit 43b is configured to determine the positional relationship between the work device 120 and the target excavation surface L based on the posture of the work device 120 calculated by the work device posture calculation unit 41 and the target excavation surface L calculated by the target excavation surface calculation unit 42. The distance D) from the target excavation surface L of the bucket tip is calculated, and the driving speed of the boom cylinder 3a and the arm cylinder 3b calculated by the cylinder speed calculation unit 43a and the positional relationship between the working device 120 and the target excavation surface L are calculated. Based on this, a control value (target drive speed for limit control) of the boom cylinder 3a and arm cylinder 3b for controlling the bucket tip of the working device 120 so as not to enter below the target excavation surface L is calculated. .

  The operation signal control value calculation unit 43c operates the boom operation device 4a and the arm operation device 4b based on the control values (control speeds) of the boom cylinder 3a and the arm cylinder 3b obtained by the restriction control calculation unit 43b. A control value of pilot pressure (operation signal) (target pilot pressure for limiting control (target operation signal)) is calculated. The calculation includes the driving speed of the boom cylinder 3a and the operation pilot of the boom operation device 4a. The second correlation table (correlation function) for the boom with the pressure (operation signal), and the second correlation table for the arm with the driving speed of the arm cylinder 3b and the operation pilot pressure (operation signal) of the arm operation device 4b ( Correlation function). The second correlation table for the boom includes a second correlation table for raising the boom and a second correlation table for lowering the boom. The second correlation table for raising the boom and the second correlation table for lowering the boom are used for the boom. Two types of second correlation tables are stored in the ROM 35c depending on whether or not the pipe breakage control valve 22 is mounted. Similarly, the second correlation table for the arm includes a second correlation table for the arm cloud and a second correlation table for the arm dump, and the second correlation table for the arm cloud and the second correlation table for the arm dump include Two types of second correlation tables are stored in the ROM 35c depending on whether or not the arm pipe breakage control valve 24 is mounted. The operation signal control value calculation unit 43c is used for raising the boom and lowering the boom based on the flag information indicating whether or not the pipe breakage control valve is set (set according to the presence or absence of the pipe breakage control valve 22) set in the information management device 36. Corresponding second correlation table is selected from each of the two types of second correlation tables and two types of second correlation tables for arm cloud and arm dump, and the boom operation device is selected using the second correlation table. The control value of the operation pilot pressure 4a and the control value of the operation pilot pressure of the arm operation device 4b are calculated. Here, mathematical expressions may be used instead of the correlation table.

  As in the embodiment shown in FIG. 15, which will be described later, also in this embodiment, a pressure detector for detecting the pilot pressure for bucket cloud and bucket dump is provided as the operator operation detection device 31 for correction operation. Proportional solenoid valves for bucket cloud and bucket dump are provided as electromagnetic proportional valves. In the cylinder speed calculation unit 43a, the operation pilot pressure (operation signal) of the bucket operating device 4c and the driving speed of the bucket cylinder 3c are used for the bucket. Using the first correlation table (correlation), the operation speed of the bucket cylinder 3c (bucket cylinder speed) by the operation of the bucket operating device 4c by the operator is calculated, and the operation signal control value calculation unit 43c drives the bucket cylinder 3c. Speed and operation pilot pressure of operation device 4c for bucket (operation signal) It may be calculated control value of the operation pilot pressure of the bucket operating device 4c (operation signal) second using a correlation table (correlation function) for the bucket.

  The control value of the operation pilot pressure of the boom operation device 4a and the arm operation device 4b calculated by the operation signal control value calculation unit 43c is output to the electromagnetic proportional valve control unit 44 as a control command value. The electromagnetic proportional valve control unit 44 is based on the control values of the operation pilot pressures of the boom operation device 4a and the arm operation device 4b calculated by the operation signal control value calculation unit 43c, and the electromagnetic proportional valves 54a, 54b, Drive signals (electric signals) for 55a and 55b are generated and output to the electromagnetic proportional valves 54a, 54b, 55a and 55b. The electromagnetic proportional valves 54a, 54b, 55a, 55b are used for the boom operation device 4a so that the drive speeds of the boom cylinder 3a and the arm cylinder 3b are equal to the control speeds of the boom cylinder 3a and the arm cylinder 3b calculated by the limit control calculation unit 43b. Further, the operation pilot pressure (operation signal) of the arm operation device 4b is corrected.

  In the above, the cylinder speed calculation unit 43a has the first correlations from the operation signals of at least some of the plurality of specific operation devices 4a and 4b among the plurality of operation devices 4a to 4c instructing the operation of the work device 120. A first calculation unit is configured to calculate the driving speeds of the plurality of hydraulic cylinders 3a and 3b corresponding to the plurality of specific operation devices 4a and 4b using the function.

  Based on the drive speed of the plurality of hydraulic cylinders 3a and 3b calculated by the first calculation unit 43a and the positional relationship between the work device 120 and the target excavation surface L, the limit control calculation unit 43b is configured to perform the target excavation by the work device 120. A second calculator that calculates control values of the drive speeds of at least some of the plurality of hydraulic cylinders 3a to 3c that drive the working device 120 so as not to enter below the surface L. Configure.

  The operation signal control value calculation unit 43c uses the second correlation function to control the plurality of specific hydraulic cylinders 3a, 3b from the control values of the driving speeds of the plurality of specific hydraulic cylinders 3a, 3b calculated by the second calculation unit 43b. 3rd calculating part which calculates the control value of the operation signal of the some operating devices 4a and 4b corresponding to 3b is comprised.

  The electromagnetic proportional valve control unit 44 and the electromagnetic proportional valves 54a, 54b, 55a, and 55b allow the work device 120 to perform target excavation based on the control values of the operation signals of the plurality of operation devices 4a and 4b calculated by the third calculation unit 43c. An operation signal correction device that corrects the operation signals of the plurality of operation devices 4a and 4b corresponding to the plurality of specific hydraulic cylinders 3a and 3b so as not to enter below the surface L is configured.

  Further, the plurality of hydraulic cylinders 3a, 3b corresponding to the plurality of specific operation devices 4a, 4b include the hydraulic cylinders 3a, 3b related to the pipe breakage control valves 22, 24, and the first calculation unit 43a has a first correlation. As a function, a specific first correlation function for the hydraulic cylinder related to the pipe break control valves 3a, 3b is included, and a plurality of specific hydraulic cylinders 3a, 3b are connected to the hydraulic cylinders 3a, 3b related to the pipe break control valves 22, 24. And the third calculation unit 43c includes a specific second correlation function for the hydraulic cylinder related to the pipe breakage control valves 22 and 24 as the second correlation function, and the first calculation unit 43a and the third calculation unit 43c include The information regarding whether or not the pipe breakage control valves 22 and 24 are mounted is input from the information management device 36 which is an information setting device, and a specific first correlation is determined depending on whether or not the pipe breakage control valves 22 and 24 are mounted. The calculation processing by the number and the specific second correlation function is corrected to correspond to the hydraulic cylinders 3a, 3b related to the driving speed of the hydraulic cylinders 3a, 3b related to the pipe break control valves 22, 24 and the pipe break control valves 22, 24. The control values of the operation signals of the operation devices 4a and 4b are respectively calculated.

  FIG. 6 is a diagram illustrating an example of two types of first correlation tables set in the cylinder speed calculation unit 43a. In the figure, the correlation table having the solid line characteristic is the first correlation table when the pipe breakage control valve is mounted, and the correlation table having the broken line characteristic is the first correlation table when the pipe breakage control valve is not mounted. It is.

  For example, in the boom raising operation for extending the boom cylinder 3a, when the boom cylinder 3a includes the pipe break control valve 22, the pressure oil supplied to the bottom side chamber 3a1 of the boom cylinder 3a is supplied to the poppet valve 211 of the pipe break control valve 22. The poppet valve body 211a is pushed up and supplied to the bottom chamber 3a1 of the boom cylinder 3a. In this way, since the poppet valve 211 operates in the boom raising operation, in the hydraulic excavator provided with the pipe breakage control valve 22, the operation pilot pressure of the boom operation device 4a is compared with the hydraulic excavator not provided with the pipe breakage control valve 22. The relationship between the (operation signal) and the drive speed of the boom cylinder 3a changes. For this reason, the cylinder speed characteristic (solid line) of the first correlation table when the boom pipe break control valve 22 is mounted is the cylinder speed of the first correlation table when the boom pipe break control valve 22 is not mounted. The drive speed of the boom cylinder 3a is smaller than the characteristic (broken line).

  Further, in the boom lowering operation for contracting the boom cylinder 3a, when a load holding pressure is generated in the bottom side chamber 3a1 of the boom cylinder 3a and the boom cylinder 3a is provided with the pipe break control valve 22, the operation pilot pressure for lowering the boom causes the pipe break. Acting on the spool valve 212 of the control valve 22, the poppet valve 211 is opened accordingly, and the pressure oil is discharged from the bottom side chamber 3a1 of the boom cylinder 3a to the tank. Thus, in the boom lowering operation, the spool valve 212 and the poppet valve 211 are operated. Therefore, in the hydraulic excavator provided with the pipe break control valve 22, the boom operation device is compared with the hydraulic excavator not provided with the pipe break control valve 22. The relationship between the operation pilot pressure (operation signal) 4a and the drive speed of the boom cylinder 3a changes. Therefore, also in this case, the cylinder speed characteristic (solid line) of the first correlation table when the boom pipe breakage control valve 22 is mounted is the first correlation when the boom pipe breakage control valve 22 is not mounted. The drive speed of the boom cylinder 3a is smaller than the cylinder speed characteristic (broken line) of the table.

  The same applies to the arm cloud operation that extends the arm cylinder 3b and the arm dump operation that contracts the arm cylinder 3b. The arm pipe breakage control valve 24 serves as a flow path resistance, and the pipe breakage control valve 24 is provided. In the hydraulic excavator, the relationship between the operating pilot pressure (operation signal) of the arm operating device 4b and the driving speed of the arm cylinder 3b changes with respect to the hydraulic excavator not provided with the pipe breakage control valve 24. For this reason, the cylinder speed characteristic (solid line) of the first correlation table when the arm pipe break control valve 24 is mounted is the cylinder speed of the first correlation table when the arm pipe break control valve 24 is not mounted. The drive speed of the arm cylinder 3b is smaller than the characteristic (broken line).

  FIG. 7 is a diagram illustrating an example of calculation processing of the cylinder speed calculation unit 43a.

  The cylinder speed calculation unit 43a includes a selection unit 43a1 and a calculation unit 43a2. The selector 43a1 selects the first correlation table F1 and the pipe rupture control valve when the pipe rupture control valve is installed based on the flag information indicating whether or not the pipe rupture control valve is installed (depending on whether the pipe rupture control valve is installed). One of the first correlation tables F2 when no is mounted is selected. The computing unit 43a2 computes the cylinder driving speed according to the operating pilot pressure of the operating device at that time using the selected first correlation table.

  The cylinder speed calculation unit 43a selects the two types of first correlation tables for raising the boom and lowering the boom and the two types of first correlation tables for the arm cloud and the arm dump, as shown in FIG. 43a1 and a calculation unit 43a2, and calculates the driving speed of the boom cylinder 3a and the driving speed of the arm cylinder 3b based on flag information on whether or not the pipe breakage control valve is mounted (depending on whether or not the pipe breakage control valve is mounted). .

  In the above-described embodiment, two types of first correlation tables are stored in the ROM 35c depending on whether or not the pipe break control valve is mounted, and the cylinder driving speed is calculated depending on whether or not the pipe break control valve is mounted. However, one type of first correlation table is stored in the ROM 35c, and the table data is corrected by multiplying the table data by gain or limiting the maximum value depending on whether or not the pipe breakage control valve is mounted, and the cylinder The driving speed may be calculated. In the above embodiment, the cylinder driving speed is calculated using the correlation table. However, other correlation functions such as a mathematical expression may be used instead of the correlation table. As described above, the cylinder speed calculation unit 43a only needs to be able to calculate the cylinder drive speed by correcting the calculation process based on the correlation function according to whether or not the pipe breakage control valve is mounted, and various modifications are possible within the range.

  FIG. 8 is a diagram illustrating an example of two types of second correlation tables set in the operation signal control value calculation unit 43c. In the figure, the correlation table having the solid line characteristic is the second correlation table when the pipe breakage control valve is mounted, and the correlation table having the broken line characteristic is the second correlation table when the pipe breakage control valve is not mounted. It is.

  As described above, when the pipe break control valves 22 and 24 are mounted, the boom raising operation for extending the boom cylinder 3a, the boom lowering operation for contracting the boom cylinder 3a, the arm cloud operation and the arm for extending the arm cylinder 3b. In the arm dump operation for contracting the cylinder 3b, the pipe breakage control valves 22 and 24 have flow resistance. For this reason, in the hydraulic excavator provided with the pipe break control valves 22 and 24, the drive speed of the boom cylinder 3a and the control pilot pressure of the boom flow control valve 5a (with respect to the hydraulic excavator not provided with the pipe break control valves 22 and 24) And the relationship between the driving speed of the arm cylinder 3b and the control pilot pressure (operation signal) of the arm flow control valve 5b changes. For this reason, the control pilot pressure characteristic (solid line) of the second correlation table when the pipe breakage control valves 22 and 24 are installed is the control pilot pressure characteristic of the second correlation table when the pipe breakage control valves 22 and 24 are not installed. The operating pilot pressure of the operating device is larger than the characteristic (broken line).

  FIG. 9 is a diagram illustrating an example of calculation processing of the operation signal control value calculation unit 43c.

  The operation signal control value calculation unit 43c includes a selection unit 43c1 and a calculation unit 43c2. The selection unit 43c1 uses the second correlation table F3 and the pipe breakage control valve when the pipe breakage control valve is mounted based on the flag information of whether or not the pipe breakage control valve is mounted (depending on whether or not the pipe breakage control valve is mounted). One of the second correlation tables F4 when no is mounted is selected. The calculation unit 43c2 calculates the control value of the operation pilot pressure of the operating device according to the control value of the cylinder driving speed obtained by the limit control calculation unit 43b at that time using the selected second correlation table.

  The operation signal control value calculation unit 43c is shown in FIG. 9 for each of two types of second correlation tables for boom raising and boom lowering and two types of second correlation tables for arm cloud and arm dump. A control unit 43c1 and a calculation unit 43c2 are provided, and based on flag information indicating whether or not a pipe breakage control valve is mounted (depending on whether or not a pipe breakage control valve is mounted), the control value and arm of the operation pilot pressure of the boom operating device 4a The control value of the operating pilot pressure of the operating device 4b is calculated.

  In this case as well, two types of second correlation tables are not stored in the ROM 35c depending on whether or not the pipe break control valve is mounted, but one type of second correlation table is stored in the ROM 35c, and the pipe break control valve is stored. Depending on the presence or absence of mounting, the table data may be corrected by multiplying the table data by a gain, and the control value of the operating pilot pressure may be calculated. Also, other correlation functions such as using mathematical expressions instead of using a correlation table may be used. As described above, the operation signal control value calculation unit 43c also has only to be able to calculate the control value of the operation pilot by correcting the calculation process by the correlation function according to whether or not the pipe breakage control valve is mounted, and various modifications can be made within the range. Is possible.

  10 and 11 are diagrams illustrating an example of a calculation process of the restriction control calculation unit 43b.

  First, the restriction control calculation unit 43b determines whether the work device 120 and the target excavation surface L are based on the posture of the work device 120 calculated by the work device posture calculation unit 41 and the target excavation surface L calculated by the target excavation surface calculation unit 42. As a positional relationship, the distance D from the target excavation surface L at the bucket tip is calculated, and the limit value of the component perpendicular to the target excavation surface L of the bucket tip speed is calculated based on the distance D from the target excavation surface L at the bucket tip. Calculate a. This is done by storing the relationship shown in FIG. 10 in the ROM 35c and reading this relationship.

  10, the horizontal axis indicates the distance D from the target excavation surface L at the bucket tip, the vertical axis indicates the limit value a of the component perpendicular to the target excavation surface L at the bucket tip speed, and the horizontal axis distance D and vertical axis In the shaft speed limit value a, when the excavable area on and above the target excavation surface L is called a set area, the direction from the outside of the set area to the inside of the set area is the (+) direction. The relationship between the distance D and the limit value a is that when the bucket tip is within the set region, the speed in the (−) direction proportional to the distance D is set as the limit value a of the component perpendicular to the bucket tip speed boundary L, When the bucket tip is out of the region, the speed in the (+) direction proportional to the distance D is determined to be the limit value a of the component perpendicular to the bucket tip velocity boundary L. Therefore, within the set area, the speed is reduced only when the component perpendicular to the target excavation surface L of the bucket tip speed exceeds the limit value a in the (−) direction, and outside the set area, the bucket tip increases in the (+) direction. It comes to be quick.

  Next, the restriction control calculation unit 43b is based on the cylinder driving speed (boom cylinder speed and arm cylinder speed) by the operator operation calculated by the cylinder speed calculation unit 43a and the position and posture of the work device 120 obtained by the work device posture calculation unit 41. The bucket tip speed b by the operator operation is calculated.

  Further, the restriction control calculation unit 43b uses the setting data of the target excavation surface L set by the work device attitude calculation unit 41, and performs coordinate conversion to obtain the target excavation surface of the bucket tip speed b by the operator operation obtained as described above. The component bx parallel to L and the component by perpendicular to the target excavation surface L are calculated, the limit value a of the component perpendicular to the target excavation surface L of the bucket tip speed, and the target excavation surface of the bucket tip speed b by the operator's operation A control value c of the component perpendicular to the target excavation surface L of the bucket tip speed by the correction operation is calculated from the component by perpendicular to L. This will be described with reference to FIG.

  In FIG. 11, the difference between the limit value a of the component perpendicular to the target excavation surface L of the bucket tip speed and the component by (a−by) perpendicular to the target excavation surface L of the bucket tip velocity b by the operator operation is the bucket by the correction operation. The control value c of the component perpendicular to the target excavation surface L of the tip speed is calculated, and the limit control calculation unit 43b calculates the control value c from the equation c = a−by.

  The meaning of the control value c by the correction operation will be described separately when the bucket tip is within the set region, when it is on the target excavation surface L, and when it is outside the set region.

  When the bucket tip is within the set region, the bucket tip speed is limited to the limit value a of the component perpendicular to the target excavation surface L of the bucket tip speed in proportion to the distance D from the target excavation surface L of the bucket tip. When the bucket tip speed b by the operator operation exceeds the limit value a, the speed is reduced to the limit value a by the speed c (= a−by) correction operation.

  When the bucket tip is on the target excavation surface L, the limit value a of the component perpendicular to the target excavation surface L of the bucket tip speed is 0, and the bucket tip speed b by the operator operation toward the outside of the setting region is the speed c. Canceled by the correction operation, the bucket tip speed becomes zero.

  When the bucket tip is out of the set region, the component perpendicular to the target excavation surface L of the bucket tip speed is always limited to the upward speed a proportional to the distance D from the target excavation surface L of the bucket tip, so that A speed c correction operation is performed so as to restore the setting area.

  Here, for example, there are the following two correction operations when the operator operation is an arm cloud operation.

(A) Boom raising (b) Combined use of boom raising and arm cloud deceleration The correction operation when the operator operation is boom lowering is, for example,
(C) Deceleration of boom lowering.

  The limit control calculation unit 43b performs coordinate conversion using the control value c of the component perpendicular to the target excavation surface L of the bucket tip speed by the correction operation and the setting data of the target excavation surface L set by the work device attitude calculation unit 41. The control value of the boom cylinder 3a and the arm cylinder 3b for controlling the control value c so that the tip of the bucket 123 of the work device 120 does not enter below the target excavation surface L (for limiting control). Target drive speed).

~ Operation ~
The operation of the present embodiment configured as described above will be described.

<Arm cloud operation>
FIG. 12 shows a correction when the operation lever 4b1 of the arm operation device 4b is operated in the arm cloud direction in an attempt to excavate in the forward direction, and the bucket tip is above the target excavation surface L (within the set region). FIG. 13 is a diagram illustrating an example of an operation locus, and FIG. 13 is a diagram illustrating an example of a correction operation locus when the bucket tip protrudes from the target excavation surface L (out of the set region). First, the case where the correcting operation is performed by raising the boom (a) will be described.

  When the operation lever 4b1 of the arm operation device 4b is operated in the arm cloud direction in an attempt to excavate in the front direction, the operation pilot pressure of the operation device 4b is applied to the pressure receiving portion 5b1 on the arm cloud side of the flow control valve 5b. 122 is moved so as to move downward. On the other hand, at the same time, the operating pilot pressure of the operating device 4b is detected by the pressure detector 52a and is input to the cylinder speed calculating unit 43a to calculate the driving speed of the arm cylinder 3b. At this time, since the operating pilot pressure of the operating device 4b is the operating pilot pressure of the arm cloud, the first correlation table for arm cloud is used for calculating the driving speed of the arm cylinder 3b. In addition, since the arm pipe breakage control valve 24 is provided in the present embodiment, the first correlation table F1 when the arm pipe breakage control valve 24 is mounted is used as the first correlation table for the arm cloud. The cylinder speed calculation unit 43a calculates the drive speed of the arm cylinder 3b using the first correlation table F1.

  The limit control calculation unit 43b calculates the bucket tip speed b by the arm based on the driving speed of the arm cylinder 3b. Further, the limit control calculation unit 43b calculates a bucket tip speed limit value a (<0) proportional to the distance D from the target excavation surface L of the bucket tip from the relationship shown in FIG. A control value c = a−by of the bucket tip speed is calculated. At this time, when the bucket tip is far from the target excavation surface L and a <by (| a |> | by |), the control value c is calculated as a negative value.

  In the operation signal control value calculation unit 43c, since the control value c is a negative value, the control value (target pilot pressure) of the operation pilot pressure for lowering the boom is calculated using the second correlation table for lowering the boom.

  Based on the control value of the boom lowering operation pilot pressure, the electromagnetic proportional valve control unit 44 drives the drive signal (the electromagnetic proportional valve 54b to limit the pilot pressure of the pressure receiving unit 5a2 of the flow control valve 5a on the boom lowering side). Electric signal) is generated and output. Further, the drive signal is not output to the electromagnetic valve 54a on the boom raising side, and the pilot pressure of the pressure receiving portion 5a1 of the flow control valve 5a is set to zero. At this time, since the operating device 4a is not operated, the pilot pressure is not output from the operating device 4a to any of the pressure receiving portions 5a1 and 5a2 of the flow control valve 5a. As a result, the arm 122 is moved in the forward direction according to the operating pilot pressure of the operating device 4b.

  As described above, as the arm 122 is moved in the forward direction and the bucket tip approaches the target excavation surface L, the limit value a of the bucket tip speed calculated by the limit control calculation unit 43b increases (| a | becomes smaller). When the limit value a becomes larger than the component by perpendicular to the target excavation surface L of the bucket tip speed b by the arm, the bucket tip speed control value c = a−by becomes a positive value.

  In the operation signal control value calculation unit 43c, since the control value c is a positive value, the control value of the drive speed of the boom cylinder 3a calculated by the limit control calculation unit 43b is calculated using the second correlation table for raising the boom. Then, the control value of the operation pilot pressure for raising the boom is calculated. In addition, since the boom pipe breakage control valve 22 is provided in the present embodiment, the second correlation table F3 when the boom pipe breakage control valve 22 is mounted is used as the boom raising second correlation table. The operation signal control value calculation unit 43c is selected, and the control value of the boom raising operation pilot pressure is calculated using the second correlation table F3.

  Based on the control value of the boom raising operation pilot pressure, the electromagnetic proportional valve control unit 44 generates a pilot signal of the electromagnetic proportional valve 54a so as to generate the pilot pressure of the pressure receiving unit 5a1 of the boom raising side flow control valve 5a. Signal). Further, a drive signal for closing the electromagnetic proportional valve 54b is output to the electromagnetic proportional valve 54b on the boom lowering side so as to cut off the pilot pressure generated by the operator operation, and the pilot pressure of the pressure receiving portion 5a2 of the flow control valve 5a is output. Set to 0. Thereby, the correction operation by raising the boom is performed so that the component perpendicular to the target excavation surface L of the bucket tip speed is gradually limited in proportion to the distance D from the ket tip and the target excavation surface L, The direction change control as shown in FIG. 12 is performed by the speed corrected by the component bx parallel to the target excavation surface L whose bucket tip speed is not corrected and the control value c, and excavation along the target excavation surface L is performed. Yes. At this time, the cylinder speed calculation unit 43a calculates the drive speed of the arm cylinder 3b using the first correlation table F1 when the arm pipe breakage control valve 24 is mounted, and the operation signal control value calculation unit. In 43c, the control value of the boom raising operation pilot pressure is calculated by using the second correlation table F3 when the boom pipe breakage control valve 22 is mounted. Therefore, it is possible to ensure the control accuracy when shaping the target excavation surface by the area limited excavation control, and avoid the occurrence of an event that the bucket 123 enters below the target excavation surface or is not sufficiently close to the target excavation surface. can do.

  Further, when the bucket tip protrudes from the target excavation surface L, the limit control calculation unit 43b has a bucket tip speed limit value a proportional to the distance D from the target excavation surface L of the bucket tip from the relationship shown in FIG. The control value c = a−by (> 0) of the bucket tip speed calculated by the boom raising correction operation increases in proportion to the limit value a. Using the second correlation table F3 when the pipe breakage control valve 22 is mounted, the control value of the boom raising operation pilot pressure that is increased according to the control value c is calculated.

  The electromagnetic proportional valve control unit 44 generates and outputs a drive signal (electric signal) of the electromagnetic proportional valve 54a that increases in accordance with the control value c based on the control value of the boom raising operation pilot pressure. As a result, a correction operation by raising the boom is performed so that the bucket tip speed proportional to the distance D is restored outside the set region, and in parallel with the target excavation surface L where the bucket tip speed is not corrected by the arm. Due to the component bx and the speed perpendicular to the target excavation surface L corrected by the control value c, excavation while gradually returning along the target excavation surface L can be performed as shown in FIG. Therefore, excavation along the target excavation surface L can be performed smoothly only by clouding the arm. Also in this case, the cylinder speed calculation unit 43a calculates the drive speed of the arm cylinder 3b using the first correlation table F1 when the arm pipe break control valve 24 is mounted, and calculates the operation signal control value. In the part 43c, the control value of the boom raising operation pilot pressure is calculated using the second correlation table F3 when the boom pipe break control valve 22 is mounted. Regardless, it is possible to ensure the control accuracy when shaping the target excavation surface by the area limited excavation control, and the occurrence of an event such that the bucket 123 enters below the target excavation surface or is not sufficiently close to the target excavation surface. It can be avoided.

  When the correction operation is performed in combination with the boom raising and the arm cloud deceleration in (b) above, when the control value c of the bucket tip speed becomes a positive value, the control value c is changed to the correction operation by raising the boom. It is sufficient to distribute the correction operation by the arm cloud deceleration and reduce the vertical component by in each.

  For example, if the control value assigned to the boom raising correction operation is c1, and the control value assigned to the arm cloud deceleration correction operation is c2 (c = c1 + c2), the control value c1 is corrected to raise the boom. As in the case of the control value c by the operation, the control value of the boom raising operation pilot pressure using the second correlation table F3 when the boom pipe breakage control valve 22 is mounted in the operation signal control value calculation unit 43c. The electromagnetic proportional valve control unit 44 may generate and output a drive signal (electric signal) for the electromagnetic proportional valve 54a. For the control value c2, the control value of the operation pilot pressure of the arm cloud is calculated by using the second correlation table F3 when the arm pipe break control valve 24 is mounted in the operation signal control value calculation unit 43c, and the electromagnetic The proportional valve control unit 44 may generate and output a drive signal (electric signal) for the electromagnetic proportional valve 55a. As a result, the electromagnetic proportional valve 54a generates a pilot pressure applied to the pressure receiving portion 5a1 of the boom-up flow control valve 5a, and gradually limits the pilot pressure according to the control value c1. The electromagnetic proportional valve 55a reduces and outputs the pilot pressure of the arm cloud of the operating device 4b, and gradually limits the pilot pressure applied to the pressure receiving portion 5b1 on the arm cloud side of the flow control valve 5b according to the control value c2. To do. As a result, the arm cloud speed is gradually limited as it approaches the target excavation surface L, and the component by perpendicular to the target excavation surface L of the bucket tip speed b by the arm can be reduced by using both boom raising and arm cloud deceleration. it can.

<Boom lowering operation>
When the operation lever 4a1 of the boom operation device 4a is operated in the boom lowering direction in order to position the bucket tip, the operation pilot pressure of the operation device 4a is applied to the boom lowering side of the flow control valve 5a via the pilot line 11b. Given to the pressure receiving part 5a2, the boom 121 is moved downward. On the other hand, at the same time, the operating pilot pressure of the operating device 4a is detected by the pressure detector 51b, and is input to the cylinder speed calculating unit 43a to calculate the driving speed of the boom cylinder 3a. At this time, since the operating pilot pressure of the operating device 4a is the operating pilot pressure for lowering the boom, the first correlation table for lowering the boom is used for calculating the driving speed of the boom cylinder 3a. In addition, since the boom pipe breakage control valve 22 is provided in the present embodiment, the first correlation table F1 when the boom pipe breakage control valve 22 is mounted is used as the boom lowering correlation table. The cylinder speed calculation unit 43a calculates the drive speed of the boom cylinder 3a using the first correlation table F1.

  The restriction control calculation unit 43b calculates the bucket tip speed b by the boom lowering correction operation based on the drive speed of the boom cylinder 3a. Further, the limit control calculation unit 43b calculates a bucket tip speed limit value a (<0) proportional to the distance D from the target excavation surface L of the ket tip from the relationship shown in FIG. c = a−by is calculated. At this time, when the bucket tip is far from the target excavation surface L and a <by (| a |> | by |), the control value c is calculated as a negative value.

  In the operation signal control value calculation unit 43c, since the control value c is a negative value, the control value of the drive speed of the boom cylinder 3a calculated by the limit control calculation unit 43b is calculated using the second correlation table for lowering the boom. Then, the control value of the operation pilot pressure for lowering the boom is calculated. Further, since the boom pipe breakage control valve 22 is provided in the present embodiment, the second correlation table F3 when the boom pipe breakage control valve 22 is mounted is used as the boom lowering correlation table. The operation signal control value calculation unit 43c is selected, and the control value of the boom lowering operation pilot pressure is calculated using the second correlation table F3.

  Based on the control value of the boom lowering operation pilot pressure, the electromagnetic proportional valve control unit 44 drives the drive signal (the electromagnetic proportional valve 54b to limit the pilot pressure of the pressure receiving unit 5a2 of the flow control valve 5a on the boom lowering side). Electric signal) is generated and output. Further, the drive signal is not output to the electromagnetic valve 54a on the boom raising side, and the pilot pressure of the pressure receiving portion 5a1 of the flow control valve 5a is set to zero. At this time, when the bucket tip is far from the target excavation surface L, the absolute value of the bucket tip speed control value c calculated by the boom lowering correction operation calculated by the limit control calculator 43b is large, and the operation signal control value calculator 43c. Since the pilot pressure of the operating device 4a is smaller than the control value of the operating pilot pressure for lowering the boom obtained in step 4, the electromagnetic proportional valve 54b outputs the pilot pressure of the operating device 4a as it is, and thereby the pilot pressure of the operating device 4a. In response, the boom goes down.

  As described above, as the boom lowers and the bucket tip approaches the target excavation surface L, the control value c = a (<0) of the bucket tip speed calculated by the limit control calculation unit 43b increases (| a | | C | becomes smaller), and the absolute value of the control value of the corresponding boom lowering operation pilot pressure (<0) obtained by the operation signal control value calculation unit 43c becomes smaller. When the absolute value of this control value becomes smaller than the operation pilot pressure of the operating device 4a and the drive signal output from the electromagnetic proportional valve control unit 44 to the electromagnetic proportional valve 54b decreases accordingly, the electromagnetic proportional valve 54b The pilot pressure of the operating device 4a is reduced and output, and the pilot pressure applied to the pressure receiving portion 5a2 on the boom lowering side of the flow control valve 5a is gradually limited according to the control value c. Thereby, as the target excavation surface L is approached, the boom lowering speed is gradually limited, and when the bucket tip reaches the target excavation surface L, the boom stops. Therefore, positioning of the bucket tip can be easily and smoothly performed. At this time, the cylinder speed calculation unit 43a uses the first correlation table F1 when the boom pipe breakage control valve 22 is mounted as the first correlation table for lowering the boom to determine the drive speed of the boom cylinder 3a. The calculated operation signal control value calculation unit 43c uses the second correlation table F3 when the boom pipe breakage control valve 22 is mounted as the second correlation table for lowering the boom to calculate the operation pilot pressure for lowering the boom. Since the control value is calculated, the control accuracy when shaping the target excavation surface by the area limited excavation control can be ensured regardless of whether or not the pipe break control valve is installed, and the bucket 123 is located below the target excavation surface. Occurrence of an event of entering or not sufficiently close to the target excavation surface can be avoided.

  Further, when the bucket tip protrudes from the target excavation surface L, the limit control calculation unit 43b has a bucket tip speed limit value a proportional to the distance D from the bucket tip and the target excavation surface L from the relationship shown in FIG. The control value c = a−by (> 0) of the bucket tip speed by the correction operation is also calculated as a positive value that increases in proportion to the limit value a. In the operation signal control value calculating unit 43c, since the control value c is a positive value, the control value of the boom raising operation pilot pressure that increases in accordance with the control value c is obtained using the second correlation table for raising the boom. At the same time, zero is calculated as the control value of the operating pilot pressure for lowering the boom. Further, since the boom pipe break control valve 22 is provided in the present embodiment, the second correlation table F3 when the boom pipe break control valve 22 is mounted is used as the boom raising second correlation table. The control value of the operating pilot pressure for raising the boom that is increased according to the control value c is calculated.

  The electromagnetic proportional valve control unit 44 generates and outputs a drive signal (electric signal) of the electromagnetic proportional valve 54a that increases in accordance with the control value c based on the control value of the boom raising operation pilot pressure, and the boom raising side. A pilot pressure corresponding to the limit value a is applied to the pressure receiving portion 5a1 of the flow control valve 5a. The electromagnetic proportional valve control unit 44 generates and outputs a drive signal (electric signal) of the electromagnetic proportional valve 54a based on the control value of the zero pilot pilot for lowering the boom, and outputs the flow control valve 5a on the boom lowering side. The pilot pressure applied to the pressure receiving portion 5a2 is reduced to the tank pressure. Thereby, the boom is moved in the raising direction so as to be restored in the region at a speed proportional to the distance D, and stops when the bucket tip returns to the target excavation surface L. Therefore, the bucket tip can be positioned more smoothly. Also at this time, the cylinder speed calculation unit 43a uses the first correlation table F1 when the boom pipe breakage control valve 22 is mounted as the boom lowering first correlation table to drive the boom cylinder 3a. And the operation signal control value calculation unit 43c uses the second correlation table F3 when the boom pipe breakage control valve 22 is mounted as the boom raising second correlation table to operate the boom raising operation pilot pressure. Therefore, the control accuracy when shaping the target excavation surface by the area limited excavation control can be ensured regardless of whether or not the pipe breakage control valve is installed, and the bucket 123 is located below the target excavation surface. It is possible to avoid the occurrence of an event such as intruding into the target area or being not sufficiently close to the target excavation surface.

~effect~
As described above, according to the present embodiment, as the first and second correlation tables that are the specific first and second correlation functions, two types of first and second types corresponding to whether or not the pipe breakage control valve is mounted are provided. The second correlation tables F1, F2, F3, and F4 are stored in a ROM (storage device) 35c, and the first and second correlation tables are selected according to whether or not the pipe breakage control valves 22 and 24 are mounted, and the arm cylinder 3b. Control for shaping the target excavation surface by the area limited excavation control regardless of whether the pipe breakage control valves 22 and 24 are installed or not. The accuracy can be ensured, and the occurrence of an event that the bucket 123 enters below the target excavation surface or does not sufficiently approach the target excavation surface can be avoided.

-Second embodiment-
FIG. 15 is a diagram showing a hydraulic drive device and an area limited excavation control device for a hydraulic excavator according to the second embodiment of the present invention.

  In the above embodiment, the boom pipe control valve 22 and the arm pipe control valve 24 are provided as the pipe break control valves. However, only the boom pipe control valve 22 may be provided as the pipe break control valve. . Further, as the operator operation detecting device 31, a pressure detector that detects the operation pilot pressure of the bucket cloud and the bucket dump is provided, and the electromagnetic proportional valve that corrects the operation pilot pressure of the bucket cloud and the bucket dump is used as an electromagnetic proportional valve for the correction operation. May be provided. FIG. 15 shows such an embodiment.

  That is, in the embodiment shown in FIG. 15, the area restriction control device does not include the arm pipe control valve 24. In addition, the bucket pilot lines 13a and 13b include pressure detectors 57a and 57b that detect the operation pilot pressure of the bucket cloud and the bucket dump, and an electromagnetic proportional valve 58a that corrects the operation pilot pressure of the bucket cloud and the bucket dump. 58b is provided.

  In this embodiment, the cylinder speed calculation unit 43a (first calculation unit) of the control unit 35 breaks the boom piping only for the first correlation table for raising the boom and the first correlation table for lowering the boom. Two types of first correlation tables are stored in the ROM 35c according to whether or not the control valve 22 is mounted, and the boom pipe breakage is determined according to the flag information indicating whether or not the pipe breakage control valve 22 is set in the information management device 36. By selecting the first correlation table F1 when the control valve 22 is mounted, the calculation process by the first correlation table is corrected, and the drive speed of the boom cylinder 3a is calculated.

  Further, the operation signal control value calculation unit 43c (third calculation unit) is provided with the boom pipe break control valve 22 mounted only on the second correlation table for raising the boom and the second correlation table for lowering the boom. Two types of second correlation tables are stored in the ROM 35c according to the presence / absence, and the boom pipe break control valve 22 is mounted according to the flag information indicating whether the pipe break control valve 22 is set or not set in the information management device 36. By selecting the second correlation table F3 in this case, the calculation processing by the second correlation table is corrected, and the control value of the operation pilot pressure for raising or lowering the boom is calculated.

  The cylinder speed calculation unit 43a of the control unit 35 includes a first correlation table (correlation) between the bucket cloud operation pilot pressure (operation signal) detected by the pressure detector 57a and the bucket cloud driving speed of the bucket cylinder 3c; It has a first correlation table (correlation) between the bucket pilot operation pilot pressure (operation signal) detected by the pressure detector 57b and the bucket dump drive speed of the bucket cylinder 3c, and the bucket operation device 4c of the operator. The driving speed (bucket cylinder speed) of the bucket cylinder 3c by the above operation is calculated. The operation signal control value calculation unit 43c includes a second correlation table (correlation function) between the bucket cloud driving speed of the bucket cylinder 3c and the bucket cloud operation pilot pressure (operation signal), and the bucket dump driving speed of the bucket cylinder 3c. It has a second correlation table (correlation function) with the operation pilot pressure (operation signal) of the bucket dump, and calculates the control value of the operation pilot pressure (operation signal) of the bucket cloud and the bucket dump. However, since the pipe break control valve is not attached to the bucket cylinder 3c, one type of correlation table is stored in the ROM 35c as the first and second correlation tables.

  Other configurations and functions are the same as those in the first embodiment.

Also in this embodiment configured as described above, in the arm cloud operation, when the bucket tip speed is decelerated by the correction operation by raising the boom, the operation signal control value calculation unit 43c determines whether or not the pipe breakage control valve 22 is mounted. By calculating the control value of the boom raising operation pilot pressure by correcting the calculation processing by the second correlation table according to the flag information, the target excavation is performed by the area limited excavation control regardless of whether the pipe breakage control valve is installed. Control accuracy in shaping the surface can be ensured.
The

  Further, in the boom lowering operation, the cylinder speed calculation unit 43a calculates the driving speed of the boom cylinder 3a by correcting the calculation process by the first correlation table according to the flag information indicating whether the pipe breakage control valve 22 is mounted, and the operation. Similarly, by calculating the control value of the boom lowering operation pilot pressure by correcting the calculation processing by the second correlation table in accordance with the flag information of whether or not the pipe breakage control valve 22 is mounted in the signal control value calculation unit 43c, Regardless of whether or not the pipe breakage control valve is mounted, it is possible to ensure the control accuracy when shaping the target excavation surface by the area limited excavation control.

  Furthermore, pressure detectors 57a and 57b that detect the operation pilot pressure of the bucket cloud and bucket dump and electromagnetic proportional valves 58a and 58b that correct the operation pilot pressure of the bucket cloud and bucket dump are provided. High area limited excavation control is possible.

~ Others ~
1. In the above embodiment, the present invention is applied to a hydraulic excavator having a hydraulic pilot type operating device and a flow control valve. However, the operating device generates an electric signal, and the flow control valve is an electric type that can be switched by the electric signal. May be. In this case, instead of the electromagnetic proportional valve control unit 44, the boom lowering operation signal (electric signal) generated by the boom operation device and the boom operation device 4a operation signal (electric signal) calculated by the operation signal control value calculation unit 43c are used. The control value with the larger control value is selected, and the selected value is converted into an electric signal and output.

  2. In the above embodiment, as a method for generating the cylinder speed control value of the area limited excavation control, as shown in FIG. 10, a component perpendicular to the target excavation surface L of the bucket tip speed based on the distance D from the target excavation surface. The limit value a is calculated, and the control value of the control cylinder speed is calculated using the limit value a. This is an example. For example, by using a function having the distance D as a variable, a component perpendicular to the target excavation surface of the bucket tip speed is reduced according to the distance D, and a control value of the cylinder speed is calculated. The cylinder speed control value may be calculated.

  3. In the above embodiment, the applied hydraulic drive device is a closed center system having closed center type flow control valves 5a to 5f. However, even if it is an open center system using an open center type flow control valve. Good.

  4). In the above embodiment, the present invention is applied to the hydraulic excavator (working machine) including the pipe break control valves 22 and 24 shown in FIG. 15, but there are various types of pipe break control valves, and the flow resistance The present invention may be applied to a hydraulic excavator provided with the pipe breakage control valve shown in FIG.

  5. In the above embodiment, the case where the work machine is a hydraulic excavator has been described. However, the present invention is applicable to work machines other than hydraulic excavators as long as the area limited excavation control is performed by a work machine including an articulated work device. May be applied.

  6). The configuration may include a satellite communication antenna, and the region limited excavation control may be performed by calculating the position of the excavator in the global coordinate system.

  7). In order to detect the position of the working device 120, the rotation fulcrum is provided with an angle sensor. Instead of this, a plurality of stroke detectors for detecting the stroke amount of the hydraulic cylinder, booms, arms, and buckets are used. An inclination angle detector that detects the inclination angle may be used. Further, although the control target has been described as the tip of the bucket, this is merely an example, and a portion of the work device 120 that is the shortest distance from the target excavation surface may be the control target.

2 Hydraulic pump 3a Boom cylinder 3a1 Bottom side chamber 3a2 Rod side chamber 3b Arm cylinder 3b1 Bottom side chamber 3b2 Rod side chamber 3c Bucket cylinder 4a Boom operating device 4b Arm operating device 4c Bucket operating device 5a Boom flow control valve 5b Arm flow control Valve 5c Bucket flow control valve 8 Working device attitude detection devices 8a to 8c Angle detector 8d Tilt detectors 21a and 21b First and second hydraulic lines 22 Boom pipe breakage control valves 23a and 23b Third and fourth Hydraulic pipeline 24 Arm pipe break control valve 31 Operator operation detection device 33 Shuttle valve 34 Display device 35 Control unit 35c ROM (storage device)
36 Information management device (information setting device)
41 working device attitude calculation unit 42 target excavation surface calculation unit 43 area limited excavation control calculation unit 43a cylinder speed calculation unit (first calculation unit)
43a1 selection unit 43a2 calculation unit 43b restriction control calculation unit (second calculation unit)
43c Operation signal control value calculation unit (third calculation unit)
43c1 Selection unit 43c2 Calculation unit 44 Electromagnetic proportional valve control units 51a, 51b, 52a, 52b, 57a, 57b Pressure detectors 54a, 54b, 55a, 55b, 58a, 58b Electromagnetic proportional valve 110 Car body 111 Lower traveling body 112 Upper swing body 120 Working device 121 Boom 122 Arm 123 Bucket F1 First correlation table (with pipe break control valve)
F2 First correlation table (without pipe break control valve)
F3 Second correlation table (with pipe break control valve)
F4 Second correlation table (without pipe break control valve)
L Target excavation surface

Claims (5)

An articulated working device;
A plurality of hydraulic cylinders for driving the working device;
A plurality of operating devices for instructing the operation of the working device;
In a work machine including a plurality of flow rate control valves that are driven by operation signals of the plurality of operation devices and control a flow of pressure oil supplied to the plurality of hydraulic cylinders,
An area limited excavation control device for controlling the work device so as not to enter below the target excavation surface;
An information setting device for setting information related to the presence or absence of a pipe breakage control valve connected to at least one of a plurality of hydraulic pipe lines connecting the plurality of hydraulic cylinders and the plurality of flow rate control valves, respectively; Prepared,
The area limited excavation control device is:
The drive speeds of the plurality of hydraulic cylinders corresponding to the plurality of specific operation devices are calculated from the operation signals of at least some of the plurality of operation devices among the plurality of operation devices using the respective first correlation functions. A first computing unit that performs
Based on the drive speeds of the plurality of hydraulic cylinders calculated by the first calculation unit and the positional relationship between the work device and the target excavation surface, the work device is prevented from entering below the target excavation surface. A second calculation unit for calculating a control value of a drive speed of a plurality of specific hydraulic cylinders of at least a part of the plurality of hydraulic cylinders driving the device;
Control of operation signals of a plurality of operation devices corresponding to the plurality of specific hydraulic cylinders using respective second correlation functions from control values of driving speeds of the plurality of specific hydraulic cylinders calculated by the second calculation unit. A third calculation unit for calculating a value;
A plurality of operations corresponding to the plurality of specific hydraulic cylinders so that the work device does not enter below the target excavation surface based on control values of operation signals of the plurality of operation devices calculated by the third calculation unit. An operation signal correction device for correcting the operation signal of the device,
The plurality of hydraulic cylinders corresponding to the plurality of specific operation devices include a hydraulic cylinder related to the pipe breakage control valve, and the first calculation unit is a hydraulic pressure related to the pipe breakage control valve as the first correlation function. Including a specific first correlation function for the cylinder;
The plurality of specific hydraulic cylinders include a hydraulic cylinder related to the pipe breakage control valve, and the third calculation unit uses a second specific function for the hydraulic cylinder related to the pipe breakage control valve as the second correlation function. Including a correlation function,
The first calculation unit and the third calculation unit receive information related to whether or not the pipe breakage control valve is mounted from the information setting device, and the specific calculation unit according to whether or not the pipe breakage control valve is mounted. Compensation of arithmetic processing by one correlation function and the specific second correlation function, and control of the driving speed of the hydraulic cylinder related to the pipe break control valve and the operation signal of the operating device corresponding to the hydraulic cylinder related to the pipe break control valve A work machine characterized by calculating each value. The work machine according to claim 1,
The working device includes a boom and an arm,
The pipe break control valve includes a boom pipe break control valve and an arm pipe break control valve,
The plurality of specific operation devices include a boom operation device that instructs the operation of the boom and an arm operation device that instructs the operation of the arm,
The specific first correlation function of the first calculation unit includes a first correlation function for a boom and a first correlation function for an arm,
The first calculation unit uses the first correlation function for the boom and the first correlation function for the arm according to whether or not the boom pipe breakage control valve and the arm pipe breakage control valve are mounted. A work machine characterized in that it corrects arithmetic processing performed. The work machine according to claim 1,
The working device includes a boom and an arm,
The plurality of hydraulic cylinders include a boom cylinder that drives the boom and an arm cylinder that drives the arm,
The pipe break control valve includes a boom pipe break control valve and an arm pipe break control valve,
The plurality of specific hydraulic cylinders include the boom cylinder and the arm cylinder;
The specific second correlation function of the third calculation unit includes a second correlation function for a boom and a second correlation function for an arm,
The third calculation unit uses the second correlation function for the boom and the second correlation function for the arm according to whether or not the boom pipe breakage control valve and the arm pipe breakage control valve are mounted. A work machine characterized in that it corrects arithmetic processing performed. The work machine according to claim 1,
The first calculation unit and the second calculation unit prepare two types of correlation functions as the specific first correlation function and the specific second correlation function, respectively, depending on whether or not the pipe breakage control valve is mounted. A corresponding correlation function is selected from the two types of correlation functions depending on whether or not the pipe breakage control valve is installed, and using the selected correlation function, the driving speed of the hydraulic cylinder and the operation signal of the operating device are selected. A work machine that calculates a control value to correct a calculation process using the specific first correlation function and the specific second correlation function according to whether or not the pipe breakage control valve is mounted. The work machine according to claim 1,
The work machine characterized in that the information setting device is an information management device that inputs and sets information relating to whether or not the pipe breakage control valve is mounted as flag information.

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