Excavator

Abstract

To provide an excavator capable of automatically vibrating bucket with a simpler configuration.SOLUTION: An excavator 100 includes: an undercarriage 1; an upper revolving body 3 mounted to the undercarriage 1 rotatably; an attachment AT including an arm 5 and a bucket 6 to be attached to the upper revolving body 3; a manipulator 26 for manipulating the attachment AT. The excavator 100 is configured to operate in a vibration mode including a gravel mode.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a shovel as an excavator. [Background technology]

[0002] Conventionally, a vibration generating adapter for an excavator is known that is attached between the arm and bucket of the excavator to generate vibrations (see, for example, Patent Document 1). This vibration generating adapter is configured, for example, to apply vibrations to the bucket using a vibration generating mechanism, and to compact the soil while pressing the back surface of the bucket against the soil. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-038514 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, an excavator for carrying out the above-mentioned compaction work needs to have a vibration generating adapter attached between the arm and the bucket, which makes the structure complicated.

[0005] Therefore, it is desirable to provide a shovel that can automatically vibrate the bucket with a simpler configuration. [Means for solving the problem]

[0006] The shovel according to an embodiment of the present invention includes a lower traveling body, an upper rotating body rotatably mounted on the lower traveling body, and a shovel mounted on the upper rotating body. boom, An attachment including an arm and a bucket, and an operation for operating the attachment lever and, A switch provided at the tip of the operating lever; A shovel having The operating lever includes an arm operating lever for operating the arm, and is configured so that an operator can operate the arm while pressing the switch. When the switch is pressed, the shovel: Gravel spreading mode and gravel removal mode and configured to operate in a vibration mode including In the gravel spreading mode, when an operator operates the operation lever while pressing the switch, the shovel operates the arm or the boom in accordance with the amount of operation of the operation lever while automatically opening and closing the bucket, and when the operator operates the operation lever without pressing the switch, the shovel operates the arm or the boom in accordance with the amount of operation of the operation lever without automatically opening or closing the bucket. In the gravel removal mode, when the operator does not operate the arm operation lever while pressing the switch, the shovel automatically opens and closes the bucket and automatically opens and closes the arm, and when the operator operates the arm operation lever while pressing the switch, the shovel operates the arm in accordance with the amount of operation of the arm operation lever while automatically opening and closing the bucket. . Effect of the Invention

[0007] The above-described shovel can automatically vibrate the bucket with a simpler configuration. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a side view of a shovel according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a top view of the excavator of FIG. 1. [Diagram 3] FIG. 2 is a diagram showing a configuration example of a hydraulic system mounted on the excavator shown in FIG. [Figure 4A] FIG. 1 is a diagram of a portion of the hydraulic system for operation of the arm cylinder. [Figure 4B] FIG. 2 is a diagram of a portion of the hydraulic system for the boom cylinder. [Figure 4C] FIG. 2 is a diagram of a portion of the hydraulic system for a bucket cylinder. [Figure 4D] FIG. 2 is a diagram of a portion of a hydraulic system for a swing hydraulic motor. [Diagram 5] FIG. 2 illustrates an example of the configuration of a controller. [Figure 6] 10 is a flowchart showing an example of the flow of a mode switching process. [Figure 7] 13 is a flowchart showing an example of the flow of a bucket adjustment process. [Figure 8] 13 is a flowchart showing an example of the flow of an arm adjustment process. [Figure 9] FIG. 11 is a diagram showing a transition over time of an opening command and a closing command for a bucket and a bucket angle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First, a shovel 100 as an excavator according to an embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a side view of the shovel 100, and Figure 2 is a top view of the shovel 100.

[0010] In this embodiment, the lower traveling structure 1 of the excavator 100 includes a crawler 1C. The crawler 1C is driven by a traveling hydraulic motor 2M as a traveling actuator mounted on the lower traveling structure 1. Specifically, the crawler 1C includes a left crawler 1CL and a right crawler 1CR. The left crawler 1CL is driven by a left traveling hydraulic motor 2ML, and the right crawler 1CR is driven by a right traveling hydraulic motor 2MR.

[0011] An upper rotating body 3 is rotatably mounted on the lower traveling body 1 via a rotating mechanism 2. The rotating mechanism 2 is driven by a rotating hydraulic motor 2A serving as a rotating actuator mounted on the upper rotating body 3. However, the rotating actuator may be a rotating motor-generator serving as an electric actuator.

[0012] A boom 4 is attached to the upper rotating body 3. An arm 5 is attached to the tip of the boom 4, and a bucket 6 is attached to the tip of the arm 5 as an end attachment. The boom 4, the arm 5, and the bucket 6 constitute an attachment AT, which is an example of an attachment. The boom 4 is driven by a boom cylinder 7, the arm 5 is driven by an arm cylinder 8, and the bucket 6 is driven by a bucket cylinder 9. The boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 constitute an attachment actuator. In the example shown in Figs. 1 and 2, the bucket 6 is an excavation bucket, but it may be a skeleton bucket (gravel removal bucket). The bucket 6 may also be equipped with a bucket tilt mechanism.

[0013] The upper rotating body 3 is provided with a cabin 10 as a driver's cab, and is equipped with a power source such as an engine 11. An operation device 26, a controller 30, an operation method switching device SD, etc. are provided inside the cabin 10. In addition, a spatial recognition device 70, etc. are attached to the upper rotating body 3. For convenience, in this specification, the side of the upper rotating body 3 to which the attachment AT is attached is referred to as the front, and the side to which the counterweight is attached is referred to as the rear.

[0014] The spatial recognition device 70 is configured to recognize an object present in a three-dimensional space around the shovel 100. The spatial recognition device 70 may be configured to calculate a distance from the spatial recognition device 70 or the shovel 100 to the recognized object. The spatial recognition device 70 includes, for example, an ultrasonic sensor, a millimeter wave radar, an imaging device, a LIDAR, a distance image sensor, an infrared sensor, or any combination thereof. The imaging device is, for example, a monocular camera or a stereo camera. In this embodiment, the spatial recognition device 70 includes a forward sensor 70F attached to the front end of the upper surface of the cabin 10, a rear sensor 70B attached to the rear end of the upper surface of the upper rotating body 3, a left sensor 70L attached to the left end of the upper surface of the upper rotating body 3, and a right sensor 70R attached to the right end of the upper surface of the upper rotating body 3. An upward sensor that recognizes an object present in the space above the upper rotating body 3 may be attached to the shovel 100.

[0015] The operating device 26 is a device used by an operator to operate the actuator. The operating device 26 includes, for example, an operating lever and an operating pedal. The actuator includes at least one of a hydraulic actuator and an electric actuator.

[0016] The operation mode switching device SD is configured to be able to switch the operation mode of the operation lever. For example, the operation mode switching device SD includes a push button switch provided on the right console in the cabin 10, and is configured to be able to switch the operation mode of the operation lever between a first operation mode and a second operation mode each time the push button switch is pressed. For example, the first operation mode is configured such that when the left operation lever 26L (see FIG. 3) is tilted forward, the arm 5 is opened, when the left operation lever 26L is tilted backward, the arm 5 is closed, when the left operation lever 26L is tilted left, a left turn is performed, and when the left operation lever 26L is tilted right, a right turn is performed. The first operation method is configured so that when the right operation lever 26R (see FIG. 3) is tilted forward, the boom 4 is lowered, when the right operation lever 26R is tilted rearward, the boom 4 is raised, when the right operation lever 26R is tilted leftward, the bucket 6 is closed, and when the right operation lever 26R is tilted rightward, the bucket 6 is opened. On the other hand, the second operation method is configured so that when the left operation lever 26L (see FIG. 3) is tilted forward, a right turn is performed, when the left operation lever 26L is tilted rearward, a left turn is performed, when the left operation lever 26L is tilted leftward, the arm 5 is opened, and when the left operation lever 26L is tilted rightward, the arm 5 is closed.

[0017] An operator of the shovel 100 may, for example, select the first operation method when performing excavation work using an excavation bucket, and may select the second operation method when performing gravel removal work using a skeleton bucket (gravel removal bucket).

[0018] The controller 30 is a control device for controlling the shovel 100. In this embodiment, the controller 30 is configured with a computer including a CPU, a volatile storage device, a nonvolatile storage device, and the like. The controller 30 reads out a program corresponding to each function from the nonvolatile storage device, loads it into the volatile storage device, and causes the CPU to execute the corresponding process. Each function includes, for example, a machine guidance function that guides the operator in manually operating the shovel 100, and a machine control function that supports the operator in manually operating the shovel 100 or automatically or autonomously operates the shovel 100. The controller 30 may include a contact avoidance function that automatically or autonomously operates or stops the shovel 100 to avoid contact between the shovel 100 and an object present within a monitoring range around the shovel 100. Monitoring of objects around the shovel 100 is performed not only within the monitoring range but also outside the monitoring range.

[0019] Next, a configuration example of a hydraulic system mounted on the shovel 100 will be described with reference to Fig. 3. Fig. 3 is a diagram showing a configuration example of a hydraulic system mounted on the shovel 100. In Fig. 3, a mechanical power transmission system, a hydraulic oil line, a pilot line, and an electric control system are indicated by double lines, solid lines, dashed lines, and dotted lines, respectively.

[0020] The hydraulic system of the excavator 100 mainly includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve unit 17, an operating device 26, a discharge pressure sensor 28, an operation sensor 29, a controller 30, and the like.

[0021] In FIG. 3, the hydraulic system is configured to circulate hydraulic oil from a main pump 14 driven by an engine 11 through a center bypass line 40 or a parallel line 42 to a hydraulic oil tank.

[0022] The engine 11 is a drive source of the excavator 100. In this embodiment, the engine 11 is, for example, a diesel engine that operates to maintain a predetermined rotation speed. An output shaft of the engine 11 is connected to input shafts of the main pump 14 and the pilot pump 15.

[0023] The main pump 14 is configured to supply hydraulic oil via a hydraulic oil line to the control valve unit 17. In this embodiment, the main pump 14 is a swash plate type variable displacement hydraulic pump.

[0024] The regulator 13 is configured to be able to control the discharge amount of the main pump 14. In this embodiment, the regulator 13 controls the discharge amount of the main pump 14 by adjusting the swash plate tilt angle of the main pump 14 in response to a control command from the controller 30.

[0025] The pilot pump 15 is an example of a pilot pressure generating device, and is configured to be able to supply hydraulic oil to hydraulic control devices via a pilot line. In this embodiment, the pilot pump 15 is a fixed displacement hydraulic pump. However, the pilot pressure generating device may be realized by the main pump 14. That is, the main pump 14 may have a function of supplying hydraulic oil to various hydraulic control devices via a pilot line, in addition to a function of supplying hydraulic oil to the control valve unit 17 via a hydraulic oil line. In this case, the pilot pump 15 may be omitted.

[0026] The control valve unit 17 is a hydraulic control device that controls the hydraulic system in the excavator 100. In this embodiment, the control valve unit 17 includes control valves 171 to 176. The control valve 175 includes a control valve 175L and a control valve 175R, and the control valve 176 includes a control valve 176L and a control valve 176R. The control valve unit 17 is configured to selectively supply hydraulic oil discharged by the main pump 14 to one or more hydraulic actuators through the control valves 171 to 176. The control valves 171 to 176 control, for example, the flow rate of hydraulic oil flowing from the main pump 14 to the hydraulic actuators and the flow rate of hydraulic oil flowing from the hydraulic actuators to a hydraulic oil tank. The hydraulic actuators include a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a left traveling hydraulic motor 2ML, a right traveling hydraulic motor 2MR, and a swing hydraulic motor 2A.

[0027] The operating device 26 is configured to allow an operator to operate the actuator. In this embodiment, the operating device 26 includes a hydraulic actuator operating device configured to allow an operator to operate the hydraulic actuator. Specifically, the hydraulic actuator operating device is configured to supply hydraulic oil discharged from the pilot pump 15 to the pilot port of the corresponding control valve in the control valve unit 17 via a pilot line. The pressure of the hydraulic oil supplied to each pilot port (pilot pressure) is a pressure according to the operation direction and operation amount of the operating device 26 corresponding to each hydraulic actuator.

[0028] The discharge pressure sensor 28 is configured to detect the discharge pressure of the main pump 14. In this embodiment, the discharge pressure sensor 28 outputs the detected value to the controller 30.

[0029] The operation sensor 29 is configured to detect the content of an operation of the operation device 26 by an operator. In this embodiment, the operation sensor 29 detects the operation direction and operation amount of the operation device 26 corresponding to each actuator, and outputs the detected values ​​to the controller 30.

[0030] The main pump 14 includes a left main pump 14L and a right main pump 14R. The left main pump 14L circulates hydraulic oil to a hydraulic oil tank via a left center bypass line 40L or a left parallel line 42L, and the right main pump 14R circulates hydraulic oil to a hydraulic oil tank via a right center bypass line 40R or a right parallel line 42R.

[0031] The left center bypass line 40L is a hydraulic oil line that passes through control valves 171, 173, 175L, and 176L arranged in the control valve unit 17. The right center bypass line 40R is a hydraulic oil line that passes through control valves 172, 174, 175R, and 176R arranged in the control valve unit 17.

[0032] The control valve 171 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the left traveling hydraulic motor 2ML and to discharge the hydraulic oil discharged by the left traveling hydraulic motor 2ML to the hydraulic oil tank.

[0033] The control valve 172 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the right traveling hydraulic motor 2MR and to discharge the hydraulic oil discharged by the right traveling hydraulic motor 2MR to the hydraulic oil tank.

[0034] The control valve 173 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the swing hydraulic motor 2A and to discharge the hydraulic oil discharged by the swing hydraulic motor 2A to the hydraulic oil tank.

[0035] The control valve 174 is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the bucket cylinder 9 and to discharge the hydraulic oil in the bucket cylinder 9 to the hydraulic oil tank.

[0036] The control valve 175L is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the boom cylinder 7. The control valve 175R is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the boom cylinder 7 and to discharge the hydraulic oil in the boom cylinder 7 to the hydraulic oil tank.

[0037] The control valve 176L is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the left main pump 14L to the arm cylinder 8 and to discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

[0038] The control valve 176R is a spool valve that switches the flow of hydraulic oil to supply the hydraulic oil discharged by the right main pump 14R to the arm cylinder 8 and to discharge the hydraulic oil in the arm cylinder 8 to the hydraulic oil tank.

[0039] The left parallel conduit 42L is a hydraulic oil line that runs parallel to the left center bypass conduit 40L. The left parallel conduit 42L can supply hydraulic oil to a more downstream control valve when the flow of hydraulic oil through the left center bypass conduit 40L is restricted or blocked by any of the control valves 171, 173, and 175L. The right parallel conduit 42R is a hydraulic oil line that runs parallel to the right center bypass conduit 40R. The right parallel conduit 42R can supply hydraulic oil to a more downstream control valve when the flow of hydraulic oil through the right center bypass conduit 40R is restricted or blocked by any of the control valves 172, 174, and 175R.

[0040] The regulator 13 includes a left regulator 13L and a right regulator 13R. The left regulator 13L controls the discharge amount of the left main pump 14L by adjusting the swash plate tilt angle of the left main pump 14L according to the discharge pressure of the left main pump 14L. Specifically, the left regulator 13L adjusts the swash plate tilt angle of the left main pump 14L in response to an increase in the discharge pressure of the left main pump 14L, for example, to reduce the discharge amount. The same is true for the right regulator 13R. This is to prevent the absorption power (absorption horsepower) of the main pump 14, which is expressed by the product of the discharge pressure and the discharge amount, from exceeding the output power (output horsepower) of the engine 11.

[0041] The operating device 26 includes a left operating lever 26L, a right operating lever 26R, and a travel lever 26D. The travel lever 26D includes a left traveling lever 26DL and a right traveling lever 26DR.

[0042] The left operating lever 26L is used for the rotation operation and the operation of the arm 5. When the left operating lever 26L is operated in the forward / backward direction, the hydraulic oil discharged by the pilot pump 15 is used to introduce a control pressure according to the amount of lever operation into the pilot port of the control valve 176. When the left operating lever 26L is operated in the left / right direction, the hydraulic oil discharged by the pilot pump 15 is used to introduce a control pressure according to the amount of lever operation into the pilot port of the control valve 173.

[0043] Specifically, when the left operating lever 26L is operated in the arm closing direction, it introduces hydraulic oil to the right pilot port of the control valve 176L and introduces hydraulic oil to the left pilot port of the control valve 176R. When the left operating lever 26L is operated in the arm opening direction, it introduces hydraulic oil to the left pilot port of the control valve 176L and introduces hydraulic oil to the right pilot port of the control valve 176R. When the left operating lever 26L is operated in the left turning direction, it introduces hydraulic oil to the left pilot port of the control valve 173, and when operated in the right turning direction, it introduces hydraulic oil to the right pilot port of the control valve 173.

[0044] In the example shown in FIG. 3, the left operating lever 26L functions as an arm operating lever when operated in the forward / rearward direction, and functions as a turning operating lever when operated in the left / right direction.

[0045] The right operating lever 26R is used to operate the boom 4 and the bucket 6. When the right operating lever 26R is operated in the forward / backward direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 175. When the right operating lever 26R is operated in the left / right direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the amount of lever operation into the pilot port of the control valve 174.

[0046] Specifically, the right operating lever 26R introduces hydraulic oil to the left pilot port of the control valve 175R when operated in the boom lowering direction. Furthermore, the right operating lever 26R introduces hydraulic oil to the right pilot port of the control valve 175L and also introduces hydraulic oil to the left pilot port of the control valve 175R when operated in the boom raising direction. Furthermore, the right operating lever 26R introduces hydraulic oil to the right pilot port of the control valve 174 when operated in the bucket closing direction, and introduces hydraulic oil to the left pilot port of the control valve 174 when operated in the bucket opening direction.

[0047] In the example shown in FIG. 3, the right operating lever 26R functions as a boom operating lever when operated in the forward / rearward direction, and functions as a bucket operating lever when operated in the left / right direction.

[0048] The travel lever 26D is used to operate the crawler 1C. Specifically, the left travel lever 26DL is used to operate the left crawler 1CL. It may be configured to be interlocked with the left travel pedal. When the left travel lever 26DL is operated in the forward / backward direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 171. The right travel lever 26DR is used to operate the right crawler 1CR. It may be configured to be interlocked with the right travel pedal. When the right travel lever 26DR is operated in the forward / backward direction, it uses the hydraulic oil discharged by the pilot pump 15 to introduce a control pressure corresponding to the lever operation amount into the pilot port of the control valve 172.

[0049] The discharge pressure sensor 28 includes a discharge pressure sensor 28L and a discharge pressure sensor 28R. The discharge pressure sensor 28L detects the discharge pressure of the left main pump 14L and outputs the detected value to the controller 30. The same applies to the discharge pressure sensor 28R.

[0050] The operation sensor 29 includes operation sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29DR. The operation sensor 29LA detects the content of the operation of the left operation lever 26L by the operator in the forward / rearward direction, and outputs the detected value to the controller 30. The content of the operation includes, for example, the lever operation direction, the lever operation amount (lever operation angle), etc.

[0051] Similarly, the operation sensor 29LB detects the operation of the left operating lever 26L in the left-right direction by the operator, and outputs the detected value to the controller 30. The operation sensor 29RA detects the operation of the right operating lever 26R in the forward-backward direction by the operator, and outputs the detected value to the controller 30. The operation sensor 29RB detects the operation of the right operating lever 26R in the left-right direction by the operator, and outputs the detected value to the controller 30. The operation sensor 29DL detects the operation of the left traveling lever 26DL in the forward-backward direction by the operator, and outputs the detected value to the controller 30. The operation sensor 29DR detects the operation of the right traveling lever 26DR in the forward-backward direction by the operator, and outputs the detected value to the controller 30.

[0052] The controller 30 receives the output of the operation sensor 29, and outputs a control command to the regulator 13 as necessary, thereby changing the discharge volume of the main pump 14. The controller 30 also receives the output of the control pressure sensor 19 provided upstream of the orifice 18, and outputs a control command to the regulator 13 as necessary, thereby changing the discharge volume of the main pump 14. The orifice 18 includes a left orifice 18L and a right orifice 18R, and the control pressure sensor 19 includes a left control pressure sensor 19L and a right control pressure sensor 19R.

[0053] The left center bypass pipe 40L is provided with a left throttle 18L between the most downstream control valve 176L and the hydraulic oil tank. Therefore, the flow of hydraulic oil discharged by the left main pump 14L is restricted by the left throttle 18L. The left throttle 18L generates a control pressure for controlling the left regulator 13L. The left control pressure sensor 19L is a sensor for detecting this control pressure, and outputs the detected value to the controller 30. The controller 30 controls the discharge amount of the left main pump 14L by adjusting the swash plate tilt angle of the left main pump 14L according to this control pressure. The controller 30 reduces the discharge amount of the left main pump 14L as this control pressure increases, and increases the discharge amount of the left main pump 14L as this control pressure decreases. The discharge amount of the right main pump 14R is also controlled in a similar manner.

[0054] Specifically, as shown in FIG. 3, in the case of a standby state in which none of the hydraulic actuators in the excavator 100 are operated, the hydraulic oil discharged by the left main pump 14L passes through the left center bypass pipe 40L and reaches the left throttle 18L. Then, the flow of the hydraulic oil discharged by the left main pump 14L increases the control pressure generated upstream of the left throttle 18L. As a result, the controller 30 reduces the discharge amount of the left main pump 14L to the allowable minimum discharge amount, suppressing the pressure loss (pumping loss) when the discharged hydraulic oil passes through the left center bypass pipe 40L. On the other hand, when any of the hydraulic actuators is operated, the hydraulic oil discharged by the left main pump 14L flows into the hydraulic actuator to be operated through the control valve corresponding to the hydraulic actuator to be operated. Then, the flow of the hydraulic oil discharged by the left main pump 14L reduces or eliminates the amount of hydraulic oil reaching the left throttle 18L, lowering the control pressure generated upstream of the left throttle 18L. As a result, the controller 30 increases the discharge rate of the left main pump 14L to circulate sufficient hydraulic oil to the hydraulic actuator to be operated, ensuring the drive of the hydraulic actuator to be operated. The controller 30 also controls the discharge rate of the right main pump 14R in a similar manner.

[0055] With the above-described configuration, the hydraulic system of Fig. 3 can suppress unnecessary energy consumption in the main pump 14 in a standby state. The unnecessary energy consumption includes pumping loss caused in the center bypass pipe 40 by the hydraulic oil discharged from the main pump 14. Furthermore, when operating a hydraulic actuator, the hydraulic system of Fig. 3 can reliably supply necessary and sufficient hydraulic oil from the main pump 14 to the hydraulic actuator to be operated.

[0056] Next, a configuration for the controller 30 to operate the actuators by the machine control function will be described with reference to Fig. 4A to Fig. 4D. Fig. 4A to Fig. 4D are diagrams showing parts of the hydraulic system. Specifically, Fig. 4A is a diagram showing the hydraulic system part related to the operation of the arm cylinder 8, and Fig. 4B is a diagram showing the hydraulic system part related to the operation of the boom cylinder 7. Fig. 4C is a diagram showing the hydraulic system part related to the operation of the bucket cylinder 9, and Fig. 4D is a diagram showing the hydraulic system part related to the operation of the swing hydraulic motor 2A.

[0057] 4A to 4D, the hydraulic system includes a proportional valve 31. The proportional valve 31 includes proportional valves 31AL to 31DL and 31AR to 31DR.

[0058] The proportional valve 31 functions as a control valve for machine control. The proportional valve 31 is disposed in a pipe connecting the pilot pump 15 and a pilot port of a corresponding control valve in the control valve unit 17, and is configured to be able to change the flow passage area of ​​the pipe. In this embodiment, the proportional valve 31 operates in response to a control command output by the controller 30. Therefore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the pilot port of the corresponding control valve in the control valve unit 17 via the proportional valve 31, regardless of the operation of the operating device 26 by the operator. Then, the controller 30 can apply the pilot pressure generated by the proportional valve 31 to the pilot port of the corresponding control valve.

[0059] With this configuration, the controller 30 can operate the hydraulic actuator corresponding to a specific operating device 26 even when no operation is being performed on that specific operating device 26. Furthermore, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to that specific operating device 26 even when an operation is being performed on that specific operating device 26.

[0060] For example, as shown in FIG. 4A, the left operating lever 26L is used to operate the arm 5. Specifically, the left operating lever 26L uses hydraulic oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the forward / rearward direction to the pilot port of the control valve 176. More specifically, when the left operating lever 26L is operated in the arm closing direction (rearward direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R. Also, when the left operating lever 26L is operated in the arm opening direction (forward direction), the left operating lever 26L applies a pilot pressure corresponding to the operation amount to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R.

[0061] An operating lever, which is one of the operating devices 26, is provided with a switch NS. Specifically, a left switch NSL is provided on the left operating lever 26L, and a right switch NSR is provided on the right operating lever 26R. In this embodiment, the switch NS is a push button switch provided on the tip of the operating lever. The operator can operate the operating lever while pressing the switch NS. Note that either the left switch NSL or the right switch NSR may be omitted. Also, the switch NS may be provided in another position within the cabin 10.

[0062] The operation sensor 29LA detects the content of the operation of the left operation lever 26L in the forward / rearward direction by the operator, and outputs the detected value to the controller 30.

[0063] The proportional valve 31AL operates in response to a control command (current command) output by the controller 30. Then, it adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL. The proportional valve 31AR operates in response to a control command (current command) output by the controller 30. Then, it adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the proportional valve 31AR. The proportional valve 31AL can adjust the pilot pressure so that the control valve 176L and the control valve 176R can be stopped at any valve position. Similarly, the proportional valve 31AR can adjust the pilot pressure so that the control valve 176L and the control valve 176R can be stopped at any valve position.

[0064] With this configuration, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL in response to the arm closing operation by the operator. Also, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL, regardless of the arm closing operation by the operator. That is, the controller 30 can close the arm 5 in response to the arm closing operation by the operator or regardless of the arm closing operation by the operator.

[0065] Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the proportional valve 31AR in response to the arm opening operation by the operator. Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the proportional valve 31AR, regardless of the arm opening operation by the operator. That is, the controller 30 can open the arm 5 in response to the arm opening operation by the operator or regardless of the arm opening operation by the operator.

[0066] Furthermore, with this configuration, even if the operator is performing an arm closing operation, the controller 30 can, if necessary, reduce the pilot pressure acting on the closing side pilot ports of the control valve 176 (the left pilot port of the control valve 176L and the right pilot port of the control valve 176R) to forcibly stop the closing operation of the arm 5. The same applies to the case where the opening operation of the arm 5 is forcibly stopped when the operator is performing an arm opening operation.

[0067] Alternatively, even if the operator is performing an arm closing operation, the controller 30 may control the proportional valve 31AR as necessary to increase the pilot pressure acting on the opening pilot port of the control valve 176 (the right pilot port of the control valve 176L and the left pilot port of the control valve 176R) that is opposite the closing pilot port of the control valve 176, and forcibly return the control valve 176 to the neutral position, thereby forcibly stopping the closing operation of the arm 5. The same applies to the case where the opening operation of the arm 5 is forcibly stopped when the operator is performing an arm opening operation.

[0068] 4B to 4D, the same applies to the case where the operation of the boom 4 is forcibly stopped when the operator is performing a boom-raising or boom-lowering operation, the case where the operation of the bucket 6 is forcibly stopped when the operator is performing a bucket-closing or bucket-opening operation, and the case where the rotation operation of the upper rotating body 3 is forcibly stopped when the operator is performing a rotation operation. The same applies to the case where the traveling operation of the lower traveling body 1 is forcibly stopped when the operator is performing a traveling operation.

[0069] Also, as shown in FIG. 4B, the right operating lever 26R is used to operate the boom 4. Specifically, the right operating lever 26R uses hydraulic oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the forward / rearward direction to the pilot port of the control valve 175. More specifically, when the right operating lever 26R is operated in the boom-up direction (rearward direction), it applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R. Also, when the right operating lever 26R is operated in the boom-down direction (forward direction), it applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 175R.

[0070] The operation sensor 29RA detects the content of the operation of the right operating lever 26R in the forward / rearward direction by the operator, and outputs the detected value to the controller 30.

[0071] The proportional valve 31BL operates in response to a control command (current command) output by the controller 30. The proportional valve 31BL adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the proportional valve 31BL. The proportional valve 31BR operates in response to a control command (current command) output by the controller 30. The proportional valve 31BR adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR. The proportional valve 31BL can adjust the pilot pressure so that the control valves 175L and 175R can be stopped at any valve position. The proportional valve 31BR can adjust the pilot pressure so that the control valve 175R can be stopped at any valve position.

[0072] With this configuration, controller 30 can supply hydraulic oil discharged from pilot pump 15 to the right pilot port of control valve 175L and the left pilot port of control valve 175R via proportional valve 31BL in response to a boom-raising operation by the operator. Also, controller 30 can supply hydraulic oil discharged from pilot pump 15 to the right pilot port of control valve 175L and the left pilot port of control valve 175R via proportional valve 31BL, regardless of a boom-raising operation by the operator. In other words, controller 30 can raise boom 4 in response to a boom-raising operation by the operator or regardless of a boom-raising operation by the operator.

[0073] Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR in response to the boom lowering operation by the operator. Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR, regardless of the boom lowering operation by the operator. In other words, the controller 30 can lower the boom 4 in response to the boom lowering operation by the operator or regardless of the boom lowering operation by the operator.

[0074] 4C, the right operating lever 26R is also used to operate the bucket 6. Specifically, the right operating lever 26R utilizes hydraulic oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the left or right direction to the pilot port of the control valve 174. More specifically, when the right operating lever 26R is operated in the bucket closing direction (left direction), it applies a pilot pressure corresponding to the operation amount to the left pilot port of the control valve 174. Also, when the right operating lever 26R is operated in the bucket opening direction (right direction), it applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 174.

[0075] The operation sensor 29RB detects the content of the operation of the right operating lever 26R in the left or right direction by the operator, and outputs the detected value to the controller 30.

[0076] The proportional valve 31CL operates in response to a control command (current command) output by the controller 30. The proportional valve 31CR adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL. The proportional valve 31CR operates in response to a control command (current command) output by the controller 30. The proportional valve 31CR adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR. The proportional valve 31CL can adjust the pilot pressure so that the control valve 174 can be stopped at any valve position. Similarly, the proportional valve 31CR can adjust the pilot pressure so that the control valve 174 can be stopped at any valve position.

[0077] With this configuration, controller 30 can supply the hydraulic oil discharged by pilot pump 15 to the left pilot port of control valve 174 via proportional valve 31CL in response to a bucket closing operation by the operator. Moreover, controller 30 can supply the hydraulic oil discharged by pilot pump 15 to the left pilot port of control valve 174 via proportional valve 31CL, regardless of a bucket closing operation by the operator. In other words, controller 30 can close bucket 6 in response to a bucket closing operation by the operator or regardless of a bucket closing operation by the operator.

[0078] Furthermore, in response to a bucket opening operation by the operator, controller 30 can supply the hydraulic oil discharged by pilot pump 15 to the right pilot port of control valve 174 via proportional valve 31CR. Furthermore, regardless of a bucket opening operation by the operator, controller 30 can supply the hydraulic oil discharged by pilot pump 15 to the right pilot port of control valve 174 via proportional valve 31CR. In other words, controller 30 can open bucket 6 in response to a bucket opening operation by the operator or regardless of a bucket opening operation by the operator.

[0079] 4D, the left operation lever 26L is also used to operate the turning mechanism 2. Specifically, the left operation lever 26L uses hydraulic oil discharged by the pilot pump 15 to apply a pilot pressure corresponding to the operation in the left-right direction to the pilot port of the control valve 173. More specifically, when the left operation lever 26L is operated in the left turning direction (left direction), the left operation lever 26L applies a pilot pressure corresponding to the operation amount to the left pilot port of the control valve 173. Also, when the left operation lever 26L is operated in the right turning direction (right direction), the left operation lever 26L applies a pilot pressure corresponding to the operation amount to the right pilot port of the control valve 173.

[0080] The operation sensor 29LB detects the content of the operation of the left operation lever 26L in the left or right direction by the operator, and outputs the detected value to the controller 30.

[0081] The proportional valve 31DL operates in response to a control command (current command) output by the controller 30. The proportional valve 31DL adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL. The proportional valve 31DR operates in response to a control command (current command) output by the controller 30. The proportional valve 31DR adjusts the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR. The proportional valve 31DL can adjust the pilot pressure so that the control valve 173 can be stopped at any valve position. Similarly, the proportional valve 31DR can adjust the pilot pressure so that the control valve 173 can be stopped at any valve position.

[0082] With this configuration, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL in response to a left turning operation by the operator. Moreover, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL, regardless of the left turning operation by the operator. That is, the controller 30 can rotate the turning mechanism 2 left in response to a left turning operation by the operator or regardless of the left turning operation by the operator.

[0083] Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR in response to a right turning operation by the operator. Furthermore, the controller 30 can supply the hydraulic oil discharged by the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR, regardless of a right turning operation by the operator. That is, the controller 30 can rotate the turning mechanism 2 to the right in response to a right turning operation by the operator or regardless of a right turning operation by the operator.

[0084] The excavator 100 may be configured to automatically move the lower traveling structure 1 forward and backward. In this case, the hydraulic system portion related to the operation of the left traveling hydraulic motor 2ML and the hydraulic system portion related to the operation of the right traveling hydraulic motor 2MR may be configured in the same manner as the hydraulic system portion related to the operation of the boom cylinder 7, etc.

[0085] Although the description has been given of an electric control lever as a form of the operation device 26, a hydraulic operation lever may be adopted instead of the electric operation lever. In this case, the lever operation amount of the hydraulic operation lever may be detected in the form of pressure by a pressure sensor and input to the controller 30. Also, a solenoid valve may be disposed between the operation device 26 as a hydraulic operation lever and the pilot port of each control valve. The solenoid valve is configured to operate in response to an electric signal from the controller 30. With this configuration, when manual operation is performed using the operation device 26 as a hydraulic operation lever, the operation device 26 can move each control valve by increasing or decreasing the pilot pressure in response to the lever operation amount. Also, each control valve may be configured as an electromagnetic spool valve. In this case, the electromagnetic spool valve operates in response to an electric signal from the controller 30 corresponding to the lever operation amount of the electric operation lever.

[0086] Next, referring to FIG. 5, a configuration example of the controller 30 will be described. FIG. 5 is a diagram showing a configuration example of the controller 30. In FIG. 5, the controller 30 is configured to receive signals output from at least one of the operation device 26, the spatial recognition device 70, the operation method switching device SD, and the switch NS, execute various calculations, and output control commands to the proportional valve 31, etc. The controller 30 has a mode switching unit 30A, a bucket operation control unit 30B, and an arm operation control unit 30C as functional elements. Each functional element may be configured by hardware or software. The mode switching unit 30A, the bucket operation control unit 30B, and the arm operation control unit 30C are shown as being distinguished from each other for convenience of explanation, but they do not need to be physically distinguished from each other, and may be configured entirely or partially by a common software component or hardware component.

[0087] The mode switching unit 30A is configured to be able to switch the operation mode of the shovel 100. The operation modes of the shovel 100 include a vibration mode, a normal mode, and the like.

[0088] The normal mode is an operation mode used in excavation work, ground leveling work (leveling work), slope shaping work, etc. Specifically, the normal mode is an operation mode in which the actuator operates according to the operation direction and operation amount of the operation lever as described with reference to FIG. 3. More specifically, when the first operation method is selected, in the normal mode, the arm 5 is opened when the left operation lever 26L is tilted forward, the arm 5 is closed when the left operation lever 26L is tilted backward, the left rotation is performed when the left operation lever 26L is tilted left, and the right rotation is performed when the left operation lever 26L is tilted right. Also, when the first operation method is selected, in the normal mode, the boom 4 is lowered when the right operation lever 26R is tilted forward, the boom 4 is raised when the right operation lever 26R is tilted backward, the bucket 6 is closed when the right operation lever 26R is tilted left, and the bucket 6 is opened when the right operation lever 26R is tilted right.

[0089] The vibration mode is an operation mode used during gravel removal or gravel spreading work. Specifically, the vibration mode is an operation mode in which automatic vibration of the attachment is executed. The automatic vibration of the attachment includes at least the automatic vibration of the bucket 6. The automatic vibration of the attachment may be a combination of the automatic vibration of the bucket 6 and the automatic vibration of the arm 5. The combination of the automatic vibration of the bucket 6 and the automatic vibration of the arm 5 is also called "skeleton operation". The automatic vibration of the bucket 6 is also called "bucket skeleton operation", and the automatic vibration of the arm 5 is also called "arm skeleton operation". The automatic vibration of the bucket 6 is realized by repeated automatic opening and closing of the bucket 6. The repeated automatic opening and closing of the bucket 6 means that the slight opening operation of the bucket 6 and the slight closing operation of the bucket 6 are alternately and automatically repeated, regardless of the presence or absence of manual operation of the bucket operation lever. The opening angle of the bucket 6 due to the slight opening operation of the bucket 6 and the closing angle of the bucket 6 due to the slight closing operation of the bucket 6 may be the same or different. When the opening angle is larger than the closing angle, the bucket 6 opens gradually while repeatedly opening and closing. Conversely, when the opening angle is smaller than the closing angle, the bucket 6 closes gradually while repeatedly opening and closing.

[0090] In this embodiment, the mode switching unit 30A is configured to switch between a normal mode and a vibration mode each time a switch NS, which is a push button switch provided at the tip of the left operation lever 26L, is pressed. However, the mode switching unit 30A may be configured to cyclically switch between three or more operation modes each time the switch NS is pressed.

[0091] The bucket operation control unit 30B is configured to be able to control the operation of the bucket 6 in the vibration mode. In this embodiment, when the vibration mode is selected and the bucket operation lever is operated in the bucket opening direction, the bucket operation control unit 30B is configured to increase the opening angle in each automatic opening operation of the bucket 6, which constitutes the automatic opening and closing operation of the bucket 6, in accordance with the amount of operation. Furthermore, when the vibration mode is selected and the bucket operation lever is operated in the bucket closing direction, the bucket operation control unit 30B is configured to increase the closing angle in the automatic closing operation of the bucket 6, which constitutes the automatic opening and closing operation of the bucket 6, in accordance with the amount of operation. Note that even if the bucket operation lever is operated when the vibration mode is selected, only the opening and closing angle in the automatic opening and closing operation of the bucket 6 is adjusted, and the bucket 6 is not opened or closed as when the normal mode is selected.

[0092] The arm operation control unit 30C is configured to be able to control the operation of the arm 5 in the vibration mode. In this embodiment, the arm operation control unit 30C is configured to execute repeated automatic opening and closing operations of the arm 5 when the vibration mode is selected and the arm operation lever is not operated. The repeated automatic opening and closing operations of the arm 5 mean that, when the arm operation lever is not manually operated, a slight opening operation of the arm 5 and a slight closing operation of the arm 5 are alternately and automatically repeated. Note that the opening angle of the arm 5 due to the slight opening operation of the arm 5 and the closing angle of the arm 5 due to the slight closing operation of the arm 5 may be the same or different. When the opening angle is larger than the closing angle, the arm 5 gradually opens while repeatedly opening and closing. Conversely, when the opening angle is smaller than the closing angle, the arm 5 gradually closes while repeatedly opening and closing.

[0093] On the other hand, the arm operation control unit 30C is configured to stop the repeated automatic opening and closing operations of the arm 5 when the vibration mode is selected and the arm operating lever is operated.

[0094] Next, a process in which the controller 30 switches the operation mode of the shovel 100 (hereinafter referred to as "mode switching process") will be described with reference to Fig. 6. Fig. 6 is a flowchart showing an example of the flow of the mode switching process. The controller 30 repeatedly executes this mode switching process at a predetermined control period.

[0095] First, the mode switching unit 30A of the controller 30 determines whether or not the switch NS serving as a mode switching switch is pressed (step ST1). In this embodiment, the mode switching unit 30A determines whether or not the switch NS is pressed based on the output of the switch NS.

[0096] When it is determined that the mode change switch is pressed (YES in step ST1), the mode change unit 30A turns on the vibration mode (step ST2). Specifically, when the operation mode of the shovel 100 is the normal mode, the mode change unit 30A changes the operation mode to the vibration mode. When the operation mode of the shovel 100 is already the vibration mode, the mode change unit 30A continues the vibration mode without changing the operation mode.

[0097] Switching from the normal mode to the vibration mode is achieved by changing the content of the control command to the proportional valve 31. Specifically, when the vibration mode is turned ON, i.e., when the vibration mode is selected, the controller 30 alternately outputs a close command to the proportional valve 31CL (see FIG. 4C) and an open command to the proportional valve 31CR (see FIG. 4C), regardless of the operation direction and operation amount of the bucket operation lever. As a result, the bucket 6 operates to alternately repeat an automatic closing operation and an automatic opening operation.

[0098] On the other hand, when it is determined that the mode switching switch is not pressed (NO in step ST1), the mode switching unit 30A turns off the vibration mode (step ST3). Specifically, when the operation mode of the shovel 100 is the vibration mode, the mode switching unit 30A switches the operation mode to the normal mode. When the operation mode of the shovel 100 is already the normal mode, the mode switching unit 30A continues the normal mode without switching the operation mode.

[0099] Switching from the vibration mode to the normal mode is achieved by changing the content of the control command to the proportional valve 31. Specifically, when the vibration mode is turned OFF, that is, when the normal mode is selected, the controller 30 does not output a control command to the proportional valve 31CL and the proportional valve 31CR (see FIG. 4C) unless the bucket operation lever is operated. On the other hand, when the bucket operation lever is operated in the bucket closing direction, the controller 30 outputs a close command corresponding to the amount of operation to the proportional valve 31CL, so that the closing operation of the bucket 6 is performed according to the amount of operation. Also, when the bucket operation lever is operated in the bucket opening direction, the controller 30 outputs an open command corresponding to the amount of operation to the proportional valve 31CR, so that the opening operation of the bucket 6 is performed according to the amount of operation.

[0100] Next, a process (hereinafter, referred to as "bucket adjustment process") in which the controller 30 adjusts the content of the automatic opening / closing operation of the bucket 6 during the vibration mode will be described with reference to Fig. 7. Fig. 7 is a flowchart showing an example of the flow of the bucket adjustment process. When the vibration mode is ON, the controller 30 repeatedly executes this bucket adjustment process at a predetermined control period. In other words, when the vibration mode is ON, the controller 30 repeatedly executes the mode switching process and the bucket adjustment process in parallel at a predetermined control period.

[0101] First, bucket operation control section 30B of controller 30 detects the state of the bucket operation lever (step ST11). In this embodiment, bucket operation control section 30B detects the operation direction and operation amount of the bucket operation lever based on the output of operation sensor 29.

[0102] Thereafter, the bucket operation control unit 30B adjusts the content of the automatic opening / closing operation of the bucket 6 (step ST12). In this embodiment, the bucket operation control unit 30B adjusts the content of the automatic opening / closing operation of the bucket 6 according to the operation direction and operation amount of the bucket operation lever. Adjusting the content of the automatic opening / closing operation of the bucket 6 means, for example, determining the magnitude of the control command outputted to each of the proportional valves 31CL and 31CR. For example, when the bucket operation lever is operated in the bucket opening direction, the bucket operation control unit 30B increases the opening angle in each automatic opening operation of the bucket 6. In this case, the opening angle is adjusted so that it becomes larger as the operation amount becomes larger. Similarly, when the bucket operation lever is operated in the bucket closing direction, the bucket operation control unit 30B increases the closing angle in each automatic closing operation of the bucket 6. In this case, the closing angle is adjusted so that it becomes larger as the operation amount becomes larger.

[0103] Thereafter, the bucket operation control section 30B outputs a control command to at least one of the proportional valve 31CL and the proportional valve 31CR (step ST13).

[0104] With this configuration, the operator of the excavator 100 can manually adjust the automatic opening / closing operation of the bucket 6 so that it is a closing priority operation, or so that it is an opening priority operation, or so that the closing angle and the opening angle are approximately the same. Note that the "closing priority operation" means an operation in which the bucket 6 gradually closes while repeating the automatic opening / closing operation, and the "opening priority operation" means an operation in which the bucket 6 gradually opens while repeating the automatic opening / closing operation.

[0105] Next, a process in which the controller 30 adjusts the content of the automatic opening / closing operation of the arm 5 during the vibration mode (hereinafter referred to as "arm adjustment process") will be described with reference to Fig. 8. Fig. 8 is a flowchart showing an example of the flow of the arm adjustment process. When the vibration mode is ON, the controller 30 repeatedly executes this arm adjustment process at a predetermined control period. That is, when the vibration mode is ON, the controller 30 repeatedly executes the mode switching process, the bucket adjustment process, and the arm adjustment process in parallel at a predetermined control period.

[0106] First, the arm operation control unit 30C of the controller 30 determines whether or not the arm operation lever is operated (step ST21). In this embodiment, the arm operation control unit 30C determines whether or not the arm operation lever is operated based on the output of the operation sensor 29.

[0107] When it is determined that the arm operation lever is being operated (YES in step ST21), the arm operation control unit 30C stops the automatic opening / closing operation of the arm 5 (step ST22). This step ST22 is executed, for example, when gravel spreading work is being performed. That is, this step ST22 is executed when the arm operation lever is being operated while the switch NS is pressed. As a result, the manual opening / closing operation of the arm 5 and the automatic opening / closing operation of the bucket 6 are executed.

[0108] The gravel spreading operation is an operation for spreading gravel and the like contained in the bucket 6 on the ground, and is realized by moving the bucket 6, which is performing the automatic opening and closing operation, in a direction away from the shovel 100. For example, the operator of the shovel 100 performs the gravel spreading operation by performing a combined operation that is a combination of a boom lowering operation and an arm opening operation after pressing the switch NS to start the automatic opening and closing operation of the bucket 6, i.e., during the vibration mode. The operator may perform the gravel spreading operation by performing an arm opening operation or a boom lowering operation alone during the vibration mode, or by performing another combined operation such as a combined operation of a boom raising operation and an arm closing operation. Hereinafter, the vibration mode when the gravel spreading operation is being performed is referred to as the "gravel spreading mode".

[0109] When it is determined that the arm operating lever has not been operated (NO in step ST21), the arm operation control section 30C determines whether or not an automatic opening / closing operation of the arm 5 is being executed (step ST23). In this embodiment, the arm operation control section 30C determines whether or not the vibration mode is ON, that is, whether or not an automatic opening / closing operation of the arm 5 is being executed, based on the output of the switch NS.

[0110] When it is determined that the automatic opening / closing operation of the arm 5 is not being performed (NO in step ST23), the arm operation control unit 30C performs the automatic opening / closing operation of the arm 5 (step ST24). This step ST24 is performed, for example, when gravel removal work is being performed. In other words, this step ST24 is performed when the arm operating lever is not operated while the switch NS is pressed. As a result, the automatic opening / closing operation of the arm 5 and the automatic opening / closing operation of the bucket 6 are performed.

[0111] The gravel removal operation is an operation for sifting out small sized objects such as pebbles from large sized objects such as rocks contained in the bucket 6, and is realized by performing the automatic opening and closing operation of the arm 5 and the automatic opening and closing operation of the bucket 6. For example, the operator of the excavator 100 performs the gravel removal operation by pressing the switch NS to start the automatic opening and closing operation of the arm 5 and the automatic opening and closing operation of the bucket 6. Hereinafter, the vibration mode when the gravel removal operation is being performed is referred to as the "gravel removal mode."

[0112] When it is determined that the automatic opening / closing operation of the arm 5 is being performed (YES in step ST23), the arm operation control unit 30C ends the current arm adjustment process as it is. This YES determination in step ST23 is made, for example, when gravel removal work is being performed. In this case, the automatic opening / closing operation of the arm 5 and the automatic opening / closing operation of the bucket 6 are continued. There is no need to execute the automatic opening / closing operation of the arm 5 again. The NO determination in step ST23 is made, for example, when the gravel spreading work is completed. Specifically, it is made when the operation of the arm operating lever that was operated during the gravel spreading work is stopped. In this case, in this embodiment, the automatic opening / closing operation of the arm 5 is resumed. However, when the gravel spreading work is completed, the automatic opening / closing operation of the arm 5 does not have to be resumed. In this case, the automatic opening / closing operation of the bucket 6 is stopped. However, the automatic opening / closing operation of the bucket 6 may be continued.

[0113] Next, the transition over time of the opening command and closing command for the bucket 6 and the bucket angle when the bucket adjustment process is executed will be described with reference to Fig. 9. Fig. 9 is a diagram showing the transition over time of the opening command and closing command for the bucket 6 and the bucket angle. Specifically, the transition represented by the solid line in Fig. 9(A) to Fig. 9(C) represents the transition over time of the opening command for the proportional valve 31CR, the transition represented by the dotted line represents the transition over time of the closing command for the proportional valve 31CL, and the transition represented by the dashed and dotted line represents the transition over time of the bucket angle.

[0114] Furthermore, Figure 9(A) shows the transition over time when the first duration DA1 during which one open command is output is equal to the second duration DA2 during which one close command is output, Figure 9(B) shows the transition over time when the first duration DB1 during which one open command is output is shorter than the second duration DB2 during which one close command is output, and Figure 9(B) shows the transition over time when the first duration DC1 during which one open command is output is longer than the second duration DC2 during which one close command is output.

[0115] The first duration DA1-DC1 is the duration during which a current corresponding to an open command is applied to the proportional valve 31CR, and corresponds to the duration during which the secondary pressure of the proportional valve 31CR is maintained at or above a predetermined pressure. Similarly, the second duration DA2-DC2 is the duration during which a current corresponding to a close command is applied to the proportional valve 31CL, and corresponds to the duration during which the secondary pressure of the proportional valve 31CL is maintained at or above a predetermined pressure.

[0116] Specifically, the ratio between the first duration DA1 and the second duration DA2 in FIG. 9(A) is 1:1, the ratio between the first duration DB1 and the second duration DB2 in FIG. 9(B) is 0.6:1, and the ratio between the first duration DC1 and the second duration DC2 in FIG. 9(C) is 1:0.6.

[0117] In this embodiment, as shown in FIG. 9(A), when the first duration DA1 and the second duration DA2 are equal, the bucket angle returns to the original angle each time one opening operation and one closing operation are completed. On the other hand, as shown in FIG. 9(B), when the first duration DB1 is shorter than the second duration DB2, the bucket angle gradually decreases while the automatic opening / closing operation is repeated. That is, the bucket 6 gradually closes due to the closing priority operation. Also, as shown in FIG. 9(C), when the first duration DC1 is longer than the second duration DC2, the bucket angle gradually increases while the automatic opening / closing operation is repeated. That is, the bucket 6 gradually opens due to the opening priority operation.

[0118] In this way, the operator of the shovel 100 can manually adjust the movement of the bucket 6 during the automatic opening and closing operation by operating the bucket operating lever during the vibration mode so that the automatic opening and closing operation of the bucket 6 becomes a closing priority operation or an opening priority operation.

[0119] Specifically, the more the operator of the shovel 100 operates the bucket 6, the higher the priority can be. That is, the greater the amount of operation of the bucket operation lever in a desired direction, the higher the priority of the desired operation can be. More specifically, the greater the operator operates the bucket 6, the longer the command value in the priority direction (the movable direction of the bucket 6 corresponding to the bucket operation) can be than the command value in the other direction (the command value corresponding to the opposite direction to the priority direction). That is, the greater the amount of operation of the bucket operation lever in the opening direction, the longer the first duration during which one opening command is output and the shorter the second duration during which one closing command is output. Alternatively, the greater the amount of operation of the bucket operation lever in the closing direction, the shorter the first duration and the longer the second duration. As a result, the greater the operation of the bucket 6, the faster the opening / closing speed in the priority direction (the movable direction of the bucket corresponding to the bucket operation). That is, the greater the amount of operation of the bucket operation lever in the opening direction, the faster the bucket opening speed, and the greater the amount of operation of the bucket operation lever in the closing direction, the faster the bucket closing speed.

[0120] 9, the bucket adjustment process is realized by adjusting the duration of each of the open command and the close command. However, the bucket adjustment process may be realized by changing parameters other than the duration, such as the amplitude of the current command (open command and close command).

[0121] As described above, the excavator 100 according to the embodiment of the present invention includes the lower traveling body 1, the upper rotating body 3 rotatably mounted on the lower traveling body 1, the attachment AT including the arm 5 and the bucket 6 attached to the upper rotating body 3, and the operating device 26 for operating the attachment AT. The excavator 100 is configured to operate in a vibration mode including a gravel spreading mode. Furthermore, the excavator 100 may be configured to operate in a gravel removal mode.

[0122] The vibration mode is an operation mode used during gravel removal or gravel spreading operations. Specifically, the vibration mode is an operation mode in which automatic vibration of the attachment is executed. The automatic vibration of the attachment includes at least automatic vibration of the bucket 6. The automatic vibration of the attachment may be a combination of automatic vibration of the bucket 6 and automatic vibration of the arm 5. The automatic vibration of the bucket 6 is realized by repeated automatic opening and closing of the bucket 6. The repeated automatic opening and closing of the bucket 6 means that slight opening and closing of the bucket 6 are alternately and automatically repeated regardless of the presence or absence of manual operation of the bucket operation lever. Note that the opening angle of the bucket 6 due to the slight opening operation of the bucket 6 and the closing angle of the bucket 6 due to the slight closing operation of the bucket 6 may be the same or different. When the opening angle is larger than the closing angle, the bucket 6 gradually opens while repeatedly opening and closing. Conversely, when the opening angle is smaller than the closing angle, the bucket 6 gradually closes while repeatedly opening and closing.

[0123] The gravel spreading mode is a vibration mode when gravel spreading work is being performed. The gravel spreading work is a work for spreading gravel and the like contained in the bucket 6 on the ground, and is realized by moving the bucket 6 performing the automatic opening and closing operation in a direction away from the shovel 100. For example, the operator of the shovel 100 performs the gravel spreading work by performing a combined operation that is a combination of a boom lowering operation and an arm opening operation after pressing the switch NS to start the automatic opening and closing operation of the bucket 6, that is, during the vibration mode. The operator may perform the gravel spreading work by performing an arm opening operation or a boom lowering operation alone during the vibration mode, or by performing another combined operation such as a combined operation of a boom raising operation and an arm closing operation. The gravel spreading mode may also be defined as a mode that allows the operator to perform operations other than the bucket 6 during the automatic opening and closing operation of the bucket 6. Specifically, the gravel spreading mode may also be defined as a mode that allows the operator to operate the arm 5 or the boom 4 during the automatic opening and closing operation of the bucket. Alternatively, the gravel spreading mode may be defined as a mode in which at least one of the operation of the arm 5 and the boom 4 by the operator is possible during the automatic opening and closing operation of the bucket 6. Alternatively, the gravel spreading mode may be defined as a mode in which the automatic opening and closing operation of the bucket 6 and the operation of the arm 5 or the boom 4 in response to the operation by the operator are compatible.

[0124] The gravel removal mode is a vibration mode when gravel removal work is being performed. The gravel removal work is a work for sifting out small objects such as pebbles from large objects such as rocks contained in the bucket 6, and is realized by performing the automatic opening and closing operation of the arm 5 and the automatic opening and closing operation of the bucket 6. For example, the operator of the excavator 100 performs the gravel removal work by pressing the switch NS to start the automatic opening and closing operation of the arm 5 and the automatic opening and closing operation of the bucket 6. Note that the gravel removal work may be realized by performing either the automatic opening and closing operation of the arm 5 or the automatic opening and closing operation of the bucket 6.

[0125] With this configuration, the shovel 100 can automatically vibrate the bucket 6 with a simpler configuration than before.

[0126] The operating device 26 may include an arm operating lever for operating the arm 5. In the gravel spreading mode, the arm 5 may be configured to move in response to manual operation of the arm operating lever by an operator.

[0127] The shovel 100 may also have a switch NS that functions as a mode changeover switch for changing over between a normal mode and a vibration mode. In this configuration, the operator of the shovel 100 can start the automatic opening and closing operation of the bucket 6 simply by pressing the switch NS provided at the tip of the left operation lever 26L. Therefore, the operator can vibrate the arm 5 and the bucket 6 without performing a complicated operation, for example, by switching the first operation mode to the second operation mode by the operation mode switching device SD, and then tilting the left operation lever 26L alternately to the left and right and tilting the right operation lever 26R alternately to the left and right. Therefore, the shovel 100 can reduce the operator's fatigue associated with lever operation during gravel removal work, and can improve the work quality of the gravel removal work. Furthermore, the operator can vibrate the bucket 6 without performing a complicated operation, for example, by switching the first operation mode to the second operation mode by the operation mode switching device SD, and then tilting the right operation lever 26R alternately to the left and right. Therefore, the shovel 100 can reduce the fatigue of the operator associated with lever operation during gravel spreading work, and can improve the work quality of the gravel spreading work.

[0128] Additionally, the shovel 100 may be configured to operate in a gravel spreading mode when the arm 5 is operated in the vibration mode.

[0129] Furthermore, the shovel 100 may be configured so that, in the vibration mode, the automatic opening and closing operation of the bucket 6 is repeated. The content of the automatic opening and closing operation of the bucket 6 may be configured so as to be adjustable.

[0130] Furthermore, the operation device 26 may include a bucket operation lever for operating the bucket 6. The automatic opening and closing operation of the bucket 6 may be adjusted by the bucket operation lever. The operation device 26 is typically an electric operation lever.

[0131] The preferred embodiments of the present invention have been described above in detail. However, the present invention is not limited to the above-described embodiments. Various modifications or substitutions may be applied to the above-described embodiments without departing from the scope of the present invention. Furthermore, features described separately may be combined unless technical contradictions arise.

[0132] For example, in the example shown in Fig. 9, the total time TD of the first duration during which one open command is output and the second duration during which one close command is output is constant regardless of the magnitude relationship between the first duration and the second duration. However, this total time TD may be configured to be changeable on a setting screen or the like. In other words, the amplitude of the bucket angle during the automatic opening / closing operation of the bucket 6 may be configured to be changeable.

[0133] In the above embodiment, the controller 30 is configured to execute automatic vibration of the attachment when the switch NS is pressed. However, the controller 30 may be configured not to start automatic vibration of the attachment when the bucket 6 is present within a predetermined spatial area even when the switch NS is pressed. For example, the controller 30 may be configured not to start automatic vibration of the attachment when the height of the bucket 6 relative to the ground is equal to or greater than a preset upper limit, or when the height of the bucket 6 relative to the ground is equal to or less than a preset lower limit. The controller may be configured not to start automatic vibration of the attachment when the distance between the cabin 10 and the crawler 1C is less than a preset distance, or when the distance between the cabin 10 and the bucket 6 is less than a preset distance. This is to prevent stones or the like that have fallen from the bucket 6 from hitting the crawler 1C or the cabin 10. The height of the ground and the height of the bucket 6 relative to the ground may be calculated based on the output of the spatial recognition device 70, for example.

[0134] Alternatively, the controller 30 may automatically move the attachment so that the height of the bucket 6 with respect to the ground is a predetermined height. For example, when gravel spreading work is performed to spread gravel on the bottom of a ditch formed in front of the shovel 100, at least one of the up and down movement of the boom 4 and the opening and closing of the arm 5 may be automatically performed so that the distance between the bottom of the ditch and the bucket 6 is a preset distance. This is to ensure that gravel is spread from an appropriate height. In this case, the height of the ground, such as the bottom of the ditch, may also be calculated based on the output of the spatial recognition device 70. [Explanation of symbols]

[0135] 1···Lower traveling structure 1C···Crawler 1CL···Left crawler 1CR···Right crawler 2···Slewing mechanism 2A···Slewing hydraulic motor 2M···Travel hydraulic motor 2ML···Left traveling hydraulic motor 2MR···Right traveling hydraulic motor 3···Upper rotating structure 4···Boom 5···Arm 6···Bucket 7···Boom cylinder 8···Arm cylinder 9···Bucket cylinder 10···Cabin 11··Engine 13···Regulator 14···Main pump 15··Pilot pump 17···Control valve unit 18···Throttle 19···Control pressure sensor 26···Operating device 26D···Travel lever 26DL···Left travel lever 26DR···Right travel lever 26L···Left operating lever 26R Right operation lever 28 Discharge pressure sensor 29, 29DL, 29DR, 29LA, 29LB, 29RA, 29RB Operation sensor 29A Operation sensor 30 Controller 30A Mode switching unit 30B Bucket operation control unit 30C Arm operation control unit 31, 31AL~31DL, 31AR~31DR Proportional valve 40 Center bypass pipe 42 Parallel pipe 70 Spatial recognition device 70F Front sensor 70B Rear sensor 70L Left sensor 70R Right sensor 100 Excavator 171~176 Control valve AT Attachment NS Switch SD Operation method switching device

Claims

1. A lower running body; An upper rotating body rotatably mounted on the lower traveling body; An attachment including a boom, an arm, and a bucket attached to the upper rotating body; An operating lever for operating the attachment; A switch provided at the tip of the operating lever, the operation lever includes an arm operation lever for operating the arm, and is configured so that an operator can operate the arm while pressing the switch; The shovel is configured to operate in a vibration mode including a gravel spreading mode and a gravel removal mode when the switch is pressed; The shovel in question is, In the gravel spreading mode, when an operator operates the control lever while pressing the switch, the arm or the boom is operated in accordance with the amount of operation of the control lever while automatically opening and closing the bucket, and when the operator operates the control lever without pressing the switch, the arm or the boom is operated in accordance with the amount of operation of the control lever without automatically opening or closing the bucket, In the gravel removal mode, when an operator is not operating the arm operation lever while pressing the switch, the bucket is automatically opened and closed, and the arm is automatically opened and closed, and when an operator is operating the arm operation lever while pressing the switch, the bucket is automatically opened and closed while the arm is operated according to the amount of operation of the arm operation lever. Shovel.

2. The shovel is configured so that an operator can switch between the gravel spreading mode and the gravel removal mode without releasing the operating lever. The shovel according to claim 1.

3. In the gravel spreading mode, the arm moves in response to an operator's manual operation of the arm operating lever. The shovel according to claim 1 or 2.

4. The switch is a mode change switch that switches between a normal mode and the vibration mode. A shovel according to any one of claims 1 to 3.

5. When the arm is operated in the vibration mode, the arm is configured to operate in the gravel spreading mode. A shovel according to any one of claims 1 to 4.

6. In the vibration mode, the automatic opening and closing operation of the bucket is repeated, The contents of the automatic opening and closing operation of the bucket are configured to be adjustable. A shovel according to any one of claims 1 to 5.

7. the operation lever includes a bucket operation lever for operating the bucket, The automatic opening and closing operation of the bucket is adjusted by the bucket operation lever. The shovel according to claim 6.

8. The operating lever is an electric operating lever. A shovel according to any one of claims 1 to 7.

Images