WO2019116486A1

WO2019116486A1 - Excavator

Info

Publication number: WO2019116486A1
Application number: PCT/JP2017/044847
Authority: WO
Inventors: 春男呉
Original assignee: 住友重機械工業株式会社
Priority date: 2017-12-14
Filing date: 2017-12-14
Publication date: 2019-06-20
Also published as: CN111465737A; JPWO2019116486A1

Abstract

An excavator according to an embodiment of the present invention comprises a lower traveling body (1), an upper turning body (3) that is mounted on the lower traveling body (1), a cabin (10) that is mounted on the upper turning body (3), an operation lever that is disposed in the cabin (10) and that can simultaneously operate a plurality of actuators, and a controller (30) that adjusts the sensitivity of the operation lever. The controller (30), for example, adjusts the operation lever sensitivity by adjusting the size of the operation lever dead zone.

Description

Shovel

The present disclosure relates to a shovel including an operation lever configured to simultaneously operate a plurality of actuators.

DESCRIPTION OF RELATED ART The shovel comprised so that a boom cylinder, an arm cylinder, a bucket cylinder, and a turning motor could be moved with two control levers is known (refer patent document 1).

JP 2003-56011 A

When performing grooving work etc. with a shovel as described in patent document 1, the operator of a shovel may perform combined operation of boom lowering operation, arm closing operation, and bucket closing operation.

However, for example, in the configuration in which the swing motor is moved by moving the arm cylinder by operating one operation lever in the front-back direction and operating the arm cylinder in the left-right direction, the operator erroneously moves the swing motor when moving the arm cylinder. There is a risk of This is because even if the operating lever is operated accurately in the front-rear direction, the operating lever may be operated slightly diagonally.

In view of the above, it is desirable to provide a shovel that suppresses erroneous operations with an operation lever configured to simultaneously operate a plurality of actuators.

The shovel according to the embodiment of the present invention includes a lower traveling body, an upper revolving superstructure mounted on the lower traveling body, a driver's cab attached to the upper revolving superstructure, and a plurality installed in the operator's cab And a control device for adjusting the sensitivity of the operating lever.

By the above-mentioned means, it is possible to provide a shovel that suppresses erroneous operation with the operation lever configured to simultaneously operate a plurality of actuators.

It is a side view of a shovel concerning an example of the present invention. It is a block diagram which shows the structural example of the drive system of the shovel of FIG. It is the schematic which shows the structural example of the hydraulic system mounted in the shovel of FIG. It is a flowchart which shows the flow of sensitivity adjustment processing. It is a figure which shows the relationship between the lever operation amount of an arm control lever, and pilot pressure. It is a figure which shows the relationship between the lever operation amount of an arm control lever, and pilot pressure. It is the figure which looked at the control lever from just above. It is a flowchart of use promotion processing. It is a figure which shows the structural example of the operation system containing an electrical control apparatus. It is a figure which shows another structural example of the operation system containing an electrical control apparatus.

First, with reference to FIG. 1, a shovel (excavator) as a construction machine according to an embodiment of the present invention will be described. FIG. 1 is a side view of a shovel. An upper swing body 3 is mounted on a lower traveling body 1 of the shovel shown in FIG. 1 via a turning mechanism 2. A boom 4 as a working element is attached to the upper swing body 3. An arm 5 as a working element is attached to the tip of the boom 4, and a bucket 6 as a working element and an end attachment is attached to the tip of the arm 5. The boom 4, the arm 5 and the bucket 6 constitute a digging attachment as an attachment. The boom 4, the arm 5 and the bucket 6 are hydraulically driven by the boom cylinder 7, the arm cylinder 8 and the bucket cylinder 9 respectively. The upper revolving superstructure 3 is provided with a cabin 10 as a driver's cab, and a power source such as an engine 11 is mounted.

FIG. 2 is a block diagram showing a configuration example of a drive system of the shovel shown in FIG. 1, and the mechanical power transmission line, the hydraulic oil line, the pilot line and the electric control line are shown by double lines, thick solid lines, broken lines and dotted lines, respectively. Show.

The drive system of the shovel mainly includes the engine 11, the regulator 13, the main pump 14, the pilot pump 15, the control valve 17, the operating device 26, the pressure reducing valve 27, the discharge pressure sensor 28, the pressure sensor 29, the controller 30, the switch 31, etc. including.

The engine 11 is a driving source of a shovel. In the present embodiment, the engine 11 is, for example, a diesel engine as an internal combustion engine that operates to maintain a predetermined rotational speed. The output shaft of the engine 11 is connected to the input shaft of the main pump 14 and the pilot pump 15.

The main pump 14 is a device for supplying hydraulic fluid to the control valve 17 via a hydraulic fluid line, and is, for example, a swash plate type variable displacement hydraulic pump.

The regulator 13 is a device for controlling the discharge amount of the main pump 14. In the present 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 according to, for example, the discharge pressure of the main pump 14, the command current from the controller 30, and the like. Do.

The pilot pump 15 is a device that supplies hydraulic fluid to various hydraulic control devices including the operating device 26 via a pilot line, and is, for example, a fixed displacement hydraulic pump.

The control valve 17 is a hydraulic control device that controls a hydraulic system mounted on a shovel. Specifically, the control valve 17 includes a plurality of control valves that control the flow of the hydraulic fluid discharged by the main pump 14. The control valve 17 selectively supplies the hydraulic fluid discharged by the main pump 14 to one or more hydraulic actuators through the control valves. The control valves control the flow rate of hydraulic fluid flowing from the main pump 14 to the hydraulic actuator and the flow rate of hydraulic fluid flowing from the hydraulic actuator to the hydraulic fluid tank. The hydraulic actuator includes a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a left traveling hydraulic motor 1L, a right traveling hydraulic motor 1R, and a turning hydraulic motor 2A. The turning hydraulic motor 2A is an example of a turning device for turning the upper swing body 3 with respect to the lower traveling body 1 and may be replaced by a turning electric motor as an electric actuator.

The operating device 26 is a device used by the operator for operating the actuator. The actuator includes a hydraulic actuator and an electric actuator. In the present embodiment, the operating device 26 supplies the hydraulic fluid discharged by the pilot pump 15 to the pilot port of the control valve corresponding to each of the hydraulic actuators via the pilot line and the pressure reducing valve 27. The pressure of the hydraulic fluid supplied to each of the pilot ports (hereinafter referred to as "pilot pressure") is a pressure corresponding to the operating direction and operating amount of the lever or pedal of the operating device 26 corresponding to each of the hydraulic actuators. is there.

The pressure reducing valve 27 is a device that reduces the pilot pressure generated by the operating device 26 and outputs it. In the present embodiment, the pressure reducing valve 27 increases or decreases the pilot pressure according to the command current from the controller 30. For example, the pressure reducing valve 27 reduces the pilot pressure as the command current increases.

The discharge pressure sensor 28 is a sensor for detecting the discharge pressure of the main pump 14, and outputs the detected value to the controller 30.

The pressure sensor 29 is a sensor for detecting the operation content of the operator using the operating device 26. In the present embodiment, the pressure sensor 29 detects, for example, the operating direction and operating amount of the lever or pedal of the operating device 26 corresponding to each of the hydraulic actuators in the form of pressure, and outputs the detected values to the controller 30 Do. The operation content of the operating device 26 may be detected using another sensor other than the pressure sensor.

The controller 30 is a control device for controlling a shovel. In the present embodiment, the controller 30 is configured by, for example, a computer provided with a CPU, a RAM, an NVRAM, a ROM, and the like. Further, the controller 30 reads a program corresponding to the sensitivity adjustment unit 300 from the ROM and loads the program into the RAM, and causes the CPU to execute a corresponding process.

Specifically, the controller 30 executes the processing by the sensitivity adjustment unit 300 based on the output of the pressure sensor 29, the switch 31, and the like. Then, the controller 30 outputs a command according to the processing result of the sensitivity adjustment unit 300 to the pressure reducing valve 27 or the like.

The sensitivity adjustment unit 300 is a functional element that adjusts the sensitivity of the operation lever as the operation device 26. In the present embodiment, the left control lever of the two control levers installed in the cabin 10 functions as an arm control lever and a turning control lever, and the right control lever functions as a boom control lever and a bucket control lever. Specifically, the operation in the front-rear direction of the left operation lever corresponds to the operation of the arm operation lever, and the operation in the left-right direction of the left operation lever corresponds to the operation of the turn operation lever. More specifically, the forward operation of the left operation lever corresponds to the arm opening operation, and the backward operation opposite to the front direction corresponds to the arm closing operation. Further, the operation of the left operation lever in the left direction corresponds to the left turn operation, and the operation in the right direction opposite to the left direction corresponds to the right turn operation. Further, the operation of the right operating lever in the front-rear direction corresponds to the operation of the boom operating lever, and the operation of the right operating lever in the left-right direction corresponds to the operation of the bucket operating lever. More specifically, the operation in the forward direction of the right control lever corresponds to the boom lowering operation, and the operation in the backward direction opposite to the front direction corresponds to the boom raising operation. Further, the operation of the right control lever in the left direction corresponds to the bucket closing operation, and the operation in the right direction opposite to the left direction corresponds to the bucket opening operation. The operator can operate the arm 5 and the turning device at the same time using the left operation lever, and can operate the boom 4 and the bucket 6 simultaneously using the right operation lever. The longitudinal direction and the lateral direction of the operating lever are substantially orthogonal to each other.

The sensitivity adjustment unit 300 can maintain, for example, the sensitivity of the arm operation lever and lower the sensitivity of the swing operation lever with respect to the left operation lever. In this case, the operator may move the turning device even when the driver intends to operate (tilt) the left operation lever in the front-rear direction but operates (tilt) slightly in a diagonal direction. Absent. By lowering the sensitivity of the turning operation lever, it is difficult to reflect the operation on the turning operation lever.

The switch 31 is a functional element that switches the operation mode of the shovel. In the present embodiment, the switch 31 is a software switch displayed on the screen of a display device such as a car-mounted display with a touch panel. The switch 31 may be a hardware switch installed in the cabin 10.

The operation mode of the shovel includes an operation error prevention mode. The erroneous operation preventing mode is an operation mode for suppressing or preventing the erroneous operation of the operating lever. When the erroneous operation prevention mode is selected, the shovel starts adjustment of the sensitivity of the operation lever by the sensitivity adjustment unit 300 as needed. With this configuration, the operator can switch between activation and deactivation of the function of adjusting the sensitivity of the operation lever.

Next, with reference to FIG. 3, the details of the hydraulic system mounted on the shovel will be described. FIG. 3 is a schematic view showing a configuration example of a hydraulic system mounted on the shovel of FIG. Similar to FIG. 2, FIG. 3 shows the mechanical power transmission line, the hydraulic fluid line, the pilot line, and the electrical control line, respectively, by a double line, a thick solid line, a broken line, and a dotted line.

In FIG. 3, the hydraulic system circulates the hydraulic oil from the

main pumps

14L, 14R driven by the engine 11 to the hydraulic oil tank through the center bypass pipelines 40L, 40R and the

parallel pipelines

42L, 42R. The

main pumps

14L, 14R correspond to the main pump 14 of FIG.

The center bypass line 40L is a hydraulic oil line passing through control valves 171L to 175L disposed in the control valve 17. The center bypass line 40R is a hydraulic oil line passing through control valves 171R to 175R disposed in the control valve 17.

The control valve 171L supplies the hydraulic fluid discharged by the main pump 14L to the left traveling hydraulic motor 1L, and the flow of the hydraulic oil for discharging the hydraulic fluid discharged by the left traveling hydraulic motor 1L to the hydraulic oil tank It is a spool valve which switches.

The control valve 171R is a spool valve as a straight traveling valve. The control valve 171R switches the flow of hydraulic fluid so that the hydraulic fluid is supplied from the main pump 14L to the left side traveling hydraulic motor 1L and the right side traveling hydraulic motor 1R in order to improve the rectilinearity of the lower traveling body 1. Specifically, when the left side traveling hydraulic motor 1L and the right side traveling hydraulic motor 1R and any other hydraulic actuators are operated at the same time, the main pump 14L is the left side traveling hydraulic motor 1L and the right side traveling hydraulic Hydraulic oil is supplied to both of the motor 1R. When none of the other hydraulic actuators are operated, the main pump 14L supplies hydraulic fluid to the left traveling hydraulic motor 1L, and the main pump 14R supplies hydraulic fluid to the right traveling hydraulic motor 1R.

The control valve 172L supplies hydraulic fluid discharged by the main pump 14L to the optional hydraulic actuator, and a spool valve that switches the flow of hydraulic fluid to discharge hydraulic fluid discharged by the optional hydraulic actuator to the hydraulic fluid tank. It is. The option hydraulic actuator 50 is, for example, a grapple open / close cylinder.

The control valve 172R supplies the hydraulic fluid discharged by the main pump 14R to the right-side traveling hydraulic motor 1R, and the flow of the hydraulic oil for discharging the hydraulic fluid discharged by the right-side traveling hydraulic motor 1R to the hydraulic oil tank. It is a spool valve which switches.

The control valve 173L supplies the hydraulic fluid discharged by the main pump 14L to the swing hydraulic motor 2A, and switches the flow of the hydraulic fluid to discharge the hydraulic fluid discharged by the swing hydraulic motor 2A to the hydraulic fluid tank. It is a spool valve.

The control valve 173R is a spool valve for supplying the hydraulic fluid discharged by the main pump 14R to the bucket cylinder 9 and discharging the hydraulic fluid in the bucket cylinder 9 to a hydraulic fluid tank.

The control valves 174L and 174R supply hydraulic fluid discharged by the

main pumps

14L and 14R to the boom cylinder 7, and switch the flow of hydraulic fluid to discharge the hydraulic fluid in the boom cylinder 7 to the hydraulic fluid tank. It is a valve. In the present embodiment, the control valve 174L operates only when the raising operation of the boom 4 is performed, and does not operate when the lowering operation of the boom 4 is performed.

The

control valves

175L and 175R supply hydraulic fluid discharged by the

main pumps

14L and 14R to the arm cylinder 8, and switch the flow of hydraulic fluid to discharge the hydraulic fluid in the arm cylinder 8 to the hydraulic fluid tank. It is a valve.

The parallel line 42L is a hydraulic oil line parallel to the center bypass line 40L. The parallel pipeline 42L can supply hydraulic fluid to the control valve further downstream if the flow of hydraulic fluid through the center bypass pipeline 40L is restricted or shut off by any of the control valves 171L to 174L. The parallel line 42R is a hydraulic oil line parallel to the center bypass line 40R. The parallel line 42R can supply hydraulic fluid to the control valve further downstream if the flow of hydraulic fluid through the center bypass line 40R is restricted or shut off by any of the control valves 172R to 174R.

The

regulators

13L, 13R control the discharge amounts of the

main pumps

14L, 14R by adjusting the swash plate tilt angles of the

main pumps

14L, 14R according to the discharge pressures of the

main pumps

14L, 14R. The

regulators

13L and 13R correspond to the regulator 13 of FIG. The

regulators

13L, 13R, for example, adjust the swash plate tilt angles of the

main pumps

14L, 14R to decrease the discharge amount when the discharge pressures of the

main pumps

14L, 14R become equal to or greater than a predetermined value. This is to prevent the absorption horsepower of the main pump 14 represented by the product of the discharge pressure and the discharge amount from exceeding the output horsepower of the engine 11.

The arm control lever 26 </ b> A is an example of the control device 26 and is used to operate the arm 5. Further, the arm control lever 26A applies the pilot pressure corresponding to the lever operation amount to the pilot ports of the

control valves

175L and 175R by using the hydraulic oil discharged by the pilot pump 15. Specifically, when the arm control lever 26A is operated in the arm closing direction, the pilot pressure is applied to the right pilot port of the control valve 175L and the pilot pressure is applied to the left pilot port of the control valve 175R. . The pilot pressure at this time is generated by the remote control valve 26AVL using the hydraulic oil discharged by the pilot pump 15. On the other hand, when the arm control lever 26A is operated in the arm opening direction, the pilot pressure is applied to the left pilot port of the control valve 175L and the pilot pressure is applied to the right pilot port of the control valve 175R. The pilot pressure at this time is generated by the remote control valve 26AVR using the hydraulic oil discharged by the pilot pump 15.

The pressure reducing valves 27AL and 27AR are solenoid valves that operate in response to a command from the controller 30, and correspond to the pressure reducing valve 27 in FIG. The pressure reducing valve 27AL reduces the pilot pressure generated by the remote control valve 26AVL when the arm operating lever 26A is operated in the closing direction and causes the pilot pressure on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R. The pressure reducing valve 27AR reduces the pilot pressure generated by the remote control valve 26AVR when the arm operating lever 26A is operated in the opening direction, and applies the pressure to the left pilot port of the control valve 175L and the right pilot port of the control valve 175R.

The pressure sensor 27A is a sensor for detecting the post-decompression pilot pressure after the decompression by the decompression valves 27AL and 27AR, and outputs the detected value to the controller 30.

The pressure sensor 29A corresponds to the pressure sensor 29 of FIG. The pressure sensor 29A detects the operation content of the operator on the arm control lever 26A in the form of pressure, and outputs the detected value to the controller 30. The operation content is, for example, a lever operation direction, a lever operation amount (lever operation angle), and the like.

The left and right travel levers (or pedals), the boom operation lever, the bucket operation lever, and the turning operation lever (all not shown) respectively travel the lower traveling body 1, move the boom 4 up and down, open and close the bucket 6, It is an operating device for operating turning of upper revolving unit 3. Similar to the arm control lever 26A, these control devices control the pilot pressure corresponding to the lever operation amount (or the pedal operation amount) corresponding to each of the hydraulic actuators using the hydraulic oil discharged by the pilot pump 15 Act on either the left or right pilot port of the valve. In addition, the operation content of the operator with respect to each of these operation devices is detected in the form of pressure by the corresponding pressure sensor as in the pressure sensor 29A, and the detected value is output to the controller 30.

Further, FIG. 3 shows only the arm control lever 26A and the pilot line thereof for the sake of clarity, but in practice the boom control lever, the bucket control lever, the turning control lever and the like also correspond via the pilot line. It is connected to the pilot port of the control valve.

Here, negative control control (hereinafter referred to as "negative control") employed in the hydraulic system of FIG. 3 will be described.

The center bypass lines 40L, 40R are provided with negative control throttles 18L, 18R between the hydraulic oil tanks and the

control valves

175L, 175R located most downstream. The flow of hydraulic fluid discharged by the

main pumps

14L, 14R is limited by the negative control throttles 18L, 18R. Then, the

negative control diaphragms

18L and 18R generate control pressure (hereinafter referred to as "negative control pressure") for controlling the

regulators

13L and 13R.

The negative

control pressure sensors

19L and 19R are sensors for detecting the negative control pressure generated upstream of the negative control stops 18L and 18R. In the present embodiment, the negative

control pressure sensors

19L and 19R output the detected values to the controller 30.

The controller 30 outputs a command corresponding to the negative control pressure to the

regulators

13L and 13R. The

regulators

13L, 13R control the discharge amounts of the

main pumps

14L, 14R by adjusting the swash plate tilt angles of the

main pumps

14L, 14R according to the command. Specifically, the

regulators

13L and 13R reduce the discharge amount of the

main pumps

14L and 14R as the negative control pressure is larger, and increase the discharge amounts of the

main pumps

14L and 14R as the negative control pressure is smaller.

When none of the hydraulic actuators are operated (hereinafter referred to as "standby mode"), the hydraulic fluid discharged by the

main pumps

14L, 14R passes through the center bypass pipelines 40L, 40R and the negative control throttles 18L, 18R. Lead to The flow of hydraulic fluid discharged by the

main pumps

14L, 14R increases the negative control pressure generated upstream of the negative control throttles 18L, 18R. As a result, the

regulators

13L and 13R reduce the discharge amount of the

main pumps

14L and 14R to the allowable minimum discharge amount, and the pressure loss (pumping loss) when the discharged hydraulic oil passes through the center bypass pipelines 40L and 40R. Suppress.

On the other hand, when any hydraulic actuator is operated, the hydraulic fluid discharged by the

main pumps

14L, 14R flows into the hydraulic actuator to be operated via the control valve corresponding to the hydraulic actuator to be operated. The control valve reduces or eliminates the amount of hydraulic oil reaching the negative control throttles 18L and 18R, and reduces the negative control pressure generated upstream of the negative control throttles 18L and 18R. As a result, the

regulators

13L and 13R increase the discharge amount of the

main pumps

14L and 14R, circulate sufficient hydraulic oil to the hydraulic actuator to be operated, and ensure the driving of the hydraulic actuator to be operated.

With the configuration as described above, the hydraulic system of FIG. 3 can suppress unnecessary energy consumption in the

main pumps

14L and 14R in the standby mode. The wasteful energy consumption includes the pumping loss generated by the hydraulic fluid discharged by the

main pumps

14L, 14R in the center bypass lines 40L, 40R.

Further, in the hydraulic system of FIG. 3, when operating the hydraulic actuators, it is possible to reliably supply necessary and sufficient hydraulic oil from the

main pumps

14L and 14R to the hydraulic actuator to be operated.

Next, with reference to FIG. 4, a process in which the controller 30 adjusts the sensitivity of the operation lever (hereinafter, referred to as “sensitivity adjustment process”) will be described. FIG. 4 is a flowchart showing the flow of sensitivity adjustment processing. In the example of FIG. 4, sensitivity adjustment processing of the arm operation lever 26A and the left operation lever that functions as a turning operation lever will be described. However, the following description is equally applied to the right control lever which functions as the boom control lever and the bucket control lever.

First, the sensitivity adjustment unit 300 of the controller 30 determines whether or not the erroneous operation preventing mode is set (step ST1). The erroneous operation prevention mode is selected, for example, by the operation input of the operator via the switch 31. The sensitivity adjustment unit 300 may automatically select the erroneous operation prevention mode when a predetermined condition is satisfied.

When it is determined that the operation error prevention mode is set (YES in step ST1), the sensitivity adjustment unit 300 compares the lever operation amount of the arm operation lever 26A with the lever operation amount of the turning operation lever, and operates the lever operation of the arm operation lever 26A. It is determined whether the amount is equal to or more than the amount obtained by adding the predetermined amount α to the lever operation amount of the turning operation lever (step ST2). The predetermined amount α is an amount preset in the controller 30 or the like, and for example, is used to determine whether the lever operation amount of the arm operation lever 26A is overwhelmingly larger than the lever operation amount of the turning operation lever Be For example, based on the output of the pressure sensor 29A, the sensitivity adjustment unit 300 acquires the lever operation amounts of the arm operation lever 26A and the turning operation lever as comparable values. For example, the lever operation amounts of the arm control lever 26A and the turning control lever are obtained in the form of comparable values such as pilot pressure and lever inclination angle.

When it is determined that the lever operation amount of the arm operation lever 26A is less than the amount obtained by adding the predetermined amount α to the lever operation amount of the turning operation lever (NO in step ST2), the sensitivity adjustment unit 300 detects the arm operation lever 26A. The amount of lever operation of the lever and the amount of lever operation of the turning operation lever are compared, and it is determined whether the amount of lever operation of the turning operation lever is equal to or greater than the predetermined amount α added to the amount of lever operation of the arm operation lever 26A. (Step ST3). Here, the predetermined amount α is an amount preset in the controller 30 or the like, and for example, it is determined whether the lever operation amount of the turning operation lever is overwhelmingly larger than the lever operation amount of the arm operation lever 26A. Used for The predetermined amount α in step ST3 may be different from the predetermined amount α in step ST2.

When it is determined that the lever operation amount of the turning operation lever is equal to or more than the amount obtained by adding the predetermined amount α to the lever operation amount of the arm operation lever 26A (YES in step ST3), the sensitivity adjustment unit 300 detects the arm operation lever 26A. Lower the sensitivity (step ST4). For example, the sensitivity adjustment unit 300 outputs a control command to each of the pressure reducing valve 27AL and the pressure reducing valve 27AR shown in FIG. 3 to reduce the pilot pressure generated by the arm control lever 26A.

By this processing, the arm 5 is opened even when the operator intends to operate the left operation lever in the right direction to turn right but operates in the slightly forward right direction. It can be suppressed or prevented. This is because the arm opening side pilot pressure that has been increased unintentionally can be reduced.

When it is determined that the lever operation amount of the turning operation lever is less than the amount obtained by adding the predetermined amount α to the lever operation amount of the arm operation lever 26A (NO in step ST3), the sensitivity adjustment unit 300 adjusts the sensitivity of the operation lever The normal control is executed without performing (step ST5). The difference between the lever operation amount of the turning operation lever and the lever operation amount of the arm operation lever 26A is less than a predetermined amount α, that is, the turning operation lever and the arm operation lever 26A are simultaneously operated with substantially the same lever operation amount, This is because it can be determined that it is not necessary to adjust the sensitivity of the lever. The normal control is a control based on the pilot pressure generated by the operating device 26 without sensitivity adjustment.

On the other hand, when it is determined that the lever operation amount of the arm operation lever is equal to or more than the amount obtained by adding the predetermined amount α to the lever operation amount of the turning operation lever (YES in step ST2), the sensitivity adjustment unit 300 detects the sensitivity of the turning operation lever. Lower (step ST6). For example, the sensitivity adjustment unit 300 outputs a control command to the pressure reducing valve as described above, and reduces the pilot pressure generated by the turning operation lever.

By this processing, even if the operator intends to operate the left operation lever to the rear (front side) to close the arm but operates it slightly diagonally to the left, the upper swing body 3 rotates left. It can control or prevent that it turns. This is because it is possible to reduce the left turn side pilot pressure which has been unintentionally increased.

Further, in the example of FIG. 4, the sensitivity adjustment unit 300 automatically reduces the sensitivity of the operation lever with the smaller lever operation amount. However, the present invention is not limited to this configuration. For example, the operator may set the sensitivity of the desired operating lever to be reduced to the desired level. For example, the operator may set the sensitivity so that only the sensitivity of the specific operation lever is reduced using the switch 31, and the degree of the reduction may be set in detail. For example, the operator may significantly reduce the sensitivity of the operating lever that he does not intend to move.

Next, referring to FIGS. 5A and 5B, a specific method of adjusting the sensitivity of the operating lever will be described. In both FIGS. 5A and 5B, the detected value of pressure sensor 29A (hereinafter referred to as "primary side pilot pressure") representing the lever operation amount of arm operation lever 26A and the detected value of pressure sensor 27A (hereinafter referred to as " It is a figure which shows the relationship between "the secondary side pilot pressure". The primary side pilot pressure is a pilot pressure on the upstream side (arm control lever 26A side) of the pressure reducing valves 27AL, 27AR, and the secondary side pilot pressure is downstream of the pressure reducing valves 27AL, 27AR (control

valves

175L, 175R side Pilot pressure). The lever operation amount can be calculated based on the primary side pilot pressure and the characteristics of the remote control valve 26AV. Although the primary side pilot pressure is actually represented by a positive value, in FIGS. 5A and 5B, for convenience, the primary side pilot pressure in the arm opening direction is represented by a positive value, and the primary side pilot in the arm closing direction is represented. Pressure is expressed as a negative value. The right side of the horizontal axis indicates the primary side pilot pressure (positive value) in the arm opening direction, and the left side of the horizontal axis indicates the primary side pilot pressure (negative value) in the arm closing direction. The vertical axis represents the secondary side pilot pressure acting on the pilot port. The solid line shows the relationship after sensitivity adjustment, and the broken line shows the relationship before sensitivity adjustment.

FIG. 5A shows a method of reducing the sensitivity of the arm control lever 26A by expanding the dead zone of the arm control lever 26A. Specifically, a method of shifting the secondary side pilot pressure with the pressure reducing valve based on the lever operation amount is shown. The dead zone means a range in which the lever operation amount is considered to be zero even if it is not zero. The sensitivity adjustment unit 300 outputs a command to the pressure reducing valve 27AL and the pressure reducing valve 27AR, and the dead zone in the range W1 of the primary side pilot pressure -L1 to + L1 is set to the range W2 of the primary side pilot pressure -L2 to + L2. Expanding. Therefore, if the primary side pilot pressure on the open side of the arm control lever 26A is 0 to + L2, the secondary side pilot pressure acting on the arm open side pilot port displaces the control valve 175L and the control valve 175R from the neutral position It is maintained at the level which does not Similarly, if the primary side pilot pressure on the closing side of the arm control lever 26A is -L2 to 0, the secondary side pilot pressure acting on the arm closing side pilot port moves the control valve 175L and the control valve 175R to the neutral position. Maintained at a level that does not displace from In the example of FIG. 5A, the dead zone is changed by the same width (L2-L1) on both the arm open side and the arm closed side, but the dead zone is changed by different widths on the arm open side and the arm closed side. It is also good.

FIG. 5B shows a method of lowering the sensitivity of the arm control lever 26A by reducing the rate of increase of the secondary side pilot pressure with respect to the primary side pilot pressure of the arm control lever 26A. Specifically, a method is shown in which the rate of increase (inclination) of the secondary side pilot pressure is changed by the pressure reducing valve based on the lever operation amount. The sensitivity adjustment unit 300 outputs a command to the pressure reducing valve 27AL and the pressure reducing valve 27AR, and increases the rate of increase of the secondary side pilot pressure to the primary side pilot pressure when operating the arm control lever 26A in the opening direction from θ1 to θ2. Reduce. Therefore, the secondary side pilot pressure which has started to increase when the primary side pilot pressure is + L1 and reaches the maximum value at + L2 is delayed to reach the maximum value when + L3 instead of + L2. The same applies when the arm control lever 26A is operated in the closing direction. In the example of FIG. 5B, although the increase rate is changed by the same slope (θ1-θ2) on both the arm open side and the arm close side, the increase rate is changed by different slopes on the arm open side and the arm close side. You may

As described above, the sensitivity adjustment unit 300 can adjust the sensitivity of the control lever by controlling the pressure reducing valve 27AL and the pressure reducing valve 27AR to change the relationship between the primary side pilot pressure and the secondary side pilot pressure. Therefore, when the operator tries to operate the left operating lever only in the turning direction, the arm 5 does not open even if the left operating lever is unintentionally tilted in the arm opening direction. As a result, it is possible to prevent an arm opening operation not intended by the operator. Moreover, although FIG. 5A and FIG. 5B demonstrated regarding arm control lever 26A, the same may be said of the other control lever.

Next, the erroneous operation rate will be described with reference to FIG. FIG. 6 is a view of the left operating lever as viewed from directly above. The vertical axis corresponds to the operating direction of the arm operating lever 26A, and the horizontal axis corresponds to the operating direction of the turning operating lever.

The shaded area in FIG. 6 indicates a dead zone. Specifically, a hatched region extending in the lateral direction indicates the dead zone of the arm control lever 26A, and a hatched region extending in the longitudinal direction indicates the dead zone of the turning operation lever. The dot pattern area in FIG. 6 indicates a fine operation area. Specifically, the dot pattern area extending in the lateral direction indicates the fine operation area of the arm control lever 26A, and the dot pattern area extending in the longitudinal direction indicates the fine operation area of the turning control lever.

The lever position P0 indicates that the left operation lever is in the neutral position, and the lever position P1 indicates that the turn operation lever is operated in the left turn direction as intended by the operator.

The lever position P2 indicates a state in which the turning operation lever is operated in the right turning direction and the arm operation lever 26A is operated in the closing direction as intended by the operator.

In the lever position P3, the turning operation lever is operated in the right turning direction as intended by the operator, but contrary to the operator's intention, the arm operating lever 26A is erroneously operated in the opening direction. Show.

The lever position P4 indicates that the arm control lever 26A is operated in the opening direction as intended by the operator, but the turning operation lever has been erroneously operated in the left turning direction against the operator's intention. .

In the above-mentioned example, the state shown by each of the lever position P3 and the lever position P4 indicates a state in which an erroneous operation is being performed. That is, in the above-described example, the erroneous operation is performed when the swing operation lever is finely operated when the arm operation lever 26A is operated beyond the fine operation area (a state indicated by the lever position P4 )including. Also, it includes a state in which the arm control lever 26A is finely operated (a state indicated by the lever position P3) when the turning operation lever is operated beyond the fine operation area.

In the normal control, the erroneous operation rate is calculated based on the statistical value of the time operated in the fine operation area shown in FIG. 6 (the time when the erroneous operation is performed) within a predetermined time. For example, it is derived as a ratio of the erroneous operation time to the total operation time of the left operation lever. The total operation time is, for example, the time when the control lever is at a position other than the neutral position or the time when the control lever is at a position other than the dead zone. The erroneous operation time is, for example, a time during which an erroneous operation is being performed. The erroneous operation rate may be derived as a ratio of the number of erroneous operations to the total number of operations of the operating lever, or may be derived in other manners. One operation of the operating lever is, for example, an operation from when the operating lever comes out of the neutral position and returns to the neutral position. The controller 30 can grasp not only the calculation of the erroneous operation rate but also the feature of the lever operation which the operator can easily operate erroneously. For example, the controller 30 can grasp for each operator a tendency that a certain operator unintentionally tilts the left operation lever in the right turning direction when attempting to close the arm only. In this case, the controller 30 may reduce only the sensitivity to the right turn operation. That is, no change from the normal control is necessary for the sensitivity to the left turn operation.

Next, with reference to FIG. 7, a process (hereinafter, referred to as “use promotion process”) in which the controller 30 prompts the operator to use the erroneous operation prevention mode will be described. FIG. 7 is a flowchart of the use promotion process. The controller 30 repeatedly executes the usage promotion process at a predetermined control cycle.

First, the controller 30 determines whether the misoperation rate is equal to or greater than a predetermined threshold (step ST11). For example, the controller 30 stores the operation content of the operation lever in time series. Then, an erroneous operation rate is derived based on the operation history at a predetermined time. The predetermined time is, for example, a predetermined time (for example, one hour) after the start of the engine. Then, it is determined whether the erroneous operation rate in a predetermined time is equal to or more than a threshold.

When it is determined that the misoperation rate is equal to or higher than the threshold (YES in step ST11), the controller 30 promotes the use of the misoperation prevention mode (step ST12). For example, the controller 30 displays a text message promoting the use of the erroneous operation prevention mode on the screen of the display device together with the switch 31 as a software switch. The operator can start the erroneous operation prevention mode by pressing the switch 31. A voice message may be output from the on-vehicle speaker that promotes the use of the erroneous operation prevention mode.

The controller 30 may automatically start the erroneous operation prevention mode. In this case, the controller 30 may display an image indicating that the operation error prevention mode is in progress on the screen of the display device, and periodically output a voice message indicating that the operation error prevention mode is in progress from the on-vehicle speaker It is also good. A voice message may be output from the in-vehicle speaker indicating that the operation error prevention mode has been started.

When the erroneous operation prevention mode is started, the sensitivity adjustment unit 300 may change the adjustment content of the sensitivity of the operation lever according to the erroneous operation rate. For example, the sensitivity adjustment unit 300 may increase the width of the dead zone as the erroneous operation rate is higher. Alternatively, the sensitivity adjustment unit 300 may reduce the increase rate of the pilot pressure with respect to the lever operation amount as the erroneous operation rate is higher.

When it is determined that the erroneous operation rate is less than the threshold (NO in step ST11), the controller 30 ends the current use promotion process without promoting the use of the erroneous operation prevention mode.

Thus, the controller 30 can derive an erroneous operation rate based on the operation history of the operation lever, and when the erroneous operation rate is equal to or higher than a predetermined threshold, can prompt the operator to use the erroneous operation prevention mode or prevent erroneous operation The mode can be started automatically.

Further, the controller 30 can change the adjustment content of the sensitivity of the operation lever according to the erroneous operation rate. Therefore, appropriate sensitivity adjustment can be performed according to the frequency of erroneous operation. Furthermore, the feature of the operation can be grasped for each operator, and in accordance with the feature, the lever operation direction to which the sensitivity is to be changed and the sensitivity adjustment amount can be determined.

With the above configuration, the controller 30 can suppress or prevent the turning operation from being accidentally entered during the arm operation in the sequence work such as the trench digging work in a narrow space. Therefore, it can control or prevent that a shovel accidentally contacts surrounding local features. As a result, the safety, operability and work efficiency of the shovel can be improved.

The preferred embodiments of the present invention have been described above in detail. However, the present invention is not limited to the embodiments described above. Various modifications, substitutions, and the like may be applied to the embodiment described above without departing from the scope of the present invention. Also, the features described separately can be combined as long as no technical contradiction arises.

For example, in the above-described embodiment, the sensitivity adjustment unit 300 automatically reduces the sensitivity of the control lever with the smaller lever operation amount. However, the present invention is not limited to this configuration. For example, the sensitivity adjustment unit 300 determines whether or not an erroneous operation is being performed using the fine operation area as shown in FIG. 6, and determines that the erroneous operation is being performed, The sensitivity of the control lever with the smaller lever operation amount may be automatically reduced. That is, even in the erroneous operation prevention mode, when it is determined that no erroneous operation is performed, the sensitivity of the operation lever with the smaller lever operation amount may be maintained without being reduced.

Moreover, in the above-mentioned Example, although the hydraulic control apparatus is employ | adopted as the control device 26, an electrical control apparatus may be employ | adopted. FIG. 8 shows a configuration example of an operation system including an electric operation device. Specifically, the operation system of FIG. 8 is an example of a boom operation system, and mainly includes a pilot pressure control valve 17, a boom operation lever 26B as an electric operation lever, a controller 30, and a boom It is comprised by the solenoid valve 60 for raising operation, and the solenoid valve 62 for boom lowering operation. The operation system of FIG. 8 may be applied to an arm operation system, a bucket operation system, and the like as well.

The pilot pressure operated control valve 17 includes control valves 174L and 174R for the boom cylinder 7, as shown in FIG. The solenoid valve 60 is configured to be able to adjust the flow passage area of the oil passage connecting the pilot pump 15 with the right (raised) pilot port of the control valve 174L and the left (raised) pilot port of the control valve 174R. ing. The solenoid valve 62 is configured to adjust the flow passage area of the oil passage connecting the pilot pump 15 and the right (lower) pilot port of the control valve 174R.

When the manual operation is performed, the controller 30 receives the boom raising operation signal (electric signal) or the boom lowering operation signal (electric signal) according to the operation signal (electric signal) output from the operation signal generation unit of the boom operation lever 26B. Generate The operation signal output from the operation signal generation unit of the boom operation lever 26B is an electrical signal that changes in accordance with the operation amount and the operation direction of the boom operation lever 26B.

Specifically, when the boom control lever 26B is operated in the boom raising direction, the controller 30 outputs, to the solenoid valve 60, a boom raising operation signal (electric signal) according to the lever operation amount. The solenoid valve 60 adjusts the flow passage area according to the boom raising operation signal (electric signal), and acts on the right side (raising side) pilot port of the control valve 174L and the left side (raising side) pilot port of the control valve 174R. Control the pilot pressure. Similarly, when the boom control lever 26B is operated in the boom lowering direction, the controller 30 outputs a boom lowering operation signal (electric signal) corresponding to the lever operation amount to the solenoid valve 62. The solenoid valve 62 adjusts the flow passage area according to the boom lowering operation signal (electric signal), and controls the pilot pressure applied to the right (lower side) pilot port of the control valve 174R.

When executing the automatic control, the controller 30 controls the boom raising operation signal (electric signal) or the boom lowering according to the correction operation signal (electric signal) instead of the operation signal output from the operation signal generation unit of the boom operation lever 26B. An operation signal (electrical signal) is generated. The correction operation signal may be an electrical signal generated by the controller 30, or may be an electrical signal generated by an external control device or the like other than the controller 30.

FIG. 9 shows another configuration example of the operation system including the electric operation device. Specifically, the operation system of FIG. 9 is another example of a boom operation system, and mainly includes an electromagnetic control valve 17, a boom operation lever 26B as an electric operation lever, and a controller 30. It is configured. The operation system of FIG. 9 may be applied to an arm operation system, a bucket operation system, and the like as well.

The electromagnetic control valve 17 includes a boom control valve, an arm control valve, a bucket control valve, and the like, each of which is configured of an electromagnetic spool valve that operates in response to a command from the controller 30.

The boom operating system of FIG. 9 differs from the boom operating system of FIG. 8 in that the controller 30 directly controls the boom control valve. In the boom operating system of FIG. 8, the controller 30 is configured to indirectly control the control valve 17B (see FIG. 3) via the solenoid valve 60 or the solenoid valve 62.

In the configuration of FIG. 9, when the manual operation is performed, the controller 30 generates a boom operation signal (electric signal) according to the operation signal (electric signal) output from the operation signal generation unit of the boom operation lever 26B.

Specifically, when the boom control lever 26B is operated in the boom raising direction, the controller 30 outputs a boom raising operation signal (electric signal) according to the lever operation amount to the boom control valve. The boom control valve is displaced by a spool stroke amount according to the boom raising operation signal (electric signal), and adjusts the flow rate of the hydraulic fluid flowing into the bottom side oil chamber of the boom cylinder 7. Similarly, when the boom control lever 26B is operated in the boom lowering direction, the controller 30 outputs a boom lowering operation signal (electric signal) corresponding to the lever operation amount to the boom control valve. The boom control valve is displaced by a spool stroke amount according to the boom lowering operation signal (electric signal), and adjusts the flow rate of hydraulic fluid flowing into the rod side oil chamber of the boom cylinder 7.

Thus, the shovel according to the embodiment of the present invention can operate similarly to the case where the hydraulic operating device is adopted even when the electric operating device is adopted.

1 ····················································································································································································································································· By the left traveling hydraulic motor 1R · · · right hydraulic traveling motor 2 · · · turning mechanism 2 A · · · turning hydraulic motor 3 · · · upper revolving unit Boom 5 ··· Arm 6 ··· Bucket 7 ··· Boom cylinder 8 ··· Arm cylinder 9 ··· Bucket cylinder 10 ··· Cabin 11 ···

Engine

13, 13L, 13R ···

Regulator

14, 14L, 14R: Main pump 15: Pilot pump 17:

Control valve

18L, 18R:

Negative control throttle

19L, 19R: Negative control pressure sensor 26: Operating device 26A: Arm operation Lever 26B: Boom control lever 26AV, 26AVL, 26AVR ... remote control 27, 27AL, 27AR ... pressure reducing valve 27A ...

pressure sensor

28, 28L, 28R ... discharge

pressure sensor

29, 29A ... pressure sensor 30 ... controller 31 ... switch 40L, 40R · · · ·

Center bypass line

42L, 42R · · · Parallel line 50 · · · Optional

hydraulic actuator

60, 62 · · · Solenoid valve 171L to 175L, 171R to 175R · · · Control valve 300 · · · Sensitivity adjustment section

Claims

The lower traveling body,
An upper revolving unit mounted on the lower traveling unit,
A driver's cab attached to the upper revolving superstructure;
An operating lever installed in the operator's cab, which can simultaneously operate a plurality of actuators;
A control device for adjusting the sensitivity of the control lever;
Excavator.
The lower traveling body,
An upper revolving unit mounted on the lower traveling unit,
A driver's cab attached to the upper revolving superstructure;
An operating lever installed in the driver's cabin;
When the operating lever is tilted in a first direction or a second direction opposite to the first direction from a neutral position, the control lever is driven in a direction corresponding to the first direction or the second direction 1 actuator,
The third direction or the fourth direction when the control lever is tilted in a third direction substantially orthogonal to the first direction from the neutral position or in a fourth direction opposite to the third direction. A second actuator driven in a direction corresponding to
A controller configured to adjust sensitivity of at least one of the first direction, the second direction, the third direction, and the fourth direction of the operation lever;
Excavator.
The control device adjusts the sensitivity of the operating lever by adjusting the size of the dead zone of the operating lever.
The shovel according to claim 1.
It has a display device for displaying a screen used when switching on / off of the function of adjusting the sensitivity of the operation lever.
The shovel according to claim 1.
The control device adjusts the sensitivity of the control lever according to the state of the control lever.
The shovel according to claim 1.
The control device adjusts the sensitivity of the control lever based on the operation history of the control lever.
The shovel according to claim 1.