CN111465737A

CN111465737A - Excavator

Info

Publication number: CN111465737A
Application number: CN201780097676.9A
Authority: CN
Inventors: 吴春男
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2017-12-14
Filing date: 2017-12-14
Publication date: 2020-07-28
Also published as: WO2019116486A1; JPWO2019116486A1

Abstract

An excavator according to an embodiment of the present invention includes: a lower traveling body (1); an upper revolving body (3) mounted on the lower traveling body (1); an operation room (10) mounted on the upper slewing body (3); an operation rod which is arranged in the control room (10) and can simultaneously operate a plurality of actuators; and a controller (30) for adjusting the sensitivity of the operation lever. The controller (30) adjusts the sensitivity of the joystick, for example, by adjusting the size of the dead zone of the joystick.

Description

Excavator

Technical Field

The present invention relates to a shovel including an operation lever configured to be capable of simultaneously operating a plurality of actuators.

Background

A shovel configured to be able to operate a boom cylinder, an arm cylinder, a bucket cylinder, and a swing motor with 2 levers is known (see patent document 1).

Prior art documents

Patent document

Patent document 1: japanese laid-open patent publication No. 2003-56011

Disclosure of Invention

Technical problem to be solved by the invention

When a trenching operation or the like is performed with the excavator described in patent document 1, an excavator operator may perform a combined operation of a boom lowering operation, an arm closing operation, and a bucket closing operation.

However, for example, in a configuration in which the arm cylinder is operated by operating one operation lever in the front-rear direction and the swing motor is operated by operating in the left-right direction, there is a possibility that the operator may erroneously operate the swing motor when operating the arm cylinder. This is because even if the operation lever is to be correctly operated in the front-rear direction, the operation is slightly performed in the oblique direction.

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

Means for solving the technical problem

An excavator according to an embodiment of the present invention includes: a lower traveling body; an upper revolving body mounted on the lower traveling body; a cab mounted on the upper slewing body; an operation lever that is provided in the cab and is capable of simultaneously operating a plurality of actuators; and a control device for adjusting the sensitivity of the operating lever.

Effects of the invention

In this way, it is possible to provide a shovel that suppresses an erroneous operation in an operation lever configured to be able to simultaneously operate a plurality of actuators.

Drawings

Fig. 1 is a side view of an excavator according to an embodiment of the present invention.

Fig. 2 is a block diagram showing a configuration example of a drive system of the shovel of fig. 1.

Fig. 3 is a schematic diagram showing a configuration example of a hydraulic system mounted on the shovel of fig. 1.

Fig. 4 is a flowchart showing the flow of the sensitivity adjustment processing.

Fig. 5A is a diagram showing a relationship between the lever operation amount of the arm control lever and the pilot pressure.

Fig. 5B is a diagram showing a relationship between the lever operation amount of the arm control lever and the pilot pressure.

Fig. 6 is a view of the operation lever as viewed from directly above.

Fig. 7 is a flowchart of the utilization facilitation process.

Fig. 8 is a diagram showing a configuration example of an operation system including an electric operation device.

Fig. 9 is a diagram showing another configuration example of an operation system including an electric operation device.

Detailed Description

First, a shovel (excavator) as a construction machine according to an embodiment of the present invention will be described with reference to fig. 1. Fig. 1 is a side view of an excavator. An upper turning body 3 is mounted on a lower traveling body 1 of the excavator shown in fig. 1 via a turning mechanism 2. A boom 4 as a work element is attached to the upper slewing body 3. An arm 5 as a work element is attached to a distal end of the boom 4, and a bucket 6 as a work element and a terminal attachment is attached to a distal end of the arm 5. The boom 4, the arm 5, and the bucket 6 constitute an excavation attachment as an attachment. The boom 4, the arm 5, and the bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, respectively. An operation cabin 10 as a cab is provided in the upper slewing body 3, and a power source such as an engine 11 is mounted thereon.

Fig. 2 is a block diagram showing a configuration example of a drive system of the shovel of fig. 1, and a mechanical power transmission line, a hydraulic oil line, a pilot line, and an electric control line are indicated by a double line, a thick solid line, a broken line, and a dotted line, respectively.

The excavator drive system mainly includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve 17, an operation device 26, a pressure reducing valve 27, a discharge pressure sensor 28, a pressure sensor 29, a controller 30, a switch 31, and the like.

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

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

The regulator 13 is a device for controlling the discharge rate of the main pump 14. In the present embodiment, the regulator 13 controls the discharge rate of the main pump 14 by adjusting the swash plate tilt angle of the main pump 14, for example, in accordance with the discharge pressure of the main pump 14, a command current from the controller 30, and the like.

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

Specifically, the control valve 17 includes a plurality of control valves for controlling the flow of hydraulic oil discharged from the main pump 14, and the control valve 17 selectively supplies the hydraulic oil discharged from the main pump 14 to 1 or more hydraulic actuators via these control valves, which control the flow rate of the hydraulic oil flowing from the main pump 14 to the hydraulic actuators and the flow rate of the hydraulic oil flowing from the hydraulic actuators to the hydraulic actuators, and the hydraulic actuators include an arm cylinder 7, an arm cylinder 8, a bucket cylinder 9, a left-side traveling hydraulic motor 1L, a right-side traveling hydraulic motor 1R, and a turning hydraulic motor 2A, and the turning hydraulic motor 2A is an example of a turning device that turns the upper turning body 3 with respect to the lower turning body 1, and may be replaced with an electric turning motor that is an electric actuator.

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

The pressure reducing valve 27 is a device that reduces the pilot pressure generated by the operation device 26 and outputs the reduced pilot pressure. In the present embodiment, the pressure reducing valve 27 increases or decreases the pilot pressure in accordance with a 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 operation device 26. In the present embodiment, the pressure sensor 29 detects, for example, the operating direction and the operating amount of the lever or the pedal of the operating device 26 corresponding to each hydraulic actuator in the form of pressure, and outputs the detected values to the controller 30. Other sensors than the pressure sensor may be used to detect the operation content of the operation device 26.

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

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

The sensitivity adjustment unit 300 is a functional element for adjusting the sensitivity of the operation lever as the operation device 26. In the present embodiment, of the two levers provided in the control cabin 10, the left lever functions as an arm lever and a swing lever, and the right lever functions as a boom lever and a bucket lever. Specifically, the operation of the left lever in the front-rear direction corresponds to the operation of the arm lever, and the operation of the left lever in the left-right direction corresponds to the operation of the swing lever. More specifically, the operation of the left operation lever in the forward direction corresponds to the arm opening operation, and the operation in the backward direction opposite to the forward direction corresponds to the arm closing operation. Further, the operation of the left operation lever in the left direction corresponds to the left turning operation, and the operation in the right direction opposite to the left direction corresponds to the right turning operation. Further, the operation of the right control lever in the front-rear direction corresponds to the operation of the boom control lever, and the operation of the right control lever in the left-right direction corresponds to the operation of the bucket control lever. More specifically, the operation of the right operation lever in the forward direction corresponds to a boom-down operation, and the operation in the backward direction opposite to the forward direction corresponds to a boom-up operation. Further, the operation of the right operation 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 simultaneously operate the arm 5 and the swing device with the left operation lever, and can simultaneously operate the boom 4 and the bucket 6 with the right operation lever. The front-rear direction of the operation lever is substantially orthogonal to the left-right direction.

For example, the sensitivity adjustment unit 300 can reduce the sensitivity of the swing lever while maintaining the sensitivity of the arm lever with respect to the left lever. In this case, even when the operator operates (tilts) the left operation lever in the front-rear direction but operates (tilts) in a slightly tilted direction, the swing device is not operated. This is because it is difficult to reflect the operation of the swing lever by reducing the sensitivity of the swing lever.

The switch 31 is a functional element for switching 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 an in-vehicle display with a touch panel. The switch 31 may be a hardware switch provided in the cage 10.

The operation mode of the excavator includes an erroneous operation prevention mode. The misoperation prevention mode is an operation mode for suppressing or preventing a misoperation of the operation lever. When the malfunction prevention mode is selected, the excavator starts to adjust the sensitivity of the control lever as necessary by the sensitivity adjustment unit 300. With this configuration, the operator can switch between operation and stop of the function of adjusting the sensitivity of the operation lever.

Next, the details of the hydraulic system mounted on the excavator will be described with reference to fig. 3. Fig. 3 is a schematic diagram showing a configuration example of a hydraulic system mounted on the shovel of fig. 1. In the same manner as in fig. 2, fig. 3 shows a mechanical power transmission line, a hydraulic oil line, a pilot line, and an electric control line by a double line, a thick solid line, a broken line, and a dotted line, respectively.

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

main pumps

14L, 14R driven by the engine 11 to the hydraulic oil tank through the

intermediate bypass lines

40L, 40R and the

parallel lines

42L, 42R, the

main pumps

14L, 14R correspond to the main pump 14 of fig. 2.

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

The control valve 171L is a spool valve that switches the flow of hydraulic oil so that the hydraulic oil discharged from the main pump 14L is supplied to the left traveling hydraulic motor 1L and the hydraulic oil discharged from the left traveling hydraulic motor 1L is discharged to a hydraulic oil tank.

Specifically, when the left traveling hydraulic motor 1L and the right traveling hydraulic motor 1R are operated simultaneously with any other hydraulic actuator, the main pump 14L supplies hydraulic oil to both the left traveling hydraulic motor 1L and the right traveling hydraulic motor 1R, and when any other hydraulic actuator is not operated, the main pump 14L supplies hydraulic oil to the left traveling hydraulic motor 1L, and the main pump 14R supplies hydraulic oil to the right traveling hydraulic motor 1R.

The control valve 172L is a spool valve that switches the flow of the working oil so as to supply the working oil discharged by the main pump 14L to the option hydraulic actuator and discharge the working oil discharged by the option hydraulic actuator to the working oil tank, and the option hydraulic actuator 50 is, for example, a grapple open/close cylinder.

The control valve 172R is a spool valve that switches the flow of the hydraulic oil so that the hydraulic oil discharged from the main pump 14R is supplied to the right-side travel hydraulic motor 1R and the hydraulic oil discharged from the right-side travel hydraulic motor 1R is discharged to a hydraulic oil tank.

The control valve 173L is a spool valve that switches the flow of hydraulic oil so that the hydraulic oil discharged from the main pump 14L is supplied to the hydraulic motor 2A for swiveling and the hydraulic oil discharged from the hydraulic motor 2A for swiveling is discharged to a hydraulic oil tank.

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

The

control valves

174L, 174R are spool valves that switch the flow of hydraulic oil so that the hydraulic oil discharged by the

main pumps

14L, 14R is supplied to the boom cylinder 7 and the hydraulic oil in the boom cylinder 7 is discharged to the hydraulic oil tank, in the present embodiment, the control valve 174L is operated only when the boom 4 is lifted and is not operated when the boom 4 is lowered.

The

control valves

175L, 175R are spool valves that switch the flow of hydraulic oil so that hydraulic oil discharged by the

main pumps

14L, 14R is supplied to the arm cylinder 8 and hydraulic oil in the arm cylinder 8 is discharged to a hydraulic oil tank.

The parallel line 42L is a hydraulic oil line parallel to the intermediate bypass line 40L, the parallel line 42L can supply hydraulic oil to a control valve further downstream when the flow of hydraulic oil through the intermediate bypass line 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 intermediate bypass line 40R, and the parallel line 42R can supply hydraulic oil to a control valve further downstream when the flow of hydraulic oil through the intermediate 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 in accordance with the discharge pressures of the

main pumps

14L, 14R, the

regulators

13L, 13R correspond to the regulator 13 of fig. 2, and for example, when the discharge pressures of the

main pumps

14L, 14R become equal to or higher than a predetermined value, the

regulators

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

main pumps

14L, 14R so as to reduce the discharge amounts, in order to prevent the 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 horsepower of the engine 11.

Specifically, when the arm 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 26AV L using the hydraulic oil discharged by the pilot pump 15, and when the arm 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.

Pressure reducing valves 27a L, 27AR are solenoid valves that operate in response to commands from controller 30, and correspond to pressure reducing valve 27 of fig. 2. when arm lever 26A is operated in the closing direction, pressure reducing valve 27a L reduces the pilot pressure generated by remote control valve 26AV L and causes it to act on the right pilot port of control valve 175L and the left pilot port of control valve 175R. when arm lever 26A is operated in the opening direction, pressure reducing valve 27AR reduces the pilot pressure generated by remote control valve 26AVR and causes it to act on the left pilot port of control valve 175L and the right pilot port of control valve 175R.

The pressure sensor 27A is a sensor for detecting the pilot pressure after the pressure reduction by the pressure reducing valves 27A L, 27AR, and outputs the detected value to the controller 30.

The pressure sensor 29A corresponds to the pressure sensor 29 of fig. 2. The pressure sensor 29A detects the content of the operation of the arm lever 26A by the operator 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 swing operation lever (all not shown) are operation devices for operating travel of the lower traveling unit 1, vertical movement of the boom 4, opening and closing of the bucket 6, and swing of the upper swing body 3, respectively. These operating devices apply pilot pressures corresponding to the lever operation amounts (or pedal operation amounts) to any of the left and right pilot ports of the control valves corresponding to the respective hydraulic actuators, using the hydraulic oil discharged from the pilot pump 15, as in the case of the arm operation lever 26A. Similarly to the pressure sensor 29A, the operation contents of the respective operation devices by the operator are detected as pressures by the corresponding pressure sensors, and the detected values are output to the controller 30.

Fig. 3 shows only the arm control lever 26A and its pilot conduit for clarity, but in practice, a boom control lever, a bucket control lever, a swing control lever, and the like are similarly connected to the pilot port of the corresponding control valve via the pilot conduit.

Here, the negative control employed in the hydraulic system of fig. 3 will be described.

The

intermediate bypass lines

40L, 40R are provided with

negative control restrictors

18L, 18R between each of the

control valves

175L, 175R located most downstream and the hydraulic oil tank, the flow of the hydraulic oil discharged by the

main pumps

14L, 14R is restricted by the

negative control restrictors

18L, 18R, and the

negative control restrictors

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

regulators

13L, 13R.

The negative

control pressure sensors

19L, 19R are sensors that detect the negative control pressure generated upstream of the

negative control restrictors

18L, 18R in the present embodiment, the negative

control pressure sensors

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

The controller 30 outputs commands corresponding to the negative pilot pressures to the

regulators

13L, 13R, and the

regulators

13L, 13R control the discharge rates of the

main pumps

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

main pumps

14L, 14R in accordance with the commands, and specifically, the

regulators

13L, 13R decrease the discharge rates of the

main pumps

14L, 14R as the negative pilot pressure increases, and increase the discharge rates of the

main pumps

14L, 14R as the negative pilot pressure decreases.

When none of the hydraulic actuators is operated (hereinafter, referred to as "standby mode"), the hydraulic oil discharged from the

main pumps

14L, 14R reaches the

negative control restrictors

18L, 18R through the

intermediate bypass lines

40L, 40R, and the negative control pressure generated upstream of the

negative control restrictors

18L, 18R is increased by the flow of the hydraulic oil discharged from the

main pumps

14L, 14R, and as a result, the

regulators

13L, 13R reduce the discharge amounts of the

main pumps

14L, 14R to the allowable minimum discharge amount, thereby suppressing the pressure loss (suction loss) when the discharged hydraulic oil passes through the

intermediate bypass lines

40L, 40R.

On the other hand, when any of the hydraulic actuators is operated, the hydraulic oil discharged from 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, and the control valve reduces or eliminates the amount of the hydraulic oil reaching the

negative control restrictors

18L, 18R and reduces the negative control pressure generated upstream of the

negative control restrictors

18L, 18R, and as a result, the

regulators

13L, 13R increase the discharge amount of the

main pumps

14L, 14R, and circulate a sufficient amount of hydraulic oil in the hydraulic actuator to be operated, thereby ensuring the drive of the hydraulic actuator to be operated.

According to the configuration described above, the hydraulic system of fig. 3 can suppress wasteful energy consumption in the

main pumps

14L, 14R in the standby mode, the wasteful energy consumption including the suction loss in the

intermediate bypass lines

40L, 40R by the working oil discharged from the

main pumps

14L, 14R.

In the hydraulic system of fig. 3, when the hydraulic actuator is operated, a sufficient amount of hydraulic oil required can be reliably supplied from the

main pumps

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

Next, a process of adjusting the sensitivity of the operation lever by the controller 30 (hereinafter referred to as "sensitivity adjustment process") will be described with reference to fig. 4. Fig. 4 is a flowchart showing the flow of the sensitivity adjustment processing. In the example of fig. 4, the sensitivity adjustment processing of the left control lever that functions as the arm control lever 26A and the swing control lever will be described. However, the following description is also applicable to the right operation lever that functions as the boom operation lever and the bucket operation lever.

First, the sensitivity adjustment unit 300 of the controller 30 determines whether or not the malfunction prevention mode is set (step S T1). The misoperation prevention mode is selected by an operation input by an operator via the switch 31, for example. The sensitivity adjustment unit 300 can automatically select the malfunction prevention mode when a predetermined condition is satisfied.

When it is determined that the mode is the erroneous operation prevention mode (yes at step ST 1), the sensitivity adjustment unit 300 compares the lever operation amount of the arm operation lever 26A with the operation amount of the swing operation lever, and determines whether or not the lever operation amount of the arm operation lever 26A is equal to or greater than an amount obtained by adding a predetermined amount α to the lever operation amount of the swing operation lever (step ST 2). the predetermined amount α is an amount preset in the controller 30 or the like, and is used, for example, to determine whether or not the lever operation amount of the arm operation lever 26A is significantly greater than the lever operation amount of the swing operation lever.

When it is determined that the lever operation amount of the arm lever 26A is smaller than the amount obtained by adding the predetermined amount α to the lever operation amount of the swing lever (no at step ST2), the sensitivity adjustment unit 300 compares the lever operation amount of the arm lever 26A with the lever operation amount of the swing lever, and determines whether or not the lever operation amount of the swing lever is equal to or larger than the amount obtained by adding the predetermined amount α to the lever operation amount of the arm lever 26A (step ST 3).

When it is determined that the lever operation amount of the swing lever is equal to or greater than the amount obtained by adding a predetermined amount α to the lever operation amount of the arm lever 26A (yes at step ST3), the sensitivity adjustment unit 300 decreases the sensitivity of the arm lever 26A (step ST 4). for example, the sensitivity adjustment unit 300 outputs a control command to each of the pressure reducing valves 27a L and 27AR shown in fig. 3 to decrease the pilot pressure generated by the arm lever 26A.

By this processing, even when the operator intends to operate the left operation lever in the right direction to perform right turning but operates the left operation lever in a slightly diagonally forward right direction, it is possible to suppress or prevent the opening of the arm 5. This is because the inadvertently increased stick opening side pilot pressure can be reduced.

When it is determined that the lever operation amount of the swing lever is smaller than the amount obtained by adding the predetermined amount α to the lever operation amount of the arm lever 26A (no at step ST3), the sensitivity adjustment unit 300 executes normal control (step ST5) without adjusting the lever sensitivity because it can be determined that the difference between the lever operation amount of the swing lever and the lever operation amount of the arm lever 26A is smaller than the predetermined amount α, that is, the swing lever and the arm lever 26A are simultaneously operated at substantially the same lever operation amount, and it is not necessary to adjust the lever sensitivity.

On the other hand, when it is determined that the lever operation amount of the arm lever is equal to or greater than the amount obtained by adding the predetermined amount α to the lever operation amount of the swing lever (yes in step ST2), the sensitivity adjustment unit 300 decreases the sensitivity of the swing lever (step ST 6).

By this processing, even when the operator operates the left operation lever in a slightly backward oblique direction to the left in order to close the arm while attempting to operate the left operation lever in the backward direction (near side), the left turning of the upper turning body 3 can be suppressed or prevented. This is because the left-turn side pilot pressure that increases unintentionally can be reduced.

In the example of fig. 4, the sensitivity adjustment unit 300 automatically reduces the sensitivity of the operation lever having a small lever operation amount. However, the present invention is not limited to this structure. For example, the operator may set the desired sensitivity of the operation lever so that the desired sensitivity is lowered to a desired level. For example, the operator may set the sensitivity of a specific operation lever by using the switch 31 so as to lower the sensitivity, or may set the degree of reduction in detail. For example, the operator may greatly reduce the sensitivity of a joystick that is not intended to be moved.

Next, a specific method of adjusting the sensitivity of the control lever will be described with reference to fig. 5A and 5B, where fig. 5A and 5B are both diagrams showing a relationship between a detected value (hereinafter referred to as "1 st-side pilot pressure") of the pressure sensor 29A indicating the lever operation amount of the arm control lever 26A and a detected value (hereinafter referred to as "2 nd-side pilot pressure") of the pressure sensor 27A, where 1 st-side pilot pressure is a pilot pressure on an upstream side (on the arm control lever 26A side) of the pressure reducing valves 27A L, 27AR, and 2 nd-side pilot pressure is a pilot pressure on a downstream side (on the

control valves

175L, 175R sides) of the pressure reducing valves 27A L, 27AR, and where the lever operation amount can be calculated from the 1 st-side pilot pressure and the characteristics of the remote control valve 26AV, where the 1 st-side pilot pressure is actually represented by a positive value, where for convenience of description in fig. 5A and 5B, the 1 st-side pilot pressure in the arm opening direction is represented by a positive value, the negative value in the horizontal axis represents the pilot pressure before the adjustment, and the left-side pilot pressure represents the pilot pressure (on the left-side pilot pressure) and the horizontal axis represents the pilot pressure before the adjustment, where the pilot pressure represents the pilot pressure, the pilot pressure in the left-side of the arm opening direction, and the pilot pressure, the pilot pressure represents the.

Fig. 5A shows a method of reducing the sensitivity of the arm lever 26A by expanding the dead zone of the arm lever 26A, specifically, a method of displacing the 2 nd side pilot pressure by the pressure reducing valve according to the lever operation amount, the dead zone refers to a range that is regarded as zero even if the lever operation amount is not actually zero, the sensitivity adjustment unit 300 outputs a command to the pressure reducing valve 27a L and the pressure reducing valve 27AR to expand the dead zone of the range W1 of the 1 st side pilot pressure-L1 to + L to the range W2 of the 1 st side pilot pressure-L to + L, so that if the 1 st side pilot pressure on the opening side of the arm lever 26A is 0 to + L, the 2 nd side pilot pressure acting on the arm opening side port is maintained at a level that does not displace the control valve L and the control valve 175R from the neutral position, similarly, if the 1 st side pilot pressure on the closing side of the arm lever operation lever 26A is-5, the open side pilot pressure is maintained at the same level as the neutral pressure, and the open side pilot valve 175R 2 is maintained at the same level as the dead zone of the closed side pilot lever closing side of the arm lever operation lever 26A, but the open side pilot valve 175 and the open side is maintained at the same level of the neutral side of the dead zone 175, and the dead zone 175, thus, the open side pilot valve 175, which is maintained at the same level, and the same, and the dead zone, the open side of the dead zone, the open.

Fig. 5B shows a method of reducing the sensitivity of the arm lever 26A by reducing the rate of increase of the 2 nd-side pilot pressure with respect to the 1 st-side pilot pressure of the arm lever 26A, specifically, a method of changing the rate of increase (slope) of the 2 nd-side pilot pressure with a pressure reducing valve according to the lever operation amount, the sensitivity adjustment unit 300 outputs a command to the pressure reducing valve 27a L and the pressure reducing valve 27AR to reduce the rate of increase of the 2 nd-side pilot pressure with respect to the 1 st-side pilot pressure when the arm lever 26A is operated in the opening direction from θ 1 to θ 2, and therefore, the 2 nd-side pilot pressure that starts to increase when the 1 st-side pilot pressure is + L1 and reaches the maximum value at + L2 is not + L2 but reaches the maximum value at a later when + L3, and the same is true when the arm lever operation lever 26A is operated in the closing direction, and in the example of fig. 5B, the arm opening side and the arm closing side can be changed only at the same slope (θ 1 — 2), but the arm opening rate and the arm closing rate can be changed to be different.

Thus, the sensitivity adjustment section 300 controls the pressure reducing valve 27a L and the pressure reducing valve 27AR to change the relationship between the 1 st-side pilot pressure and the 2 nd-side pilot pressure, thereby adjusting the sensitivity of the operation lever, so that the arm 5 does not open even if the left operation lever is inadvertently tilted in the arm opening direction when the operator wants to operate the left operation lever only in the turning direction, and as a result, the operator can be prevented from performing an undesired arm opening operation, and the same is true for the other operation levers, although the description is made for the arm operation lever 26A in fig. 5A and 5B.

Next, the mishandling rate will be described with reference to fig. 6. Fig. 6 is a view of the left control lever as viewed from directly above, with the vertical axis corresponding to the operation direction of the arm control lever 26A and the horizontal axis corresponding to the operation direction of the swing control lever.

The hatched area in fig. 6 indicates the dead zone. Specifically, a hatched area extending in the lateral direction indicates a dead zone of the arm lever 26A, and a hatched area extending in the longitudinal direction indicates a dead zone of the swing lever. The dot pattern region of fig. 6 represents a micro manipulation region. Specifically, the dot pattern region extending in the lateral direction indicates a micro-operation region of the arm lever 26A, and the dot pattern region extending in the longitudinal direction indicates a micro-operation region of the swing lever.

The lever position P0 shows a state in which the left operating lever is at the neutral position, and the lever position P1 shows a state in which the swing operating lever is operated in the left swing direction as intended by the operator.

The lever position P2 represents a state in which the swing lever is operated in the rightward swing direction as intended by the operator and the arm lever 26A is operated in the closing direction.

The lever position P3 represents a state in which the swing lever is operated in the rightward swing direction as intended by the operator, but the arm lever 26A is erroneously operated in the opening direction in the opposite direction to the intention of the operator.

The lever position P4 represents a state in which the arm lever 26A is operated in the opening direction as intended by the operator, but the swing lever is erroneously operated in the leftward swing direction opposite to the intended operation by the operator.

In the above example, the states indicated by the respective positions of the lever position P3 and the lever position P4 indicate the state in which the erroneous operation is performed. That is, in the above example, the state in which the erroneous operation is performed includes the state in which the swing lever is operated a little when the arm lever 26A is operated beyond the micro-operation region (the state indicated by the lever position P4). Further, the state (the state indicated by the lever position P3) is included in which the arm lever 26A is operated in a micro-operation when the swing lever is operated beyond the micro-operation region.

In the normal control, the mishandling rate is calculated from the statistical value of the time (time of performing the mishandling) during which the micro-manipulation region is manipulated as shown in fig. 6, for a predetermined time. For example, the operation time 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, a time when the operation lever is present at a position other than the neutral position or a time when the operation lever is present at a position other than the dead zone. The malfunction time is, for example, a time in a state where a malfunction is performed. The mishandling rate may be derived as a ratio of the number of times of mishandling to the total number of times of handling of the operation lever, or may be derived by another method. The 1-time operation of the control lever is, for example, an operation until the control lever returns to the neutral position after leaving the neutral position. The controller 30 can not only calculate the mishandling rate but also grasp the characteristics of the lever operation that the operator is likely to mishandle. For example, the controller 30 can grasp, for each operator, a tendency that a certain operator unintentionally tilts the left control lever in the rightward turning direction only when the operator wants to close the arm. In this case, the controller 30 may simply decrease the sensitivity to the right swing operation. That is, the normal control does not need to be changed with respect to the sensitivity to the left swing operation.

Next, a process of the controller 30 prompting the operator to use the erroneous operation prevention mode (hereinafter, referred to as "use promotion process") will be described with reference to fig. 7. Fig. 7 is a flowchart of the utilization facilitation process. The controller 30 repeatedly executes the utilization promoting process at a predetermined control cycle.

First, the controller 30 determines whether or not the operation error rate is equal to or greater than a predetermined threshold (step ST 11). For example, the controller 30 stores the operation contents of the operation lever in time series. Then, the operation error rate is derived from the operation history for a predetermined time. The predetermined time is, for example, a predetermined time (for example, 1 hour) after the engine is started. Then, it is determined whether or not the malfunction rate in the predetermined time is equal to or greater than a threshold value.

If it is determined that the malfunction rate is equal to or greater than the threshold value (yes at step ST11), the controller 30 prompts the use of the malfunction prevention mode (step ST 12). For example, the controller 30 displays text information 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 malfunction prevention mode by pressing the switch 31. Voice information promoting the use of the malfunction prevention mode may also be output from the in-vehicle speaker.

The controller 30 may automatically start the malfunction prevention mode. In this case, the controller 30 may display an image indicating that the vehicle is in the malfunction prevention mode on a screen of the display device, or may periodically output the voice information indicating that the vehicle is in the malfunction prevention mode from the vehicle-mounted speaker. The voice information indicating the start of the malfunction prevention mode may be output from the in-vehicle speaker.

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

If it is determined that the operation error rate is smaller than the threshold value (no in step ST11), the controller 30 ends the present usage promotion process without promoting the usage misoperation prevention mode.

In this way, the controller 30 can derive the mishandling rate from the operation history of the operation lever, and if the mishandling rate is equal to or greater than the predetermined threshold, the operator can be prompted to use the mishandling prevention mode, or the mishandling prevention mode can be automatically started.

The controller 30 can change the adjustment content of the sensitivity of the operation lever according to the misoperation rate. Therefore, it is possible to perform appropriate sensitivity adjustment corresponding to the frequency of the erroneous operation. Further, the operator can grasp the operation characteristics, and can determine the lever operation direction and the sensitivity adjustment amount, in which the sensitivity should be changed, based on the characteristics.

According to the above configuration, the controller 30 suppresses or prevents the erroneous turning operation from being performed when the arm is operated in the sequential operation such as the trenching operation in a narrow space. Therefore, the excavator can be prevented or prevented from erroneously contacting the surrounding ground. As a result, the safety, operability, and work efficiency of the excavator can be improved.

The preferred embodiments of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiments. The above embodiments may be applied to respective modifications, replacements, and the like without departing from the scope of the present invention. Further, the features described individually can be combined as long as no technical contradiction occurs.

For example, in the above-described embodiment, the sensitivity adjustment section 300 automatically reduces the sensitivity of the operation lever having a small lever operation amount. However, the present invention is not limited to this structure. For example, as shown in fig. 6, the sensitivity adjustment unit 300 determines whether or not the micromanipulation region is in the state of performing the erroneous operation, and can automatically lower the sensitivity of the operation lever having a small lever operation amount only when it is determined that the erroneous operation is performed. That is, in the erroneous operation prevention mode, when it is determined that the erroneous operation has not been performed, the sensitivity of the operation lever with a small lever operation amount can be maintained without being lowered.

In the above embodiment, the hydraulic operation device is used as the operation device 26, but an electric operation device may be used. 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 is mainly configured by a pilot pressure operation type control valve 17, a boom operation lever 26B that is an electric operation lever, a controller 30, a boom-up operation solenoid valve 60, and a boom-down operation solenoid valve 62. The operation system of fig. 8 can be similarly applied to an arm operation system, a bucket operation system, and the like.

As shown in fig. 3, the pilot pressure operated control valve 17 includes

control valves

174L, 174R relating to the boom cylinder 7, the solenoid valve 60 is configured to be able to adjust the flow passage area of the oil passage connecting the pilot pump 15 to each of the right (lift side) pilot port of the control valve 174L and the left (lift side) pilot port of the control valve 174R, and the solenoid valve 62 is configured to be able to adjust the flow passage area of the oil passage connecting the pilot pump 15 to the right (lower side) pilot port of the control valve 174R.

When the manual operation is performed, the controller 30 generates a boom raising operation signal (electric signal) or a boom lowering operation signal (electric signal) based on an operation signal (electric signal) output from the operation signal generating unit of the boom control lever 26B. The operation signal output from the operation signal generating unit of the boom control lever 26B is an electric signal that changes in accordance with the operation amount and the operation direction of the boom control lever 26B.

Specifically, when the boom operation lever 26B is operated in the boom-up direction, the controller 30 outputs a boom-up operation signal (electrical signal) corresponding to the lever operation amount to the solenoid valve 60, the solenoid valve 60 adjusts the flow path area in accordance with the boom-up operation signal (electrical signal) and controls the pilot pressure acting on the right (lift-side) pilot port of the control valve 174L and the left (lift-side) pilot port of the control valve 174R, similarly, when the boom operation lever 26B is operated in the boom-down direction, the controller 30 outputs a boom-down operation signal (electrical signal) corresponding to the lever operation amount to the solenoid valve 62, and the solenoid valve 62 adjusts the flow path area in accordance with the boom-down operation signal (electrical signal) and controls the pilot pressure acting on the right (lower) pilot port of the control valve 174R.

In the case of performing the automatic control, the controller 30 generates a boom-up operation signal (electrical signal) or a boom-down operation signal (electrical signal) in accordance with the correction operation signal (electrical signal) instead of the operation signal output by the operation signal generating part of the boom manipulation lever 26B. The correction operation signal may be an electric signal generated by the controller 30, or may be an electric signal generated by an external control device or the like other than the controller 30.

Fig. 9 shows another configuration example of an operation system including an electric operation device. Specifically, the operation system of fig. 9 is another example of a boom operation system, and is mainly configured by the electromagnetic work type control valve 17, the boom operation lever 26B as an electric operation lever, and the controller 30. The operation system of fig. 9 can be similarly applied to an arm operation system, a bucket operation system, and the like.

The solenoid-operated control valve 17 includes a boom control valve, an arm control valve, a bucket control valve, and the like, each of which is configured by a solenoid spool valve that operates in accordance with a command from the controller 30.

The boom manipulation system of fig. 9 is different from the boom manipulation system of fig. 8 in that the controller 30 directly controls the boom control valve. In the boom operation system of fig. 8, the controller 30 is configured to indirectly control the control valve 17B via the solenoid valve 60 or the solenoid valve 62 (refer to fig. 3).

In the configuration of fig. 9, when a manual operation is performed, the controller 30 generates a boom operation signal (electric signal) based on an operation signal (electric signal) output from the operation signal generating unit of the boom control lever 26B.

Specifically, when the boom manipulating lever 26B is manipulated in the boom raising direction, the controller 30 outputs a boom raising manipulation signal (electric signal) corresponding to the lever manipulation amount to the boom control valve. The boom control valve displaces only the spool stroke amount corresponding to the boom raising operation signal (electric signal) and adjusts the flow rate of the hydraulic oil flowing into the bottom side oil chamber of the boom cylinder 7. Similarly, when the boom manipulating lever 26B is manipulated in the boom-down direction, the controller 30 outputs a boom-down manipulation signal (electric signal) corresponding to the lever manipulation amount to the boom control valve. The boom control valve displaces only the spool stroke amount corresponding to the boom-down operation signal (electric signal) and adjusts the flow rate of the hydraulic oil flowing into the rod-side oil chamber of the boom cylinder 7.

As described above, the shovel according to the embodiment of the present invention can operate in the same manner as the case of using the hydraulic operation device even when the electric operation device is used.

Description of the symbols

1-lower traveling body, 1L-left traveling hydraulic motor, 1R-right traveling hydraulic motor, 2-slewing mechanism, 2A-slewing hydraulic motor, 3-upper slewing body, 4-boom, 5-arm, 6-bucket, 7-boom cylinder, 8-arm cylinder, 9-bucket cylinder, 10-control room, 11-engine, 13L, 13R-regulator, 14L, 14R-main pump, 15-pilot pump, 17-control valve, 18L, 18R-negative control restrictor, 19L, 19R-negative control pressure sensor, 26-operating device, 26A-arm operating rod, 26B-boom operating rod, 26AV L, 26R-remote control valve, 27A L, 27 AR-pressure reducing valve, 27A-pressure sensor, 28L, 28R-discharge pressure sensor, 29A-29-pressure sensor, 30-AVR-remote control valve, 30-48340-AVR-remote control valve, 175-21R-hydraulic pressure sensor, 175-200R-hydraulic pressure regulator, 175-200R-hydraulic pressure regulator, electromagnetic valve.

Claims

1. A shovel is provided with:

a lower traveling body;

an upper revolving body mounted on the lower traveling body;

a cab mounted on the upper slewing body;

an operation lever that is provided in the cab and is capable of simultaneously operating a plurality of actuators; and

and a control device for adjusting the sensitivity of the operating lever.

2. A shovel is provided with:

a lower traveling body;

an upper revolving body mounted on the lower traveling body;

a cab mounted on the upper slewing body;

an operation lever provided in the cab;

a 1 st actuator that is driven in a direction corresponding to a 1 st direction or a 2 nd direction opposite to the 1 st direction when the operating lever is tilted from a neutral position in the 1 st direction or the 2 nd direction;

a 2 nd actuator that is driven in a direction corresponding to the 3 rd direction or the 4 th direction when the operating lever is tilted from a neutral position in the 3 rd direction substantially orthogonal to the 1 st direction or the 4 th direction opposite to the 3 rd direction; and

a control device that adjusts sensitivity with respect to at least 1 direction of the 1 st direction, the 2 nd direction, the 3 rd direction, and the 4 th direction of the operation lever.

3. The shovel of claim 1,

the control device adjusts the sensitivity of the lever by adjusting the size of the insensitive area of the lever.

4. The shovel according to claim 1, comprising:

and a display device for displaying a screen used when switching between operation and stop of the function for adjusting the sensitivity of the operation lever.

5. The shovel of claim 1,

the control device adjusts the sensitivity of the operating lever according to the state of the operating lever.

6. The shovel of claim 1,

the control device adjusts the sensitivity of the operating lever according to the operation history of the operating lever.