JP6576757B2 - Excavator - Google Patents

Description

  The present invention relates to an excavator.

  The excavator includes a traveling body called a crawler, an upper swing body, a swing device that rotates the upper swing body with respect to the travel body, and an attachment attached to the upper swing body. FIG. 1A is a diagram showing a cockpit 100 of an excavator. The cockpit is provided with a left operation lever 102 and a right operation lever 103 operated by an operator (operator). FIG. 1B is a diagram showing the left operation lever 102. The front-rear direction (i) and the left-right direction (ii) of the left operation lever 102 are each assigned to one of a turning axis, an arm axis, a boom axis, and a bucket axis. The same applies to the right and left direction and the front and rear direction of the right operation lever 103. The correspondence between the lever direction and the shaft differs depending on the excavator manufacturer.

  The correspondence relationship (referred to as sensitivity characteristics in this specification) of the control command (and thus the actual operation) with respect to the tilt angle of the lever differs for each model (size / manufacturer). This sensitivity characteristic is directly related to the operational feeling of the shovel. However, when an excavator having an operational feeling different from that experienced by the operator is used, problems such as a decrease in work accuracy and an increase in work time occur.

JP 2002-326881 A Japanese Patent Laid-Open No. 8-151662 JP-A-1-156300 JP 7-77206 A

  The present invention has been made in view of the above problems, and one of the exemplary purposes of an aspect thereof is to provide an excavator capable of providing an operation feeling suitable for each operator or for each work.

  One embodiment of the present invention relates to an excavator. The excavator is provided in a traveling body, an upper revolving body that turns relative to the traveling body, an attachment that is attached to the upper revolving body, and a driver seat of the upper revolving body. The control lever that is associated with the movement of the control shaft, which is one of the boom shaft, arm shaft, and bucket shaft, and the sensitivity characteristic that indicates the correspondence between the tilt angle of the control lever and the command value specified in advance are maintained, A sensitivity correction unit that generates a command value according to the angle and a drive device that controls the control axis according to the command value are provided. A sensitivity correction | amendment part produces | generates a sensitivity characteristic so that the at least 2 coordinate previously input by the operator may be passed.

  By enabling the operator to set the sensitivity characteristic, it is possible to provide an appropriate operational feeling for each operator or operation. Further, since at least two coordinates can be designated, gain, sensitivity, rise characteristic and saturation characteristic can be set independently, and the operational feeling can be brought close to the operator's preference.

The sensitivity correction unit has a GUI (Graphical User Interface), and accepts input of at least two coordinates by the operator while displaying sensitivity characteristics on the display means.
As a result, the operator can intuitively set the sensitivity characteristic.

The sensitivity correction unit may hold a plurality of different sensitivity characteristics corresponding to a plurality of operations. The sensitivity correction unit may generate a command value based on the sensitivity characteristic corresponding to the work selected by the operator.
As a result of studies by the present inventor, preferred sensitivity characteristics differ depending on the type of work such as excavation work, leveling work, and loading work. According to this aspect, the efficiency of each work can be increased.

  The sensitivity correction unit may have a GUI (Graphical User Interface), display a plurality of operations on the display unit, and accept selection of operations by the operator.

Another aspect of the present invention also relates to an excavator. The excavator is provided in a traveling body, an upper revolving body that turns relative to the traveling body, an attachment that is attached to the upper revolving body, and a driver seat of the upper revolving body. The control lever that is associated with the movement of the control shaft, which is one of the boom axis, arm axis, and bucket axis, and a plurality of sensitivity characteristics corresponding to a plurality of operations are maintained. This indicates the correspondence with the command value, and controls the control axis according to the command value and the sensitivity correction unit that generates the command value according to the tilt angle based on the sensitivity characteristics corresponding to the work selected by the operator A driving device.
According to this aspect, sensitivity characteristics suitable for work can be provided, and work efficiency can be increased.

  Note that any combination of the above-described constituent elements and the constituent elements and expressions of the present invention replaced with each other among methods, apparatuses, systems, and the like are also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the operation feeling suitable for every operator or every work can be provided.

FIG. 1A is a view showing a cockpit of an excavator, and FIG. 1B is a view showing a left operation lever. It is a perspective view which shows the external appearance of the shovel which is an example of the construction machine which concerns on embodiment. It is a control block diagram of the shovel which concerns on embodiment. It is a figure which shows an example of a sensitivity characteristic. It is a figure which shows GUI. FIGS. 6A and 6B are diagrams for explaining sensitivity correction of the shovel according to the embodiment. FIG. 7A is a waveform diagram of a speed command, and FIG. 7B is a diagram showing sensitivity characteristics. 8A to 8E are diagrams illustrating an example of sensitivity characteristics for each work mode. FIG. 9A shows a leveling work, and FIG. 9B shows a shovel that performs excavation (deep digging) work. It is a figure which shows the display means at the time of work mode selection. It is a block diagram, such as an electric system and a hydraulic system, of the excavator according to the embodiment. It is a figure which shows the sensitivity characteristic which concerns on a modification.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, members, and processes shown in the drawings are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate. The embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  In this specification, “the state in which the member A is connected to the member B” means that the member A and the member B are electrically connected to each other in addition to the case where the member A and the member B are physically directly connected. It includes cases where the connection is indirectly made through other members that do not substantially affect the general connection state, or that do not impair the functions and effects achieved by their combination.

  FIG. 2 is a perspective view illustrating an appearance of an excavator 1 that is an example of the construction machine according to the embodiment. The excavator 1 mainly includes a traveling body (crawler) 2 and an upper revolving body (hereinafter also simply referred to as an upper revolving body) 4 that is rotatably mounted on an upper portion of the traveling body 2 via a revolving mechanism 3. Yes.

  A boom 5, an arm 6 linked to the tip of the boom 5, and a bucket 10 linked to the tip of the arm 6 are attached to the upper swing body 4. The bucket 10 is a facility for capturing suspended loads such as earth and sand and steel materials. The boom 5, the arm 6, and the bucket 10 are collectively referred to as an attachment 12, and are hydraulically driven by the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, respectively. Further, the upper swing body 4 is provided with a power source such as an operator cab 4 a for accommodating an operator who operates the position of the bucket 10, excitation operation and release operation, and an engine 11 for generating hydraulic pressure. The engine 11 is composed of, for example, a diesel engine.

  FIG. 3 is a control block diagram of the excavator 1 according to the embodiment. FIG. 3 shows only one specific axis. The shovel 1 includes an operation lever 500, a sensitivity correction unit 502, a driving device 504, and a control shaft 506.

  The operation lever 500 is provided in the driver seat of the upper swing body. The operation lever 500 can tilt in the vertical direction and the horizontal direction. In the operation lever 500, tilting in a certain direction is associated with movement of one of the swing axis, the boom axis of the attachment, the arm axis, and the bucket axis (hereinafter referred to as a control axis). For example, the tilt angle θ corresponds to the speed of the control axis. The tilt angle θ of the operation lever 500 is converted into an electric signal and input to the sensitivity correction unit 502.

The sensitivity correction unit 502 holds a sensitivity characteristic 511 (tilt angle vs. command value characteristic) indicating a correspondence relationship between the tilt angle θ of the operation lever 500 defined in advance and the command value ω _REF with respect to the control axis. A command value ω _REF corresponding to θ is generated.

  The sensitivity correction unit 502 includes a calculation unit 510 and a user interface 512. The user interface 512 may be a GUI (Graphical User Interface) having an input unit 514 such as a button, a volume knob, a joystick, or a touch panel, and a display unit such as a liquid crystal display. Prior to work, the operator inputs at least two coordinates of the sensitivity characteristic 511 via the input means 514.

  The calculation unit 510 generates the sensitivity characteristic 511 so as to pass at least two coordinates input in advance by the operator. The sensitivity characteristic 511 is held in the calculation unit 510 in the form of a table or an arithmetic expression (approximation expression). The calculation unit 510 can be realized by a combination of hardware such as a CPU (Central Processing Unit), a microcomputer, a DSP (Digital Signal Processor), and a software program, or a dedicated controller.

FIG. 4 is a diagram illustrating an example of the sensitivity characteristic 511. The sensitivity characteristic 511 is divided into a dead zone 520, a transition zone 522, and a peak zone 524 according to the tilt angle θ of the lever. 0 <θ <θ ₁ is a dead zone 520 where the velocity ω _REF is zero, θ ₁ <θ <θ ₂ is a transition region where the velocity increases according to the tilt angle θ, and θ ₂ <θ <θ _MAX is This is a peak region 524 where the speed is the maximum value ω _MAX . The sensitivity correction unit 502 receives input of the first coordinate P1 at the boundary between the dead zone 520 and the transition region 522 and the second coordinate P2 at the boundary between the transition region 522 and the peak region 524, and the transition region 522 has the first coordinate P1 and the first coordinate. You may prescribe | regulate by the linear function which passes 2 coordinate P2. The boundaries θ ₁ and θ ₂ may be fixed or may be changed by the operator. The dead zone 520 and the vicinity of the peak region 524 may be automatically corrected, for example, a perpendicular line or may be obtained by spline interpolation.

  When the operator inputs the first coordinate P1 and the second coordinate P2, a constraint condition is imposed so that the slope is positive in the transition area 522, and an input that violates this condition is disabled or violated. It is desirable to alert the operator. In addition, it is desirable to set an allowable range (hatching) 526 in which the first coordinate P1 and the second coordinate P2 can be selected so that a dangerous area or an area where the operational feeling is clearly impaired cannot be selected.

  The sensitivity correction unit 502 has a GUI (Graphical User Interface), and accepts input of at least two coordinates P1 and P2 by the operator while displaying the sensitivity characteristic 511 of FIG. FIG. 5 is a diagram showing a GUI. The GUI can use a display provided for the purpose of machine guidance in the cab. The operator can visually and intuitively specify the two coordinates P1 and P2 by touching the screen with the finger 530. Alternatively, the coordinates P1 and P2 may be moved up and down (and / or left and right) by rotating the volume knob.

Returning to FIG. The driving device 504 controls the control axis 506 of the control axis according to the command value ω _REF output from the sensitivity correction unit 502. The control shaft 506 corresponds to (i) a boom shaft cylinder, (ii) an arm shaft cylinder, (iii) a bucket shaft cylinder, or (iv) a swing motor.

  The above is the configuration of the excavator 1. Next, the operation will be described. 6A and 6B are diagrams for explaining sensitivity correction of the excavator 1 according to the embodiment. FIG. 6A shows a sensitivity characteristic, and a characteristic A shows a default sensitivity characteristic. The valve pressure on the vertical axis is nothing but the speed command (or torque command) of the arm shaft. FIG. 6B shows the time waveform X of the tilt angle θ of the arm lever when a skilled professional operator performs leveling work based on the default sensitivity characteristic A, and an unfamiliar amateur operator performs leveling work. The time waveform Y of the tilt angle θ of the arm lever when performed is shown. As can be seen from the waveform X, a professional operator operates the arm lever smoothly. On the other hand, in the waveform Y of the amateur operator, the tilt angle θ of the arm lever fluctuates up and down. This is because the sensitivity is too high in the region where the tilt angle θ is large.

  In such a case, as shown in the characteristic B of FIG. 6A, the operator has two coordinates P1, P2 so that the sensitivity is lowered in a region where the tilt angle θ is large, in other words, the tilt is reduced. Can be specified. Specifically, an operation feeling suitable for an amateur operator can be provided by increasing the valve pressure (speed command) at the first coordinate P1. Although the arm shaft has been described here, correction can also be performed for the boom shaft. On the other hand, if the coordinates P1 and P2 are designated as in the characteristic C, the sensitivity can be increased.

  Thus, according to the shovel 1 which concerns on embodiment, an operator can provide suitable operation feeling for every operator because an operator sets a sensitivity characteristic.

  In particular, since at least two coordinates can be specified for the sensitivity characteristics, gain, sensitivity, rise characteristics near the boundary between the dead zone and the transition area, and saturation characteristics near the boundary between the transition area and the peak area are preferred by the operator. It becomes possible to approach.

  FIG. 7A is a waveform diagram of a speed command, and FIG. 7B is a diagram showing sensitivity characteristics. Assume that the waveform (i) in FIG. 7 (a) is obtained for the sensitivity characteristic (i) in FIG. 7 (b). If the sensitivity of the lever is too high, the operator will repeat the operation of tilting the lever and returning the lever if it feels too much, so that ringing will occur in the waveform (i).

  The sensitivity characteristic (ii) in FIG. 7B is obtained by performing gain correction (tilt correction) of the sensitivity characteristic (i). The correction from the sensitivity characteristics (i) to (ii) increases the speed in the region where the tilt angle θ is large and also increases the sensitivity (tilt). As a result, as shown in the waveform (ii) of FIG. 7A, the speed is increased, but the ringing is not settled.

  The sensitivity characteristic (iii) in FIG. 7B is obtained by correcting the sensitivity in addition to the gain correction (inclination correction) of the sensitivity characteristic (i). As a result of the correction from the sensitivity characteristic (i) to (iii), the speed increases in the region where the tilt angle θ is large, but the sensitivity (tilt) is small. As a result, as shown in the waveform (iii) of FIG. 7A, ringing can be suppressed while increasing the speed.

The excavator 1 can be used in various forms such as excavation, leveling work, and loading work. A sensitivity characteristic suitable for one work is not always suitable for another work. Therefore, it is desirable that the sensitivity correction unit 502 can hold a plurality of different sensitivity characteristics corresponding to a plurality of operations. Then, the sensitivity correction unit 502 generates a command value ω _REF based on the sensitivity characteristic corresponding to the work selected by the operator. This eliminates the need for the operator to bother to reset the first coordinate P1 and the second coordinate P2 each time the type of work is changed, thereby further improving work efficiency. As shown in FIG. 4, the plurality of coordinates P1 and P2 may be set by the operator for all of the plurality of sensitivity characteristics, or the sensitivity characteristics corresponding to a part of the work are fixed and the remaining work is supported. Only for the sensitivity characteristics to be performed, the operator may be able to set coordinates.

  8A to 8E are diagrams illustrating an example of sensitivity characteristics for each work mode. The upper row shows the sensitivity characteristics of the arm shaft, and the lower row shows the sensitivity characteristics of the boom shaft. Fig.9 (a) is a figure which shows the shovel 1 which performs leveling work. For efficient leveling work, it is desirable to move the arm 6 relatively large (fast) and the boom 5 relatively small (slow). Therefore, as shown in FIG. 8B, the arm shaft may be operated in a relatively large speed region, and the boom shaft may be operated in a relatively small speed region. In leveling work, since precise control is required, both the boom axis and the arm axis are set to be lower in sensitivity than the default mode in FIG.

  When a more precise work is required, the fine operation mode shown in FIG. 8C is preferable. In the fine operation mode, both the arm axis and the boom axis are set to operate with low sensitivity in a small speed range.

  FIG. 9B is a diagram illustrating an excavator that performs deep digging work. In this operation, the movable range of the boom is larger than the movable range of the arm. Therefore, it is desirable that the boom shaft can be moved faster than the arm shaft. Therefore, as shown in FIG. 8D, the arm shaft is set in a low speed range and the boom shaft is set in a high speed range.

  In simple work, accuracy is not required and high-speed operation is required. Therefore, as shown in FIG. 8E, it can be said that sensitivity characteristics that change in a high speed range for both the boom axis and the arm axis are preferable.

  FIG. 10 is a diagram showing the display means 516 when the work mode is selected. It is preferable that the work mode can be easily switched by the user interface 512 described above.

  FIG. 11 is a block diagram of an electric system and a hydraulic system of the excavator 1 according to the embodiment. In FIG. 11, the mechanical power transmission system is indicated by a double line, the hydraulic system is indicated by a thick solid line, the steering system is indicated by a broken line, and the electrical system is indicated by a thin solid line. FIG. 11 representatively shows a configuration related to the driving of the boom shaft.

  The engine 11 is connected to the main pump 14 and the pilot pump 15. A control valve 17 is connected to the main pump 14 via a high pressure hydraulic line 16. Two hydraulic circuits for supplying hydraulic pressure to the hydraulic actuator may be provided. In that case, the main pump 14 includes two hydraulic pumps. In this specification, the case where the main pump is one system will be described for easy understanding.

  The control valve 17 is a device that controls the hydraulic system in the excavator 1 and is an aggregate of a plurality of control valves. In addition to hydraulic motors (traveling hydraulic motors) 2A and 2B for driving the traveling body 2 shown in FIG. 2, a boom cylinder 7, an arm cylinder 8 and a bucket cylinder 9 are connected to the control valve 17 via a high-pressure hydraulic line. The control valve 17 controls the hydraulic pressure supplied to them according to the operation input of the operator. The control valve 17 corresponds to the driving device 504 in FIG.

  A swing hydraulic motor 13 for driving the swing mechanism 3 is connected to the control valve 17. The swing hydraulic motor 13 is connected to the control valve 17 via a hydraulic circuit of the swing control device, but the hydraulic circuit of the swing control device is not shown in FIG. 11 and is simplified.

  A pilot valve 27 is connected to the pilot pump 15 via a pilot line 18 and a switching valve 32 described later. The pilot valve 27 is connected to the operation lever 26, and the hydraulic pressure (primary hydraulic pressure) supplied through the pilot line 18 is changed to a hydraulic pressure (secondary hydraulic pressure) corresponding to the tilt angle θ of the operating lever 26. Convert and output. The operation lever 26 is an operation means for operating the traveling body 2, the turning mechanism 3, the boom 5, the arm 6, and the bucket 10, and is operated by an operator. The secondary hydraulic pressure output from the pilot valve 27 is supplied to the control valve 17 via the pilot line 28, the cushion valve 29, and a shuttle valve 38 described later.

  The above is the basic configuration of the excavator 1. Next, a configuration related to sensitivity correction according to the embodiment will be described. The excavator 1 includes a driving support system 30 in addition to the configuration described above. The driving support system 30 corresponds to the sensitivity correction unit 502 in FIG. 3 and includes a switching valve 32, a CPU 34, an electromagnetic proportional valve 36, and a shuttle valve 38. The switching valve 32 and the shuttle valve 38 are provided for switching between a control system in which sensitivity correction is invalid and a control system in which sensitivity correction is valid. Specifically, the switching valve 32 connects the pilot line 18 to the pilot line 19 when the sensitivity correction is disabled, and connects the pilot line 18 to the pilot line 20 when the sensitivity correction is enabled.

The CPU 34 corresponds to the calculation unit 510 in FIG. The CPU 34 receives an electric signal S1 indicating the tilt angle θ of the operation lever 26. For example, the tilt angle θ may be detected using a pressure sensor that detects pressure oil on the secondary side of the pilot valve 27. Alternatively, an angle sensor that directly detects the tilt angle θ may be used. The CPU 34 receives the tilt angle θ and generates a control signal S2 corresponding to the command value ω _REF corresponding to the sensitivity characteristic.

An electromagnetic proportional valve 36 is provided on the path of the pilot line 20. The electromagnetic proportional valve 36 changes the hydraulic pressure of the pilot line 21 on the output side in accordance with the control signal S2 from the CPU 34. The hydraulic pressure in the pilot line 21 corresponds to the speed command value ω _REF . The pilot line 21 is supplied to the control valve 17 via the shuttle valve 38.

  According to the shovel 1, the relationship between the tilt angle θ and the speed command of the control shaft can be corrected.

  In the above, this invention was demonstrated based on the Example. It is understood by those skilled in the art that the present invention is not limited to the above-described embodiment, and various design changes are possible, and various modifications are possible, and such modifications are within the scope of the present invention. It is a place. Hereinafter, such modifications will be described.

  In the embodiment, two coordinates of the first coordinate P1 and the second coordinate P2 can be designated, but three or more coordinates may be designated. FIG. 12 is a diagram illustrating sensitivity characteristics according to the modification. In this modification, an intermediate third coordinate P3 can be designated in addition to the first coordinate P1 and the second coordinate P2. A linear function may be used between P1 and P3 and between P3 and P2.

  Although the present invention has been described using specific terms based on the embodiments, the embodiments only illustrate the principles and applications of the present invention, and the embodiments are defined in the claims. Many variations and modifications of the arrangement are permitted without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Excavator, 2 ... Traveling body, 2A, 2B ... Traveling hydraulic motor, 3 ... Turning mechanism, 4 ... Turning body, 4a ... Driver's cab, 5 ... Boom, 6 ... Arm, 7 ... Boom cylinder, 8 ... Arm cylinder, DESCRIPTION OF SYMBOLS 9 ... Bucket cylinder, 10 ... Bucket, 11 ... Engine, 12 ... Attachment, 14 ... Main pump, 15 ... Pilot pump, 16 ... Pilot line, 17 ... Control valve, 18, 19, 20 ... Pilot line, 26 ... Operation lever , 27 ... Pilot valve, 28 ... Pilot line, 29 ... Cushion valve, 30 ... Driving support system, 32 ... Switching valve, 34 ... CPU, 36 ... Electromagnetic proportional valve, 38 ... Shuttle valve, 500 ... Control lever, 502 ... Sensitivity Correction unit, 504... Drive device, 506... Control axis, 510... Calculation unit, 511. Interface, 520 ... dead zone, 522 ... transition zone, 524 ... peak area.

Claims (5)

A traveling body,
An upper swing body that pivots relative to the traveling body;
An attachment attached to the upper swing body;
An operation lever provided at a driver's seat of the upper swing body, and tilting in a predetermined direction is associated with a motion of a control shaft that is one of a swing shaft, a boom shaft, an arm shaft, and a bucket shaft of the attachment;
A sensitivity correction unit that retains a sensitivity characteristic indicating a correspondence relationship between a tilt angle of the operation lever and a command value to the control axis that is defined in advance, and generates the command value according to the tilt angle;
A drive device for controlling the control shaft in accordance with the command value;
With
The sensitivity correcting unit generates the sensitivity characteristic so as to pass at least two coordinates input in advance by an operator.   2. The shovel according to claim 1, wherein the sensitivity correction unit has a GUI (Graphical User Interface) and receives the input of the at least two coordinates by the operator while displaying the sensitivity characteristic on a display unit. .   The said sensitivity correction | amendment part hold | maintains several different sensitivity characteristics corresponding to several operation | work, The said command value is produced | generated based on the sensitivity characteristic corresponding to the operation | work which the operator selected. 2. The excavator according to 2.   The shovel according to claim 3, wherein the sensitivity correction unit has a GUI (Graphical User Interface), displays the plurality of operations on a display unit, and accepts selection of the operations by the operator. A traveling body,
An upper swing body that pivots relative to the traveling body;
An attachment attached to the upper swing body;
An operation lever provided at a driver's seat of the upper swing body, and tilting in a predetermined direction is associated with a motion of a control shaft that is one of a swing shaft, a boom shaft, an arm shaft, and a bucket shaft of the attachment;
A plurality of sensitivity characteristics corresponding to a plurality of operations are held, and the sensitivity characteristics indicate a correspondence relationship between a tilt angle of the operation lever and a command value to the control axis, and the plurality of sensitivity characteristics are respectively A sensitivity correction unit that generates the command value according to the tilt angle based on the sensitivity characteristic that is defined to pass through at least two coordinates input in advance and corresponds to the operation selected by the operator;
A drive device for controlling the control shaft in accordance with the command value;
An excavator characterized by comprising:

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