Information display device and display control device for construction machine Number:6,826,465 from the United States Patent and Trademark Office (PTO) owispatent

Title: Information display device and display control device for construction machine

Abstract: An information display unit is provided inside a cab of a hydraulic excavator and has a display portion capable of displaying plural kinds of information including body information and maintenance information. A screen image has one main screen and a plurality of sub-screens. The main screen displays information regarding one of a plurality of information categories in detail and the plurality of sub-screens respectively correspond to th plurality of information categories. The information category displayed on the main screen can be selected and changed with key manipulation made on an operating portion. As a result, plural kinds of information can be displayed in a combined and selective manner, and an operator is able to confirm the information with higher efficiency.

Patent Number: 6,826,465 Issued on 11/30/2004 to Ishimoto,   et al.

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Inventors:	Ishimoto; Hidefumi (Tsuchiura, JP); Ogura; Hiroshi (Ryugasaki, JP); Watanabe; Hiroshi (Ushiku, JP); Adachi; Hiroyuki (Tsuchiura, JP); Sakyou; Tsuyoshi (Ibaraki-ken, JP)
Assignee:	Hitachi Construction Machinery Co., Ltd. (Tokyo, JP)
Appl. No.:	169934
Filed:	July 11, 2002
PCT Filed:	November 28, 2001
PCT NO:	PCT/JP01/10372
371 Date:	July 11, 2002
102(e) Date:	July 11, 2002
PCT PUB.NO.:	WO02/44480
PCT PUB. Date:	June 06, 2002

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Foreign Application Priority Data

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Nov 29, 2000 [JP]			2000-363745

Current U.S. Class:	701/50 ; 340/459; 701/1
Field of Search:	701/50,1,29 340/438,439,459,462

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References Cited [Referenced By]

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U.S. Patent Documents

	5854988		December 1998		Davidson et al.
	5956255		September 1999		Flamme
	6039141		March 2000		Denny
	6275231		August 2001		Obradovich
	6349252		February 2002		Imanishi et al.

Foreign Patent Documents

	5-287782		Nov., 1993		JP
	5-288648		Nov., 1993		JP
	10-103925		Apr., 1998		JP
	11-69258		Mar., 1999		JP
	11-81393		Mar., 1999		JP
	11-286971		Oct., 1999		JP

Primary Examiner: Zanelli; Michael J.
Attorney, Agent or Firm: Mattingly, Stanger & Malur, P.C.

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Claims

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What is claimed is:

1. An information display unit for a construction machine, said information display unit being provided inside a cab (6) of a construction machine (1) and having a display portion (472, 472a) capable of displaying plural kinds of information including body information and maintenance information, wherein a screen image displayed on said display portion (472, 472a) comprises one main screen (1001-1004; 3001-3004) and a plurality of sub-screens (2001-2008; 4001-4008); said main screen displays information regarding one of a plurality of information categories (A, B, C, D) in detail; said plurality of sub-screens correspond to at least the information categories other than the information category, for which information is displayed on said main screen in detail, and display information regarding the corresponding information categories in the simplified form; and input means (470) for selecting and changing the information category to be displayed on said main screen is provided, whereby with manipulation of said input means, information regarding the category displayed in one of said plurality of sub-screens is displayed on said main screen in detail and information regarding the category, which has been so far displayed on said main screen, is displayed in arbitrary one of said plurality of sub-screens in the simplified form.

2. An information display unit for a construction machine according to claim 1, wherein said main screen (1001-1004; 3001-3004) has a size occupying a substantial proportion of said display portion (472, 472a), and said plurality of sub-screens (2001-2008; 4001-4008) are smaller than said main screen.

3. An information display unit for a construction machine according to claim 1, wherein said plurality of sub-screens (2001-2008; 4001-4008) display typical information contained in the corresponding information category.

4. An information display unit for a construction machine according to claim 1, wherein at least one (B, C) of said plurality of information categories (A, B, C, D) includes combination of plural items of sub-category information belonging to the relevant information category, said main screen (1001, 1003; 3001, 3003) selectively displays at least one of said plural items of sub-category information, and the sub-category information displayed on said main screen is selected and changed with manipulation of said input means (470).

5. An information display unit for a construction machine according to claim 1, wherein a screen image displayed on said display portion (472, 472a) has a main display area (1000) and a sub-display area (2000) that are located in preset positions, said main display area displaying said main screen (1001-1004), said sub-display area (2000) displaying said plurality of sub-screens (2001-2008), and said plurality of sub-screens are disposed respectively corresponding to said plurality of information categories (A, B, C, D).

6. An information display unit for a construction machine according to claim 5, wherein one of said sub-screens (2001-2008) in said sub-display area (2000) corresponding to one of said information categories (A, B, C, D), for which information is displayed on said main screen (1001-1004) in said main display area (1000) in detail, displays symbolic illustrations (80, 81) for operation guide, which are in imitation of arrow keys and serve as aids for changing said information categories (A, B, C, D) from one to another with manipulation of said input means (470).

7. An information display unit for a construction machine according to claim 5, wherein said plurality of sub-screens (2001-2008) in said sub-display area (2000) serve as index tags for said information categories (A, B, C, D) displayed on said main screen (1001-1004) in said main display area (1000), and are designed with layout in imitation of index tags for said main display area.

8. An information display unit for a construction machine according to claim 5, wherein at least one (B, C) of said plurality of information categories (A, B, C, D) includes combination of plural items of sub-category information belonging to the relevant information category, and said main screen (1001, 1003) in said main display area (1000) selectively displays at least one of said plural items of sub-category information; and wherein the sub-category information displayed on said main screen is selected and changed with manipulation of said input means (470).

9. An information display unit for a construction machine according to claim 8, wherein when at least one of said plural items of sub-category information is displayed on said main screen (1001, 1003) in said main display area (1000), one of said sub-screens (2002, 2007) in said sub-display area (2000) corresponding to the information category, to which the displayed sub-category information belongs, displays symbolic illustrations (80, 81) for operation guide, which are in imitation of arrow keys and serve as aids for changing the information category with manipulation of said input means (470), and said one sub-screen and said main display area display symbolic illustrations (82, 85) for operation guide, which are in imitation of arrow keys and serve as aids for changing the sub-category information with manipulation of said input means.

10. An information display unit for a construction machine according to claim 1, wherein said plurality of information categories include at least meter information and abnormality warning information (D).

11. A display control unit for an information display unit (47) for a construction machine, said information display unit being provided inside a cab (6) of a construction machine (1) and having a display portion (472, 472a) capable of displaying plural kinds of information including body information and maintenance information, said display control unit comprising: processing control means (470, STEP 1004, 1005, 1006) for performing control such that a screen image displayed on said display portion (472, 472a) of said information display unit (47) comprises one main screen (1001-1004; 3001-3004) and a plurality of sub-screens (2001-2008; 4001-4008), said main screen displays information regarding one of a plurality of information categories (A, B, C, D) in detail, and said plurality of sub-screens correspond to at least the information categories other than the information category, for which information is displayed on said main screen in detail, and display information regarding the corresponding information categories in the simplified form; and changing means (470, STEP 1002, 1003) operating such that when input means (470) for selecting the information category to be displayed on said main screen is manipulated, information regarding the category displayed in one of said plurality of sub-screens is displayed on said main screen in detail and information regarding the category, which has been so far displayed on said main screen, is displayed in arbitrary one of said plurality of sub-screens in the simplified form.

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Description

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TECHNICAL FIELD

The present invention relates to an information display unit for a construction machine and a display control unit. More particularly, the present invention relates to an information display unit for a construction machine, which is provided in a cab of the construction machine and is capable of displaying plural kinds of information such as body information and maintenance information, as well as to a display control unit for the information display unit.

BACKGROUND ART

Recently, construction machines including hydraulic excavators, cranes, tunnel excavators, crushers for wood, rocks, etc., or soil amending machines for amending the contaminated soil and the soil in sterile land have been practiced in the more advanced electronic form with further improvements of performance and an increase of functions. Also, for the purpose of facilitating management of body information, increasing the work efficiency, or improving maintenance, electronic control units have been developed and mounted for each of various functions. Those electronic control units have respective devices for providing information to an operator. In other words, the functions and number of information providing devices provided in a cab have been increased. This gives rise to problems in that a burden imposed on the operator is increased with an increase in the number of items of information and more complicated manipulation, that it becomes difficult to mount necessary electronic control units within a limited space in the cab with an increase in the number of the electronic control units, and that plural types of information providing devices independent for each function must be developed and mounted, thus resulting in an increased cost. To overcome those problems, a display unit is proposed which displays plural kinds of information on one display screen in a concentrated way.

For example, JP-A 5-288648 discloses a managing and monitoring unit which has a plurality of display modes for displaying body working information, maintenance information, etc., and which is capable of changing the contents to be displayed upon switch manipulation.

Also, JP-A 5-287782 discloses a multi-function display monitoring system in which a display panel comprises a display portion and a switch portion. The monitoring system monitors excavation situations of an excavator, such as a power shovel, and displays a symbolic illustration in imitation of the excavator along with numerical information. The contents of displayed information regarding the front attitude can be changed upon switch manipulation.

Further, JP-A 10-103925 discloses an excavation control method employing an excavation information monitoring unit for an excavator, in which the contents to be displayed are changed with a touch panel.

DISCLOSURE OF INVENTION

In construction machines, for the purpose of facilitating management of body information, increasing the work efficiency, or improving maintenance, the functions and number of information providing devices provided in a cab have been increased. To cope with such a tendency, a display unit for displaying plural kinds of information on one display screen in a concentrated way is proposed, but there are several problems with techniques so far proposed for displaying information.

With the monitoring unit disclosed in JP-A 5-288648, a plurality of display modes are selectively changed depending on a vehicle status or in response to an operation instruction, and an image having the contents corresponding to the selected display mode is displayed on one screen. However, because the contents displayed on the screen are completely altered with a display mode change, the operator cannot see plural kinds of information at the same time, for example, by additionally displaying maintenance information while working information is being displayed.

Also, the monitoring units disclosed in JP-A 10-103925 and JP-A 5-287782 similarly display information of one function only, such as body information of an excavator, on one screen, and alter the displayed contents by changing an entire image on the screen.

Further, because those monitoring units are mounted in the cab as equipment independent of an ordinary instrument panel, the operator must carefully look at both the ordinary instrument panel and the monitoring unit depending on situations. This point has invited problems in viewpoints of operability and safety.

It is an object of the present invention to provide an information display unit for a construction machine and a display control unit for the information display unit, which can display plural kinds of information in a combined and selective manner and enable an operator to confirm the information with higher efficiency. (1) To achieve the above object, the present invention provides an information display unit for a construction machine, the information display unit being provided inside a cab of a construction machine and having a display portion capable of displaying plural kinds of information including body information and maintenance information, wherein a screen image displayed on the display portion comprises one main screen and a plurality of sub-screens; the main screen displays information regarding one of a plurality of information categories in detail; the plurality of sub-screens correspond to at least the information categories other than the information category, for which information is displayed on the main screen in detail, and display information regarding the corresponding information categories in the simplified form; and input means for selecting and changing the information category to be displayed on the main screen is provided, whereby with manipulation of the input means, information regarding the category displayed in one of the plurality of sub-screens is displayed on the main screen in detail and information regarding the category, which has been so far displayed on the main screen, is displayed in arbitrary one of the plurality of sub-screens in the simplified form.

Thus, by providing one main screen and a plurality of sub-screens, displaying a plurality of information categories in the detailed and simplified forms, and enabling plural items of displayed information to be changed from one to another, it is therefore possible to display plural kinds of information in a combined and selective manner, and to improve efficiency at which the operator confirms the information. (2) In above (1), preferably, the main screen has a size occupying a substantial proportion of the display portion, and the plurality of sub-screens are smaller than the main screen.

With that feature, plural kinds of information can be efficiently displayed in one screen image. (3) In above (1), preferably, the plurality of sub-screens display typical information contained in the corresponding information category.

With that feature, the information regarding the corresponding category can be displayed in the simplified form. (4) In above (1), preferably, at least one of the plurality of information categories includes combination of plural items of sub-category information belonging to the relevant information category, the main screen selectively displays at least one of the plural items of sub-category information, and the sub-category information displayed on the main screen is selected and changed with manipulation of the input means.

With those features, it is possible to increase the number of kinds of information categories that can be displayed on the main screen, and to display plural kinds of information in a combined and selective manner. (5) In above (1), preferably, a screen image displayed on the display portion has a main display area and a sub-display area that are located in preset positions, the main display area displaying the main screen, the sub-display area displaying the plurality of sub-screens, and the plurality of sub-screens are disposed respectively corresponding to the plurality of information categories.

With those features, the main screen and the sub-screens are displayed in respective constant positions so that the operator can see those screens with more ease. (6) In above (5), preferably, one of the sub-screens in the sub-display area corresponding to one of the information categories, for which information is displayed on the main screen in the main display area in detail, displays symbolic illustrations for operation guide, which are in imitation of arrow keys and serve as aids for changing the information categories from one to another with manipulation of the input means.

With that feature, the information category displayed in the main display area can be easily changed with manipulation of the input means. (7) In above (5), preferably, the plurality of sub-screens in the sub-display area serve as index tags for the information-categories displayed on the main screen in the main display area, and are designed with layout in imitation of index tags for the main display area.

With that feature, the information category displayed in the main display area can be easily selected by utilizing the sub-screens as guide tags. (8) In above (5), preferably, at least one of the plurality of information categories includes combination of plural items of sub-category information belonging to the relevant information category, the main screen in the main display area selectively displays at least one of the plural items of sub-category information, and the sub-category information displayed on the main screen is selected and changed with manipulation of the input means.

With those features, it is possible to increase the number of kinds of information categories that can be displayed in the main display area, and to display plural kinds of information in a combined and selective manner. (9) In above (8), preferably, when at least one of the plural items of sub-category information is displayed on the main screen in the main display area, one of the sub-screens in the sub-display area corresponding to the information category, to which the displayed sub-category information belongs, displays symbolic illustrations for operation guide, which are in imitation of arrow keys and serve as aids for changing the information category with manipulation of the input means, and that one sub-screen and the main display area display symbolic illustrations for operation guide, which are in imitation of arrow keys and serve as aids for changing the sub-category information with manipulation of the input means.

With those features, even with an increase in the number of kinds of information to be displayed, the information displayed in the main display area can be easily changed with manipulation of the input means. (10) In above (1), preferably, the plurality of information categories include at least meter information and abnormality warning information.

With that feature, the operator is not required to carefully look at an instrument panel separately mounted inside the cab for confirming the meter information, or the instrument panel mounted inside the cab can be itself dispensed with. Therefore, the operator is free from the necessity of carefully looking at the instrument panel and the display unit, thus resulting in an improvement of operability and safety. Further, because the abnormality warning information is displayed, maintenance is facilitated. (11) To achieve the above object, the present invention also provides a display control unit for an information display unit for a construction machine, the information display unit being provided inside a cab of a construction machine and having a display portion capable of displaying plural kinds of information including body information and maintenance information, the display control unit comprising processing control means for performing control such that a screen image displayed on the display portion of the information display unit comprises one main screen and a plurality of sub-screens, the main screen displays information regarding one of a plurality of information categories in detail, and the plurality of sub-screens correspond to at least the information categories other than the information category, for which information is displayed on the main screen in detail, and display information regarding the corresponding information categories in the simplified form; and changing means operating such that when input means for selecting the information category to be displayed on the main screen is manipulated, information regarding the category displayed in one of the plurality of sub-screens is displayed on the main screen in detail and information regarding the category, which has been so far displayed on the main screen, is displayed in arbitrary one of the plurality of sub-screens in the simplified form.

With those features, similarly to above (1), it is possible to display plural kinds of information in a combined and selective manner, and to improve efficiency at which the operator confirms the information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an electronic control system of a hydraulic excavator equipped with an information display unit according to a first embodiment of the present invention, along with the hydraulic excavator and a hydraulic system mounted therein.

FIG. 2 is a block diagram showing a configuration of the information display unit.

FIG. 3 shows, in the form of a table, details of communication data transmitted and received among control units and monitoring units via a common communication line.

FIG. 4 shows one example of a screen image displayed on the information display unit when a main screen displaying meter information is selected.

FIG. 5 shows another example of the screen image displayed on the information display unit when a main screen displaying body attitude information is selected.

FIG. 6 shows still another example of the screen image displayed on the information display unit when a main screen displaying working time information is selected.

FIG. 7 shows still another example of the screen image displayed on the information display unit when a main screen displaying abnormality warning information is selected.

FIG. 8 is a flowchart showing processing steps of a screen displaying process in the information display unit.

FIG. 9 is a flowchart showing detailed processing steps of a processing block 10010 shown in FIG. 8.

FIG. 10 is a flowchart showing detailed processing steps of a processing block 10020 shown in FIG. 8.

FIG. 11 is a flowchart showing detailed processing steps of a processing block 10030 shown in FIG. 8.

FIG. 12 is a flowchart showing detailed processing steps of a processing block 10040 shown in FIG. 8.

FIG. 13 shows an example of screen transition in the first embodiment.

FIG. 14 shows, in the form of a hierarchy, a list of screen images displayed on an information display unit according to the second embodiment.

FIG. 15 shows one example of a screen image displayed on the information display unit when a main screen displaying, as body attitude information, bucket attitude and body attitude information is selected.

FIG. 16 shows another example of the screen image displayed on the information display unit when a main screen displaying, as body attitude information, working device attitude information is selected.

FIG. 17 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, working time information is selected.

FIG. 18 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, an engine revolution speed frequency distribution is selected.

FIG. 19 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, a cooling water temperature frequency distribution is selected.

FIG. 20 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, a hydraulic fluid temperature frequency distribution is selected.

FIG. 21 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, an excavation load frequency distribution is selected.

FIG. 22 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, a pump load frequency distribution is selected.

FIG. 23 is a block diagram showing screen transition in an initial state in the information display unit.

FIG. 24 is a flowchart showing processing steps of a screen displaying process in the information display unit.

FIG. 25 is a flowchart showing detailed processing steps of a processing block 10110 shown in FIG. 24.

FIG. 26 is a flowchart showing detailed processing steps of the processing block 10110 shown in FIG. 24.

FIG. 27 is a flowchart showing detailed processing steps of the processing block 10110 shown in FIG. 24.

FIG. 28 is a flowchart showing detailed processing steps of a processing block 10120 shown in FIG. 24.

FIG. 29 is a flowchart showing detailed processing steps of a processing block 10130 shown in FIG. 24.

FIG. 30 is a flowchart showing detailed processing steps of a processing block 10140 shown in FIG. 24.

FIGS. 31A, 31B, 31C and 31D show procedures of Image Transition Example 1 in the second embodiment.

FIG. 32 shows a part of procedures of Image Transition Example 2 in the second embodiment.

FIG. 33 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 34 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 35 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 36 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 37 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 38 shows a part of the procedures of Image Transition Example 2 in the second embodiment.

FIG. 39 is a block diagram showing an electronic control system of a hydraulic excavator equipped with an information display unit according to a third embodiment of the present invention, along with the hydraulic excavator and a hydraulic system mounted therein.

FIG. 40 shows one example of a screen image displayed on an information display unit according to a fourth embodiment of the present invention when a main screen displaying body attitude information is selected.

FIG. 41 shows another example of the screen image displayed on the information display unit when a main screen displaying meter information is selected.

FIG. 42 shows still another example of the screen image displayed on the information display unit when a main screen displaying working time information is selected.

FIG. 43 shows still another example of the screen image displayed on the information display unit when a main screen displaying abnormality warning information is selected.

FIG. 44 shows a key arrangement on an operating portion of the information display unit.

FIG. 45 shows still another example of the screen image displayed on the information display unit in a state in which a cursor is moved to another sub-screen in the screen image of FIG. 40.

FIG. 46 shows still another example of the screen image displayed on the information display unit in a state in which a cursor is moved to still another sub-screen in the screen image of FIG. 40.

FIG. 47 shows still another example of the screen image displayed on the information display unit in a state in which a cursor is moved to still another sub-screen in the screen image of FIG. 40.

FIG. 48 shows still another example of the screen image displayed on the information display unit in a state in which a menu screen for a sub-screen has appeared on the screen image of FIG. 40.

FIG. 49 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as body attitude information, working device attitude information is selected upon manipulation made on the menu screen for the sub-screen in the screen image of FIG. 48.

FIG. 50 shows still another example of the screen image displayed on the information display unit in a state in which the menu screen for the sub-screen has disappeared from the screen image of FIG. 49.

FIG. 51 shows still another example of the screen image displayed on the information display unit in a state in which the menu screen for the sub-screen has appeared on the screen image of FIG. 42.

FIG. 52 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as working information, a frequency distribution table is selected upon manipulation made on the menu screen for the sub-screen in the screen image of FIG. 51.

FIG. 53 shows still another example of the screen image displayed on the information display unit in a state in which a lower menu screen has appeared on the screen image of FIG. 52 upon manipulation made on the menu screen for the sub-screen.

FIG. 54 shows still another example of the screen image displayed on the information display unit when a main screen displaying, as a frequency distribution table, a hydraulic fluid temperature distribution is selected upon manipulation made on a lower menu screen in the screen image of FIG. 53.

FIG. 55 shows still another example of the screen image displayed on the information display unit in a state in which the lower menu screen has disappeared from the screen image of FIG. 54.

FIG. 56 shows still another example of the screen image displayed on the information display unit in a state in which the menu screen for the sub-screen has disappeared from the screen image of FIG. 55.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment

A first embodiment of the present invention will be first described with reference to FIGS. 1 to 13.

Mechanism of Hydraulic Excavator.cndot.Hydraulic System.cndot.Electronic System.cndot.Operation

FIG. 1 is a block diagram showing an electronic control system of a hydraulic excavator equipped with an information display unit according to a first embodiment of the present invention, along with the hydraulic excavator and a hydraulic system mounted therein.

Referring to FIG. 1, a hydraulic excavator 1 comprises a track body 2, a swing body 3, an excavation working device (front working mechanism) 7. The excavation working device 7 is made up of a boom 8 vertically pivotably mounted to the swing body 3, an arm 9 rotatably mounted to a fore end of the boom 8, a bucket 10 rotatably mounted to a fore end of the arm 9, a boom operating hydraulic cylinder 11 for vertically pivoting the boom 8, an arm operating cylinder 12 for rotating the arm 9, and a bucket operating hydraulic cylinder 13 for rotating the bucket 10.

The swing body 3 has an accommodating room 4 for accommodating an engine 14 and hydraulic equipment such as a hydraulic pump 18. A cab 6 is provided on the front left side of the swing body 3.

The engine 14 is provided with an electronic governor 15 for maintaining the revolution speed of the engine 14 within a certain range. A target revolution speed Nr of the engine 14 set by a target revolution speed setting unit 16.

The hydraulic pump 18 is driven for rotation by the engine 14. Also, the hydraulic pump 18 is a variable displacement pump and is provided with a swash plate 19 for varying a pump delivery rate. A delivery rate adjusting device 20 is coupled to the swash plate 19. Further, there are provided a swash plate position sensor 21 for detecting a tilting position .theta. of the swash plate 19, and a pressure sensor 22 for detecting a delivery pressure Pd of the hydraulic pump 18.

The boom operating hydraulic cylinder 11, the arm operating cylinder 12, and the bucket operating hydraulic cylinder 13 are connected to the hydraulic pump 18 through control valves 24, 25, 26, respectively. Flow rates and directions of hydraulic fluids supplied from the hydraulic pump 18 to the respective cylinders 11, 12, 13 are adjusted by the control valves 24, 25, 26. Control levers 27, 28, 29 are provided in association with the control valves 24, 25, 26, and lever operating units 30, 31, 32 are coupled to the control levers 27, 28, 29, respectively. The lever operating units 30, 31, 32 output, as operating signals X1, X2, X3 for the control levers 27, 28, 29, electrical signals depending on shift amounts by which the respective control levers are operated.

The excavation working device 7 is provided with a boom rotational angle sensor 35 for detecting a rotational angle .alpha. of the boom 8, an arm rotational angle sensor 36 for detecting a rotational angle .beta. of the arm 9, and a bucket rotational angle sensor 38 for detecting a rotational angle .gamma. of the bucket 10.

Further, a first control unit 17, a second control unit 23, a third control unit 33 and a fourth control unit 37 are provided for controlling various components of the hydraulic excavator, and a first monitoring unit 45, a second monitoring unit 46 and an information display unit 47 are provided for giving an operator information regarding the inside and outside of a machine body. The first to fourth control units 17, 23, 33, 37, the first and second monitoring unit units 45, 46, and the information display unit 47 are interconnected via a communication line 46 for transmitting and receiving data among them.

The first control unit 17 controls the engine 14. More specifically, the first control unit 17 receives the target revolution speed Nr from the target revolution speed setting unit 16 and an actual revolution speed Ne detected by the governor 15, and then executes predetermined computations, thereby outputting a control signal R to the governor 15. As a result, the engine 14 is controlled such that the actual revolution speed Ne matches with the target revolution speed Nr from the target revolution speed setting unit 16.

The second control unit 23 controls the hydraulic pump 18. More specifically, the second control unit 23 receives the delivery pressure Pd of the hydraulic pump 18 detected by the pressure sensor 22, the tilting position .theta. of the swash plate 19 detected by the swash plate position sensor 21, and the operating signals X1 to X7 from the third control unit 33, and then executes predetermined computations, thereby outputting a control signal for the swash plate 19 to the delivery rate adjusting device 20 for the hydraulic pump 18. As a result, the delivery rate of the hydraulic pump 18 is adjusted with the operation of the delivery rate adjusting device 20.

The third control unit 33 controls the control valves 24, 25, 26. More specifically, the third control unit 33 receives electrical signals from the lever operating units 30, 31, 32 and then executes predetermined computations, thereby outputting control signals to operating sectors 24L, 24R, 25L, 25R, 26L, 26R of the control valves 24, 25, 26. As a result, respective shift positions of the control valves 24, 25, 26 are controlled in accordance with the operating signals X1, X2, X3 from the control levers 27, 28, 29, whereby the flow rates and flowing directions of the hydraulic fluids supplied to the cylinders 11, 12, 13 are controlled.

Further, through not shown, there are provided a swing control lever unit, a track control lever unit, and an attachment control lever unit. The third control unit 33 receives, from those control lever units, a swing operating signal X4, left and right track operating signals X5, X6, and an operating signal X7 for an attachment separate from the bucket 10 that is equipped as a standard option, and then executes predetermined computations, thereby outputting control signals to control valves (not shown). As a result, the flow rates and flowing directions of the hydraulic fluids supplied to respective actuators (not shown) are controlled.

The fourth control unit 37 controls the excavation working device 7. More specifically, the fourth control unit 37 receives respective signals for the rotational angles .alpha., .beta., .gamma. from the rotational angle sensors 35, 36, 38 and the operating signals X1, X2, X3 of the control lever units 27, 28, 29 from the third control unit 33, and then executes predetermined computations, thereby modifying the operating signals X1, X2, X3 and outputting control driving commands Y.alpha., Y.beta., Y.gamma. to the third control unit 33. As a result, the control valves 24, 25, 26 are controlled so as to control, for example, the locus of the excavation working device 7 in its operation.

Further, the engine 14 is provided with a hydraulic pressure sensor 41 for measuring a pressure Poil of a lubricant (engine oil), and a radiator 51 for cooling engine cooling water is provided with a water temperature sensor 42 for detecting a cooling water temperature Tw. Respective signals of the engine oil pressure Poil and the cooling water temperature Tw detected by the sensors 41, 42 are inputted to the first control unit 17.

In addition, as sensors for monitoring other various states in the body of the hydraulic excavator 1, there are provided a fuel level sensor 43 for measuring a fuel level (amount of fuel remaining) Fuel, a pressure sensor 44 for detecting a filter pressure Pflt of a filter 50 provided in a hydraulic system circuit to detect clogging of the filter 50, a hydraulic fluid temperature sensor for detecting a temperature T.sub.0 of the hydraulic fluid in the hydraulic system, and a tilt sensor 49 for detecting a body tilt angle .xi.. Respective signals of the fuel level Fuel and the filter pressure Pflt, detected by the sensors 43, 44 are inputted to the first monitoring unit 45. A signal of the hydraulic fluid temperature T.sub.0 detected by the sensor is inputted to the second control unit 23, and a signal of the body tilt angle .xi. detected by the tilt sensor 49 is inputted to the fourth control unit 37.

The first monitoring unit 45 transmits information of the fuel level Fuel and the filter pressure Pflt, which are detected respectively by the sensors 43, 44, to the information display unit 47. When an instrument panel is provided in the cab 6, those items of information are displayed on the instrument panel.

The second monitoring unit 46 receives detection data (described later) from the first control unit 17, the second control unit 23 and the first monitoring unit 45 via the communication line 40, and then processes those data for time-serially or statistically measuring and the storing abnormality detection history, the machine working time, the working status, etc. Further, the second monitoring unit 46 transmits those items of information to the information display unit 47.

The information display unit 47 receives various kinds of information (described later) from the first to fourth control units 17, 23, 33, 37 and the first and second monitoring units 45, 46 via the communication line 40, and then displays the received information. Also, the information display unit 47 has the function of instructing, e.g., a target locus in works of the excavation working device 7 to the fourth control unit 37.

Information Display Unit

FIG. 2 shows a configuration of the information display unit 47. The information display unit 47 comprises an operating portion 470 serving as input means, a display control portion 471, and a display portion 472 having a screen 472a, such as an LCD.

The operating portion 470 includes various switches such as upward and downward arrow keys 470a, 470b and leftward and rightward arrow keys 470c, 470d which are depressed, for example, when the operator wants to change a display image, numerical value increment and decrement entry keys 470e, 470f which are depressed, for example, when the operator enters a target value for control, and a mode switch (not shown).

The display control portion 471 comprises an interface 471a for receiving signals from the operating portion 470, a central processing unit (CPU) 471b, a read only memory (ROM) 471c for storing programs for control procedures and constants necessary for control, a random access memory (RAM) 471d for temporarily storing numerical values given as computed results or obtained in the course of computation, an output interface (I/F) 471e, and a communication controller 471f for controlling communication with the first to fourth control units 17, 23, 33, 37 and the first and second monitoring unit units 45, 46 which are all connected to the common communication line 40.

The information display unit 47 is disposed inside the cab 6. The operating portion 470, the display control portion 471, and the display portion 472 of the information display unit 47 are preferably constructed as separate units, and the display portion 472 is attached to such a position inside the cab 6 as allowing the operator to see it with ease, e.g., at a corner of the cab on the obliquely right-hand side looking from an operator's seat.

FIG. 3 shows, in the form of a table, details of communication data transmitted and received among the control units and the monitoring units via th common communication line 40. In FIG. 3, "ID No." represents an ID number assigned to individual data. A mark .largecircle. represents data transmitted from the control unit or the monitoring unit. A mark .circle-solid. represents data received by the control unit or the monitoring unit. "Communication Cycle" represents an interval at which the control unit transmitting data transmits that data, i.e., a time interval at which data is update . In the "Cycle" column, "upon display manipulation" indicates that a signal is transmitted from the information display unit 47 only when an instruction button (not shown) provided in the operating portion 470 of the information display unit 47 is manipulated.

Also, the second monitoring unit 46 receives data of the actual engine revolution speed Ne, the engine oil pressure Poil and the cooling water temperature Tw from the first control unit 17, data of the pump delivery pressure Pd, the pump tilting angle .theta. and the hydraulic fluid temperature T.sub.0 from the second control unit 23, the arm operating signal X2, the swing operating signal X4, the left and right track operating signal X5, X6 and the attachment operating signal X7 from the third control unit 33, and data of the fuel level Fuel and the filter pressure Pflt from the first monitoring unit 45. Using those data, the second monitoring unit 46 prepares various data, i.e., abnormality detection history HisW, working time (key-on) TmwKey, working time (engine-on) TmwEng, working time (excavation) TmwExc, working time (travel) TmwRun, working time (swing) TmwRot, working time (ML) TmwML, working time (ATT) TmwATT engine revolution speed frequency distribution HistEng, cooling water temperature frequency distribution HistTw, hydraulic fluid temperature frequency distribution HistT.sub.0, pump load frequency distribution HistPld, and excavation load frequency distribution HistEld. Those data are transmitted to the information display unit 47 along with information of time-of-day Time based on RTC (clock function) built in the second monitoring unit 46.

The data of the abnormality detection history HisW is prepared from data of the engine oil pressure Poil, the cooling water temperature Tw, the pump delivery pressure Pd, etc. The working time (key-on) TmwKey is calculated as a power-on time in the second monitoring unit 46. The working time (engine-on) TmwEng is calculated as an on-time of the engine revolution speed Ne. The working time (excavation) TmwExc is calculated as an on-time of the arm operating signal X2. The working time (travel) TmwRun is calculated as an on-time of the left and right track operating signals X5, X6. The working time (swing) TmwRot is calculated as an on-time of the swing operating signal X4. The working time (ML) TmwML is calculated as an on-time of a signal from an ML mode switch (not shown). The working time (ATT) TmwATT is calculated as an on-time of the attachment operating signal X7.

Further, the engine revolution speed frequency distribution HistEng is prepared by processing data of the engine revolution speed Ne so as to obtain a frequency distribution thereof. The cooling water temperature frequency distribution HistTw is prepared by processing data of the cooling water temperature Tw so as to obtain a frequency distribution thereof. The hydraulic fluid temperature frequency distribution HistT.sub.0 is prepared by processing data of the hydraulic fluid temperature T.sub.0 so as to obtain a frequency distribution thereof. The pump load frequency distribution HistPld is prepared by processing data of the pump delivery pressure Pd so as to obtain a frequency distribution thereof. The excavation load frequency distribution HistEld is prepared by processing data of the pump delivery pressure Pd, which is obtained when the arm operating signal X2 is turned on, so as to obtain frequency distribution thereof.

The information display unit 47 receives the data of the actual engine revolution speed Ne, th engine oil pressure Poil and the cooling water temperature Tw from the first control unit 17, the data of the hydraulic fluid temperature T.sub.0 from the second control unit 23, the data of the control driving commands Y.alpha., Y.beta., Y.gamma., the rotational angles .alpha., .beta., .gamma. of the boom, the arm and the bucket, a depth (height) hx of the bucket fore end and a reach by of the bucket fore end from the fourth control unit 37, the data of the fuel level Fuel and the filter pressure Pflt from the first monitoring unit 45, and the above-mentioned various data from the second monitoring unit 46. Then, the information display unit 47 displays the received data while changing and combining them properly.

Examples of Displayed Screen Images

Display of images on the display portion 472 (FIG. 2) of the information display unit 47 will be described with reference to FIGS. 4 to 7.

In FIGS. 4 to 7, a screen image displayed on the screen 472a of the display portion 472 (hereinafter referred to as a displayed screen image) displays information regarding plural kinds of information categories at the same time. On that occasion, information of one category among the plural kinds of information categories is displayed in detail, and information of the other categories is displayed in the simplified form. Which one of the information categories is to be displayed in detail can be changed in turn upon key manipulation made on the operating portion 470 (FIG. 2) by the operator.

The displayed screen image has a main display area 1000 and a sub-display area 2000 that are located in preset positions. The main display area 1000 represents an area for detailed display, whereas the sub-display area 2000 represents an area for simplified display.

In FIG. 4, the main display area 1000 displays one main screen 1002, and the sub-display area 2000 displays sub-screens 2005, 2006, 2003, 2004 in the same number as the number of the information categories. The sub-screens correspond to the information categories in a one-to-one relation.

Similarly, in FIG. 5, the main display area 1000 displays one main screen 1001, and the sub-display area 2000 displays sub-screens 2001 to 2004 in the same number as the number of the information categories. In FIG. 6, the main display area 1000 displays one main screen 1003, and the sub-display area 2000 displays sub-screens 2001, 2006, 2007, 2004 in the same number as the number of the information categories. In FIG. 7, the main display area 1000 displays one main screen 1004, and the sub-display area 2000 displays sub-screens 2001, 2006, 2003, 2008 in the same number as the number of the information categories. The sub-screens correspond to the information categories in a one-to-one relation.

Each of the main screens 1001 to 1004 displays the information regarding the corresponding information category in detail.

Each sub-screen 2002, 2005, 2007, 2008 corresponding to the information category, for which information is displayed in corresponding one of the main screens 1001 to 1004 in detail, display the name of the information category and symbolic illustrations 80, 81 for operation guide to the operator. The symbolic illustrations 80, 81 for operation guide serve as aids for the operator to change the information category with key manipulation made on the operating portion 470, and are designed in imitation of the upward and downward arrow keys 470a, 470b (FIG. 2) on the operating portion 470. The other sub-screens 2006, 2003, 2004 (FIG. 4), 2001, 2003, 2004 (FIG. 5), 2001, 2006, 2004 (FIG. 6), and 2001, 2006, 2003 (FIG. 7) display information that belongs to the corresponding information categories in the simplified form. The simplified display is performed, for example, by displaying information regarding a typical one of the corresponding information categories.

The sub-screens 2005, 2006, 2003, 2004 (FIG. 4), 2001 to 2004 (FIG. 5), 2001, 2006, 2007, 2004 (FIG. 6), and 2001, 2006, 2003, 2008 (FIG. 7) are each arranged so as to serve also as an index (guide) tag for the corresponding information category, and are designed with layout so as to provide index tags for the main display area 1000.

The manipulation made by the operator for changing the information category to be displayed in the main display area 1000 and change of the screen image will be described in connection with, e.g., the case of changing one example of the displayed screen image shown in FIG. 5 to another shown in FIG. 4.

When the operator wants to change the information category displayed in the main display area 1000, the information category to be displayed in the main display area 1000 in detail can be changed by newly selecting the sub-screen 2001 corresponding to the desired information category instead of the sub-screen 2002 corresponding to the currently selected information category. That selection can be made by manipulating the upward arrow keys 470a (FIG. 2) with the aid of the symbolic illustration 80 for operation guide (as described later). Upon that manipulation, the information, which has been so far displayed in the sub-screen 2001 corresponding to the newly selected information category in the simplified form, is shifted to the main screen 1002 and is displayed in detail. In the sub-screen 2005, the name of the selected information category and the symbolic illustration 80 for operation guide are displayed instead. Also, the detailed information on the main screen 1001 corresponding to the information category, which has been so far selected, is shifted to be display on the sub-screen 2006 in the simplified form after change of the screen image.

Next, examples of the screen image displayed on the display portion 472 will be described.

In this embodiment, four kinds of information shown in FIGS. 4 to 7, i.e., meter information, body attitude information, working information, and abnormality warning information, are set as the information categories. A description is made of the contents of the displayed screen image in the state in which those information categories are selected one by one.

Category A

In FIG. 4, the main screen 1002 of the displayed screen image is a screen corresponding to an instrument panel, and displays an engine revolution speed 1200, a cooling water temperature 1201, a hydraulic fluid temperature 1202, and a fuel level 1203 using numerical values, a circle type meter and a bar type meter. The sub-screen 2005 displays the name of the selected information category and the symbolic illustration 80 for operation guide to the operator. The sub-screens 2006, 2003, 2004 correspond to the body attitude information, the working information and the abnormality warning information, respectively, and display the information (typical items) regarding the respective information categories in the simplified form. The sub-screen 2006 displays the attitude and fore end position of the bucket using numerical values and a symbolic illustration. The sub-screen 2003 displays the engine-on time and the accumulated excavation time using numerical values. The sub-screen 2004 displays an abnormality item in the event of an abnormality.

Category B

In FIG. 5, the main screen 1001 of the displayed screen image is a screen displaying the bucket attitude and the body attitude, and displays a body transverse tilt angle 1100, a bucket rotational angle 1101 and a bucket height 1102 using numerical values and a symbolic illustration in imitation of an entire image or each component of the actual machine. The sub-screen 2002 displays the name of the selected information category and the symbolic illustrations 80, 81 for operation guide to the operator. The sub-screens 2001, 2003, 2004 correspond to the meter information, the working information and the abnormality warning information, respectively, and display the information (typical items) regarding the respective information categories in the simplified form. The sub-screen 2001 displays the cooling water temperature, the hydraulic fluid temperature and the fuel level using needle type meters. The sub-screens 2003, 2004 display the same contents as those described above. That point is similarly applied to the following categories.

Category C

In FIG. 6, the main screen 1003 of the displayed screen image is a screen displaying information of the working time, and displays a key-on time 1300, an engine-on time 1301, an excavation time 1302, a travel time 1303, a swing time 1304, an ML crane operating time 1305 and an attachment operating time 1306 using numerical values and bar type meters. The sub-screen 2007 displays the name of the selected information category and the symbolic illustrations 80, 81 for operation guide to the operator. The sub-screens 2001, 2006, 2004 correspond to the meter information, the body attitude information and the abnormality warning information, respectively, and display the information (typical items) regarding the respective information categories in the simplified form.

Category D

In FIG. 7, the main screen 1004 of the displayed screen image is a screen displaying abnormality warning, and displays abnormality occurrence history and failure occurrence history along with the date/time of occurrence of each abnormality or failure. The sub-screen 2008 displays the name of the selected information category and the symbolic illustration 81 for operation guide to the operator. The sub-screens 2001, 2006, 2003 correspond to the meter information, the body attitude information and the working information, respectively, and display the information (typical items) regarding the respective information categories in the simplified form.

Description of Screen Displaying Process

Details of processing executed in the display control portion 471 (FIG. 2) of the information display unit 47 for providing the above-mentioned display of the screen images will be described using a display status flag. It is assumed that any of the information category names A, B, C, D is set to the display status flag. The processing flow is shown in FIG. 8.

(1) STEP 10001: First, upon start-up of the information display unit 47, the display status flag indicating which one of the information categories is selected at present is set to A, i.e., meter information. In other words, the initial state is set to the category A.

(2) STEP 10002: It is then determined whether any of the upward and downward arrow keys 470a, 470b (FIG. 2) on the operating portion 470 of the information display unit 47 is depressed. If depressed, the processing flow goes to STEP 10003, and if not depressed, the processing flow goes to STEP 10004.

(3) STEP 10003: This step executes a processing block 10010 for changing the display status flag depending on the arrow key depressed.

(4) STEP 10004: This step executes a processing block 10020 for carrying out a main screen displaying process.

(5) STEP 10005: This step executes a block 10030 for carrying out a sub-screen displaying process 1 (displaying process for the sub-screen corresponding to the information category selected by the display status flag).

(6) STEP 10006: This step executes a block 10040 for carrying out a sub-screen displaying process 2 (displaying process for the sub-screen corresponding to the information category not selected by the display status flag).

(7) STEP 10007: The processing flow returns to STEP 10002 for repeating the subsequent steps.

Description of Processing Block 10010

This block 10010 executes processing to change the display status flag depending on the arrow key depressed. The processing flow is shown in FIG. 9.

(1) STEP 10011: It is determine which one of the upward arrow key 470a (hereinafter indicated by ".uparw." for brevity) and the downward arrow key 470b (hereinafter indicated by ".dwnarw." for brevity) is depressed. If ".uparw." is depressed, the processing flow goes to STEP 10012a, and if ".dwnarw." is depressed, the processing flow goes to STEP 10012b.

(2) STEP 10012a: If the display status flag is set to A, nothing is changed and the current state is maintained. If the display status flag is set to B, C or D, it is changed to A, B, C, respectively. Then, the processing flow goes to STEP 10013.

(3) STEP 10012b: If the display status flag is set to D, nothing is changed and the current state is maintained. If the display status flag is set to A, B or C, it is changed to B, C, D, respectively. Then, the processing flow goe