Excavation teaching apparatus for construction machine

1. An excavation teaching device for a construction machine for carrying out excavation to shape a three-dimensional landform into a three-dimensional target landform having a specific grade with operation of an operating mechanism for excavation,

said excavation teaching device comprising position measuring means for measuring a three-dimensional position of an operating mechanism of said construction machine, and

display means for displaying a positional relationship between the three-dimensional target landform and said operating mechanism in accordance with a measured result of said position measuring means,

wherein said display means displays, as an image in a first screen area, a plurality of small plane surfaces constituting the three-dimensional target landform and an illustration of the whole or a part of said construction machine including a body of said construction machine and at least a fore end portion of said operating mechanism, and said excavation teaching device automatically selects and said display means discriminatively displays in said first screen area, as a target excavation surface, one of the plurality of small plane surfaces constituting the three-dimensional target landform, which satisfies that the direction normal to the one small plane surface is parallel within a range of allowable error, to a vertical plane in which said operating mechanism operates whereby the target landform is excavated to the specific grade.

2. An excavation teaching device for a construction machine according to claim 1 ,

wherein said display means displays, as an image in a second screen area representing a cross-sectional view taken along a plane in which said operating mechanism operates, an intersect line between the plane in which said operating mechanism operates and the plurality of small plane surfaces, and the illustration of the whole or a part of said construction machine concurrently with the image in said first screen area.

3. An excavation teaching device for a construction machine according to claim 1 ,

wherein when there are a plurality of target excavation surfaces, said display means discriminately displays one of the target excavation surfaces which is nearest to said operating mechanism.

4. An excavation teaching device for a construction machine according to claim 1 ,

wherein when there are a plurality of target excavation surfaces, said display means displays the target excavation surfaces in different color tones such that the order in distance from the direction normal to each target excavation surface to the plane in which said operating mechanism operates is represented from the nearest to farthest target excavation surface.

5. An excavation teaching device for a construction machine according to claim 1 ,

further comprising switching means for switching-over from an automatic setting mode to a manual setting mode in selection of the target excavation surface,

wherein when the manual setting mode is selected by said switching means, said display means discriminatively displays the small plane surface selected by an operator.

6. An excavation teaching device for a construction machine according to claim 1 ,

wherein said display means discriminatively displays one or more of the plurality of small plane surfaces constituting the three-dimensional target landform which are positioned within a predetermined distance from said construction machine.

7. An excavation teaching device for a construction machine according to claim 1 ,

wherein when none of the plurality of small plane surfaces constituting the three-dimensional target landform satisfies that the direction normal to each small plane surface is parallel within the range of allowable error to the plane in which said operating mechanism operates, said display means displays a message indicating the absence of the relevant small plane surfaces.

8. An excavation teaching device for a construction machine according to claim 1 ,

wherein said display means further displays, in said first screen area, a line resulting from projecting a line normal to the target excavation surface, selected from among the plurality of small plane surfaces constituting the three-dimensional target landform, on a horizontal plane and the direction in which the operating mechanism of said construction machine operates with current orientation thereof.

9. An excavation teaching device for a construction machine according to claim 8 ,

wherein said display means concurrently displays, in said first screen area, a center position of the body of said construction machine.

10. An excavation teaching device for a construction machine according to claim 8 ,

wherein said display means displays, as an image in a second screen area representing a cross-sectional view taken along a plane in which said operating mechanism operates, an intersect line between the plane in which said operating mechanism operates and the plurality of small plane surfaces, and the illustration of the whole or a part of said construction machine concurrently with the image in said first screen area.

11. An excavation teaching device for a construction machine according to claim 8 ,

wherein said display means concurrently displays, in said first screen area, a line representing the direction in which a travel body of said construction machine is moved.

12. An excavation teaching device for a construction machine for carrying out excavation to shape a three-dimensional landform into a three-dimensional target landform having a specific grade with operation of an operating mechanism for excavation,

said excavation teaching device comprising position measuring means for measuring a three-dimensional position of an operating mechanism of said construction machine, and

display means for displaying a positional relationship between the three- dimensional target landform and said operating mechanism in accordance with a measured result of said position measuring means,

wherein said display means displays, as an image in a first screen area, a plurality of small plane surfaces constituting the three-dimensional target landform and an illustration of the whole or a part of said construction machine including at least a fore end portion of said operating mechanism, and further displays, in said first screen area, a line resulting from projecting a line normal to a target excavation surface, selected from among the plurality of small plane surfaces constituting the three-dimensional target landform, on a horizontal plane and the direction in a vertical plane in which the operating mechanism of said construction machine operates with current orientation thereof, whereby the target landform is excavated to the specific grade.

13. An excavation teaching device for a construction machine according to claim 12 ,

wherein said display means concurrently displays, in said first screen area, a center position of a body of said construction machine.

14. An excavation teaching device for a construction machine according to claim 12 ,

wherein said display means displays, as an image in a second screen area representing a cross-sectional view taken along a plane in which said operating mechanism operates, an intersect line between the plane in which said operating mechanism operates and the plurality of small plane surfaces, and the illustration of the whole or a part of said construction machine concurrently with the image in said first screen area.

15. An excavation teaching device for a construction machine according to claim 12 ,

wherein said display means concurrently displays, in said first screen area, a line representing the direction in which a travel body of said construction machine is moved.