JP3537094B2 - Excavating apparatus, driving method thereof, and inclination angle measuring apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digging device used in a digging process such as construction work and civil engineering work, a driving method thereof, and a tilt angle measuring device which can be mounted on the digging device. It is suitable to be applied to a power shovel, a wheel loader, a rotary car for snow removal, and the like used in.

[0002]

2. Description of the Related Art Conventionally, a hydraulic power shovel has been used in a process of excavating the ground or earth and sand at a construction site of construction work or civil engineering work. In the conventional actual on-site work, since the inclination angle (gradient) of the final excavation surface is specified by the design document, a gradient detector is directly applied to the excavation surface, and after detecting the inclination angle with respect to the horizontal plane, the target is set as the target. Over excavation was prevented by repeating a series of operations of excavating with a power shovel to approach the inclination angle. In such a method in which the gradient detector is directly applied to the excavation surface, the operator must proceed with excavation very carefully at the final stage of excavation, so that the operation efficiency cannot be improved.

[0003] In order to improve the efficiency of excavation work,
Recently, a device has been developed that measures the inclination angle of the bottom surface of a power shovel bucket (a box-shaped member with claws for directly excavating earth and sand). FIG. 8 shows a first conventional technique for measuring the inclination angle of the bottom surface of a bucket. In FIG. 8, a boom 13 is provided on a main body of a power shovel (not shown) so as to be tiltable, and the boom 13 is rotatable. Arm 14
The bucket 15 is rotatably attached to the tip of the arm 14, and the gradient detector 5 is integrally fixed to the bucket 15, and the inclination angle of the bottom surface of the bucket 15 with respect to the horizontal plane is fixed by the gradient detector 5. Directly detected. In this case, assuming that the trench 3 whose bottom surface 3a is substantially horizontal is excavated on the ground to be constructed by the power shovel, in the final stage of excavation, the inclination detector 5 detects the inclination angle of the bucket 15, and The operator has operated the power shovel so as to move the bucket 15 in a direction (direction of arrow C) where the detection result becomes 0 within a predetermined allowable range.

As a second conventional technique for measuring the inclination angle of the bottom surface of a bucket, a boom of a power shovel,
Measure the drive angle of the arm and bucket 3
A control system has also been developed in which a plurality of sensors are combined with an inclination sensor for measuring the inclination angle of the power shovel main body, and the inclination angle of the bucket is calculated from the measured values of the four sensors. In this control system, a sensor was not directly attached to the bucket, but a sensor for measuring a rotation angle from a winding amount of a wire was used as a sensor for measuring a drive angle of the boom, the arm, and the bucket.

[0005]

As described above, techniques for directly or indirectly measuring the inclination angle of the bottom surface of a bucket have been developed in order to enhance the work efficiency of the power shovel. However, in the first prior art, as shown in FIG. 8, since the gradient detector 5 is directly mounted on the bucket 15, the vibration of the bucket is easily transmitted directly to the gradient detector 5, and a complete waterproof structure is required. Since it is difficult to employ the gradient detector, there is an inconvenience that the gradient detector 5 easily breaks down.
Further, it is necessary to extend a signal cable between the bucket 15 and the arm 14, but there is a possibility that the signal cable is disconnected due to a strong vibration of the bucket 15.

In addition, in a power shovel, there is a case where it is desired to replace a bucket according to an object to be excavated. However, when a slope detector is provided in the bucket itself, there is also a disadvantage that it is difficult to replace the bucket. On the other hand, in the second prior art, since four sensors are used, there is a disadvantage that assembling adjustment takes time and the manufacturing cost increases.
In addition, since many sensors are used, there is an inconvenience that maintenance is complicated.

SUMMARY OF THE INVENTION In view of the foregoing, the present invention does not directly attach a tilt angle sensor to a bucket of an excavator such as a power shovel, and accurately measures the tilt of the bucket with a small number of sensors. Another object is to provide a controllable technique. Further, the present invention also provides a technique in which even when the bucket portion of such an excavator is replaced, the inclination angle of the bucket portion after the replacement can be easily measured or controlled accurately with a small number of sensors. Aim.

[0008]

According to the driving method of an excavator according to the present invention, a link mechanism (2) is connected to an arm (14).
4) A bucket section (15) rotatably provided via
In the driving method of the excavating apparatus for excavating the surface to be machined by using the first tilt sensor (51) attached to the arm portion, the arm portion and the bucket portion of the link mechanism are integrally formed with each other. A second inclination sensor (52) is attached to a portion (25) that does not displace
And calculating the tilt angle of the bucket portion based on the measurement information of the second tilt sensor, and controlling the tilt angle of the bucket portion based on the calculation result.

According to the present invention, the first and second
Are sensors for detecting a tilt angle (rotation angle) of a measurement target portion with respect to a predetermined reference plane (for example, a horizontal plane) or a predetermined reference member. Since the link mechanism is interlocked with the bucket section, information on the inclination angle of the arm section (measurement information of the first inclination sensor) and information on the inclination angle of a part of the link mechanism (second inclination information) Sensor measurement information), it is possible to accurately calculate, for example, the inclination angle of the bottom of the bucket of the excavator (eg, power shovel, wheel loader, etc.), and based on the calculation result, The tilt angle can be accurately controlled.

The bucket portion of the present invention has a box-shaped member mounted on a power shovel or the like and having an open end for directly excavating earth and sand, as well as shaving (scraping) earth and sand and snow. ) Is also included. In the present invention, the first and second inclination sensors (51, 52) each measure an inclination angle of a measurement target portion with respect to a horizontal plane, and based on the measurement information and the shape information of the link mechanism (24). It is desirable to calculate the inclination angle of the bucket with respect to the horizontal plane.

From the shape information of the link mechanism (lengths of a plurality of members constituting the link, etc.) and the measurement information based on the horizontal plane of the tilt sensors, the tilt angle of the bucket portion with respect to the horizontal plane is accurately calculated. can do. In ordinary construction work and civil engineering work, it is necessary to finally process the inclination angle of a digging surface by a digging device such as a power shovel to a design value (target value) with reference to a horizontal plane. Therefore, according to the present invention, it is possible to easily control the angle of inclination of the bucket portion to an angle required in normal construction only by using two inclination sensors.

As an example, the bucket portion (1)
Based on the calculation result of the inclination angle of 5), the bucket part may be moved with respect to the surface to be processed in a state where the bucket part is set within a target inclination angle range.
This makes it possible to easily set the inclination angle of the processed surface (excavated surface) to the design value in the final stage of excavation.
Next, the excavator according to the present invention is provided with a predetermined support member (1).
Arm part (14) provided rotatably with respect to 3)
And a bucket portion (15) rotatably provided to the arm portion via a link mechanism (24), wherein the bucket portion is connected to the arm portion via the link mechanism. Driving unit (21) that rotates and drives
And a first inclination sensor (5
1) and a portion of the link mechanism where the arm and the bucket are not integrally displaced (25)
And a calculation unit (53) for calculating the tilt angle of the bucket unit based on the measurement information of the first and second tilt sensors.

According to the present invention, since the link mechanism is interlocked with the bucket, information on the inclination angle of the arm (measurement information of the first tilt sensor) and a part of the link mechanism are used. Using the information on the tilt angle (measurement information of the second tilt sensor), the tilt angle of, for example, the bottom surface of the bucket can be accurately calculated, and the tilt angle of the bucket can be calculated based on the calculation result. Can be precisely controlled.

In this case, as an example, the first and second
The inclination sensor of each measures the inclination angle of the measurement target part with respect to the horizontal plane, and the link mechanism thereof uses the arm part (1).
4) a first member (14a) having a tip portion, a second member (30) provided integrally with the bucket portion, and a third member connecting the tip portion of the driving portion and the bucket portion. (28) and a fourth member (25) connecting one end of the first member and one end of the third member to each other via parallel rotatable fulcrums (23, 26, 27, 29). The second tilt sensor measures the tilt angle of the fourth member (25) of the link mechanism,
The calculation unit calculates an inclination angle of the bucket with respect to the horizontal plane based on the measurement information and the shape information of the link mechanism.

When the link mechanism has a parallelogram shape, the relationship between the inclination angle of the fourth member of the link mechanism and the inclination angle of the bucket is simplified.
The inclination angle of the bucket can be easily calculated. In addition, by calculating the inclination angle of the bucket portion with respect to the horizontal plane, it is possible to improve the work efficiency in normal construction.

In this regard, the link mechanism may be a perfect parallelogram. In this case, the measurement value of the second inclination sensor is directly used as the inclination angle of the bucket portion, so that the calculation is further simplified. Then, the measurement value of the first tilt sensor can be used to control only the rotation angle of the arm. Alternatively, the link mechanism may be configured so that the rotation angle of the bucket (second member) is larger than the rotation angle of the fourth member, instead of being a perfect parallelogram. As a result, the fourth
Since the detection angle range of the tilt angle of the second tilt sensor provided on the member can be narrowed, the size of the second tilt sensor can be reduced.

Further, it is desirable that the bucket portion be replaceable. Accordingly, it is possible to cope with various excavation objects (surfaces), and it is possible to accurately measure the inclination angle of the bucket portion after the replacement according to the present invention. Further, the tilt angle measuring device of the present invention provides an arm (1) rotatably provided with respect to a predetermined support member (13).
4) a first tilt sensor (51), and an arm and a bucket of a link mechanism (24) for rotatably supporting the bucket (15) with respect to the arm thereof. Are the parts that are not integrally displaced (2
5) A second tilt sensor (52) arranged in (5), and a calculation unit for calculating a tilt angle of the bucket portion based on measurement information of the first and second tilt sensors and shape information of the link mechanism. (53). Such a tilt angle measuring device can be used for measuring the tilt angle of the bucket portion in the excavator of the present invention.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a hydraulic power shovel as an excavator of the present example,
In FIG. 1, the power shovel of this example is installed on the ground (or a riverbed or the like) at the site of construction work (or civil engineering work). This power shovel is used in a process of excavating a groove 3 having a rectangular section whose bottom surface 3a is substantially horizontal on the ground.

In FIG. 1, a main body 1 of a power shovel is placed on the ground via a track 12 for forward and backward movement.
The operator's seat (not shown) controls a power shovel at a console 33 (see FIG. 2) in the cockpit 11. The main body 10 is installed on the caterpillar section 12 so as to be able to be driven to rotate, and a boom 13 as a support member (or a member for suspension) is connected to the main body 10 in a state in which the inclination angle can be controlled with respect to the main body 10. The arm 14 is rotatably connected to the distal end of the arm 13 via a shaft 31, one end of the holding member 30 is rotatably connected to the distal end of the arm 14 via a shaft 27, and the earth and sand are integrally formed with the holding member 30. A box-shaped bucket 15 (corresponding to a bucket portion of the present invention) having an open end portion for directly excavating a hole is fixed. Bucket 1
The bottom surface 15a of the claw portion provided at the bottom of the opening at the end of the tip 5 is substantially flat, and in this example, the bottom surface 15a is regarded as the bottom surface of the bucket 15.

One end of a first hydraulic cylinder 16 extending from the main body 10 has a boom 13 via a rotatable shaft 17.
The tilt angle of the boom 13 with respect to the main body 10 is controlled by the expansion and contraction of the first hydraulic cylinder 16. Similarly, the second hydraulic cylinder 18 is connected to the boom 13 and the arm 14 via rotatable shafts 19 and 20, respectively, and the rotation angle of the arm 14 with respect to the boom 13 is controlled by the expansion and contraction of the second hydraulic cylinder 18.

Further, one end of a rod-shaped link member 25 is rotatably connected to a shaft 26 inside a shaft 27 at the tip of the arm 14, and a shaft 29 at the other end of the holding member 30 and the other end of the link member 25. Rod-shaped link member 28 between shafts 23
Are connected. In this case, the rod-shaped portion between the shafts 26 and 27 at the tip of the arm 14 is connected to the link member 14a.
In this example, the link member 14a and the holding member 3
The link mechanism 24 is formed by connecting the link member 0, the link member 28, and the link member 25 in a parallelogram shape with rotatable shafts 27, 29, 23, and 26, respectively. The rotatable shaft 22 provided on the arm 14
Between the first hydraulic cylinder 2 and the shaft 23 of the link mechanism 24.
The rotation angle of the link mechanism 24 and the bucket 15 with respect to the arm 14 is controlled by the expansion and contraction of the third hydraulic cylinder 21. That is, the rotation angle of the bucket 15 with respect to the arm 14 changes as the shape of the link mechanism 24 changes due to expansion and contraction of the third hydraulic cylinder 21.

Further, the bucket 15 of this embodiment is
It is configured so that it can be replaced with a different bucket (not shown) having a different shape integrally with the bucket 0. The two shafts 27, 2 of the holding member (corresponding to the holding member 30) of the bucket after replacement.
9 is standardized to be the same as the holding member 30 before replacement, so that the bucket can be easily replaced.
It can be performed quickly.

A first inclination sensor 51 for measuring an inclination angle of the arm 14 with respect to a horizontal plane is fixed near the center of the arm 14, and a link member 25 above the link mechanism 24, that is, the arm 14 and the bucket 15. The second inclination sensor 52 for measuring the inclination angle of the link member with respect to the horizontal plane is also fixed to the link member which is not integrally displaced. Inclination sensors 51, 52
Has a measurement resolution of 0.1 ° in a detection angle range of approximately 120 ° (± 60 ° with respect to a horizontal plane) as an example, and a measurement accuracy (linearity) of approximately ± 1% (about ± 1 °). Having. Specific examples of the tilt sensors 51 and 52 will be described later. Detection signals of the tilt sensors 51 and 52 (measurement information)
Are supplied to a sub-control system 53 (see FIG. 2) in the cockpit 11 via a signal cable (not shown).

In this case, the arm 14 and the link mechanism 24
Is a part that does not directly touch the earth and sand during excavation work,
Tilt sensor 51 attached to arm 14, link mechanism 2
The tilt sensor 52 attached to a part of 4 and the signal cable from them are completely covered with dustproof and waterproof protective covers (not shown), respectively. Further, since the link mechanism 24 has a certain degree of shock absorbing effect, the tilt sensors 51 and 52 do not act on the bucket 15 itself. Therefore, the tilt sensors 51 and 52 always operate stably, and disconnection of the signal cables is also prevented.

FIG. 2 is a block diagram of the control system of the present embodiment. In FIG. 2, the control system is largely a power shovel system 1 and an inclination measuring system 2 (corresponding to the inclination measuring device of the present invention). And divided into In the power shovel system 1, an operator inputs various control information from a console 33 to a main control system 32 including a computer. The main control system 32 according to the control information
Controls the overall operation of the power shovel of FIG.
The operator operates the handle and clutch of the console 33 to control the movement of the caterpillar section 12 in FIG. 1 via the caterpillar drive system 35. At this time, the turning operation of the main body 10 is also controlled. At the same time, the operator operates various levers of the console 33 to extend and retract the first hydraulic cylinder 16, the second hydraulic cylinder 18, and the third hydraulic cylinder 21 of FIG. Control. Thereby, the boom 13, the arm 14,
And the excavation operation by the bucket 15 is performed.

At the time of this excavation operation, the operator makes an inclination angle (rotation angle) of the bottom surface 15a of the bucket 15 with respect to the horizontal plane,
Alternatively, the tilt angle measurement system 2 is provided so that the tilt angle of a deviation from a predetermined reference angle can be monitored. In the tilt angle measuring system 2, the two tilt sensors 5 of FIG.
The sub-control system 53 composed of a microcomputer receives detection signals 1 and 52 via an analog / digital converter (not shown).
(Corresponding to the operation unit of the present invention). The sub-control system 53 includes a RAM for holding data and a ROM in which a program is recorded, and an external electrically rewritable nonvolatile R as required.
Information (shape information) related to the shape of the link mechanism 24 in FIG. 1 is read from an OM (for example, a flash memory) 54. Then, the sub-control system 53 performs the following calculation using the measurement information of the inclination sensors 51 and 52 and the shape information of the link mechanism 24, thereby obtaining the inclination angle of the bottom surface 15a of the bucket 15 with respect to the horizontal plane (hereinafter, “output angle”). ").

FIG. 3A is an enlarged view of a portion from the boom 13 to the bucket 15 in FIG. 1. In FIG. 3A, the detection center of the first inclination sensor 51 of this embodiment is: Two shafts 26 and 2 on the arm 14 of the link mechanism 24
7, the inclination sensor 51 detects the inclination angle θ1 of the straight line passing through the centers of the two axes 26 and 27 with respect to the horizontal plane HP1 (this is referred to as “the arm 14 Angle of inclination with respect to the horizontal plane). Similarly, the detection center of the second inclination sensor 52 is
The tilt sensor 52 is located substantially on a straight line passing through the centers of the two axes 26 and 23 of the link mechanism 24, and the inclination sensor 52 is positioned on a horizontal plane of a straight line (the center axis of the link member 25) passing through the centers of the two axes 26 and 23. The inclination angle θ2 with respect to HP2 (this is regarded as “the inclination angle of the link member 25 with respect to the horizontal plane” in this example) is measured. The inclination angle of the bottom surface 15a of the bucket 15 with respect to the horizontal plane HP3, which is the calculation target (output angle), is defined as Φ. The sign of the inclination angle (deg) in the following description assumes that the value in the clockwise direction with respect to the horizontal plane is positive and the value in the counterclockwise direction is negative. Therefore, in FIG. 3A, the inclination angle θ1 is a positive value, and the inclination angle θ2 is a negative value.

First, the arm 14 with respect to the link member 25
(Hereinafter, also referred to as “input angle”) θ is as follows. θ = θ1−θ2 (1) Here, in order to calculate the output angle Φ from the two inclination angles θ1 and θ2, in this example, the lengths of the four sides of the link mechanism 24 in advance (see FIG. 3B) ) Length a of the link member 14a
(The distance between the shafts 26 and 27), the length b of the link member 25 (the distance between the shafts 26 and 23), and the length c of the link member 28 (the shaft 2
3, 29) and the length d of the holding member 30 (the shaft 2
7, the information of the measured lengths a, b, c, and d is stored in the ROM 54 of FIG. The inclination angle of the bottom surface 15a of the bucket 15 with respect to a straight line connecting the centers of the shafts 27 and 29, that is, the holding member 30
Is also measured in advance and stored in the ROM 54. In this example,
The bucket 15 can be exchanged with another bucket. The offsets of the inclination angles of the plurality of exchangeable buckets are stored in the ROM 54, and the changeover switch (not shown) allows the operator to input the corresponding offset information. Is configured. Furthermore, for convenience of calculation,
The length of one diagonal line of the link mechanism 24, that is, the axes 23, 2
Let e be the interval of 7.

FIG. 3B is a simplified view of the link mechanism 24. In FIG. 3B, the shafts 23, 26,
The angle sandwiching the triangular axis 26 with the vertex at 27 is (180
(Θ−θ), the length e of the side facing the axis 26 (the length of the diagonal line connecting the axes 23 and 27) e can be calculated from the cosine theorem as follows. e = {a ² + b ² −2abcos (180 ° −θ)} ^1/2 (2) Therefore, when the cosine theorem is applied to the triangle again, the axis 2
The angle φ1 sandwiching 7 can be obtained as follows.

Φ1 = cos ⁻¹ {(e ² + a ² −b ² ) / (2ea)} (3) Next, the axis 27 of the triangle having the axes 23, 29 and 27 as vertices
Is calculated from the cosine theorem as follows. φ2 = cos ⁻¹ {(d ² + e ² −c ² ) / (2de)} (4) Therefore, the angle between the straight line connecting the shafts 27 and 29 and the straight line connecting the shafts 26 and 27, that is, FIG. The angle .phi. Of the arm 14 with respect to the holding member 30 in ()) is as follows.

Φ = φ1 + φ2 (5) Also, since the inclination angle of the bottom surface 15a of the bucket 15 with respect to the straight line connecting the shafts 27 and 29 is φ0,
The horizontal plane HP3 which is a calculation target using the calculated value of the equation (4)
Angle (output angle) of the bottom surface 15a of the bucket 15 with respect to
Φ can be obtained as follows.

Φ = θ1−φ + φ0 = (θ1 + φ0) − (φ1 + φ2) (6) On the contrary, in order to calculate the input angle θ from the output angle Φ, FIG.
In (B), assuming that the length of the diagonal line connecting the shafts 26 and 29 is e ′, the angle φ (= −φ + φ0 + θ) in the expression (5)
Using 1), the length e 'can be calculated as follows. e ′ = (a ² + d ² −2adcos φ) ^1/2 (7) Then, using this length e ′, the input angle θ (= θ 1 −
θ2) can be calculated as follows. θ = 180 ° −cos ⁻¹ {(e ′ ² + a ² −d ² ) / (2e′a)} − cos ⁻¹ {(e ′ ² + b ² −c ² ) / (2e′b)} ( 8) As an example, the length of the link is a = 524 (mm), b =
827 (mm), c = 726 (mm), d = 611 (m
m), the tilt angle offset φ0 is set to + 10 °. If the inclination angle θ1 measured by the inclination sensors 51 and 52 is + 68 ° and the inclination angle θ2 is −23 °, the length e of one diagonal line from the equations (1) and (2) is as follows. Become.

E = 971.8 (mm) (9) When this result is substituted into the equations (3) and (4), the angle φ is as follows from the equation (5). φ = + 106.6 ° (10) By substituting the result, the inclination angle θ1, and the offset φ0 into the expression (6), the output angle φ is as follows.

Φ = −28.6 ° (11) Returning to FIG. 2, the sub-control system 53 has a bucket monitor 56 for displaying the information of the calculated output angle Φ, and the operator sets a target for the sub-control system 53. An angle setting unit 55 for setting an output angle and the like is also connected. The angle setting unit 55 and the bucket monitor 56 are installed in the cockpit 11 of FIG. 1 at positions where the operator can operate them.

FIG. 6 shows a panel surface of the angle setting unit 55 and the bucket monitor 56. First, in the angle setting unit 55 of FIG. 6, the first display unit 63 outputs the output of the bucket 15 of FIG. The target value (set angle) of the angle Φ is displayed.
Are displayed on the display unit 65 of FIG. 3A.
The output angle Φ (actually measured value: bucket angle) of the bucket 15 calculated by the sub-control system 53 based on the measured value of (1) is displayed. The output angle Φ is normally displayed, for example, in a degree (deg) with a resolution of 0.1 °, but in addition, a mode in which the output angle Φ is displayed in% with respect to the measurement range, and a mode in which the output angle is displayed with division / minute with respect to the measurement range are provided. . These display modes can be switched by the display switch 66. Further, the angle setting section 55 is also provided with an error display lamp 73 which is lit when an error of an actually measured value (a value obtained by calculation) with respect to a target value of the output angle Φ is + or-.

In order for the operator to set a desired angle on the first display section 63, an angle setting switch 62A for changing the angle in the + direction and an angle setting switch 62B for changing the angle in the-direction. , And a setting switch 6 for setting an angle in the display unit 63 to the sub control system 53
4 are provided. In this regard, for example, bucket 1
5 is arranged at a predetermined angle with respect to the excavation surface, and the output angle Φ of the bucket 15 is set to a predetermined value (0 ° or 90 ° in this example).
Initial setting switches 68 and 6
9 are provided. In this case, when the operator operates the first initial setting switch 68, + 90 ° is preset as an actual measurement value of the output angle Φ in the second display unit 65, and this setting information is also transmitted to the sub control system 53. Supplied. On the other hand, when the second initial setting switch 69 is operated,
At the second display section 65, 0 ° is preset as an actual measurement value of the output angle Φ, and at the same time, the setting information is displayed on the sub control system 53.
Also supplied. Thereafter, the tilt angle of the bucket 15 is displayed with the preset value as an initial value. For example, when the power is turned on, as an automatic initial setting, the output angle Φ of the bucket 15 is displayed to be 0 ° when it is parallel to the horizontal plane. In these cases, as described above, the output angle Φ has a positive value in the clockwise direction with respect to the horizontal plane and a negative value in the counterclockwise direction with respect to the horizontal plane.

The target value and the actual measured value of the output angle Φ and the information of the inclination angle measured by the inclination sensors 51 and 52 are transmitted from the sub control system 53 to the main control system 32 of the power shovel system 1 in FIG. Supplied. In this example, the output angle Φ
The operator controls the tilt angle of the bucket 15 in a manual manner based on the information of the target value and the actual measurement value, but an automatic control method in which the main control system 32 automatically controls the tilt angle of the bucket 15 is also possible. It is. In the case of automatic control, for example, in FIG. 3A, the output angle Φ of the bucket 15 is changed in parallel with the operation of the operator controlling the hydraulic cylinders 16 and 18 to control the operations of the boom 13 and the arm 14. The main control system 32 may control the rotation angle of the bucket 15 via the hydraulic cylinder 21 so as to be maintained at the target value.

Further, the inclination angle measuring system 2 of the present embodiment includes:
A function is also provided for generating an alarm sound when an error of the actually measured value of the output angle Φ of the bucket 15 with respect to the target value exceeds a predetermined allowable range. Therefore, the angle setting unit 55 in FIG.
A volume changeover switch 67 for switching the level of the alarm sound is provided. As the alarm sound, besides the buzzer sound, a sound such as "the error is positive" can be used. As an example, when the error of the output angle Φ exceeds ± 0.5 ° (the bucket monitor 56 described later)
When the display resolution is 1 °) or when the display resolution exceeds ± 1 ° (when the display resolution is 2 °), an alarm is sounded. At this time, the error is +
The alarm sound in the case of (1) and the alarm sound in the case of (-) are set so that they can be easily distinguished, for example, by "voice error is positive" or "error is negative". This allows the operator to recognize the error of the output angle Φ of the bucket 15 in a state where the operator concentrates on the digging surface without necessarily looking at the later-described bucket monitor 56, thereby improving work efficiency.

Next, in the bucket monitor 56 shown in FIG.
5, the bottom surface 1 of the bucket 15 set on the first display unit 63
The error of the calculated value (actually measured value) of the output angle Φ displayed on the second display section 65 with respect to the target value of the inclination angle (output angle Φ) of 5a is displayed. Further, a sensitivity changeover switch 70 for switching the sensitivity of the error is also provided, and the operator can operate the switch 70 to switch the error resolution to two types, for example, 1 ° and 2 °. . The current resolution is displayed on the display 72.
Will be displayed. When the resolution of the error display is 1 °, when the error is within ± 0.5 °, the display 7
When only one “OK” light-emitting part in the center of 1 emits red light and the error is 1.5 ° to 2.5 °,
Two light emitting units on the + side from immediately above the center of the display unit 71 emit green light. And the error is -1.5 °-
When the angle is 2.5 °, two light emitting units emit yellow light from immediately below the center of the display unit 71 to the − side. Accordingly, the operator can visually confirm the error of the output angle Φ within a range of approximately ± 5 ° with a resolution of 1 ° from the display on the display unit 71. Similarly, when the resolution is switched to 2 °, the operator changes the error of the output angle Φ by approximately ± 10.
° can be confirmed within the range. Then, for example, at the final stage of excavation, the operator operates the movement of the bucket 15 so that the error of the output angle Φ falls within an allowable range.

Next, using the power shovel of this embodiment, FIG.
An example of the operation at the time of excavating the trench 3 whose bottom surface 3a is a substantially horizontal surface on the ground will be described. In this case, the operator of the power shovel sets 0 ° as the target angle on the first display unit 63 using the angle setting unit 55 of FIG. 6, and operates the setting switch 64 to change the target angle to the sub control system 53.
, The volume switch 67 is operated to set the level of the error alarm sound, and the bucket monitor 5
The display sensitivity of the error of the display unit 71 is set by using the sensitivity changeover switch 70 of No. 6. It should be noted that, when the bottom surface 15a of the bucket 15 is parallel to the horizontal plane due to the automatic initialization, the actually measured value (the value obtained by calculation) of the output angle Φ of the bucket 15 displayed on the second display unit 65. Is 0 °
It is set to be. In response, the sub-control system 5
Reference numeral 3 denotes an output angle Φ of the bucket 15 obtained by setting 0 ° on the first display unit 63 of the angle setting unit 55 and calculating based on the measurement values of the inclination sensors 51 and 52 of the second display unit 65. Is displayed at a predetermined sampling rate (for example, about 100 Hz), and the error of the actually measured value of the output angle Φ of the bucket 15 with respect to the target value is indicated by the error display lamp 7 of the angle setting unit 55.
3 and a bar code format display section 71 of the bucket monitor 56, and further generates an alarm sound corresponding to the error.

In this state, the operator operates the power shovel shown in FIG. 1 to excavate the groove 3, and at the final stage of excavating the bottom surface 3a, displays an error on the display unit 71 of the bucket monitor 56 or an error thereof. Based on the alarm sound according to
The bucket 15 is moved along the bottom surface 3a so that the bottom surface 15a of the bucket 15 is parallel to the horizontal plane to excavate earth and sand.

FIG. 4 shows an example of the movement of the bucket 15 at the final stage of the excavation. As shown in FIG. 4A, the bottom surface 15a of the bucket 15 is horizontally indicated by an arrow B on the bottom surface 3a of the groove. When moving in the direction shown in FIG.
In the center of “O” in the error display 71 of the bucket monitor 56 of
B ”so that only the red light emitting portion of“ K ”emits light.
3, the operation of the arm 14 and the bucket 15 is controlled.
Thereby, the bucket 15 moves horizontally on the bottom surface 3a as shown in FIG.
Can be excavated horizontally. Thereby, the bottom 3
a can be prevented from being over-excavated. Instead of this operation, the boom 1 is maintained while the bucket 15 is kept horizontal.
By fixing the arm 3, the bucket 14, and the bucket 15, and excavating the bottom surface 3a by moving the caterpillar portion 12 in FIG. 1, the bottom surface can be easily excavated horizontally.

Next, using the power shovel of this embodiment, FIG.
As shown in the figure, the inclined surface 4 is formed at a predetermined angle α with respect to the horizontal plane.
An example of the operation when excavating on a plane intersecting at (α is about 45 °, for example) will be described. In this case, since the angle α is a counterclockwise angle with respect to the horizontal plane, the bucket 1
The target value of the inclination angle of 5 is -α. Accordingly, the operator sets -α as the target value of the output angle Φ on the first display unit of the angle setting unit 55 in FIG. In response, the sub-control system 5
3 displays an error of the output angle Φ of the bucket 15 with respect to the target value (−α) on the error display section 71 of the bucket monitor 56, and also generates an alarm sound corresponding to the error. Therefore, in the final stage of excavation of the inclined surface 4, the operator controls the operation of the boom 13, the arm 14, the bucket 15, and the caterpillar portion 12 so that the error is within an allowable range, thereby easily forming the inclined surface 4. Can be excavated in a plane at an angle α with respect to the horizontal plane.

In this embodiment, the inclined surface 4
Is partially completed, the setting switch 69 of the angle setting unit 55 in FIG. 6 is operated while the bottom surface 15a of the bucket 15 is pressed in parallel to the completed surface. Alternatively, the measured value of the output angle Φ of the bucket 15 may be preset to 0 °. In this case, the target value set in the first display section 63 may be set to 0 °, whereby the entire surface of the inclined surface 4 can be easily finished in parallel with the actually completed surface.

As described above, according to the power shovel of the present embodiment, the bucket based on the measured values of the tilt sensor 51 provided on the arm 14 and the tilt sensor 52 provided on the link mechanism 24 and the information on the shape of the link mechanism 24. Since the inclination angle of the bucket 15 is obtained by calculation, it is possible to accurately measure the inclination angle of the bucket 15 without providing a sensor for measuring the inclination angle in the bucket 15 itself and using only a small number of inclination sensors. The tilt angle of the bucket 15 can be controlled with high accuracy based on the measurement result. Further, since the tilt sensor is not arranged on the bucket 15, even when the bucket 15 is replaced with another bucket,
There is an advantage that the inclination angle of the bucket after replacement can be accurately measured and controlled.

Next, a specific example of the first tilt sensor 51 of FIG. 3 will be described with reference to FIG. Note that the second tilt sensor 52 can be similarly configured. 5B is a front view showing the tilt sensor 51, FIG. 5A is a cross-sectional view along the line AA in FIG. 5B, and FIG. 5C is the tilt sensor 51 in FIG. 5B.
FIG. 5 is a view showing a state in which is rotated about an axis parallel to a horizontal plane. As shown in FIGS. 5A and 5B, the tilt sensor 51 of the present example has a disc-shaped cavity made of an insulator. A first pair of semi-circular metal electrode plates 58 and a second pair of semi-circular metal electrode plates 59 are placed adjacent to each other inside a closed container 57 having the same. An insulating liquid (for example, oil) 60 is filled so as to fill half of the space inside 59. In this case, since the surface of the liquid 60 is parallel to the horizontal plane HP1, the capacitance C1 between the first electrode plate 58 and the second electrode plate 5 in the state of FIG.
9 is equal to the capacitance C2 during the rotation of the electrode plate 5 when the inclination sensor 51 rotates by the angle θ1 as shown in FIG.
Since the capacitance C1 between the electrodes 8 increases and the capacitance C2 between the electrode plates 59 decreases, the inclination angle θ1 is detected with high accuracy by detecting the difference between the two capacitances C1 and C2. be able to.

Therefore, in the external detection circuit 61, the capacitance C1 between the electrode plates 58 and the capacitance C1 between the electrode plates 59 are determined.
2 and generates a detection signal corresponding to the difference between these two capacitances C1 and C2, and outputs this detection signal as a signal indicating the inclination angle θ1 of the inclination sensor 51 with respect to the horizontal plane. That is, the tilt sensor 51 of the present embodiment is a differential capacitance type tilt sensor. In addition to this, for example, an optical tilt sensor or the like that detects the rotation angle of the rotating body serving as a reference of the horizontal plane with respect to the external container by an optical rotary encoder method can be used.

In the above embodiment, FIG.
As shown in the figure, the second inclination sensor 52 is connected to the link mechanism 24.
Is fixed to the upper link member 52, so that the influence of vibration during excavation of the bucket 15 is minimized.
However, for example, in the case where the link member 25 is shortened due to the structure and the installation space for the inclination sensor 52 is narrowed,
The outer link member 2 is another member that is not displaced integrally with the arm 14 and the bucket 15 in the link mechanism 24.
8 may be provided with a tilt sensor 52. Further, the link mechanism 24 is not limited to a parallelogram structure,
For example, it may be triangular or any other shape,
Also in these cases, the second tilt sensor 52
And a member that does not displace integrally with the bucket 15.

In the above embodiment, the inclination sensors 51 and 52 detect the inclination angle with respect to the horizontal plane. However, in FIG. 3A, for example, when the inclination angle of the boom 13 with respect to the horizontal plane is measured by another sensor or a level, the relative position of the arm 14 with respect to the boom 13 instead of the first inclination sensor 51 is changed. Using a tilt sensor such as a rotary encoder for detecting the rotation angle,
Instead of the inclination sensor 52, an inclination sensor such as a rotary encoder that detects a relative rotation angle of the link member 25 with respect to the arm 14 may be used.

In the above embodiment, the present invention is applied to a power shovel, but the present invention is applied to a wheel loader having a bucket and an excavator such as a grader having a blade (corresponding to a bucket portion). Can also be applied. In the former case, as an example, the inclination angle of the bucket is detected by the present invention, and the angle of the road surface of the bucket is detected from the difference between the detection result and the inclination angle of the wheel loader main body. In the latter case, for example, the tilt angle of the blade is detected by the present invention.

The present invention can also be applied to a rotary car for snow removal as an excavator. In this case, the attack angle (crossing angle) of the rotary auger portion with respect to the road is detected from the angle difference between the main body of the rotary car and the rotary auger portion (rotating blade portion for snow removal) according to the present invention. Further, the above-described embodiment is an excavator having a traveling function according to the present invention,
That is, it is applied to a self-propelled power shovel,
The present invention relates to, for example, the arm 14, the link mechanism 24 of FIG.
Only the excavation mechanism including the bucket 15 and the hydraulic cylinder 21 is supported by a predetermined support mechanism, and the present invention can be applied to a construction in which a river is expanded. In the present invention, the portion including only the excavating mechanism is also regarded as a “digging device in a narrow sense”.

As described above, the present invention is not limited to the above-described embodiment, and can take various configurations without departing from the gist of the present invention.

[0053]

According to the present invention, since two inclination sensors are disposed in a portion displaced in a predetermined positional relationship with respect to the bucket portion of the excavator, a sensor of an inclination angle with respect to the bucket portion is provided. The tilt angle of the bucket portion can be accurately measured with a small number of sensors without directly attaching. Then, there is an advantage that the inclination angle of the bucket portion can be accurately controlled by using the measurement result.

Further, according to the present invention, since the inclination angle sensor is not arranged in the bucket portion, when the bucket portion is replaced, the inclination angle of the bucket portion after replacement is accurately determined. There is an advantage that can be measured.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a power shovel according to an example of an embodiment of the present invention, in which a section of a ground is shown.

FIG. 2 is a block diagram showing a control system of the power shovel of FIG.

FIG. 3 (A) is a view from a boom 13 to a bucket 15 in FIG. 1;
FIG. 3B is an enlarged view showing the mechanism described above, and FIG. 3B is a simplified view of the link mechanism 24 shown in FIG.

FIG. 4 is an explanatory diagram of an operation when the bottom surface 15a of the bucket 15 is horizontally moved to excavate the bottom surface 3a of the groove.

FIG. 5 is a diagram showing a specific example of an inclination sensor 51.

6 is a diagram showing an angle setting unit 55 and a bucket monitor 56 of the tilt angle measuring system 2 in the control system of FIG.

7 is a cross-sectional view of the ground surface when excavating an inclined surface using the power shovel of FIG. 1;

FIG. 8 is a cross-sectional view of a ground used for explaining a method of measuring a tilt angle of a bucket 15 of a conventional power shovel.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Power shovel system, 2 ... Inclination angle measuring system, 10 ... Body part, 11 ... Cockpit, 13 ... Boom, 14
... Arm, 15 ... Bucket, 16, 18, 21 ... Hydraulic cylinder, 24 ... Link mechanism, 25,28 ... Link member,
Reference numeral 30: holding member, 51, 52: tilt sensor, 53: sub-control system, 55: angle setting unit, 56: bucket monitor

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-156126 (JP, A) JP-A-5-311691 (JP, A) JP-A-62-67208 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) E02F 9/26 E02F 3/38 E02F 3/43

Claims (7)

(57) [Claims] 1. A driving method of an excavator for excavating a surface to be machined by using a bucket portion rotatably provided to an arm portion via a link mechanism, wherein a first inclination sensor is provided on the arm portion. Attachment, a second tilt sensor is attached to a portion of the link mechanism that does not integrally displace with the arm portion and the bucket portion, and based on measurement information of the first and second tilt sensors. A method for driving an excavator, comprising: calculating an inclination angle of the bucket portion; and controlling the inclination angle of the bucket portion based on the calculation result. 2. The first and second inclination sensors each measure an inclination angle of a measurement target part with respect to a horizontal plane, and the inclination angle of the bucket part with respect to a horizontal plane based on the measurement information and the shape information of the link mechanism. The driving method of the excavator according to claim 1, wherein is calculated. 3. The method according to claim 1, wherein the bucket is moved relative to a surface to be processed in a state where the bucket is set within a target range of the inclination based on a calculation result of the inclination of the bucket. The driving method of an excavator according to claim 1 or 2, wherein 4. An excavating apparatus comprising: an arm portion rotatably provided to a predetermined support member; and a bucket portion rotatably provided to the arm portion via a link mechanism. A driving unit that rotationally drives the bucket unit with respect to the unit via the link mechanism; a first inclination sensor provided in the arm unit; and the arm unit and the bucket unit in the link mechanism. The second provided on the part which is not integrally displaced
An excavator, comprising: a tilt sensor according to (1), and a calculating unit that calculates a tilt angle of the bucket unit based on measurement information of the first and second tilt sensors. 5. The first and second tilt sensors each measure a tilt angle of a measurement target portion with respect to a horizontal plane, and the link mechanism includes a first end portion of the arm portion.
A member, a second member integrally provided with the bucket portion, a third member connecting the tip portion of the driving portion and the bucket portion, one end of the first member, and one end of the third member. And a fourth member that connects the first and second members to each other in a parallelogram shape via a rotatable fulcrum. The second inclination sensor measures an inclination angle of the fourth member of the link mechanism. The excavator according to claim 4, wherein the calculation unit calculates an inclination angle of the bucket unit with respect to a horizontal plane based on the measurement information and the shape information of the link mechanism. 6. The excavator according to claim 4, wherein the bucket portion is replaceable. 7. A first tilt sensor disposed on an arm portion rotatably provided with respect to a predetermined support member, and a link mechanism for rotatably supporting the bucket portion with respect to the arm portion. The second arm portion and the bucket portion are disposed at portions that are not integrally displaced.
A tilt sensor, and a calculation unit that calculates a tilt angle of the bucket unit based on measurement information of the first and second tilt sensors and shape information of the link mechanism. apparatus.