JP2749253B2 - Excavator bucket edge position detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention automatically collects necessary data on a front working machine system of a shovel equipped with a bucket of any shape and automatically detects a position of a blade edge of the bucket. How to do it.

[0002]

2. Description of the Related Art As shown in FIG. 4, a shovel is provided with an upper swing body and a front working machine system via a swing bearing 12 on a lower traveling body 11. In the front working machine system, a boom 13, a stick 14, and a bucket 15 are sequentially supported, and each member thereof is rotated by a boom cylinder 16, a stick cylinder 17, and a bucket cylinder 18. The movement of the tip of the bucket cylinder 18 is transmitted to the bucket 15 via the rod 20 with the swing of the idler link 19.

The front working machine system is provided with sensors for detecting the rotation angle of each member or the operation stroke of each cylinder, for example, a rotary or direct-acting potentiometer. , The movement amount of the stick 14 and the bucket 15 can be monitored.

In such a shovel, the following data A to F are required to calculate the coordinate position of the cutting edge of the bucket tip 15a (hereinafter referred to as bucket edge 1) in the front working machine system.

A. Boom link angle (or stroke of boom cylinder 16) Boom shape (pin position of boom 13) Stick link angle (or stick cylinder 17
Stroke) D. Stick shape (pin position of stick 14) Bucket link angle (actually, the stroke of bucket cylinder 18 or idler link 19
Monitor the angle of F). Bucket shape (the relative positions of the bucket cutting edge 1 and the bucket rod connection pin 2 with respect to the bucket stick connection pin 3) Further, in order to calculate the angle θ _b of the bucket back surface 15b with respect to the horizontal plane, in addition to the above data A to F And G. It is necessary to calculate the bucket shape (bucket angle α between the straight line between the pin 3 and the cutting edge 1 and the bucket back surface 15b).

[0006] In this type of front working machine system, the boom 13 and the stick 14 are rarely replaced, but the bucket 15 is replaced with one having a different shape as required. There are many variations in the bucket shape (the positions of the blade edge 1 and the pin 2 and the bucket back angle α), and it is necessary to measure and input each shape.

Here, as shown in FIG. 5, the bucket shape F is defined by an X-coordinate value X ₁₃ of the bucket edge 1 and a bucket 3 sizes may knowing the rod connecting pin 2 of the X-coordinate value X ₂₃ and Y-coordinate values Y _23.

Further, in order to calculate the angle θ _b of the bucket back surface 15b with respect to the horizontal plane, the above three numerical values X ₁₃ ,
The numerical value of the bucket back angle α of the bucket shape G only needs to be known in addition to X ₂₃ and Y ₂₃ .

Conventionally, in order to obtain these numerical values, the bucket shape was actually measured in advance, and the numerical values were input to a computer as input data.

[0010]

Therefore, it is necessary to measure the bucket shape for each variation of the bucket or each time the bucket is modified, and to input the data as an external data to a computer. There are many variations, and it is not easy to measure and input each shape.

The present invention has been made in view of the above points, and even if a bucket having an arbitrary shape is moved while the bucket is mounted on a front working machine system of a shovel, necessary data is automatically obtained. It is an object of the present invention to provide a method capable of detecting the position of a blade edge and the like by collecting the data.

[0012]

According to a first aspect of the present invention, there is provided a shovel having a front working machine system, wherein a front work machine system of the shovel has a front work machine system mounted on a flat surface while a bucket of an arbitrary shape is mounted. By moving the work machine system and grounding the bucket blade edge several times at arbitrary different bucket angles, monitoring the working amount of each part of the front work machine system at the time of the grounding, and processing the data, the front work machine system Is a method for detecting the position of the blade edge of the bucket.

According to a second aspect of the present invention, in addition to the bucket edge position detecting method of the first aspect, the back surface of the bucket is grounded on a flat surface, and the operation amount of each part of the front working machine system at the time of the grounding is monitored. By calculating the data, the angle of the back surface of the bucket with respect to the horizontal plane is detected.

[0014]

According to the first aspect of the present invention, in a state in which a bucket of an arbitrary shape is mounted on a front working machine system of a shovel, the front working machine system is moved to ground the cutting edge of the bucket in a plurality of different postures. By monitoring each link angle of the front work machine system (boom, stick and bucket) at the time, and finding the bucket blade position with respect to the bucket stick connection pin, the bucket blade position in the front work machine system is automatically detected. .

According to a second aspect of the present invention, in addition to the plurality of attitudes of the first aspect, the angle of the bucket rear surface with respect to the horizontal plane is detected by detecting the bucket rear angle in a posture in which the bucket rear surface is grounded.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to an embodiment shown in the drawings. Note that various calculations are automatically performed by a computer mounted on the shovel based on an operation amount detection signal from a sensor provided in each operation unit of the front working machine system.

(Method of Calculating Bucket Edge Position in Front Work Machine System) <Target> In FIG. 4, in order to calculate the coordinate value of the edge of the bucket tip 15a (hereinafter referred to as bucket edge 1) in the front work machine system. For example, the following data is required.

A. Boom link angle (or stroke of boom cylinder 16) Boom shape (pin position of boom 13) Stick link angle (or stick cylinder 17
Stroke) D. Stick shape (pin position of stick 14) Bucket link angle (actually calculated from the stroke of bucket cylinder 18, the length of idler link 19, and the length of rod 20 due to earth and sand problems) Bucket shape (Cutting edge 1 and Pin 2 for Pin 3
Here, the bucket shape of F is defined by the bucket blade 1 and the bucket
It is determined by the relative position of the rod connecting pin 2, and FIG. 5 shows an example thereof. The origin in FIG. 5 is not limited to the pin 3 but may be the blade 1 or the pin 2.

That is, to determine the bucket shape,
It is only necessary to know the three sizes of the X coordinate value X ₁₃ of the bucket cutting edge 1 based on the bucket stick connection pin 3, the X coordinate value X ₂₃ and the Y coordinate value Y ₂₃ of the bucket rod connection pin 2.

Hereinafter, as shown in FIGS. 1 and 2, a method for calculating the bucket shape by grounding the bucket edge 1 while the bucket 15 is mounted on the front working machine system of the shovel is proposed. .

<Conditions> Now, when the numerical values A to E are known, of the pin positions shown in FIGS. 1 and 2, only the positions of pins 3, 4, and 5 can be calculated. is there.

Further, if the ground is flat, the Y coordinate of the bucket edge 1 can be calculated.

[0023] That is, the X coordinate X ₁ of the bucket edge 1 in Fig. 1, the bucket rod connection pins 2 X coordinate X
By calculating _2, and the Y-coordinate Y _2, it is possible to determine the bucket shape.

Here, as shown in FIG.
The bucket shape is determined by calculating the relative positions of the bucket blade 1 and the pin 2 with respect to the pin 3 from the data obtained when the bucket blade 1 is grounded in any of three postures with the link angle changed, for example. I decided to. The link angles of the boom 13 and the stick 14 may be arbitrary.

The following calculation method will be described using an arithmetic expression for inputting data three times in three orientations at which high measurement accuracy can be obtained. However, the input operation method is not limited to three inputs, and may be, for example, two input positions. May be input twice, that is, it may be input plural times.

<Calculation method> X ₁ , X ₂ , Y in FIG.
_The method of calculating ₂ is shown below.

FIG. 1 and Table 1 below show the pin positions when the bucket blade 1 is grounded in any three positions on a flat surface.

[0028]

[Table 1] When the position of the bucket stick connection pin 3 is considered as the origin, the Y coordinate position of the bucket cutting edge 1 can be expressed as the ground surface to the height h of the pin 3.

When the shape of the bucket is unknown, the positions of the pins 3 and the pins 4 to 4 ″ are calculated from the link angles of the boom 13 and the stick 14 and the stroke of the bucket cylinder 18.

The bucket blades 1 ', 1 "and the pins 2',
Each point of 2 ″ is located at a position where the cutting edge 1 and the pin 2 are rotated by θ ₁ and θ ₂ around the pin 3 (origin), respectively, and their coordinate values are calculated by a conversion matrix related to the rotation of the next rectangular coordinate. Is represented by the following equation.

[0031]

(Equation 1) The distance between the pins 2-4, 2'-4 'and 2 "-4" is always constant with the length r of the rod 20.

From the above conditions, the bucket cutting edges 1 to 1 ″,
Each position of the pins 2-2 "can be represented by the following five equations.

[0033]

(Equation 2) The unknown numbers in the above equation are five of X ₁ , θ ₁ , θ ₂ , X ₂ , and Y ₂ , and these are calculated by the above five equations.

First, when X ₁ is eliminated from the equations (1) and (2),

[0035]

(Equation 3) Next, according to the equations (3), (4) and (5), X ₂ , Y
_{If 2} is represented by θ ₁ and θ ₂ ,

[0036]

(Equation 4) Formulas (9) are obtained by substituting the formulas (7) and (8) into X ₂ and Y _{2 in the} formula (3).

Next, from equation (6),

[0038]

(Equation 5) The equation obtained by substituting equation (11) for θ _{2 in} equation (9) is (1)
Assuming equation (2), θ ₁ is calculated from equation (12). Further, θ ₂ is calculated by substituting θ ₁ into equation (11).

Next, θ ₁ and θ ₂ are expressed by the following equations (1).
By substituting into equations (7) and (8), X ₁ ,
X ₂ and Y ₂ can be calculated respectively.

The calculated X ₁ , X ₂ ,
Y ₂ is the coordinate value of the bucket cutting edge 1 and the bucket rod connection pin 2 with respect to the bucket stick connection pin 3, and the bucket shape can be specified by these.

Next, a calculation method using the multi-plan will be described.

1. Let θ ₁ be a variable. Here, temporarily
Substitute 1000 rad.

2. Using the equation (11), θ ₂ is calculated.

3. X ₂ and Y ₂ are calculated from the equations (7) and (8).

4. X ₂ and Y ₂ are substituted into equation (3).

5. (3) Yuku by changing the value of θ ₁ until you are satisfied.

Here, the value is added in increments of 1/1000 rad.

6 Calculate X ₂ and Y ₂ at θ ₁ satisfying the expression (3).

7. (1) to calculate the X ₁ from the formula.

X ₁ , X ₂ , and Y ₂ are calculated by the above methods 1 to 7.

Next, referring to FIG. 1, the coordinate system is shifted clockwise around the bucket stick connection pin 3 by tan ^-1 (h / X ₁ ).
By rotating the bucket rod 1 and the bucket stick connection pin 3 as shown in FIG. 5, the bucket rod connection pin 2 can be represented by a horizontal coordinate system.
Coordinate value X for the bucket stick connection pin 3
₂₃ and Y-coordinate values Y _23, bucket of the bucket blade tip 1
An X-coordinate value X ₁₃ for the stick connection pin 3 can be calculated by the following equation.

[0052]

(Equation 6) (Bucket method of calculating the angle theta _b with respect to the horizontal plane of the rear 15b) <target> Next, in any bucket shape shown in FIG. 4, in order to calculate the angle theta _b with respect to the horizontal plane of the bucket rear 15b is the following Data is needed.

A. Boom link angle (or stroke of boom cylinder 16) Boom shape (pin position of boom 13) Stick link angle (or stick cylinder 17
Stroke) D. Stick shape (pin position of stick 14) Bucket link angle (actually calculated from the stroke of bucket cylinder 18, the length of idler link 19, and the length of rod 20 due to earth and sand problems) Bucket shape (Cutting edge 1 and Pin 2 for Pin 3
Relative position). Bucket shape (bucket back angle α) That is, angle θ _b of bucket back 15b with respect to the horizontal plane
To calculate the bucket stick connection pin 3
In addition to the X coordinate value X ₁₃ of the bucket cutting edge 1, the X coordinate value X ₂₃ and the Y coordinate value Y ₂₃ of the bucket rod connecting pin 2, the straight line between the bucket stick connecting pin 3 and the bucket cutting edge 1 and the bucket back surface 15 b It is necessary to obtain a total of four numerical values of the bucket back angle α formed by

Here, since the three numerical values of the bucket edge position X ₁₃ and the pin positions X ₂₃ and Y ₂₃ for determining the bucket shape are calculated by the method already described, only the method of calculating the remaining bucket back angle α will be described. I do.

<Calculation method> As shown in FIG. 3, the bucket back surface angle α is set by contacting the bucket back surface 15b with the ground while keeping the bucket 15 attached to the front working machine system of the shovel. calculate. less than,
A method of calculating the back angle α will be described.

Since the numerical values A to F are now known, the ones that can be calculated in FIG. 3 are the positions of the bucket edge 1 and the pins 2, 3, 4, and 5.

When the front working machine system is operated on a flat surface such that the bucket back surface 15b is in contact with the ground as shown in FIG. 3, the bucket back angle α is calculated as follows. .

Α = tan ⁻¹ {(Y ₃ −Y ₁ ) / (X ₃ −X ₁ )} Note that the coordinate value of the bucket edge 1 in the front working machine system is (X ₁ , Y ₁ ), Coordinate values are (X ₃ , Y ₃ )
And

Finally, in the above embodiment (including the calculation formula and the drawing), the display is made by the vertical rectangular coordinates, but the display may be made by the polar coordinates, and the present invention is not limited to the display format of the coordinate system.

[0060]

According to the first aspect of the present invention, by operating the front working machine system of the shovel equipped with the bucket, the cutting edge of the bucket is grounded a plurality of times, and the necessary data is automatically collected. Even if the bucket shape is arbitrary, the bucket shape can be automatically detected after the bucket shape is easily fixed while being attached to the front working machine system.

According to the invention described in claim 2, according to claim 1
By detecting the bucket back angle in addition to the bucket edge position, the angle of the bucket back to the horizontal plane can also be determined.
The bucket can be easily detected while attached to the front work machine system. Further, by using this bucket, the inclination angle of the ground with respect to the horizontal plane can be measured by contacting the back surface of the bucket with the ground.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a bucket blade edge position detecting method according to the present invention.

FIG. 2 is an explanatory diagram showing a ground contact state of a bucket blade edge in the detection method according to the first embodiment.

FIG. 3 is an explanatory diagram showing a bucket back angle detection method added to the above detection method.

FIG. 4 is an explanatory view schematically showing a shovel.

FIG. 5 is an explanatory diagram showing elements for determining a bucket shape.

[Explanation of symbols]

1 angle relative bucket edge 15 bucket 15b bucket back theta _b horizontal plane of the bucket rear

Claims (2)

(57) [Claims] 1. A shovel provided with a front working machine system, wherein a bucket of an arbitrary shape is mounted on the front working machine system of the shovel, and the bucket is moved at an arbitrary different bucket angle by moving the front working machine system on a flat surface. The shovel is characterized in that the cutting edge is grounded a plurality of times, the working amount of each part of the front working machine system at the time of the grounding is monitored, and the data is subjected to arithmetic processing to detect the bucket blade position in the front working machine system. Bucket edge position detection method. 2. A bucket edge position detecting method according to claim 1, wherein the back surface of the bucket is grounded on a flat surface, the operation amount of each part of the front working machine system at the time of the grounding is monitored, and the data is arithmetically processed. A method for detecting the position of a blade edge of a shovel, wherein the angle of the back surface of the bucket with respect to a horizontal plane is detected.