JPH0713576B2 - Mass measurement method with front loader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention rapidly measures the mass of agricultural products such as hay and compost, and many materials related to agricultural production such as earth and sand in the process of transportation and loading. The present invention relates to a mass measurement method that uses a tractor-mounted front loader.

[Conventional technology]

In general, it is extremely important for agricultural management to accurately grasp the production amount of coarse substances such as grass and compost, which are agricultural products, and the input amount of the produced compost to the fields.

Therefore, conventionally, in order to grasp the production amount of coarse substances such as hay and compost, or the input amount of produced compost into the fields, weigh it with a truck scale or load meter, or rely on experience and intuition. It was almost always the case.

[Problems to be Solved by the Invention]

However, in the above-mentioned conventional measurement method, there are few cases where each farm installs a truck scale or load meter, and under the present circumstances, it is possible to grasp the accurate production amount and input amount for measurement by experience and intuition. Difficult and
Since it is difficult to measure each time with continuous work at the site where the product is handled, there is a demand for a more scientific and rapid technical development for measuring the mass of coarse substances etc. on the spot. There is.

The present invention has been made in view of the above circumstances, and in the process of handling the mass of agricultural products such as hay and compost mainly handled by tractor-mounted front loaders in the agricultural field, materials, and the like in the front loader, It is an object of the present invention to provide a mass measurement method using a tractor-mounted front loader that enables the mass of coarse materials to be easily measured.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention is a front loader with a fork mounted on the front or rear of a tractor so as to be able to move up and down, and controls the elevation of the front loader using a hydraulic device equipped on the tractor. In the method of detecting the oil pressure of the lifting hydraulic cylinder and the oil pressure of the attitude control cylinder that controls the attitude of the fork, and measuring the weight of the substance loaded on the fork by these, the front loader comprises: For the lifting hydraulic cylinder that is solely responsible for lifting and lowering control of the arm section, and the attitude control cylinder that is provided on the arm section so that the fork section does not tilt in conjunction with the lifting and lowering of the arm section. When a substance is loaded on the front loader, the arm part of the front loader is raised and lowered to a predetermined angle while the fork part is horizontally controlled. By detecting the oil pressure on each piston rod side and cylinder chamber side applied to both hydraulic cylinders by its mass, calculate F _A applied to the fork hydraulic cylinder and force F _B applied to the arm hydraulic cylinder from these oil pressures, Arm hydraulic cylinder F (θi), G (θi), H which is a function of the vertical angle (arm angle) with the vertical direction
(.Theta.i) using the formula: Wi = F (θi), characterized by being adapted to measure the mass of the loading substance by _{F A -G (θi) F B} -H (θi).

[Action]

According to the above-mentioned measuring method, there are two sets of hydraulic cylinders, a hydraulic cylinder for controlling the elevation of the front loader arm part and a hydraulic cylinder for controlling the direction of the loading part (fork part) of the front loader tip attachment. When a substance is loaded on the loading section of the loader, the pressure applied to both hydraulic cylinders and the elevation angle of the front loader arm section are detected, and the weighing equation that is not affected by these changes in the center of gravity of the loaded article is used to easily Since it is possible to measure the mass of, the on-site and quick measurement can be performed.

〔Example〕

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view of a front loader attached to a front portion of a tractor applied to the present invention. In the drawing, reference numeral 1 is a tractor body, and 2 is one end thereof rotatably via a fulcrum 3 of the tractor body 1. The supported arm portion 4 is a fork portion attached to the tip of the arm portion 2 via a parallel link mechanism 5,
Reference numeral 6 denotes a hydraulic cylinder A for raising and lowering the arm portion 2, and one end of the hydraulic cylinder A is rotatably supported at a predetermined position of the arm portion 2 through a fulcrum 8 and the other end is pivotally supported at a predetermined position of the parallel link mechanism 5. Each hydraulic cylinder B is shown.

The hydraulic cylinder A6 and the hydraulic cylinder B7 are both reciprocating type, and two hydraulic cylinders are arranged in parallel.

Further, the hydraulic circuits of the hydraulic cylinder A6 and the hydraulic cylinder B7 are respectively configured as shown in FIG.
The hydraulic pressure from the hydraulic pump 9 is passed through the manually operated valve 10 to the cylinder chambers 6a and 7a of both hydraulic cylinders A6 and B7 and the rod chamber 6
It is pumped alternately to b and 7b.

Then, the force F _A kgf, F acting on both hydraulic cylinders A6 and B7
_{When B} kgf is controlled to be in a fixed position, the following theoretical formulas (1) and (2) hold.

F _A = 2 (P ₁ S ₁ −P ₂ S ₂ ) ・ ・ ・ ・ ・ ・ (1) F _B = 2 (P ′ ₁ S ′ ₁₋ P ′ ₂ S ′ ₂ ) ・ ・ ・ (2) Where P ₁ , P ′ ₁ = pressure acting on the piston surface from the cylinder side: k
gf / cm ₂ P ₂ , P ′ ₂ = pressure acting on the piston surface from the piston rod side: kgf / cm ₂ S ₁ , S ′ ₁ = effective piston cross-sectional area on the cylinder side: cm ₂ S ₂ , S ′ ₂ = piston The effective piston cross-sectional area on the rod side is cm ₂ .

From this, the force F _A applied to both hydraulic cylinders A6 and B7
kgf, F _B kgf is the cylinder chamber 6 in each hydraulic piping.
Transducer pressure on the a, 7a side and the rod chamber 6b, 7b side
16. By measuring with the static strain gauge 17, it can be easily obtained by the equations (1) and (2).

In the front loader thus configured, the load Wikg is loaded on the L _X position of the fork portion 4, the hydraulic cylinder B7 is controlled when the arm portion 2 is moved up and down, and the fork portion 4 is always held horizontally. In this state, the arm 2 is moved up and down,
At the arm angle θi of the hydraulic cylinder A6 when the hydraulic cylinder A6 is once stopped, the load Wi and the moments of the forces F _A and F _B applied to the hydraulic cylinders A6 and B7 for the fork portion 4 and the arm portion 2, respectively, are calculated as follows. 2 and the weight of the fork portion 4 are taken into account and rearranged, as shown in the following equation (3), the force is increased regardless of the load position on the fork portion 4.
The load capacity Wi can be easily calculated by simply measuring FA and FB.

Wi = αF _A −βF _B (3) In this equation, α and β are constants at the arm angle θi.
If the angle θi is determined, these constants can be calculated by assuming that they are known from specifications indicating the dimensions and positional relationship of the front loader. Therefore, α and β are expressed by the following equations (4) and (5) as functions of θi.

α = F (θi) ···· (4) β = G (θi) ···· (5) Here, the arm angle θi is set to 30,39,48 degrees. The calculation result when the test was performed is shown in Table 1.

Further, although the formula (3) is a formula ignoring the mass of the arm part 2 and the like, in reality, even if no load is loaded on the fork part 4, since the force acts on the hydraulic cylinders A6 and B7,
The loading load on the fork portion 4 is represented by the equation (6) in which the initial load Wkg is subtracted.

Wi = αF _A −βF _B −W (6) Since the position of the center of gravity of the arm 2 and the like changes due to the change in the arm angle θi, W is also expressed by the equation (7) as a function of θi. .

W = H (θi) ... (7) W is α and β of the equations (4) and (5) obtained by calculation, and the arm angle θi with no load on the fork portion 4, At this time, by measuring the hydraulic pressure applied to each hydraulic cylinder A6, B7, F _A ,
It can be obtained by finding F _B , substituting it in equation (3), and replacing Wi with W.

As described above, according to the weighing formula by the front loader, if the arm angle θi is constant, α and β can be calculated. W is the hydraulic cylinders A6 and B7 when the fork portion 4 is unloaded and the arm angle is θi.
It can be determined by measuring the pressure applied to.

If each coefficient is determined in this way, if the load is loaded on the fork portion 4 and the arm angle is θi, the hydraulic pressures of the hydraulic cylinders A6 and B7 are measured to obtain F _A and F _B. 6)
The mass of the loaded luggage can be easily weighed according to the formula.

However, since there are various types and sizes of front loaders, it is not practical to calculate each coefficient of the equation (6) for each type and size, and it is also possible to secure high weighing accuracy. Since it is difficult, it is desirable to use the calibration method.

That is, equation (6) is shown as equation (8) as a function depending on the arm angle θi.

_{Wi = F (θi) F A} -G (θi) F B -H (θi) ····
(8) In this formula (8), two or more known weights having different masses are prepared, loaded on the fork part 4, and the hydraulic pressures of the hydraulic cylinders A6 and B7 when the arm angle θi is constant are set. By measuring and determining the forces F _A and F _B , and substituting these into Eq. (8) and performing multiple regression analysis, F (θi), G (θi), H (θ
i) can be easily obtained.

For example, the known weights are 210 kg and 406 kg, two levels, the center of gravity of the load on the fork 4 is two levels, 0 cm and 80 cm, and
The arm angle θi is 30, 39, 48 when the arm angle θi is fixed and the arm part 2 is raised and stopped, and when the arm part 2 is lowered and stopped. Table 2 shows an example of the result of the calibration method at the time of degrees.

In both cases, the partial correlation coefficient is close to 1.0, and according to this method,
It shows that the mass of the substance loaded on the fork part 4 can be weighed with high accuracy. Further, when a weight of 320 kg is actually stacked on the fork portion 4 and the error rate with the weight obtained by the equation (8) from the hydraulic pressure measurement of both hydraulic cylinders A6 and B7 is obtained, the arm angle θi is 30, 39, 48. 1% in both cases
It has been demonstrated that it can be weighed in and out with high accuracy.

It should be noted that by taking a step further, the transducers 15 and 16 are used to detect the hydraulic pressure of both hydraulic cylinders A6 and B7, and this is connected to a one-chip microcomputer, and by combining equation (8) and the calibration software, the fork is immediately released. The loaded weight of the unit 4 can be displayed.

〔The invention's effect〕

As described above, according to the mass measurement method by the front loader of the present invention, the load applied to the hydraulic cylinder between the fork part and the arm part of the tractor-mounted front loader and the loading load by detecting the arm angle. It can be measured and the following effects can be obtained.

． Since the force is detected simultaneously at two points of the fork and the arm while the fork is horizontally controlled, the influence of the load center of gravity of the load on the fork is ignored regardless of the position. Yes, no special load modification is required.

． It becomes possible to easily manage the mass of intermediate products such as grass and compost, which contributes to the soundness and rationalization of agricultural management.

[Brief description of drawings]

FIG. 1 is a side view of a front loader applied to the front part of a tractor applied to the present invention, and FIG. 2 is a hydraulic circuit configuration diagram of a hydraulic cylinder. 1 ... Tractor body, 2 ... Arm part, 4 ... Fork part, 6 ... Hydraulic cylinder A, 7 ... Hydraulic cylinder B, 9
...... Hydraulic pump, 10 …… Manually operated valve, 15,16 …… Transducer, 17 …… Static strain gauge.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Sakae Kodera 1 Hitsujigaoka, Toyohira-ku, Sapporo-shi, Hokkaido Inside the Agricultural Experiment Station, Hokkaido (56) References JP-A-59-107217 (JP, A) JP-A-59-84119 (JP) , A)

Claims (1)

[Claims] 1. A front loader with a fork mounted on a front portion or a rear portion of a tractor so as to be able to move up and down, and a hydraulic cylinder oil for raising and lowering which controls the elevation of the front loader by using a hydraulic device equipped on the tractor. In the method of measuring the weight of the substance loaded on the fork by detecting the pressure and the hydraulic pressure of the attitude control cylinder that controls the attitude of the fork, the front loader only controls the raising and lowering of the arm. In a lifting hydraulic cylinder that is shared and an attitude control cylinder that is provided on the arm part so as to prevent the fork part from tilting in conjunction with the lifting and lowering of the arm part, when a substance is loaded on the fork part, With the fork part controlled horizontally, the arm part of the front loader is moved up and down to a specified angle, and at that time, the hydraulic pressure is adjusted by the mass of both arms. The hydraulic pressure on the piston rod side and the cylinder chamber side applied to the Linda is detected, and the force F _A applied to the fork hydraulic cylinder and the force F _B applied to the arm hydraulic cylinder from these hydraulic pressures.
F (θi), G (θi), H, which is a function of the ascending / descending angle (arm angle) that the arm hydraulic cylinder makes with the vertical direction.
(.Theta.i) using the formula: Wi = F (θi) F A -G (θi) F B -H (θi) by mass measurement by the front loader is characterized in that so as to measure the mass of the loading substance Law.