RU2589217C1 - Volumetric strain-gauging apparatus - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to agricultural machine building, particularly, to measuring instruments, and can be used for working members of tillers. For this purpose, an apparatus for volumetric strain-gauging plant comprising two frames, brackets for fastening to suspension system, a mechanism for attachment of working member, three rods, on each of which measuring links according to invention, frames are connected by means of three parallel tie ends are fixed by means of cardan joints, arrangement of rods provides movement of movable frame in transverse-vertical plane, and use of cardan joints allows avoiding twisting moving frame relative to fixed measuring links are transmitted compressive and tensile force parallel to direction of tie-rods. To ensure rigidity system attachment point of parallel rods to frame are arranged at vertices of isosceles triangles, inscribed in lateral faces of parallelogram.

EFFECT: objective of technical solution consists in development of design for volumetric strain-gauging plant, simultaneously measuring all three components of resistance force, which will allow more deeply studying effect of structural parameters of working members on their power parameters.

1 cl, 1 dwg

Description

The invention relates to the field of agricultural and forestry engineering, in particular to the design of measuring instruments, and can be used to study the power characteristics of the working bodies of tillage tools.

Known measuring device for the study of the working bodies of tillage machines, consisting of two series-connected parallelogram mechanisms oriented longitudinally and transversely in horizontal planes that are mounted on a frame having a coupling device. On the frame of the transversely oriented parallelogram mechanism there is a platform for fastening the working body. The rigidity of the system is achieved by connecting parallelograms with brackets mounted on the base, using measuring links oriented, respectively, longitudinally and vertically in horizontal planes. This design allows you to directly measure the longitudinal R _x and transverse R _y components of the resistance force. The disadvantages of the prototype include the inability to measure the vertical component of the resistance force and the complexity of manufacturing a structure with acceptable rigidity (Utility Model Patent No. 62701, G01L 5/13, published on April 27, 2007).

The closest in technical essence is the strain gauge hitch, which consists of three fixed rods similar to tractor hitch rods, each of which is equipped with a measuring link. When installing the working body, the system becomes stiff. Traction resistance R _{x is} obtained by summing the readings of the measuring links (Bartenev I.M., Goncharov P.E. Devices for measuring the traction resistance of mounted soil-cultivating implements on clearings / Voronezh State Forestry Academy. - Voronezh, 1998. - 8 pp., Ill. - Bibl .: 3 names - Russian. - Dep. At VINITI RAS 02.25.1998 No. 525-B1998).

The disadvantage of the prototype is the impossibility of separately fixing the vertical R _z , lateral R _{y of the} component resistance forces and the measurement error of the force R _x arising from the influence of bending moments on the measuring links.

The objective of the technical solution is to develop the design of a volumetric strain gauge installation that simultaneously measures all three components of the resistance force, which will allow a more in-depth study of the influence of the structural parameters of the working bodies on their force parameters.

To this end, in a volumetric strain gauge installation, comprising two frames, mounting brackets to the hinged system, a working body mounting mechanism, three rods, on each of which measuring links are installed, according to the invention, the frames are connected using three parallel rods, the ends of which are fixed by cardan hinges, moreover, the arrangement of rods ensures the movement of the movable frame in the transverse vertical plane, and the use of cardan hinges avoids twisting of the movable frame relatively motionless, while compressive and tensile forces are transmitted to the measuring links parallel to the direction of the rods. To ensure increased rigidity of the system, the points of attachment of parallel rods to the frames (centers of the cardan joints) are located at the vertices of isosceles triangles inscribed in the lateral faces of the parallelogram.

In FIG. 1 shows a strain gauge installation.

The installation consists of two frames 1 and 2, connected by three parallel rods 3, the ends of which are fixed by cardan joints 4, three tensometric links 5 mounted on each rod, the fastening mechanism of the working body 6 with the investigated working body 7 and mounting brackets to the mounted 8. One frame is rigidly fixed at three points on the hitch of the traction mechanism, the other has the ability to move in a transverse vertical plane without twisting relative to the first frame, due to the use of yards of cardan joints.

Installation works as follows. The working body is mounted on a strain gauge, after which its moving part is weighed. The working body is installed at the working depth or soil surface (with a sufficient length of the soil channel) and the experiment is conducted.

сил сопротивления и веса орудия. В горизонтальной плоскости угол поворота тяг φ_xy характеризует линию действия равнодействующей R_xy сил сопротивления орудия. Усилия в тягах P₁, P₂, P₃ фиксируются тензометрическими датчиками. Для рабочих органов с значительной выталкивающей силой (например, дисковые) может потребоваться дополнительное догружение балластом подвижной рамки установки.During the passage of the working body through the soil channel, the thrusts occupy a stable position, which is fixed by two sensors that measure the angles of their deviation in the longitudinally-vertical and horizontal planes. In the longitudinal-vertical plane, the angle of rotation of the rods φ _yz indicates the slope of the resulting $$R_{yz}^G$$

resistance forces and gun weights. In the horizontal plane, the angle of rotation of the rods φ _xy characterizes the line of action of the resultant force R _xy of the gun resistance forces. The forces in the rods P ₁ , P ₂ , P ₃ are recorded by strain gauges. For working bodies with significant buoyancy (for example, disk), additional ballast loading of the moving frame of the installation may be required.

The present invention gives a positive effect in agriculture and forestry by improving the quality of testing of the working bodies, which allows you to create more advanced tillage tools.

Claims (2)

1. Installation for volumetric strain gauging, including two frames, mounting brackets to the hinged system, mounting mechanism of the working body, three rods, each of which has measuring links, characterized in that the frames are connected using three parallel rods, the ends of which are fixed by cardan hinges, moreover, the arrangement of rods ensures the movement of the movable frame in the transverse vertical plane, and the use of cardan hinges avoids twisting of the movable frame of the relative but fixed, while on the measuring units transmitted compressive and tensile forces, parallel to the rods. 2. Installation according to claim 1, characterized in that to ensure increased rigidity of the system, the points of attachment of parallel rods to the frames (centers of cardan joints) are located at the vertices of isosceles triangles inscribed in the lateral faces of the parallelogram.

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