RU2497345C1 - Mechanism of cleaning of grain combine harvester - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to agricultural machinery industry. The mechanism of cleaning of grain combine harvester comprises transition grate 1, the upper and lower sieve boots 2, drive shaft 3, connecting rods 6, 7 and fingers 8, 9. The upper and lower sieve boots 2 are rigidly interconnected. The drive shaft 3 has two pairs of cranks 4 and 5, located at an angle of 180°. The centers of mass of the transition grate 1 and sieve boots 2, the longitudinal axes of the drive shaft 3 and the fingers 8 and 9 of the connecting rods 6 and 7, mounting points of elastic suspension 11 to the transition grate 1, sieve boots 2 and the frame of the combine 10 are located in the same plane, which provides balancing of the mechanism of cleaning.

EFFECT: in movement of the transition grate 1 and sieve boots 2 in the opposite directions balance of not only inertial forces is provided, but the moments of these forces, which reduces the combine vibration and improves reliability of its work.

2 dwg

Description

The alleged invention relates to combine harvesters and can be used both in the manufacture of new and in the modernization of existing combines.

Known drive crank mechanism of a combine harvester, in which the connecting rods are connected to the transport board and the upper sieve mill. The lower sieve mill is connected to the upper sieve mill with the help of a two-shouldered lever and moves in the opposite direction to the upper sieve mill / 1 /.

The disadvantage of this mechanism is that the inertia forces of the transport board and the upper sieve mill are not balanced by the inertia forces of the lower sieve mill due to the design features of the drive mechanism, but are summed up and transmitted through the connecting rods to the drive shaft and to the combine frame, subjecting it to vibrations / 1 / . In addition, the distance between the upper and lower sieve mills is more than 400 mm . This leads to a moment of inertia, which is transmitted through the suspension to the frame of the combine, increasing its vibration. It is known that 70% of the overall vibration of the combine is contributed by the dynamic loads of the cleaning mechanism. After harvesting, this mechanism accounts for the largest number of failures, and the MTBF of the Don-1500B combine is 4 ... 15 hours / 2 /.

The closest technical solution to the alleged invention relates to a balanced harvester cleaning system, in which a drive shaft with a one-sided arrangement of cranks through the connecting rods is connected to the upper sieve mill and through two-arm levers with a transport board and lower sieve mill. As a result, the upper sieve mill moves in the opposite direction to the lower sieve mill and the transport board. Therefore, the common center of mass of the upper and lower sieve mills and the transport board during operation of the mechanism are at rest and the total inertia of these working bodies is zero / 3 /.

The disadvantage of this mechanism is that despite the fact that the inertia forces are balanced on the drive shaft, the combine frame and the connecting rods are affected by the total inertia of the transport board, the upper and lower sieve mills, i.e. the inertia forces on the drive shaft are not only not balanced, but also added up.

The aim of the proposed invention is the balancing of the forces and moments of inertia of the cleaning mechanism, reducing the vibration of the harvester and increasing its reliability.

This goal is achieved by the fact that the centers of mass of the transport board and sieve mills, the longitudinal axis of the drive shaft and the pins of the connecting rods, the attachment points of the elastic suspensions to the transport board, sieve mills and to the frame of the combine are located in one plane.

A comparable analysis with the prototype shows that the claimed cleaning mechanism of the combine harvester is characterized in that the centers of mass of the transport board and sieve mills, the longitudinal axis of the drive shaft and the rods of the connecting rods are located in the same plane. As a result, not only the inertia forces of the transport board and sieve mills are balanced, but also the moments of these forces. Thus, the claimed cleaning mechanism of the harvester meets the criterion of "novelty."

In addition, in the inventive cleaning mechanism of the combine harvester in the presence of moving the transport board and sieve mills in opposite directions, unlike other technical solutions in the art, elastic suspensions are introduced, the attachment points of which to the transport board, sieve mills and to the frame of the combine in a plane passing through the centers of mass of the transport board, sieve mills, the longitudinal axis of the drive shaft and the connecting rod fingers. This allows you to balance the reaction of elastic forces and moments of these forces, which allows us to conclude that the alleged invention meets the criterion of "significant differences".

The main elements of the proposed mechanism for cleaning the combine harvester are presented in the attached figures. Figure 1 shows the cleaning mechanism of the combine harvester - the main view. Figure 2 shows the cross section AA - "top view" of this mechanism. The center of mass of the transport board (ЦМ1) 1 and the center of mass of the upper and lower sieve mills rigidly interconnected (ЦМ2) 2 are located in the same plane I - I, through which the longitudinal axis of the drive shaft 3 passes, with two pairs of cranks 4 and 5, located at an angle of 180 °. The cranks 6 and 7 are put on the cranks, the fingers of which 8 and 9 are attached one to the transport 1 and the other to the sieve mills 2. The longitudinal axis of the fingers 8 and 9 are also located in plane II. The transport board 1 and the sieve mills 2 in the plane of the location of their centers of mass are attached to the frame of the combine 10 with the help of elastic suspensions 11. Fastening the suspensions 11 to the frame of the combine 10 is also made in this plane. At the end of the drive shaft is a V-belt pulley 12.

The mechanism works as follows. When the combine engine is turned on, rotation is transmitted to the pulley 12 and to the drive shaft 3. The connecting rods 6 and 7, mounted on the cranks 4 and 5 of the drive shaft 3, transform the rotational movement of the drive shaft 3 into the reciprocating movement of the transport board 1 and the upper and lower sieve mills, rigidly interconnected 2, which are attached to the frame of the combine 10 by means of elastic suspensions 11. The cranks 4 and 5 are phase shifted by an angle of 180 °. Transport board 1 and sieve mills 2 make movements in opposite directions. This achieves complete or partial (depending on the ratio of moving masses) balancing of the inertia forces of the transport board 1 by the inertia forces of the sieve mills 2. The attachment points of the suspensions 11 to the working bodies and to the frame of the combine 10 are carried out in the plane of the mass centers of the transport board 1 and sieve mills 2. This is achieved by balancing not only the forces of inertia, but also the moments of inertia of the transport board 1 and sieve mills 2, as well as the elastic forces of the suspensions.

The grain heap coming from the threshing machine and the straw walker onto the transport board 1, under the influence of vibrations, is redistributed in the layer according to the mass of components and moves to the sieve mills 2. Here it is cleaned of straw and floor under the influence of sieve and air flow vibrations. Grain material, straw and floor are sent to the appropriate containers.

Thus, to balance the forces and the moment of inertia of the cleaning mechanism, it is necessary that the centers of mass of the transport board and sieve mills, the longitudinal forces of the drive shaft and the connecting rod fingers, the points of attachment of the elastic suspensions to the transport board, sieve mill and to the frame of the combine are located in the same plane . This ensures the balancing of the cleaning mechanism, reducing the vibration of the combine, increasing its reliability, reducing crop losses during harvesting.

To make our reasoning more convincing, imagine a plane that flies 50 years (a combine harvester has a life of 8 years with an annual load of 300 ... .400 hours), in which the resultant moving forces and resistance forces do not pass through the center of mass and the main axis of inertia of the aircraft. A catastrophe will occur immediately. Here in this mode, combine harvesters work.

Literature

1. Morozov A.F. Combine Harvesters. Album. M .: Agropromizdat, 1991 .-- 208 p.

2. Lapshin P.N. Combine harvesters: Durability, vibration resistance, reliability. Kurgan: KSAA, 2009 .-- 133 p.

3. Litvinov A.I., Meshcheryakov I.K., Kurach A.I. Balanced cleaning of a combine harvester / Tractors and agricultural machinery - 1988. - No. 3. - S. 19-21.

Claims (1)

The mechanism for cleaning the combine harvester, including a transport board, upper and lower sieve mills, rigidly interconnected, a drive shaft with two pairs of cranks located at an angle of 180 °, rods and fingers, characterized in that the centers of mass of the transport board and sieve mills, longitudinal the axis of the drive shaft and the connecting rod fingers, the mounting points of the elastic suspensions to the transport board, sieve mills and to the frame of the combine are located in the same plane.

Images