WO2016048124A1 - The concave for threshing machines of cereal crops - Google Patents

Abstract

The invention belongs to agricultural machinery. The aim of the invention: to ensure a qualitative, complete and efficient threshing process and to improve the conditions of the threshing process. In order to achieve the aim of the invention, the plane of the concave (2) in the threshing machine is incurved in such a way that the gap (3) between the threshing drum (1) and concave remains evenly decreasing over the entire length of the concave, from its beginning to its end and is directly proportional to the drum rotation angle φ.

Description

THE CONCAVE FOR THRESHING MACHINES OF CEREAL CROPS

The invention belongs to agricultural machinery, namely, to mechanisms of threshing machines of cereal crops.

It is known in the threshing machine described in the RU patent No. 21 19280, TPKK: A 01 F 7/06, A 01 F 29/00, published in 1998), a cancellated concave with a cylindrical part with cutting blades, consisting of the upper and lower parts and the mechanism that enables to change the size of the even gap/distance between the drum and concave.

The known technical solution does not ensure the complete threshing of agricultural plants - cereal crops.

The aim of the invention: to ensure a qualitative, complete and efficient threshing process and to improve the conditions of the threshing process.

In order to achieve the aim of the invention, the plane of the concave in the threshing machine is incurved in such a way that the gap between the threshing drum and concave remains evenly decreasing over the entire length of the concave, from its beginning to its end and is directly proportional to the drum rotation angle of the threshing machine. Besides, the profile of the incurved plane of the concave is determined by performing calculations according to the following formulas:

Rpb(q>)=Rb+A(0)+k((p - φ(0) ), where Rpb - the length of OA segment Rb radius of the drum

Δ(0) difference between Rb and Rpb

K the coefficient of variation of the concave plane,

which determines the change of the gap between the drum and concave for the angle measurement unit

φ - the rotation angle of the drum , φ(0), when Δ(0) k=A( φ)-Δ(0):φ,

Xpb(q>)=Rpb((p)-cos((p), kai 0<φ<2 rad

Ypb(9)-Rpb((p)-sin(q>), kai 0<φ<2 rad,

where X, Y the coordinates of the concave profile points.

The invention is illustrated by the diagram (see Fig. 1), where 1 - the drum of the threshing machine, 2 - the profile of the incurved plane of the concave of the threshing machine, 3 - the gap between the drum and concave.

The coordinate system (X; Y) of the drawing schematically illustrates the drum of the threshing machine 1 , the profile of the concave 2, which envelopes the drum, and the gap between them 3. For the threshing process to be qualitative and complete, it is important to determine the profile of the incurved plate of the concave and at the same time the incurve of the plate, so that there forms an optimal gap which determines threshing of cereal crops. It is known that when the gap between the drum and concave is the same, and the profile of the concave plate is a circle, the threshing of cereal crops is not complete. Therefore, tests were carried out and calculations according to the formulas given below were done, for the determination of the profile of the concave 2, in respect to the rotation of the axis of the drum and its rotation angle φ. It was found out that the gap 3, between the drum and concave has to be evenly decreasing from the beginning of the drum A to its end B, and directly proportional to the drum rotation angle φ.

Rpb(cp)=Rb+A(0)+k(q> - φ(0))

k=A( φ)-Δ(0):φ

Xpb((p)=Rpb((p)-cos((p), when 0<φ<2 rad

Ypb((p)=Rpb((p)-sin((p), when 0<φ<2 rad

From this follows a conclusion that the profile of the plate of the concave should not be circular and the points of the profile of the concave should not be in the same distance from the drum rotation axis.

Since cereal crops differ in their size, for the threshing process to be complete, qualitative and without losses, in each specific case calculations are performed according to the given formulas.

The presented technical solution creates a possibility to ensure qualitative and complete threshing of cereal crops, which prevents losses and costs during the harvest time.

Claims

CLAIM OF INVENTION

1. The concave for threshing machines of cereal crops consisting of the incurved plate and threshing elements, characterised in that the plate of the concave is curved so that the gap is formed between the threshing drum and concave which remains evenly decreasing over the entire length of the concave, from its beginning to its end and is directly proportional to the drum rotation angle φ of the threshing machine.

2. The concave for threshing machines of cereal crops according to the claim 1 , characterised in that the profile of the incurved plate of the concave is determined by performing calculations according to the following formulas:

Rpb(q>)=Rb+A(0)+k((p - φ(0)), where Rpb - the length of OA segment

Rb - radius of the drum

Δ(0) - difference between Rb and Rpb

k - the coefficient of variation of the concave plane,

which determines the change of the gap between the drum and concave for the angle measurement unit

φ - the rotation angle of the drum, φ(0), when Δ(0)

k=A( φ)-Δ(0):φ,

Xpb(q>)=Rpb((p) cos((p), when 0<φ<2 rad

Ypb((p)=Rpb((p)-sin((p), when 0<φ<2 rad,

where X, Y the coordinates of the concave profile points.