SU757214A1 - Apparatus for pneumatic cleating - Google Patents

Description

The invention relates to the field of agricultural engineering, in particular to machines for cleaning'and sorting of seeds in stationary conditions, and in relation to a combine harvester.

A device for cleaning grain, which includes a fan with discharge pipe, expansion chamber C] is known.

The disadvantage of the known device is the low productivity and low quality of grain cleaning.

The closest technical solution for the function performed and the result achieved is pneumatic cleaning, which includes a cylindrical body, a loading device, a suction confuser connected to the throat of the suction fan, a 'blower fan connected by an air duct to the body, a conical reflector screen located at the bottom enclosures (2).

A disadvantage of the known air cleaning is that the material to be divided is affected by

stuffy stream passing through the neck for removal of grain and into the gap Between the body and the tapered screen reflector. In addition, in the zone

5 of the separation of the material, only the air flows affect the heap of grain and the separation takes place according to one sign, i.e., due to the aerodynamic properties of the particles. Reflector blades mounted on the housing, fingers and other devices improve the separation of the material and its preparation for sorting, but they are not directly involved in the material separation process.

The purpose of the invention is to increase the efficiency of the separation of the grain heap.

20 This goal is achieved due to the fact that the conical screen-reflector is made in the form of a spiral, and the spiral is made of elastic material, and also due to the fact

25 that in the lower part of the helix fingers of variable cross section are made, larger in size at the base and placed

in such a way that the distance between the fingers decreases along the

30 movement of the material.

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FIG. 1 shows a diagram of a device for pneumatic cleaning; in fig. 2 - top view of the tapered screen? in fig. 3 is a view of a helix in axonometry,

The device for pneumatic cleaning consists of a cylindrical body 1, inside of which there is a confuser 2 connected to the neck of the suction fan 3, a pressure fan 4 which is connected by an air duct 5 tangentially to the cleaning body 1, and a power supply 6 is installed on the air duct.

Under the lower edge of the housing 1 there is a screen-reflector 7, made in the form of a spiral, in the lower part of which fingers 8 are made.

To regulate the gaps between the turns of the spiral, the spiral can twist in the guides (not shown in the drawings) or contract, so the spiral is made of an elastic material.

The fingers 3 can be made of variable cross-section, and with a large cross-section at the base, which allows to maintain a constant gap between the fingers when they converge to the center of the screen-reflector to prevent particles from jamming between the fingers.

Device for pneumatic cleaning works as follows. The material from the feeding device 6 is pumped by the blower fan 4 along the duct 5 tangentially into the cylindrical body 1, where the material is unwound and due to centrifugal forces the material is separated, i.e. the grain is pressed against the wall of the body, and the straw impurities are located above the grain.

When going from the case to the screen-reflector, a heap is blown by the air flow passing into the gap between the lower edge of the case and the turn of the spiral-screen of the reflector, some of the straw impurities are sucked off by the fan 3 and out of the cleaning limits. The material arriving at the screen protector is continuously blown by the air flow, while large impurities are removed by the grate to the zone of greatest impact of the air flow and are sucked off by the fan 3, through the confuser 2.

Grain from the screen-reflector comes down to the receiving tank.

Claims (3)

Claim 1. A device for pneumatic cleaning, which includes a cylindrical case, a loading device, suction confuser connected to the throat of the suction fan, a pressure fan connected by an air duct to the case, a conical reflector screen located in the lower part of the case, characterized in that in order to increase the efficiency of grain heap separation, the tapered reflector screen is designed as a spiral. 2. Device pop. 1, characterized in that the spiral is made of elastic material. 3. The device according to PP. 1 and 2, characterized in that in the lower part of the helix there are fingers of variable cross section, larger in size at the base and placed in such a way that the distance between the fingers decreases as the material moves.