RU169387U1 - SCREW DEVICE FOR SCREENING OF BULK MATERIALS - Google Patents

Abstract

The utility model relates to screw devices for screening bulk materials, including caked loose bulk products in agriculture, construction and other materials. The screw device contains two parallel drive shafts with blades, covering their longitudinal casing with a loading hopper, an unloading opening of the casing in the lower part with a screening sieve, with a receiving tray and an unloading branch pipe for a descent of material. Shafts with blades rotate in opposite directions, moving material from the bottom of the casing to its side walls. The depth of the discharge opening of the casing and the screener docked to it is made at the level of the longitudinal axis of the shafts. The shafts of the shafts in the loading zone of bulk material are made in the form of a band screw with serrated cutting edges, in the sifting zone in the form of a band screw, and in the zone of the outflow of material - solid screw. The sieve openings of the sieve are elongated in different two directions, corresponding to the movement of material on the surface of the sieve.

Description

The utility model relates to devices for screening bulk materials, for example, preparing for the application of caked mineral fertilizers, as well as other bulk building materials.

A well-known sifter of bulk products containing a receiving hopper with a feeding screw, a fixed cylindrical screw chamber with a cylindrical sieve, horizontal blades fixed on the screw shaft and an unloading screw of the sifted material with an outlet pipe (RU 2225267 C1, class B07B 1/18).

However, this screw device does not provide ease of maintenance, cleaning the sieve from adhering particles of bulk material, stable axial advancement of the off-grade material. This sifter is cumbersome in design.

The closest in technical essence is a screw device for cleaning loose feed (ed. Certificate No. 1484386, class B07B 1/20), comprising a housing with a loading neck, a drive shaft with screw blades with elastic elements, an unloading neck over a screening surface. These elastic elements are made in the form of a hyperbolic spiral with a bent peripheral part at an angle of 45 ° to the axis of the shaft in the direction of movement of the material, and the holes of the screening surface are oblong, located at an angle equal to the angle of inclination of the bent turns.

This screw device is compact in design, however, during the rotation of the inclined shaft of the screw, the center of gravity of the cross-section of the bulk material rotates in the direction of rotation of the shaft and simultaneously moves in its axial direction. For this reason, the screening area of the material is reduced due to its displacement on the side surface of the sieve, which reduces the performance of the screening of the material.

In addition, the possibility of a screw device for processing partially packed bulk materials, such as granular and crystalline mineral fertilizers, is limited, due to the data of the elements of the screw blades in the area of the receiving hopper and sifting.

The objective of the proposed utility model is to increase productivity and ensure the screening of packed bulk materials.

The problem is achieved in that in a screw device for screening bulk materials containing a drive shaft with screw blades, a closed casing with a loading hopper and an unloading hole in the lower part of the casing with a screening sieve, with oblong shaped holes located long side in the direction of movement of the material, the receiving tray of the screening material and the discharge outlet pipe in the end part of the casing. According to the invention, in order to increase productivity and ensure screening of packed bulk materials, the device is equipped with an additional drive shaft with screw blades mounted parallel to the existing drive shaft, while the depth of the discharge opening of the casing and the screening screen attached to it is made at the level of the longitudinal axis of the shafts, made for rotation in opposite directions to move the material from the bottom of the lower part of the housing to its side walls, and lengths s hand sieve openings disposed respectively in the directions of movement of the bulk material.

The screw device in the area of the receiving hopper screw blades are made in the form of a solid screw with a serrated cutting of the outer edges, and in the screening zone the blades are made in the form of a band screw.

In FIG. 1 shows a general view of a screw device in a side view in section, in FIG. 2 is a section AA in FIG. 1, in FIG. 3 is a section BB in FIG. 1, in FIG. 4 is a view B in FIG. one.

The screw device contains two parallel drive shafts 1 with blades, covering the shafts of a common longitudinal casing 2 with a loading hopper 3, an unloading opening of the casing in the lower part with a screening sieve 4, with a receiving tray 5 and an unloading pipe 6 for material to exit. The blades of 7 shafts in the loading zone of bulk material are made in the form of a band screw with serrated cutting edges, the blades 8 in the screening zone are made in the form of a band screw, and the blades 9 in the unloading zone of the material gathering are in the form of a solid standard screw.

The shafts 1 have opposite directions of their rotation, providing movement of the material from the bottom of the lower part of the casing to its side walls.

The depth of the discharge opening of the casing 2 and the sieving sieve 4 docked thereto is made at the level of the longitudinal axis of the shafts 1. The sieving holes 10 of the sieve 4 are made in different elongated directions at an angle of 40-45 ° corresponding to the movement of the material over the surface of the sieve.

The device operates as follows.

Bulk material, prone to caking, for example mineral fertilizers, is loaded into the receiving hopper 3, where the caked material is crushed by rotating the blades 7 of the shafts 1. Then, in the casing 2, the crushed material is intensively moved by the blades 8 of the shafts, moves along the sieve 4 towards the side their surfaces and the corresponding longitudinal shapes of the openings 10. The remaining part of the whole screen goes through the discharge pipe 6 of the casing.

By increasing the sieve area of the screening material, providing different directions of rotation of the shaft blades and the corresponding shapes of the holes of the sieves, the performance of the screw device increases.

The presented types of screws provide the possibility of using caked material in the loading zone, prevents congestion of axial movement of subsequent material and guarantees its performance.

Claims (2)

1. A screw device for screening bulk materials, containing a drive shaft with screw blades, a closed casing with a loading hopper and an unloading hole in the lower part of the casing with a screening sieve, with oblong shaped openings located long side in the direction of movement of the material, a receiving tray of screening material and a discharge outlet pipe in the end part of the casing, characterized in that, in order to increase productivity and ensure screening of packed bulk materials, the device with equipped with an additional drive shaft with helical blades mounted parallel to the existing drive shaft, while the depth of the discharge opening of the casing and the sieving screen attached to it is made at the level of the longitudinal axis of the shafts, which are rotatable in opposite directions to move the material from the bottom of the lower part of the housing to it side walls, and the long sides of the sieve openings are respectively located in the directions of movement of the bulk material. 2. The screw device according to claim 1, characterized in that in the area of the receiving hopper the helical blades are made in the form of a continuous screw with a serrated cutting of the outer edges, and in the screening zone the blades are made in the form of a band screw.

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