The present invention relates to mechanical engineering, more particularly relates to mixing devices and can be used in building industry, agriculture and other fields.

According to the known concrete, mixing drum having an opening at one end for receiving and discharge of concrete therefrom and at the other end means for engaging a. drive assembly so as to rotate the drum for mixing or discharging concrete. This drum is manufactured from at least one inner mould and at least one opposing outer mould, wherein the drum includes integrally attached vanes which outstand from the internal surface of the drum forming an archimedian spiral disposed such that when the drum is rotated in a first direction, the concrete contents are mixed and when the drum is rotated in a second direction the contents are discharges from said drum [1 ]. Another known concrete mixer comprises a frame, struts, a mixing trough, a stirrup, a driving assembly. The invention is useful for concrete mixer capable of being mounted and dismounted [2].

There are a variety of mixing devices disclosed in the prior vehicle mounted as well as fixed mixers.

They suffer from a number of disadvantages relating to their cost of manufacture, working life, wear characteristics and so on. Typically, the contents is mixed with auxiliary attachment as interna] vanes, mixing blades, etc. The mixed contents is discharged under tilting the drum. No perfect discharging is possible as well as treating is complicated.

The advantages of the present invention are efficiency, easy handling, provided safety, wide application spectrum. Whereas in the case of known mixer devices for mixing of for example 2 m ^J content the appropriate capacity is on average 100 kilowatt, according to the proposed invention is sufficient only 7 kw. The known mixer devices have to be discharged and cleaned every day (after every shift). The cleaning process is labour-intensive and may be lethal by recklessness. The mixer according to the invention is very easy to clean. The cleaning results from discharging of drum. The present invention will now be described with reference to the accompanying figures 1 , 2 and 3.

Figure 1 shows a general view of the closed mixer device. Figure 2 shows a general view of the opened mixer device. Figure 3 shows a side view of the mixer device.

The mixer device comprises a vertical stand 1 and cylindrical body (drum) 2. The stand comprises a fixed part, where the drum is placed and moving part, where the door 3 is placed. The stand has on the inside rollers 4 for rotation of drum. A gearing 5 is provided around the drum, which is rotated by a gear unit 6. The drum having a bunker 7 at one end for receiving contents and discharge bunker 8 on the another end. The door of the drum is movable placed on a roller railing 9. The opening and closing of the door is provided by the roller hydraulic mounting 10. The drum discharges by opening the door. The door of the drum has an opening for water and/or air-feeding under pressure of 4-8 atm in the opposite direction of drum rotation for the purpose of wetting the contents, promotion of mixing process and cleaning of the drum. In order to increase the wearing capacity of the drum it is covered with a plastic from inside, for example, a rubber layer 12.

The operation is fully-automatic and computer controlled. The content is incoming through the receiving bunker 7 to the drum 2, which rotates for example clockwise by means of the gear unit 6 and water and/or air is feeding the opposite direction alternately if necessary, making possible to mix any material. The mixed content discharges in the discharge bunker 8 by opening the door. The door slides along the roller railing 9 by means of a hydraulic rod 10. After discharging the door closes automatically. Discharging and cleaning of the drum is carried out simultaneously. Thus it is not necessary to enter the drum by any staff.

The present mixer can be used in stationary state, as well as vehicle mounted. The drum capacity is 0,5 - 12 m ^J . The use of mixer device according to the present invention is mainly prefered for mixing of semidry materials, for example for block manufacturing. Whereas by mixing said materials by means of known mixer devices the obtained product is of poor quality (puddled, caked), the mass obtained using mixer device according to the present invention is souffle and the blocks light in weight.

[1 ] GE P 2007 4200 B (PCT/AU2003/000664)

[2] PCT/FR1997/001532