RU2450924C1 - Extruder with mandrel - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to extrusion equipment used in food industry and production of extruded mixed fodder. Proposed extruder comprises bed, working chamber, screw with drive, female die and mandrel with drive. Note here that screw taper surface has coils representing extension of screw MAIN coils. Mandrel consists of tapered and cylindrical parts. Shaped vanes arranged along screw path are fitted on mandrel tapered surface. Note here that every shaped vane has stepped shape. Blades are arranged on mandrel cylindrical part. Female die inner tapered surface is provided with stepped cylindrical cutouts matching in sizes with stepped ledges of shaped vanes. Mandrel tapered part end is furnished with screw drill with its tapered part centered in screw taper hole.

EFFECT: higher quality of finished product.

3 dwg

Description

The invention relates to equipment for the production of extruded protein texture from vegetable raw materials in the food industry, as well as for the extrusion processing of animal feed in feed mills.

The closest in technical essence and the achieved effect is an extruder [RF patent No. 2299124, IPC В29С 47/12, В29В 9/06. Extruder / E.G. Okulich-Kazarin, A.N. Ostrikov, A.S. Rudometkin, M.A. Glukhov (RF). - 2005135573/12; declared 11/16/2005; publ. 05/20/2007, bull. No. 14], including a housing, a screw with a rotation drive and a forming head with a mouthpiece and a conical mandrel. The conical mandrel is equipped with a shaft and is made of prefabricated in two parts. Each of the mandrel parts is configured to control the direction and speed of rotation using coaxial shafts and a gearbox. One of the shafts is solid and located in another hollow shaft. The mouthpiece has the ability to reciprocate along the axis of the extruder using a rack and pinion mechanism. The slots are on the inside of the mouthpiece. They are guides rigidly connected to the surface of the output end of the extruder body. The shape of the guides on the extruder body follows the shape of the slots on the mouthpiece so that the guides enter into the slotted grooves of the mouthpiece. The rack gear gear rigidly fixed to its shaft is engaged with a rack rigidly attached to the mouthpiece. The taper angles of the inner part of the mouthpiece and the conical mandrel are selected so that the gap between them has the shape of a conical annular channel. The outer surface of the last part of the mandrel and the inner surface of the conical part of the mouthpiece are knurled to obtain the product of the desired shape.

A disadvantage of the known extruder design is the difficulty in maintaining the physicochemical transformations of the main components, as well as the inability to grind the product to the molecular level necessary for better absorption by the body of the components (proteins, starch, fats, enzymes, etc.).

An object of the invention is to develop a design of an extruder with a mandrel, which allows grinding operations to be carried out to a molecular level and to provide improved quality of the finished product due to a deeper thermomechanical effect.

The object of the invention is achieved in that in an extruder with a mandrel, including a bed, a working chamber, an auger with a drive, a die, a mandrel with a drive, it is new that the turns are made on the surface of the conical part of the auger as a continuation of the main turns of the auger, the mandrel consists of the conical and cylindrical parts, on the conical surface of the mandrel mounted curly blades made along a helical path, with each curved blade has a stepped shape, on the cylindrical part of the mandrel there are knives, on the inner usnoy matrix surface machined stepped cylindrical recesses corresponding in size stepwise protrusions curved vanes on the end of the conical part of the mandrel is mounted screw auger, its conical part which is centered by means of the screw holes in the cone.

Figure 1 shows a front view of the extruder with a mandrel, figure 2 is a three-dimensional image of the extruder with a mandrel, figure 3 is a three-dimensional image of the mandrel with a drill.

The extruder with a mandrel consists of a working chamber 8, a loading nozzle 15, a screw 9, a mouthpiece 16 and a matrix 2 (figures 1 and 2).

The screw 9 is driven into rotation by the electric motor 10 using a gearbox 12, elastic couplings 11 and 13 and the bearing assembly 14. The speed of the screw 9 can be adjusted using a thyristor frequency controller on the electric motor 10.

On the conical surface of the screw 9, turns 3 are machined, which are a continuation of the main turns of the screw. They prevent product burning in the matrix zone.

An air conditioning device 1 is installed on the working chamber 8, which allows maintaining the necessary temperature of the chamber 8, while creating optimal extruder operation parameters.

On the conical surface of the mandrel there are curly blades 5 (Fig.3), made along a helical path. On each curved blade 5 made stepped protrusions. On the inner conical surface of the matrix 2, stepwise cylindrical cutouts are machined, corresponding in size to the stepwise protrusions of the figured blades 5.

At the end of the conical part of the mandrel 6, a helical drill 4 is installed, which enters the hole on the conical part of the screw 9, thereby ensuring the centering of the screw 9 and the drill 4.

On the cylindrical part of the mandrel 6 there are knives 7, providing grinding texture. The crushed texturate enters the pipe 22 to divert the finished product.

Dorn 6 is driven into rotation by a gear motor 20, providing smooth control of the rotation speed of the mandrel 6. Screw drive 9 (electric motor 10, elastic couplings 11 and 13, gear 12 and bearing assembly 14), chamber 8 and mandrel drive 6 (gear motor 20 and the bearing assembly 19) are mounted on the frame 21.

The mandrel 6 and the matrix 2 are located in the chamber 18, which performs both the function of collecting the finished product and removing it through the pipe 22, and the protection function from the rapidly rotating mandrel 6.

Evaporated water vapor is removed from the exhaust diffuser 17 of the chamber 18, which is formed due to explosive evaporation of moisture from the texture.

An extruder with a mandrel operates as follows.

The motor 10 is turned on, which, with the help of the gearbox 12, the elastic couplings 11 and 13 and the bearing assembly 14, drives the screw 9. In this case, the required speed of the screw 9 is set using the thyristor control of the electric motor 10. At the same time, the gear motor 20 is turned on, which drives the rotation of the mandrel 6 using the bearing assembly 19.

The nutritional value of any food product is determined by its physiological calorie content, which, in turn, is associated with the digestibility of proteins, fats, carbohydrates. Extrusion technology allows you to quantitatively and qualitatively change the structure, composition and nutritional value of the protein-starch complex.

The initial product from the loading pipe 15 enters the loading zone of the screw channel of the screw 9 and is carried away by it due to the difference in the friction forces between the product and the walls of the housing 8 and the screw channel of the screw 9, while gradually being compacted.

In the mixing zone, the product is mixed and moved by turns of the screw 9 in order to obtain a homogeneous mixture. Further, in the homogenization zone, compaction and grinding of the product occurs, which causes the formation of an extrudate melt.

In the homogenization zone, the product finally passes from the solid phase to the viscoplastic; here, melting occurs as a result of the conversion of the mechanical energy of the working bodies of the extruder into thermal energy and due to internal friction in the product itself under the autogenous mode of operation of the extruder.

Throughout the entire movement of the product, the temperature regime is regulated by the conditioning device 1, which is a hollow pipe into which a coolant with a given temperature is supplied.

Under the influence of factors such as pressure and temperature, proteins undergo denaturation, which is an intramolecular phenomenon characterized by a physical rearrangement of internal bonds. In this case, there is a violation of the ordering of the internal structure of the molecule, quantitatively determined by a change in the physicochemical properties of proteins (solubility, ability to hydrate, viscosity of solutions, resistance to enzymes, biological activity, etc.) [Ostrikov AN Extrusion in food technology. [Text] / A.N. Ostrikov, O.V. Abramov, A.S. Rudometkin. - St. Petersburg: GIORD, 2004. - 288 p.].

The processed product located in the matrix zone of the extruder is subjected to mechanical mixing of the coils 3 and drill 4, which eliminates the possibility of the formation of a "dead zone", i.e. product sticking to the inner walls of the matrix 2. In the gap between the matrix 2 and the mandrel 6, the product is subjected to intense mechanical stress with the help of curly blades 5. The stepped protrusions of the curved blades 5, rotating in coaxial, corresponding to the size of the stepped cylindrical cuts on the inner conical surface of the matrix 2, affect the microstructure of the outgoing texturate by smearing it along the walls of the matrix. In this case, the chain of protein molecules breaks into smaller components (polypeptides and peptides).

When leaving the matrix 2, the texturate is intensively crushed by the knives 7 installed on the cylindrical part of the mandrel. After grinding, the product enters the chamber 18, from which crushed texturate is discharged through the pipe 22. At the same time, evaporated water vapor is discharged through the exhaust diffuser 17 of the chamber 18, which is formed due to explosive evaporation of moisture from the texture.

Thus, the use of the invention allows:

- to ensure the stable operation of the extruder through the use of turns on the conical part of the screw and drill in the mandrel;

- to improve the quality of the obtained protein texture by regulating the thermomechanical effects on the processed product;

- to provide the necessary depth of physico-chemical transformations of the components of the processed product by regulating the heat supply and the mechanical effect of the curly blades 5.

Claims (1)

An extruder with a mandrel containing a bed, a working chamber, an auger with a drive, a die and a mandrel with a drive, characterized in that the turns are made on the surface of the conical part of the screw as a continuation of the main turns of the screw, the mandrel consists of a conical and cylindrical part, and the mandrel is installed on the conical surface figured blades made along a helical path, each figured blade having a stepped shape, there are knives on the cylindrical part of the mandrel, stepwise cylindrical notches are machined on the inner conical surface of the matrix zy corresponding in size stepwise protrusions curved vanes on the end of the conical part of the mandrel is mounted screw auger, its conical part which is centered by means of the screw holes in the cone.

Images