RU2811102C1 - Contact freezing table for food products - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: table for contact freezing of food products consists of a heat-insulated body (1) equipped with a closed transport unit, which is mounted on shafts located at the inlet and outlet of the heat-insulated body, and a cooling path located inside the circuit of the closed transport unit. The cooling path consists of freezing panels tightly joined to each other with refrigerant circulating inside them, and the closed transport unit is represented by a continuous conveyor belt with an anti-adhesive coating. Moreover, the conveyor belt is designed to be in contact with the upper surfaces of the freezing panels.

EFFECT: it is ensured that food products do not freeze to the surface of the conveyor belt and its reuse.

12 cl, 5 dwg

Description

Technical field

The present invention relates to the food industry, namely to tunnel-type refrigeration devices, and can be used for pre-freezing a food product circuit for its subsequent transportation to a blast freezer.

State of the art

A quick-freezing apparatus is known, disclosed in RF patent No. 2198359 (published on February 10, 2003, IPC F25D 13/06, F25D 17/06). The known quick-freezing apparatus contains a heat-insulated chamber, air coolers, upper and lower conveyors with mesh belts. The upper conveyor belt is covered at the top and bottom with air ducts with shower nozzles, which ensures jet washing of the product with a perpendicular air flow. Air ducts along the length of the apparatus alternate with channels for air outlet.

The disadvantage of the known analogue is the long freezing time, the need to use powerful fans, as well as the drying of unpackaged products. In addition, the use of a mesh conveyor belt leads to deformation of the product surface and, as a consequence, loss of presentation.

A nitrogen tunnel apparatus is known, disclosed in patent No. 2460021 (published on March 24, 2011, IPC F25D 13/00, F25D 3/11). The known nitrogen tunnel apparatus contains a supporting frame with a heat-insulated plate, a mesh belt conveyor, a heat-insulated box, a nozzle system, a box lifting mechanism, and a control panel. The conveyor drums are built into a heat-insulated plate along the end edges of the supporting frame; the conveyor branches contain guide slides with tension rollers and support shafts along the length and are placed longitudinally at the top and bottom of the supporting frame.

The disadvantage of the known analogue is the high consumption and cost of nitrogen supplied in the form of liquefied gas. In addition, containers with liquid nitrogen are considered sources of increased danger, which imposes strict restrictions on their storage.

A device for freezing water-containing food products is known, disclosed in the Russian Federation patent for invention No. 2777110 (published 08/01/2022, IPC F25D 13/06, A23L 3/36, A23L 3/32). The known device is a thermally insulated chamber, a chain transport device, inlet and outlet transport belts, containers, a bath for liquid refrigerant represented by ethanol, a cooling system, filtration and pumping units, a fan unit, a control and monitoring unit and paired modules with electrode matrices, equipped with an electric generator fields.

The disadvantage of the known invention is the inability to pre-freeze the surface of the food product.

The following contact freezing tables are also known:

- Contact freezing table ASM TP-1500 (access mode: https://graniholoda.ru/product/stol-kontaktnoj-podmorozki, date of access: November 2023);

- Contact frost table APH TPF (access mode: https://agro-prom-holod.ru/stol-kontaktnoy-podmorozki-aph-tpf/, date of access: November 2023);

- Contact tables for freezing (access mode: https://tecnopool-r.ru/oborudovanie/zamorazhivanie/kamery-shokovoy-zamorozki-shokfroster/kontaktnye-stoly-podmorozki/, access date: November 2023).

Known contact freezing tables consist of a heat-insulated table body equipped with a polyethylene film, which is mounted on rollers that move it. The polyethylene film is in contact with the freezing plates. When a food product is placed on said polyethylene film, its bottom surface is cooled to form a thin film of ice.

Analogs do not make it possible to make the process of freezing and transporting food products continuous, which is due to the use of disposable polyethylene film. This material has low wear resistance and mechanical strength.

Disclosure of the invention

The technical problem underlying the present invention is to provide a continuous process of pre-freezing the surface of food products.

The technical result achieved by the present invention is to prevent food products from freezing to the surface of the conveyor belt and ensure its repeated use.

The technical result is achieved by the present invention, which is a table for contact freezing of food products. The claimed table for contact freezing of food products consists of a heat-insulated body equipped with a closed transport unit, which is installed on shafts located at the inlet and outlet of the specified heat-insulated body, and a cooling path located inside the contour of the specified closed transport unit. According to the invention, the cooling path consists of tightly coupled freezing panels with refrigerant circulating inside them, and the closed transport unit is represented by a continuous conveyor belt having an anti-adhesive coating, and said conveyor belt is configured to contact the upper surfaces of said freezing panels.

Additional advantages and features of the present invention are presented in the following particular embodiments.

In particular, the heat-insulated body is made on adjustable supports.

In particular, the upper part of the thermally insulated housing is equipped with movable covers.

In particular, a polymer coating is applied to the surfaces of the shafts.

In particular, one of the shafts is kinematically connected to the drive of a continuous conveyor belt.

In particular, heat-insulating curtains made of flexible polymer material are installed at the inlet and outlet of the thermally insulated body.

In particular, a continuous conveyor belt consists of a fiberglass or Kevlar base.

In particular, the anti-adhesive coating is represented by a layer of polytetrafluoroethylene (Teflon).

In particular, the table is provided with straightening rollers through which a continuous conveyor belt passes, said straightening rollers being mounted below the level of the lower surface of the refrigeration panels.

In particular, the refrigerant circulating inside the refrigeration panels is selected from the following group: hydrocarbon freons, ammonia (717), CO2 (744).

In particular, the thermally insulated housing is equipped with a liquid receiver located under the freezing panels and connected to the drain pipe.

In particular, the table has a system for adjusting and centering the belt using sensors and pneumatic actuators.

In particular, a scraper is installed in the lower part of the thermally insulated body, configured to contact the outer surface of the continuous conveyor belt.

Brief description of drawings

An embodiment of the present invention is presented with reference to the following figures:

- FIG.1 illustrates the claimed table for contact freezing of food products in a side view;

- FIG.2 illustrates the claimed table for contact freezing of food products in a top view;

- FIG.3 illustrates the claimed table for contact freezing of food products in an isometric view;

- FIG.4 illustrates a continuous conveyor belt used in the inventive table for contact freezing of food products.

- FIG. 5 illustrates a thermally insulated housing shown in section.

Description of Embodiments of the Invention

In accordance with FIGS. 1-3, the claimed table for contact freezing of food products consists of a heat-insulated housing 1, equipped with a closed transport unit and a cooling path. The thermally insulated body is mounted on supports 2, attached to the side walls of the body 1. The lower end parts of the supports 2 are equipped with adjustable lugs 3. The adjustable lugs allow you to change the height of the declared table in the range of +/-50 mm from the nominal height and rigidly fix it on the supporting surface, for example , on the floor of the production workshop. Thermally insulated housing 1 is made of stainless steel.

The upper part of the thermally insulated housing 1 is equipped with movable covers 3. In particular, the covers can be installed in longitudinal grooves made along the length of the side walls of the housing 1 in their upper part. Thus, the covers 3 can be moved along the horizontal plane of the table, providing access to the interior, in particular, for the purpose of maintenance. Covers 3 can be made of cellular polycarbonate.

The entrance of the thermally insulated housing 1, intended for loading initial food products, is equipped with a shaft 4. The output of the thermally insulated housing 1, intended for unloading frozen food products, is equipped with a shaft 5.

The closed transport unit is represented by a continuous conveyor belt 6, shown in FIG.4. The conveyor belt 6 is installed inside the housing 1 on shafts 4 and 5, installed, respectively, at its inlet and outlet. A polymer coating is applied to the surfaces of shafts 4 and 5, which serves to prevent slipping of the tape 6. Shafts 4 and 5 are mounted in bearings of the FY 30 TF type. Shaft 5 is kinematically connected to the drive 7 of the conveyor belt 6 and acts as a drive shaft. Conveyor belt 6 is made on a fiberglass or Kevlar base and has an anti-adhesive coating. In particular, the anti-adhesive coating is represented by a layer of polytetrafluoroethylene (Teflon).

The cooling path is located inside the contour of the conveyor belt 6 and consists of freezing panels 8 tightly docked to each other (shown in FIG. 5). Freezing panels 8 are made of food-grade aluminum alloy, which has a high heat transfer coefficient. Freezing panels 8 are installed at the same level, forming an essentially flat surface along the entire length of the housing 1. Inside each freezing plate 8 there is a coil-type pipe filled with liquid refrigerant. Hydrocarbon freons, ammonia (717) or CO2 (744) are used as a refrigerant. Freezing plates 8 are connected in parallel and are supplied with refrigerant from an external refrigeration system. In accordance with FIG. 5, to supply refrigerant to the freezing panels 8, an input manifold 9 is used, installed at the entrance to the freezing panel 8; to remove the refrigerant, an output manifold 10, installed at the outlet of the freezing panel 8, is used. To drain the condensate and liquid formed during the defrosting process, housing 1 is equipped with a drain pipe 11.

The conveyor belt 6 is installed inside the housing 1 with the possibility of contact with the upper surfaces of the freezing panels 8. This is ensured by the fact that the shafts 4 and 5 are installed at the same level with the upper surfaces of the freezing panels 8. In this case, the conveyor belt 6 is installed inside the housing 1 with the ability not to contact with the lower surfaces of the freezing panels 8. For this purpose, the claimed table is equipped with straightening rollers 12, 13 and 14, fixed with the possibility of rotation in the side walls of the housing 1. In this case, the straightening roller 12 is fixed below the level of the lower surface of the freezing plates 8. This ensures that the tape 6 passes about the lower surfaces of the freezing plates 8 without contacting them in the area between the shaft 4 and the roller 12. Rollers 13 and 14 are also installed below the level of the lower surface of the freezing plate 8, while the roller 14 is installed above the roller 13 to ensure smooth transfer of the tape 6 in the direction of the shaft 4. In the lower part of the housing 1 there is a scraper (not shown in the drawings), made in the form of a plate of polymer material, one of the sides of which is equipped with a cleaning pad. The scraper is installed at the level of the outer surface of the conveyor belt 6 so that the cleaning pad can contact the specified surface of the conveyor belt 6.

At the exit from housing 1 there is a sloping slide 15, which is a plate of polymer material attached to the side walls of housing 1 at an angle to its horizontal surface. The inlet and outlet openings of the housing 1 are equipped with heat-insulating curtains 16 made of flexible polymer material.

The claimed table for contact freezing works as follows.

At the entrance to the thermally insulated housing 1, food products are laid out on the conveyor belt 6. Shaft 5 perceives the force transmitted to it by drive 7, and, rotating, moves the tape 6 linearly along the upper surfaces of the freezing plates 8. Food products at the entrance to housing 1 pass through flexible heat-insulating curtains 16, bending them and falling directly inside the table. The refrigerant circulating through the pipes inside the freezing plates 8 removes heat from the tape 6, thereby cooling it. In turn, tape 6, cooled to the temperature of refrigeration plate 8, cools the lower surface of the food product in contact with it, which gradually freezes to form a thin ice crust. The resulting ice crust prevents the product from drying out during its subsequent freezing, as well as from sticking to the surface of other conveyor lines located along the product’s path in the production chain. At the exit from housing 1, food products pass through the heat-insulating curtain 16 and fall onto the sloping slide 15, rolling down it. Since tape 6 has an anti-adhesive coating, the frozen food product does not freeze to it as a result of freezing. A conveyor belt can be placed close to the slide 15, delivering the frozen food product to the spiral blast freezing apparatus. In this case, some of the moisture from the food product may fall onto the conveyor belt 6, forming ice. The resulting ice thaws as the tape passes shaft 5 and roller 12, which guides tape 6 below the level of the lower surface of the freezing plate 8. Thus, tape 6 loses direct contact with the freezing plate 8 and gradually heats up, tending to the ambient temperature. Thus, the moisture formed during the process of thawing the ice is collected and removed from the housing 1 through the drain pipe 11. Traces of the food product are cleaned with a scraper in contact with the outer surface of the belt 6, when its contaminated section passes under the freezing plates 8. After removing the ice, the conveyor belt can be can be used repeatedly and repeatedly, and the anti-adhesive coating made of Teflon gives tape 6 additional strength and wear resistance during repeated use.

For example, on pieces of fish fillet 10-15 mm thick, laid out on belt 6 at a surface temperature of belt 6 of -37°C, an ice crust is formed within 6 minutes. The length of the refrigeration tract of the table is 5600 mm, the speed of movement of the belt 6 is set to 60 mm/min. The size of the frozen crust of the product is 2-3 mm. Next, the product rolls down slide 15 onto the conveyor line and is sent to the entrance of the spiral blast freezing conveyor apparatus.

The claimed contact freezing table can be used for freezing soft, wet, sticky, semi-liquid and liquid products that could stick, drip, deform, or lose their presentation on conventional conveyor belts of refrigeration chambers. At the same time, the use of an endless conveyor belt with Teflon coating ensures its repeated use, which is not achieved on devices that use polyethylene film, which excludes repeated use, in particular, due to damage to its integrity.

At the same time, pre-freezing allows you to prevent deformation of the product by the conveyor belt and speed up freezing in the freezer. The formation of a thin ice crust on the surface of the product on the freezing table prevents the loss of moisture and nutrients.

Claims (12)

1. A table for contact freezing of food products, consisting of a heat-insulated body equipped with a closed transport unit, which is installed on shafts made at the inlet and outlet of the specified heat-insulated body, and a cooling path located inside the contour of the specified closed transport unit, characterized in that the cooling path consists of freezing panels tightly docked to each other with refrigerant circulating inside them, and the closed transport unit is represented by a continuous conveyor belt having an anti-adhesive coating, and the specified conveyor belt is installed with the possibility of contact with the upper surfaces of the refrigeration panels. 2. The table according to claim 1, characterized in that the heat-insulated body is made on adjustable supports. 3. The table according to claim 1, characterized in that the upper part of the thermally insulated body is equipped with movable covers. 4. The table according to claim 1, characterized in that a polymer coating is applied to the surface of the shafts. 5. The table according to claim 1, characterized in that one of the shafts is kinematically connected to the drive of a continuous conveyor belt. 6. The table according to claim 1, characterized in that heat-insulating curtains made of flexible polymer material are installed at the inlet and outlet of the thermally insulated body. 7. The table according to claim 1, characterized in that the continuous conveyor belt is made on a fiberglass or Kevlar base. 8. The table according to claim 1, characterized in that the anti-adhesive coating is represented by a layer of polytetrafluoroethylene (Teflon). 9. The table according to claim 1, characterized in that it is equipped with straightening rollers through which a continuous conveyor belt passes, and said straightening rollers are installed below the level of the lower surface of the refrigeration panels. 10. The table according to claim 1, characterized in that the refrigerant circulating inside the refrigeration panels is freon. 11. The table according to claim 1, characterized in that the heat-insulated body is equipped with a liquid receiver located under the freezing panels and connected to the drain pipe. 12. The table according to claim 1, characterized in that a scraper is installed in the lower part of the heat-insulated body, configured to contact the outer surface of the continuous conveyor belt.