An alternating air supply tunnel type refrigeration device

Abstract

The present invention discloses an alternating air supply tunnel type freezing device, comprising an internal freezing tunnel and a variable speed wrap-around conveyor belt, wherein the upper and lower sides of the conveyor belt in the freezing tunnel are both provided with cold air supply ducts, air supply fans and air supply ports, and the characteristic is that: in the air supply port, the upper side is an arched lower jet air supply slit, and the lower side is an upward blowing floating air supply orifice plate, and at the same time, the upper and lower air ports are staggered forward and backward along the conveying direction to avoid airflow collision, realize alternating upper and lower air supply, and synchronous freezing. The alternating air supply tunnel type freezing device has a reasonable structure, high freezing efficiency, ensures the freezing quality of materials, and reduces the energy consumption of the equipment, and has a broad market prospect.

Description

Technical Field

[0001] The invention relates to the field of refrigeration equipment, and in particular to an alternating air supply tunnel type refrigeration device for quick freezing of aquatic products. Background Art

[0002] At present, the refrigeration equipment used for aquatic products is generally divided into cabinet type and tunnel type. Among them, the tunnel type refrigeration device belongs to the assembly line production equipment, which is suitable for the production of large quantities of frozen aquatic products and is widely used. The main components of the tunnel type refrigeration device are low-temperature heat exchangers, air duct systems, material conveying systems, electrical control systems and insulation walls. Its working method usually relies on the fan at the top of the tunnel to blow out the cold air that has been cooled by the heat exchanger, and conduct convection heat exchange with the aquatic products on the conveyor belt, so that the aquatic products can be quickly frozen.

[0003] Patent CN204648797U proposes a quick-freezing tunnel conveyor freezing device with intelligent speed regulation, which is equipped with a temperature measuring device and a frequency conversion speed regulation device; Patent CN109405398A proposes a tunnel-type double-conveyor belt quick-freezing machine with forced cooling and double-sided air distribution, which uses double conveyor belts and a centrifugal fan in the middle to quickly exchange heat and cold with the food on the mesh belt; Patent CN03823210.3C proposes an airflow-enhanced tunnel freezing equipment, and provides an impact cover for the freezing equipment to guide the ejected refrigerant through the impact plate to the food on the conveyor belt.

[0004] The existing problem is that the existing tunnel-type freezing equipment only has one-sided air supply on the upper part of the conveyor belt, which leads to uneven heat exchange between the upper and lower parts of the food, and is prone to local over-freezing and under-freezing problems. This method has a low air circulation utilization rate and a low convection heat transfer coefficient with the food, which affects the quick freezing effect and food quality. In addition, the existing tunnel-type freezing equipment does not have a return air duct, and the cold air is directly dissipated into the environment after heat exchange with the material, resulting in a partial waste of cold air. In addition, in order to ensure the quality of aquatic products, the existing tunnel-type freezing equipment has a single air supply mode, that is, high flow rate and low temperature, which will also lead to an increase in energy consumption. Summary of the invention

[0005] In order to solve the problems of local over-freezing and under-freezing of materials caused by one-sided air supply in the above-mentioned prior art, and the problem of excessive energy consumption of equipment caused by a single air supply mode, the present invention provides an alternating air supply tunnel freezing device.

[0006] The technical solution adopted by the present invention is as follows:

[0007] An alternating air supply tunnel type freezing device comprises an internal freezing tunnel, wherein a speed-adjustable wrap-around conveyor belt is installed in the freezing tunnel, wherein the two ends of the conveyor belt are respectively a material inlet and an outlet, and a temperature sensor is provided on the conveyor belt and is connected to a variable cooling amount adjustment system; cold air supply ducts, air supply fans and air supply ports are provided on the upper and lower sides of the conveyor belt in the freezing tunnel, wherein the upper side of the air supply port is a lower jet air supply slit, and the lower side is an upper floating air supply orifice plate, and at the same time, the upper and lower air outlet positions are staggered front and back along the conveying direction to avoid airflow collision, thereby realizing alternating upper and lower air supply and synchronous freezing.

[0008] The conveyor belt is a mesh belt, and a mechanical vibration device is installed between the upper and lower belts of the conveyor belt. The mechanical vibration device is in the shape of a triangular prism and is scattered on the lower side of the upper belt of the conveyor belt at intervals of 10-20 cm. When started, it can rotate continuously to make the upper belt vibrate continuously. The vibration frequency and the start time can be set to make the heat exchange of the material more uniform while avoiding adhesion.

[0009] The upper and lower ends of the freezing tunnel are each provided with a return air duct, through which the air enters the front section of the heat exchanger to form a closed cycle, thereby achieving the effect of reducing energy consumption.

[0010] The tunnel-type freezing device is provided with a variable cooling capacity adjustment system, and a temperature sensor is provided on the conveyor belt. Based on the upper and lower surface temperatures of the material, the fan speed and the surface temperature of the heat exchanger are controlled, thereby controlling the air supply parameters of the lower jet and upper blowing, including the air supply temperature and flow rate, that is, the freezing speed is increased, the evaporation temperature is reduced, and the fan speed is increased in the inlet section, so that the material passes through the ice crystal belt quickly, thereby ensuring the quality of the material; the cooling capacity required in the middle and outlet sections is reduced, the evaporation temperature can be increased, and the fan speed can be reduced, thereby reducing the waste of cold air, while reducing the energy consumption of the equipment, and further reducing the cost of quick freezing.

[0011] In the present invention, air supply ports are arranged on the upper and lower sides of the conveyor belt, which avoids the problem of partial over-freezing and under-freezing of materials caused by unilateral air supply. The positions of the upper and lower air ports are staggered front and back along the conveying direction to avoid the phenomenon of airflow collision, realize alternating air supply up and down, and achieve synchronous and uniform freezing. In addition, the upper and lower ends of the freezing tunnel are respectively provided with return air ducts, and the cold air enters the front section of the heat exchanger through the return air duct to form a closed cycle, thereby achieving the effect of reducing energy consumption. In addition, the mechanical vibration device also avoids the problem of material adhesion on the conveyor belt. The variable cooling amount adjustment system of the present invention can control the air supply temperature and flow rate based on the upper and lower surface temperatures of the material, that is, increase the freezing speed in the inlet section, reduce the evaporation temperature, increase the fan speed, and make the material pass through the ice crystal belt quickly, thereby ensuring the quality of the material; the required cooling amount in the middle and outlet sections is reduced, the evaporation temperature can be increased, and the fan speed can be reduced, thereby reducing the waste of cold air, while reducing the energy consumption of the equipment, and further reducing the cost of quick freezing. The alternating air supply tunnel type freezing device has a reasonable structure, high freezing efficiency, ensures the freezing quality of the material, and reduces the energy consumption of the equipment, and has a broad market prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a front half-section schematic diagram of an embodiment of the present invention.

[0013] Figure 2 AA cross-sectional view of the embodiment of the present invention.

[0014] Figure 3 BB is a cross-sectional view of an embodiment of the present invention.

[0015] Conveyor belt 1, material inlet 2, material outlet 3, temperature sensor measuring point 4, variable cooling amount adjustment system 5, air supply duct 6, upper air supply duct 6-1, lower air supply duct 6-2, air supply fan, air supply outlet, air supply jet slit 8-1, air supply floating hole plate 8-2, mechanical vibration device 9, return air duct, upper return air duct 10-1, lower return air duct 10-2, heat exchanger 11. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] In the embodiment, Figure 1 , Figure 2 , Figure 3 As shown, an alternating air supply tunnel type freezing device includes a built-in freezing tunnel. The material enters from the inlet 2 at one end of the speed-adjustable circular conveyor belt 1 and is discharged from the outlet 3 at the other end. Driven by the air supply fan, the cold air flows through the air supply duct 6 on the upper and lower sides of the conveyor belt 1 and flows out from the air supply port 8 to cool the material. In the air supply port, the upper side is the lower jet air supply slit 8-1, and the lower side is the upper blowing floating air supply orifice plate 8-2. The lower jet air supply slit 8-1 is located at the top of the center of the conveyor belt and is evenly distributed along the conveying direction. The jet gas flow rate is large, which accelerates the gas flow and significantly improves the refrigeration efficiency in the freezing tunnel. The upper blowing floating air supply orifice plate 8-2 is a rectangular orifice plate structure, which matches the shape of the conveyor belt 1 to ensure that the material on the conveyor belt is evenly cooled. The upper and lower air supply ports are staggered front and back along the conveying direction. Driven by the air supply fan, the upper and lower alternating air supply is realized to avoid the phenomenon of airflow collision, synchronize freezing, and effectively improve the heat exchange effect.

[0018] In the embodiment, Figure 1 As shown, the conveyor belt 1 uses a speed-adjustable conveyor mesh belt. A mechanical vibration device 9 is installed between the upper and lower belts of the conveyor belt 1. The mechanical vibration device 9 is in the shape of a triangular prism and is scattered on the lower side of the upper belt of the conveyor belt 1 at intervals of 10-20 cm. When started, it can rotate continuously to make the upper belt vibrate continuously, thereby avoiding the problem of adhesion between materials. At the same time, it also achieves the effect of enhancing heat exchange. The vibration frequency and the start time can be set manually.

[0019] In the embodiment, Figure 2, Figure 3 As shown, the freezing tunnel is provided with a return air duct, including an upper return air duct 10-1 and a lower return air duct 10-2. The air enters the front section of the heat exchanger 11 through the return air duct, and is sent into the freezing tunnel through the air supply port after being cooled by the heat exchanger, forming a closed cycle of airflow, thereby achieving the effect of reducing energy consumption. It is worth noting that since the air supply port is staggered forward and backward along the conveying direction, the lower jet and the upper blowing float each form two counterclockwise annular flow fields, avoiding interference between airflows.

[0020] In the embodiment, Figure 1 As shown, the alternating air supply tunnel freezing device is provided with a variable cooling capacity regulating system 5, that is, a plurality of temperature sensor measuring points 4 are provided on the conveyor belt 1, and the speed of the adjacent fans and the surface temperature of the heat exchanger are controlled based on the upper and lower surface temperatures of the material, thereby controlling the air supply parameters of the lower jet and the upper blowing, that is, increasing the freezing speed, lowering the evaporation temperature, and increasing the fan speed at the inlet section, so that the material can quickly pass through the ice crystal belt, thereby ensuring the quality of the material; the cooling capacity required in the middle and outlet sections is reduced, the evaporation temperature can be increased, and the fan speed can be reduced, thereby reducing the waste of cold air, while reducing the energy consumption of the equipment, and further reducing the quick freezing cost.

Claims

1. An alternating air supply tunnel type freezing device, comprising a built-in freezing tunnel, wherein a speed-adjustable circular conveyor belt (1) is installed in the freezing tunnel, characterized in that: The two ends of the conveyor belt (1) are respectively a material inlet (2) and an outlet (3), and a temperature sensor (4) is provided on the conveyor belt and is connected to a variable cooling amount regulating system (5); the upper and lower sides of the conveyor belt in the freezing tunnel are both provided with cold air supply ducts (6), air supply fans and air supply outlets, and in the air supply outlets, the upper side is a lower jet air supply slit (8-1), and the lower side is an upper floating air supply orifice plate (8-2), and at the same time, the upper and lower air outlets are staggered forward and backward along the conveying direction to avoid airflow collision, thereby realizing alternating upper and lower air supply and synchronous freezing. The conveyor belt (1) is a mesh belt. A mechanical vibration device (9) is installed between the upper and lower belts of the conveyor belt (1). The mechanical vibration device (9) is in the shape of a triangular prism and is scattered at intervals within a range of 10-20 cm on the lower side of the upper belt of the conveyor belt (1). When started, it can rotate continuously to make the upper belt vibrate continuously, turn the frozen objects evenly, and prevent them from freezing and sticking to the conveyor belt. Return air ducts are respectively arranged at the upper and lower ends of the freezing tunnel, and the air enters the front section of the heat exchanger (11) through the return air duct to form a closed air circulation.

2. The alternating air supply tunnel freezing device according to claim 1, characterized in that: The variable cooling amount regulating system (5) is connected to the temperature sensor (4) on the conveyor belt (1), and can control the fan speed and the evaporation temperature of the heat exchanger (11) based on the upper and lower surface temperatures of the material, thereby controlling the air supply flow rate and temperature of the lower jet and upper blowing.

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