Tunnel type liquid nitrogen flash freezer

Abstract

The present application relates to a kind of quick freezing device.For reducing the liquid nitrogen overflow amount of prior art tunnel type liquid nitrogen quick freezer, the present application provides a kind of tunnel type liquid nitrogen quick freezer, including tunnel type box, transport chain is arranged in the box, multiple rows, multiple columns diffusion fan are arranged along the box top direction in the top of the box, the air outlet of fan is located in the top of the box, liquid nitrogen spray pipe is arranged in the top of the box, it is characterized in that: multiple guide plates extending to the middle of the box are arranged along the box wall direction on the two side walls in the box, one end of guide plate is fixed with the box wall, the spacing between two guide plates on the same side wall at least spans one fan;Guide plate lower edge exceeds the lower edge of fan air outlet.This quick freezer effectively reduces the diffusion amount of overflow channel formed by liquid nitrogen along the side wall of the box to input end and output end, thereby reducing the use amount of liquid nitrogen, achieves the technical effect of cost saving, environmental protection.

Description

TECHNICAL FIELD

[0001] The application relates to a quick-freezing device, in particular to a tunnel type liquid nitrogen quick-freezing machine. BACKGROUND

[0002] Since the boiling point of liquid nitrogen is -196 DEG C, the liquid nitrogen is easy to vaporize, and a large amount of heat is absorbed in the vaporization process, so that the temperature around the liquid nitrogen is sharply reduced, and therefore the liquid nitrogen is widely applied to quick-freezing production. Taking quick-frozen prepared food as an example, the liquid nitrogen quick-freezing machine is applied to quick-freezing and preparing food, and the quick-freezing effect is good, and the quick-freezing efficiency is extremely high. The most common liquid nitrogen quick-freezing machine for food quick-freezing and preparing is mainly of a tunnel type. The tunnel type liquid nitrogen quick-freezing machine is provided with a conveying belt in a box body, liquid nitrogen nozzles are arranged at the top of the box, and a plurality of rows and columns of axial flow fans are arranged on the top of the box body. When the liquid nitrogen sprayed by the liquid nitrogen nozzles is vaporized in the box, the axial flow fans force the liquid nitrogen to diffuse to the conveying belt below. In the field of the liquid nitrogen quick-freezing machine, the axial flow fan is also called a diffusion or downward pressing fan. At present, the improvement and increase of the performance of the liquid nitrogen quick-freezing machine mainly focus on reducing the loss of liquid nitrogen. The amount of liquid nitrogen consumption is mainly determined by two aspects. One is the improvement of the air path in the box body of the quick-freezing machine. For example, the patent application 2005200065275 of the applicant submitted in 2015, an improved tunnel type liquid nitrogen quick-freezing machine, the improvement of the quick-freezing machine lies in that liquid nitrogen spraying devices are arranged at the bottom of the conveying chain, and the pipe lines for conveying the liquid nitrogen to the bottom of the conveying chain are arranged in the side walls of the box, so that the upper and lower surfaces of the conveying chain can be rapidly cooled, and the frozen food damaged by the conveying chain can be rapidly and uniformly frozen. The other is that the liquid nitrogen in the box body is overflowed from the input end and the output end of the box body. The biggest loss of liquid nitrogen of the general liquid nitrogen quick-freezing machine is concentrated in the input end and the output end. When the common liquid nitrogen quick-freezing machine works, a thick layer of liquid nitrogen accumulation frost is formed at the input end and the output end. The accumulation frost is the overflow of the liquid nitrogen. The smaller the storage amount of the accumulation frost is, the less the overflow of the liquid nitrogen is, and the lower the loss of the liquid nitrogen is. For example, the patent 2014107261464 of the applicant applied in 2014, a tunnel type liquid nitrogen quick-freezing machine, the liquid nitrogen quick-freezing machine reduces the overflow of the liquid nitrogen by arranging liquid nitrogen blocking devices at the input end and the output end.

[0003] The applicant found that the installation of the down-pressing fan is generally along the tunnel direction, and the distance between the two fans is generally 1-1.5 meters. Taking a 16-meter-long liquid nitrogen quick freezer as an example, 10-16 fans are needed to be installed in each row on the top of the box, and a total of 4 or 6 rows are needed to be installed. During the rotation of the fan, the fan close to the two side walls of the box will diffuse the liquid nitrogen mist to the four directions while being pressed downward. The liquid nitrogen mist presents a rotating downward airflow, but due to the obstruction of the box wall, a rapid liquid nitrogen overflow channel is formed between the fan and the box wall. Under the action of the fan rotation, the overflow of the channel is obvious. At the same time, if the verticality of the fan shaft deviates during installation, the overflow of the channel will be more obvious. In actual production, the shaft hole of the fan installation was misaligned, resulting in a 3° deviation of the verticality of the fan shaft, which caused the liquid nitrogen overflow to increase by several times. Therefore, during manufacturing, the verticality of the fan shaft during installation must be strictly guaranteed, which increases the processing and installation cost. SUMMARY

[0004] In order to reduce the liquid nitrogen overflow of the existing tunnel type liquid nitrogen quick freezer, the box structure of the existing tunnel type liquid nitrogen quick freezer is further improved, so as to further reduce the liquid nitrogen overflow and reduce the installation requirement of the verticality of the fan shaft.

[0005] In order to achieve the above technical purpose, the technical scheme adopted by the present application is as follows: a tunnel type liquid nitrogen quick freezer, comprising a tunnel type box, a conveying chain arranged in the box, and a plurality of diffusion fans arranged in multiple rows and multiple columns on the top of the box, wherein the outlet of the fan is located on the top of the box, and a liquid nitrogen spraying pipe is arranged on the top of the box, characterized in that: a plurality of guide plates extending to the middle of the box are arranged on the two side walls of the box along the direction of the walls, one end of the guide plate is fixed to the wall, and the distance between the two guide plates on the same side wall at least spans one fan; the lower edge of the guide plate exceeds the lower edge of the fan outlet.

[0006] Further, the upper edge of the guide plate exceeds the upper edge of the fan outlet, and a gap is left between the guide plate and the top wall of the box.

[0007] Further, the lower edge of the guide plate exceeds the lower edge of the fan outlet by 5-20 cm.

[0008] Further, the guide plates on the two side walls correspond to each other, and the extension ends of the corresponding guide plates on the two side walls towards the middle of the box are connected to form an integral plate structure.

[0009] Further, the two ends of the guide plate of the integral plate structure are reversely bent towards the middle of the guide plate to form a double-layer plate structure, the bent end is welded and fixed to the middle of the guide plate, and the bent part is connected and fixed to the wall.

[0010] Further, the flow guides on the two side walls of the box are arranged staggeredly, and the extending ends of the two side flow guides pointing to the middle part of the box form a staggered structure along the direction of the box.

[0011] The present application has the advantages that: the flow guides arranged on the side walls of the box can cut off the overflow channel formed between the fan and the side walls of the box, reduce the installation requirement of the verticality of the shaft of the fan, force the atomized liquid nitrogen to diffuse to the surface of the conveying chain under the action of the fan, effectively reduce the diffusion amount of the liquid nitrogen along the overflow channel of the box to the input end and the output end, thereby reducing the use amount of the liquid nitrogen, and achieving the technical effects of cost saving and environmental protection. BRIEF DESCRIPTION OF DRAWINGS

[0012] BRIEF DESCRIPTION OF DRAWINGS Figure 1 It is a structural schematic view of the tunnel type liquid nitrogen quick freezer provided by the present application in the first embodiment.

[0013] BRIEF DESCRIPTION OF DRAWINGS Figure 2 It is a structural bottom view of the inside of the quick freezer box in the first embodiment.

[0014] BRIEF DESCRIPTION OF DRAWINGS Figure 3 It is a structural sectional view of B-B in the first embodiment. Figure 2 BRIEF DESCRIPTION OF DRAWINGS

[0015] BRIEF DESCRIPTION OF DRAWINGS Figure 4 It is a structural schematic view of the flow guide in the second embodiment. DETAILED DESCRIPTION

[0016] The tunnel type liquid nitrogen quick freezer provided by the present application will be described in detail below in combination with the drawings and embodiments.

[0017] Embodiment 1

[0018] As shown in the drawings, a tunnel type liquid nitrogen quick freezer comprises a tunnel type box 1, a conveying chain 2 arranged in the box, and multiple rows and columns of diffusion fans 3 arranged along the direction of the box at the top of the box, and the conveying chain 2 is used to convey the quick frozen materials into the box 1 to complete the quick freezing. Figure 1 As shown in the drawings, a tunnel type liquid nitrogen quick freezer comprises a tunnel type box 1, a conveying chain 2 arranged in the box, and multiple rows and columns of diffusion fans 3 arranged along the direction of the box at the top of the box, and the conveying chain 2 is used to convey the quick frozen materials into the box 1 to complete the quick freezing. Figure 2 As shown in the drawings, a tunnel type liquid nitrogen quick freezer comprises a tunnel type box 1, a conveying chain 2 arranged in the box, and multiple rows and columns of diffusion fans 3 arranged along the direction of the box at the top of the box, and the conveying chain 2 is used to convey the quick frozen materials into the box 1 to complete the quick freezing.

[0019] According to the drawings Figure 2 As shown in the drawings, when the baffle 5 is not present, there is a gap space between the fan near the side wall of the box and the box wall. When the row of fans rotates in the same direction, the gap space between the fan and the box wall will form a rapid overflow channel. Under the blowing of the fan, the liquid nitrogen in the box will quickly move to the input end and the output end along the overflow channel, thereby causing the overflow of the liquid nitrogen. This situation is particularly when the fan 3 is installed, the fan 3 is tilted in the vertical direction, and the amount of liquid nitrogen overflow under the blowing of the fan tilted wind direction will be multiplied.

[0020] As shown in the drawings Figure 2 and the drawings Figure 3 In this embodiment, a baffle 5 is added inside the box 1. The baffle 5 spans in the width direction of the box, and the two ends of the baffle 5 are respectively welded and fixed with the left and right side walls of the box. In terms of height, the lower edge of the baffle 5 is required to be 50-200mm higher than the lower edge of the fan air outlet. The lower edge of the baffle 5 cannot extend too much, otherwise the spacing between the baffle 5 and the conveying chain 2 will be too small to affect the conveying of the material. The baffle 5 exceeding the lower edge of the fan air outlet by 50-200mm can meet the requirements. After the installation of the baffle 5, the overflow channel between the fan and the side wall of the box is cut off. The rotating air blown out of the fan air outlet is weakened in the transverse blowing direction under the blockage of the baffle 5, forcing the airflow to blow downward, and the liquid nitrogen moves downward with the airflow. However, the transverse diffusion of liquid nitrogen cannot be completely eliminated, otherwise the diffusion ability of liquid nitrogen will be reduced, which will lead to longer quick-freezing time. After the blowing airflow is blown out of the fan air outlet, it moves downward under the guidance of the baffle 5. When the airflow moves beyond the lower edge of the baffle 5, the airflow will still diffuse horizontally, but the horizontal diffusion speed will be significantly slower. The liquid nitrogen diffuses to the surface of the conveying chain and the entire box interior along with the movement of the airflow.

[0021] The installation spacing between the baffles 5 can be determined according to the liquid nitrogen spray amount and the fan speed. As shown in the drawings Figure 2 In this embodiment, a baffle is installed between every two rows of fans. According to the needs, the spacing between the baffles can also be installed across multiple rows of fans or in a combined installation mode with multiple spacings.

[0022] On the other hand, in this embodiment, when the fan rotates at high speed, the pressure between the two baffles 5 will be reduced due to the rapid passage of the airflow, according to the principle of fluid mechanics. The baffles 5 will attract each other. After a long time of operation, the baffles 5 are prone to deformation. Therefore, as shown in the drawings Figure 2 In this embodiment, the two ends of the baffle 5 are reversely bent to form a double-layer plate structure at the middle part of the baffle. The bent end is welded and fixed with the middle part of the baffle, and the bent part is fixed with the box wall. The above processing increases the strength of the baffle 5 to prevent deformation due to attraction between each other.

[0023] Example 2

[0024] In this embodiment, the mounting structure of the flow guide plate 5 is further improved.

[0025] As shown in the accompanying drawings Figure 4 In this embodiment, the flow guide plate 5 adopts a broken plate structure, that is, one end of the flow guide plate 5 is welded with the side wall of the box, and the other end of the flow guide plate is suspended in the middle of the box. The flow guide plates on both sides of the box do not correspond one by one, but adopt an interleaved arrangement. The extension ends of the flow guide plates 5 on both sides of the box, which point to the middle of the box, form an interleaved structure along the direction of the box in the middle of the box.

[0026] After adopting the above mounting structure, the flow guide plate 5 can adopt a single plate structure. The overflow channel is cut off to prevent liquid nitrogen from overflowing along the side wall of the box. At the same time, the interleaved transverse channels are provided between the two flow guide plates 5 to ensure that the liquid nitrogen can also diffuse horizontally while moving downward. Since the two flow guide plates do not form a complete air duct, the pressure change between the two flow guide plates is small under the blowing of high-speed airflow, thereby reducing the strength requirement of the flow guide plate.

[0027] The mounting distance between the flow guide plates can adopt a multi-fan spanning manner, and the distance is reasonably determined according to the specific situation.

Claims

1. A tunnel-type liquid nitrogen quick-freezing machine, comprising a tunnel-type box, a transport chain disposed within the box, and diffusion fans arranged in multiple rows and columns along the box's top, with the fan outlets located at the top of the box, and a liquid nitrogen spray pipe disposed at the top of the box, characterized in that: A plurality of guide plates extending to the middle of the cabinet are arranged on the two side walls of the cabinet along the direction of the walls, one end of the guide plate is fixed to the wall, and the distance between the two guide plates on the same side wall at least spans one fan; the lower edge of the guide plate exceeds the lower edge of the fan outlet; The upper edge of the guide plate exceeds the upper edge of the fan outlet, and a distance is left between the guide plate and the top wall; The lower edge of the guide plate exceeds the lower edge of the fan outlet by 5-20 cm; The guide plates on the two side walls correspond to each other, and the extension ends of the corresponding guide plates on the two side walls to the middle of the cabinet are mutually butted to form an integral plate structure; The two ends of the guide plate of the integral plate structure are reversely bent to the middle of the guide plate to form a double-layer plate structure, the bent end is welded and fixed to the middle of the guide plate, and the bent part is connected and fixed to the wall.

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