Ice mold heat exchanger and method of manufacturing the same

Abstract

An ice mold heat exchanger and a manufacturing method thereof, relate to the field of special heat exchanger manufacturing, comprising a base plate, a fin, a flow channel plate, a protective cover, a heat insulation material, a heat medium inlet pipe and an outlet pipe. The base plate and the fin on the front side of the base plate enclose an ice mold, which is a slanting prism lattice structure array with one side open and uniformly inclined to one side. The base plate and the flow channel plate with continuous fold line grooves on the back side of the base plate are welded to form a heat medium flow channel. The flow channel is connected with the heat medium inlet pipe and the outlet pipe at both ends respectively. The back side of the flow channel plate is provided with a protective cover, the peripheral edge of the protective cover is closed and connected with the periphery of the base plate, and the cavity between the flow channel plate and the protective cover is filled with a heat insulation material. The fold line flow channel replaces the fold line circular pipe, the heat exchange area is improved by an order of magnitude, the heat transfer link is reduced, the heat insulation material blocks the heat leakage on the back side of the heat medium flow channel, the single side heat exchange is realized, the heat offset is eliminated, the system energy efficiency is improved, the surface of the protective cover is smooth and easy to clean, and the health protection of block ice production is facilitated.

Description

Technical Field

[0001] This invention relates to the field of special heat exchanger technology, and in particular to an ice mold heat exchanger and its manufacturing method. Background Technology

[0002] Currently, the main types of indirect heat exchangers can be broadly classified according to their structural characteristics into shell-and-tube heat exchangers, tube-and-shell heat exchangers, cross-flow heat exchangers, plate heat exchangers, and spiral plate heat exchangers. Improving the compactness and heat transfer area density of heat exchangers, and enhancing the stability of their structure and performance, are important directions for heat exchanger development. Examples include reducing pipe diameter, adopting plate structures, using various ribbed surfaces, and employing wire mesh materials. In practical engineering applications, the design and manufacture of heat exchangers must also consider a series of issues such as flow resistance, heat exchange surface structure and contamination, and manufacturing costs.

[0003] Common ice mold heat exchangers for ice making typically employ a structure combining circular or elliptical cross-section copper tubes with finned ice molds. Specifically, a substrate serves as the basic heat transfer channel and structural support, while the copper tubes act as flow channels for the heat medium (such as refrigerant), arranged in a zigzag pattern on one side of the substrate. The ice mold, formed by the fins and substrate, is positioned on the other side. The heat medium within the copper tubes exchanges heat with the water in the finned ice mold through the tube walls and substrate, causing the water to condense into ice within the finned ice mold. This structure has a mature manufacturing process and is widely used in existing ice-making equipment. However, the aforementioned traditional ice mold heat exchanger structure has the following drawbacks:

[0004] First, the heat exchange area is insufficient. The linear contact area between the copper tube and the substrate is very limited. The heat medium mainly transfers heat through the copper tube wall and the contact line between the tube wall and the substrate. The effective heat exchange area between the water or ice on the fin side and the heat medium in the copper tube is very limited, resulting in low heat exchange efficiency, slow ice-making speed, and high system energy consumption.

[0005] Secondly, heat loss is significant. The copper tubes are positioned on one side of the substrate, with most of their walls directly exposed to the ice-forming environment. When the heat transfer medium flows within the copper tubes, only a small portion of the heat transfer occurs through the connection between the copper tubes and the substrate to the fins. The majority of the heat is lost through the exposed tube walls into the ice-forming environment, resulting in substantial heat loss. This leads to heat cancellation during the ice-forming process, significantly reducing heat exchange efficiency, slowing down water temperature reduction and ice formation, thereby decreasing the system's cooling efficiency and increasing operating costs.

[0006] Third, performance deteriorates rapidly. The connection between the ice mold fins, copper tubes and the substrate is made by brazing. During the ice-making process, the temperature gradient is large and the corresponding thermal stress is large. Frequent switching between hot and cold directions is required. The ice removal process of block ice production is subject to vibration and impact. The brazed connection points are prone to loosening, which leads to a significant increase in the contact thermal resistance between the copper tube and the substrate, and between the substrate and the fins. The heat exchanger performance deteriorates rapidly and causes uneven heat flux density in different parts of the heat exchanger. The ice block formation rate of each ice grid of the ice mold is uneven, and the shape and size of the ice blocks are even irregular.

[0007] Fourth, poor hygiene. Copper pipes are exposed in the ice-making environment, and dirt can easily accumulate at the joints between the copper pipes and the substrate. Furthermore, the uneven back of the substrate and the narrow gaps between the pipes make cleaning difficult, which in turn negatively impacts the hygiene and safety of the ice. Summary of the Invention

[0008] The purpose of this invention is to provide an ice mold heat exchanger and its manufacturing method, which is fundamentally different in structure from various types of indirect heat exchangers in the general sense. It overcomes the defects of existing ice mold heat exchangers, such as insufficient heat exchange area, large heat leakage loss, rapid performance degradation, large offset of block ice generation heat, easy accumulation of dirt, and low system efficiency. In this way, it improves the heat exchanger's heat exchange performance, reduces system energy consumption, improves the sanitary conditions for block ice generation, and improves ice production efficiency.

[0009] An ice mold heat exchanger includes a base plate, an ice mold, a heat medium channel, a protective cover, a heat insulation material, and a heat medium inlet pipe and a heat medium outlet pipe. The ice mold and the heat medium channel are respectively disposed on both sides of the base plate, the protective cover is disposed on the back side of the heat medium channel, and the heat insulation material is disposed in the cavity between the heat medium channel and the protective cover. The two ends of the heat medium channel are respectively connected to the heat medium inlet pipe and the heat medium outlet pipe. The water or ice in the ice mold and the heat medium in the heat medium channel exchange heat. The heat insulation material is used to limit the heat medium in the heat medium channel to transfer heat unidirectionally towards the ice mold side and block heat leakage in the direction of the back side of the heat medium channel.

[0010] The ice mold includes multiple transverse fins and longitudinal fins arranged on the front side of the substrate, the transverse fins and longitudinal fins forming multiple ice molds with one side open and arranged in a matrix with the substrate.

[0011] The longitudinal fins are arranged along the longitudinal direction and vertically connected to the substrate, and the transverse fins are arranged along the transverse direction and uniformly inclined to the same side at a certain angle and connected to the substrate, so that the opening of the ice mold is inclined downward.

[0012] The tilt angle of the transverse fins is 5° to 15°.

[0013] The heat medium flow channel includes a substrate and a flow channel plate fixedly connected to the back side of the substrate. The inner side of the flow channel plate is provided with a continuous zigzag groove, and the zigzag groove and the back side of the substrate form a zigzag heat medium flow channel. The water or ice in the ice mold exchanges heat with the heat medium in the heat medium flow channel.

[0014] The zigzag groove on the inner side of the flow channel plate is formed by stamping. The flow channel plate and the substrate are connected by welding at the edge line and the dividing line of the zigzag groove to form the zigzag heat medium flow channel. The periphery of the flow channel plate and the substrate are sealed by welding to form a sealing line. The heat medium in the heat medium flow channel covers the entire back heat transfer area of ​​the substrate through the heat transfer area of ​​the substrate.

[0015] The protective cover is an open box-shaped structure with a rectangular flat plate with folded edges on all four sides. Its folded edges are closed and connected to the periphery of the substrate. The heat insulation material is filled in the cavity formed between the flow channel plate and the protective cover.

[0016] The heat medium inlet pipe is connected to the inlet of the heat medium flow channel and extends to the outside through the side fold of the protective cover; the heat medium outlet pipe is connected to the outlet of the heat medium flow channel and extends to the outside through the side fold of the protective cover.

[0017] In addition, the present invention also provides a method for manufacturing the above-mentioned ice mold heat exchanger, which includes the following steps:

[0018] S1. Make ice molds by welding multiple longitudinal fins and multiple transverse fins to the front side of the substrate in a crisscross pattern. The longitudinal fins are perpendicular to the substrate, and the transverse fins are uniformly welded to the substrate at a certain angle to the same side, forming multiple ice molds with one open side and arranged in a matrix.

[0019] S2. Make the flow channel plate. Take a metal plate and punch out continuous zigzag grooves on its inner side by stamping.

[0020] S3. Through holes are opened at both ends of the zigzag groove, and a heat medium inlet pipe and a heat medium outlet pipe are welded to the through holes, so that the heat medium inlet pipe and the heat medium outlet pipe are connected to the interior of the zigzag groove.

[0021] S4. The flow channel plate is attached to the back side of the substrate with its inner side facing the back side of the substrate, so that the outer contour of the flow channel plate matches the outer contour of the substrate. Then, the peripheral contact edge of the flow channel plate and the substrate is sealed and connected by welding.

[0022] S5. Along the edge line and dividing line of the zigzag groove of the flow channel plate, the flow channel plate and the substrate are pressure welded and fixed to form a welding line, so that a closed zigzag flow channel is formed between the zigzag groove and the back side of the substrate.

[0023] S6. Two through holes or notches are made on the side fold of the protective cover for the heat medium inlet pipe and the heat medium outlet pipe to pass through. The heat medium inlet pipe and the heat medium outlet pipe are passed through the corresponding through holes or notches respectively. Then the protective cover is fastened to the back side of the flow channel plate and sealed and connected to the periphery of the substrate.

[0024] S7. Filling with heat insulation material: Inject polyurethane foam raw material into the cavity between the back side of the flow channel plate and the protective cover. The polyurethane foam raw material foams and solidifies in the closed cavity inside the protective cover to form heat insulation material filling the space between the flow channel plate and the protective cover; or, before fastening the protective cover to the back side of the flow channel plate, place a rectangular flat solid heat insulation material of a predetermined size inside the protective cover, and then fasten the protective cover to the back side of the flow channel plate and seal it with the periphery of the substrate.

[0025] S8. The protective cover and the substrate can be connected by welding, riveting or bolting. The connection can be sealed with a gasket that meets the hygiene requirements for ice making or sealed with sealant.

[0026] Preferably, in step S5, the flow channel plate and the substrate are intermittently welded using a pressure welding process along the edge line and the dividing line of the zigzag groove.

[0027] More preferably, in step S7, a rectangular flat solid heat insulation material is placed inside the protective cover, and then the protective cover is fastened to the back side of the flow channel plate and sealed and connected to the periphery of the substrate.

[0028] More preferably, in step S8, the protective cover and the substrate are connected by bolts to facilitate disassembly and maintenance. The connection perimeter can be sealed with a gasket that meets the hygiene requirements for ice making or sealed with sealant material.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] 1. Compared to traditional circular or elliptical cross-section copper tubes that make linear contact with the substrate through brazing, this invention replaces the traditional copper tubes with a heat transfer medium channel. The channel plate with a zigzag groove layout is combined with the substrate to form a zigzag heat transfer medium channel. The heat transfer medium is in direct contact with the substrate and exchanges heat with the water / ice in the ice mold. The heat transfer area of ​​the substrate covers the entire heat transfer area of ​​the substrate, and the heat transfer area density is increased by orders of magnitude. At the same time, the number of heat transfer process steps is reduced, the contact thermal resistance between the heat transfer medium channel and the substrate is eliminated, and the overall thermal resistance of the heat transfer process is reduced, thereby significantly improving the heat transfer efficiency.

[0031] 2. By completely covering and wrapping the back side of the flow channel plate with heat insulation material, heat loss to the back side environment during the flow of the heat medium is effectively blocked, resulting in a good one-sided heat transfer effect. The cold energy can only be transferred from the front side of the substrate towards the ice mold, eliminating heat leakage loss on the back side of the flow channel plate and eliminating heat cancellation during the block ice formation process. As a result, the system's refrigeration efficiency and block ice production efficiency are significantly improved.

[0032] 3. The hot medium flow channel of the fixed connection between the substrate and the flow channel plate of the present invention is formed by pressure welding at the boundary line and dividing line of the zigzag flow channel. The substrate and the flow channel plate are sealed and welded around the periphery to form a weld line. The connection between the ice mold fins and the substrate is also formed by pressure welding. The pressure welding process results in small component deformation, uniform weld line, good sealing effect, and the ability to withstand vibration and thermal stress impact. The heat transfer performance is stable and the heat flux density in each area is uniform, so that the ice generation speed of each ice block in the ice mold is uniform and the shape and size of the ice blocks are consistent.

[0033] 4. This invention uses a protective cover as the exposed surface of the back side of the heat exchanger. The surface of the protective cover is smooth and flat, eliminating the gaps between the copper tubes and the substrate, as well as the uneven structural dead corners found in traditional copper tube heat exchangers. During routine maintenance, operators can directly wipe the outer surface of the protective cover, making cleaning simple and quick, and preventing dirt from accumulating. Simultaneously, the protective cover is seamlessly connected to the substrate, completely enclosing the insulation material and flow channel plate within it, further preventing external contaminants from entering the heat exchanger. This helps maintain a clean and hygienic environment for ice formation over the long term, ensuring the hygienic and safe quality of the ice from the source of the equipment.

[0034] 5. The manufacturing method of this invention integrally forms a continuous zigzag groove on the flow channel plate through a stamping process. Compared with the multiple processes of bending, positioning, and welding of traditional copper tubes, this significantly simplifies the forming process of the heat medium channel, reduces the number of parts, and improves production efficiency. The flow channel plate and the substrate are connected by a pressure welding process, achieving a metallurgical bond between them in the solid state. Compared to fusion welding, pressure welding has the following significant advantages: No filler metal is required during the welding process, avoiding potential pollution of the ice-making environment by residual solder; the bonding interface formed by pressure welding is dense and uniform, free from welding defects such as porosity and slag inclusions, resulting in high connection strength and good sealing; pressure welding has low heat input and a narrow heat-affected zone, effectively preventing warping deformation of thin plates due to high temperatures, ensuring the flatness and dimensional accuracy of the mating surface between the substrate and the flow channel plate, thereby ensuring the consistency of the cross-sectional shape of the zigzag flow channel; the flow channel plate and the substrate are sealed together by welding, and the peripheral welding can be reinforced using laser-penetrating interval welding, which not only ensures the connection strength between the flow channel plate and the substrate but also facilitates the sealing of the heat medium flow channel, thus helping to ensure the dimensional accuracy and flatness of the product. Furthermore, the filling method of the insulation material is adapted to the connection method between the protective cover and the substrate, as well as the need for convenient disassembly and maintenance. Polyurethane foam raw material can be used, which is quantitatively injected into the closed cavity after the protective cover is fastened, and then foamed and cured. This filling method is simple to operate and provides uniform filling. During the foaming process, the polyurethane foam can automatically fill various irregular gaps on the back side of the flow channel plate, eliminating the need for additional processing of the shape and size of the insulation layer, further reducing manufacturing difficulty and cost. Alternatively, a solid rectangular flat plate of insulation material of a predetermined size can be used to fill the protective cover before it is fastened to the periphery of the substrate, and then the protective cover is fastened and fixed to the periphery of the substrate. Overall, the structural design and manufacturing method of this invention are compatible, suitable for mass production, and exhibit good product consistency and quality stability, which is conducive to widespread application. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the fin arrangement on the front side in the embodiment;

[0036] Figure 2 for Figure 1 Schematic diagram of the heat exchanger cross-section along the AA direction;

[0037] Figure 3 This is a schematic diagram of the flow channel plate groove arrangement and the connection between the heat medium inlet and outlet pipes in the embodiment;

[0038] Figure 4 This is a schematic diagram of the heat transfer process of the ice mold heat exchanger of the present invention during the ice-making process;

[0039] Figure 5 This is a schematic diagram of the heat transfer process in a traditional ice mold heat exchanger during ice making.

[0040] In the picture:

[0041] 1. Substrate; 2. Flow channel plate; 3. Heat medium flow channel; 4. Heat medium inlet pipe; 5. Heat medium outlet pipe; 6. Protective cover; 7. Insulation material; 8. Horizontal fins; 9. Vertical fins; 10. Ice mold; 11. Sealing line. Detailed Implementation

[0042] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0043] It should be noted in advance that, in this invention, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances. Furthermore, in this invention, unless otherwise explicitly specified and limited, "on" or "under" a second feature can include direct contact between the first and second features, or contact between the first and second features not in direct contact but through another feature between them.

[0044] like Figures 1 to 3 As shown, the present invention provides an ice mold heat exchanger structure, which is mainly used in ice-making equipment as the core heat exchange component for ice making. In terms of overall structure, the ice mold heat exchanger mainly includes a base plate 1, an ice mold 10 disposed on the front side (also known as the front or ice-making side) of the base plate 1, a heat medium flow channel 3 disposed on the back side (also known as the back or heat exchange side) of the base plate 1, and heat insulation material 7 and protective cover 6 disposed sequentially on the back of the flow channel plate 2 of the heat medium flow channel 3.

[0045] The substrate 1 serves as the basic load-bearing component and heat transfer channel of the entire heat exchanger, connecting other components of the heat exchanger such as the transverse fins 8 and longitudinal fins 9 of the ice mold 10, the flow channel plate 2, and the protective cover 6. The substrate 1 is preferably made of a metal material with good thermal conductivity, such as aluminum, copper, or stainless steel, and its thickness can be selected according to the actual heat exchanger manufacturing process requirements. In this embodiment, the substrate 1 is made of stainless steel sheet with a thickness of 1.5–4.0 mm. Stainless steel sheet not only has good thermal conductivity but also good mechanical properties, making it easy to ensure hygienic conditions during ice production.

[0046] like Figure 1 and Figure 2As shown, the ice mold is disposed on the front side of the substrate 1. The ice mold includes multiple transverse fins 8 and longitudinal fins 9 arranged horizontally and vertically on the front side of the substrate 1. The transverse fins 8 and longitudinal fins 9 can be fixedly connected to the substrate 1 by welding, riveting, or integral casting. In this embodiment, the transverse fins 8 and longitudinal fins 9 are preferably fixed to the front side of the substrate 1 by welding. The transverse fins 8 and longitudinal fins 9 are also preferably made of a metal material with good thermal conductivity, such as stainless steel sheet, with a thickness of typically 1.0 to 3.0 mm. The height (i.e., the length of the transverse fins 8 and longitudinal fins 9 extending forward from the surface of the substrate 1) can be designed according to the required ice size, typically 10 mm to 40 mm.

[0047] After multiple transverse fins 8 and longitudinal fins 9 are arranged in a crisscross pattern, multiple ice-making molds 10 are formed between the transverse fins 8 and longitudinal fins 9 and the substrate 1. Each ice-making mold 10 has a grid-like cavity structure with an opening on one side, meaning the opening of the ice-making mold 10 faces the front of the substrate 1 (away from the substrate 1). During ice making, water is injected into each ice-making mold 10. Within the ice-making mold 10, the water exchanges heat with the heat medium in the heat medium flow channel through the substrate 1 and the transverse and longitudinal fins 8 and 9, releasing heat and then condensing into ice cubes. The shape and size of the ice-making molds 10 determine the shape and size of the final ice product.

[0048] Furthermore, such as Figure 1 As shown, the longitudinal fins 9 are arranged along the longitudinal direction and are perpendicular to the front side of the substrate 1, meaning the angle between the longitudinal fins 9 and the substrate 1 is approximately 90°. The transverse fins 8 are arranged along the transverse direction, but are not perpendicular to the substrate 1; instead, they are all tilted to the same side at a certain angle before connecting to the front side of the substrate 1. In other words, all transverse fins are tilted relative to the substrate 1 with the same tilt direction and the same tilt angle. Consequently, the opening of the ice mold 10, formed by the transverse fins 8 and the longitudinal fins 9 together with the substrate 1, is also tilted to the same side (downward), meaning the opening of the ice mold 10 is not facing directly forward, but slightly downward and forward. This results in the ice blocks produced by the ice mold 10 having an oblique prismatic structure.

[0049] As a preferred embodiment, the tilt angle of the transverse fins 8 is 5° to 15°. This tilt angle refers to the offset of the angle between the transverse fins 8 and the front side of the substrate 1 from 90°, which can also be understood as the deflection angle of the transverse fins 8 relative to the normal direction of the substrate 1. In this embodiment, the tilt angle of the transverse fins 8 is preferably 10°. The direct technical effect of uniformly tilting the transverse fins 8 is that when the ice block is separated from the inner wall of the ice mold 10 by a traditional demolding method (such as ice-making heat medium reverse circulation demolding, electric heating demolding, or mechanical knocking demolding), since the opening of the ice mold 10 is tilted downwards, the ice block will automatically slide out of the ice mold 10 along the tilt direction under its own gravity, without the need for additional flipping or pushing mechanisms. As a result, the ice falling speed is accelerated, the ice falling cycle is shortened, and the ice block is prevented from staying in the ice mold 10 and affecting the next round of ice making, thus improving the overall working efficiency of the ice making equipment.

[0050] The following description focuses on the heat medium flow channel structure located on the back side of substrate 1.

[0051] like Figure 2 As shown, the zigzag-shaped heat medium channel 3 is actually a continuous heat medium channel with a cross-section that is approximately flat and tubular, formed by the zigzag-shaped groove on the channel plate 2 and the back side of the substrate 1.

[0052] The heat transfer medium channel 3 includes a substrate 1 and a channel plate 2 fixedly connected to the back side of the substrate 1. The heat transfer medium channel replaces the copper pipes (heat transfer medium pipes) in the traditional ice mold heat exchanger structure. The channel plate 2 is preferably made of a metal material with good thermal conductivity, such as aluminum plate, copper plate, or stainless steel plate, and its thickness is usually 1.0 mm to 3.0 mm. In this embodiment, the channel plate 2 is made of stainless steel sheet material with a thickness of 1.5 mm.

[0053] The inner surface of the flow channel plate 2, that is, the side of the flow channel plate 2 facing the substrate 1, or the front surface of the flow channel plate 2, is provided with a continuous zigzag groove. This zigzag groove is a recessed groove formed on the inner surface of the flow channel plate 2 by a stamping process. The stamping process has high production efficiency, good dimensional accuracy, and is suitable for mass production, ensuring that the cross-sectional shape of the zigzag groove is consistent and the surface is smooth.

[0054] The flow channel plate 2 and the substrate 1 are fixedly connected by welding at the groove dividing lines and edge lines, forming a zigzag-shaped heat medium flow channel, i.e., a zigzag-shaped flow channel. Since the flow channel plate 2 and the substrate 1 are directly bonded and welded at the dividing lines and edge lines between the zigzag-shaped grooves, a specific welding method, such as pressure welding, is required for the welding at these points. Pressure welding, under pressure, causes the substrate 1 and the flow channel plate 2 to achieve atomic bonding in the solid state at the dividing lines and edge lines of the zigzag-shaped grooves of the flow channel plate 2, forming a zigzag-shaped heat medium flow channel 3. Furthermore, the periphery of the flow channel plate 2 and the substrate 1 are also sealed by welding, forming a sealing line 11.

[0055] Pressure welding, also known as solid-state welding, includes explosive welding, cold pressure welding, friction welding, diffusion welding, ultrasonic welding, high-frequency welding, and resistance welding. It can be used to weld small, precision, and complex parts for which fusion welding and brazing are insufficient to meet quality requirements, such as manufacturing closed-shaped parts. Many materials that are difficult to weld using fusion welding can often be pressure welded into high-quality joints with the same strength as the base material.

[0056] Pressure welding applies pressure without filler material during the welding process, and there is no melting process. Therefore, unlike fusion welding, there is no loss of beneficial alloying elements or intrusion of harmful elements into the weld. This ensures the sealing of the heat medium flow channel 3, simplifies the welding process, and improves welding safety and hygiene. At the same time, because the heating temperature is lower and the heating time is shorter than that of fusion welding, the heat-affected zone is smaller, the heat exchanger structure deformation is smaller, and the welding is more uniform. As a result, during the block ice production process, the heat flux density is uniform in all areas of the heat exchanger, and the block ice in each ice compartment is uniformly formed.

[0057] The width and depth of the zigzag groove can be designed according to the heat medium flow rate and heat exchange requirements. The zigzag groove extends continuously on the inner side of the flow channel plate 2 in a zigzag (or serpentine, S-shaped) trajectory. Its overall layout roughly covers the entire outer heat exchange area of ​​the substrate 1, and the corresponding heat transfer area also roughly covers the entire outer heat exchange area of ​​the substrate 1.

[0058] The cross-sectional shape of the zigzag groove can be semi-circular, arc-shaped, U-shaped, rectangular, or trapezoidal, etc. In this embodiment, the cross-sectional shape of the zigzag groove is preferably arc-shaped. The arc-shaped cross-section of the heat medium flow channel helps to increase the heat exchange area and reduce the flow resistance of the heat medium. At the same time, the arc-shaped cross-section is also convenient for stamping and forming.

[0059] The heat transfer medium channel 3 is a channel through which liquid or gaseous heat transfer medium (such as refrigerant or coolant) flows. When the heat transfer medium flows along the zigzag direction within the heat transfer medium channel 3, heat is mainly transferred through the substrate 1. Compared to the traditional ice film heat exchanger structure with zigzag copper tubes brazed to the outside of the substrate, where the heat transfer medium first exchanges heat with the copper tubes via convection, and the copper tubes further conduct heat to the substrate, the heat transfer medium of this invention directly exchanges heat with the substrate 1 via convection. The convection heat exchange surface basically covers the entire heat transfer area of ​​the substrate 1, achieving an order-of-magnitude increase in heat transfer area. At the same time, it reduces heat transfer links, eliminates the contact thermal resistance between the heat transfer medium channel 3 and the substrate 1, reduces the overall thermal resistance, and significantly improves heat transfer efficiency and uniformity.

[0060] The heat medium flow channel 3 has a heat medium inlet and a heat medium outlet at each end. Specifically, the heat medium flow channel 3 has a starting end and a ending end, with the starting end serving as the heat medium inlet and the ending end serving as the heat medium outlet.

[0061] The heat exchanger also includes a heat medium inlet pipe 4 and a heat medium outlet pipe 5. One end of the heat medium inlet pipe 4 is connected to the starting end of the aforementioned heat medium flow channel 3, and the other end extends outward to connect to an external heat medium supply pipeline. One end of the heat medium outlet pipe 5 is connected to the ending end of the aforementioned heat medium flow channel 3, and the other end extends outward to connect to an external heat medium return pipeline.

[0062] Furthermore, the heat exchanger also includes a protective cover 6 disposed on the back side of the flow channel plate 2. The protective cover 6 covers the flow channel plate 2 and the insulation material 7, which will be mentioned later. The protective cover 6 is preferably made of sheet metal by stamping, such as aluminum or stainless steel, or a plastic part that meets hygiene, safety, and mechanical performance requirements. Its shape is generally a box-shaped or cover-like structure with one flat side, four vertical folded edges, and one open side. The open side of the protective cover 6 faces the back side of the substrate 1, and the cover part faces the back side of the flow channel plate 2, that is, away from the substrate 1, thereby forming a receiving cavity between the protective cover 6 and the flow channel plate 2, which is filled with the insulation material 7.

[0063] The side flange of the protective cover 6 is closedly connected to the periphery of the substrate 1. The closed connection between the protective cover 6 and the substrate 1 can be achieved in various ways, such as welding, riveting, snap-fitting, or bolting, depending on the structural and process requirements. For example, in one embodiment, the stainless steel protective cover 6 has a flange on its edge, which fits against the peripheral surface of the substrate 1 and is fixedly connected to the periphery of the substrate 1 by welding, ensuring connection strength. In another embodiment, the edge of the protective cover 6 is fixedly connected to the periphery of the substrate 1 by riveting, and a sealing gasket (e.g., a rubber gasket or silicone gasket) or sealant is sandwiched between them to achieve a seal. In yet another embodiment, the edge of the protective cover 6 is detachably connected to the periphery of the substrate 1 by bolt fasteners, and sealant is applied to the connection surface or a sealing gasket is provided to achieve a seal. Regardless of the specific connection method used, the purpose is to form a closed space between the protective cover 6 and the substrate 1, and this closed space has good airtightness.

[0064] In this embodiment, in order to facilitate subsequent disassembly and cleaning, the side folds of the protective cover 6 are preferably connected to the periphery of the substrate 1 by bolts. The bolt connection method is reliable and easy to disassemble.

[0065] A filling cavity is formed between the flow channel plate 2 and the protective cover 6 (i.e., between the back side of the flow channel plate 2 and the inner wall of the protective cover 6). This filling cavity is filled with thermal insulation material 7. The thermal insulation material 7 can be a material that meets the hygiene and safety requirements for ice making and has a low thermal conductivity. In this embodiment, the thermal insulation material 7 is preferably rigid polyurethane foam. Polyurethane foam has advantages such as low thermal conductivity, low density, high closed-cell rate, and good waterproof and moisture-proof performance, and it has good adhesion to metal walls, making it suitable for filling closed cavities in heat exchangers. Alternatively, a flat rectangular solid thermal insulation material of a predetermined size can also be used.

[0066] The filling method of the heat insulation material 7 is as follows: Before the protective cover 6 is sealed and connected to the substrate 1, the flow channel plate 2 is first fixedly connected to the back side of the substrate 1, and then polyurethane foam raw material is filled into the back side and surrounding area of ​​the flow channel plate 2. Then, the protective cover 6 is fastened to the back side of the substrate 1 and sealed. The polyurethane foam raw material undergoes a foaming reaction in the closed cavity inside the protective cover 6, and after expanding and curing, it completely fills the gap between the flow channel plate 2 and the protective cover 6. Another filling method is to place a flat rectangular solid heat insulation material of a predetermined size on the protective cover 6 before fastening the protective cover 6 to the substrate 1, and then fold the edges of the protective cover 6 to seal and connect it to the periphery of the substrate 1.

[0067] The main function of the heat insulation material 7 is to prevent heat loss to the back side of the flow channel plate 2 (i.e., the direction of the protective cover 6) when the heat medium flows in the heat medium channel 3. Since the heat insulation material 7 completely wraps and insulates the back side of the flow channel plate 2, the heat (or coldness) of the heat medium in the heat medium channel 3 cannot be transferred through the back side of the flow channel plate 2. The direction of heat transfer is essentially limited to transfer only through the substrate 1 towards the ice mold on the front side. This results in a good one-sided heat transfer effect, meaning that heat (or coldness) can only be transferred from the substrate 1 and its front side to the transverse fins 8 and longitudinal fins 9 and the water / ice in the ice mold 10, while heat leakage on the back side is essentially eliminated. The heat insulation material 7 ensures that the coldness or heat carried by the heat medium is used to the maximum extent for cooling the water in the ice mold 10 and forming block ice, eliminating heat loss during the block ice formation process, and significantly improving system energy efficiency and production efficiency.

[0068] The outer surface (i.e., the back side) of the protective cover 6 is smooth and flat, eliminating problems such as exposed copper tubes, uneven surfaces, and narrow gaps between the copper tubes and the substrate, common in traditional ice mold heat exchanger structures where copper tubes are the heat medium. During long-term use, the smooth outer surface of the protective cover 6 is easy and quick to clean, eliminating hard-to-reach areas for dirt and grime, thus helping to maintain the overall hygiene of the heat exchanger and ensuring the hygienic quality of ice production. Simultaneously, the protective cover 6 also protects the internal flow channel plate 2 and insulation material 7, preventing external dust, oil, and other impurities from entering the heat exchanger.

[0069] This embodiment also provides a method for manufacturing the above-mentioned ice mold heat exchanger, which includes the following steps:

[0070] S1. Make ice molds by welding multiple longitudinal fins 9 and multiple transverse fins 8 to the front side of the substrate 1 in a crisscross pattern. The longitudinal fins 9 are perpendicular to the substrate 1, and the transverse fins 8 are uniformly welded to the substrate 1 at a certain angle to the same side, forming multiple ice molds 10 with one side open and arranged in a matrix.

[0071] S2. Make flow channel plate 2. Take a metal plate and punch out continuous zigzag grooves on its inner side by stamping.

[0072] S3. Through holes are opened at both ends of the zigzag groove, and heat medium inlet pipe 4 and heat medium outlet pipe 5 are welded to the through holes, so that heat medium inlet pipe 4 and heat medium outlet pipe 5 are connected to the interior of the zigzag groove.

[0073] S4. The flow channel plate 2 is attached to the back side of the substrate 1 with its inner side facing the back side of the substrate 1, so that the outer contour of the flow channel plate 2 matches the outer contour of the substrate 1. Then, the flow channel plate 2 and the peripheral contact edge of the substrate 1 are sealed and connected by welding.

[0074] S5. Along the edge line and the dividing line of the zigzag groove, the flow channel plate 2 and the substrate 1 are pressure welded and fixed to form a welding line, so that a closed zigzag flow channel 3 is formed between the zigzag groove and the back side of the substrate 1.

[0075] S6. Two through holes or notches are made on the side fold of the protective cover 6 for the heating medium inlet pipe 4 and the heating medium outlet pipe 5 to pass through. The heating medium inlet pipe 4 and the heating medium outlet pipe 5 are passed through the corresponding through holes or notches respectively. Then the protective cover 6 is fastened to the back side of the flow channel plate 2 and closed and connected to the periphery of the base plate 1.

[0076] S7. There are two paths or schemes for setting the heat insulation material 7: one is to inject polyurethane foam raw material into the cavity between the back side of the flow channel plate 2 and the protective cover 6, and the polyurethane foam raw material foams and solidifies in the closed cavity inside the protective cover 6 to form the heat insulation material 7 filling the space between the flow channel plate 2 and the protective cover 6; the other is to place a rectangular flat solid heat insulation material of a predetermined size inside the protective cover 6 before fastening the protective cover 6 to the back side of the flow channel plate 2 and sealing it with the periphery of the substrate 1.

[0077] S8. The peripheral sealing connection between the protective cover 6 and the substrate 1 can be achieved by welding, riveting, or bolting. The connection perimeter can be sealed with a gasket that meets the hygiene requirements for ice making or with sealant material.

[0078] Before describing the ice-making process of the ice mold heat exchanger in this embodiment, the advantages of the ice mold heat exchanger in the heat transfer process compared with the existing ice mold heat exchangers will be demonstrated through the principle. Figure 4 The heat medium flow channel 3 of the ice mold heat exchanger of the present invention is composed of a flow channel plate 2 and a base plate 1. The heat medium is in direct contact with the base plate 1. A heat insulation material 7 is provided on the back side of the heat medium flow channel 3 inside the protective cover 6, which restricts the heat transfer direction of the heat medium in the heat medium flow channel 3. This ensures that the heat medium in the heat medium flow channel 3 will almost only transfer heat towards the front fins and water / ice, basically avoiding heat loss to the air in the block ice formation environment through the back side of the heat medium flow channel 3, eliminating heat leakage loss of the heat exchanger, and eliminating heat cancellation in the block ice formation process. Figure 5In the existing ice mold heat exchanger shown, during the ice-making process, a portion of the heat from the heat medium inside the copper tube is transferred through the contact line between the copper tube and the substrate, conducting heat to the substrate and further to the fins, and then to the water / ice inside the ice mold. Simultaneously, another portion of heat is lost from the back side of the copper tube to the air in the ice-forming environment, resulting in heat leakage. The air exchanges heat with the water / ice inside the ice mold, creating a heat cancellation effect during ice formation. Because the circular cross-section copper tube and substrate are connected in a zigzag shape by brazing in the traditional ice mold heat exchanger structure, the heat transfer area between the copper tube and the substrate is very limited. During production, thermal stress and operational vibrations can damage the connection between the copper tube and the substrate, causing a rapid increase in the contact thermal resistance. Therefore, the traditional ice mold heat exchanger structure has low heat transfer efficiency and rapid performance degradation.

[0079] Obviously, compared with the traditional ice mold heat exchanger structure, the ice mold heat exchanger structure of this invention replaces the traditional copper pipe with a heat medium flow channel 3, and is equipped with a protective cover 6 and insulation material 7, which has significant advantages in thermal performance, manufacturing materials, and process flow. The flow channel plate 2 and the substrate 1 of this invention form the heat medium flow channel 3 through a pressure welding process. The heat flow path of the substrate 1 covers the entire heat exchange area of ​​the substrate 1, resulting in an order-of-magnitude increase in heat exchange area. This reduces the number of heat transfer process steps, eliminates the thermal resistance of heat conduction contact between the heat medium channel 3 and the substrate 1, and lowers the total thermal resistance of the heat transfer process. Because the insulation material covers the entire back side of the flow channel plate 2, heat leakage loss from the heat medium channel 3 is eliminated, thereby eliminating heat offset during the block ice formation process and improving the block ice production speed and system energy efficiency.

[0080] The working process of the ice mold heat exchanger of the present invention in an ice-making device is described in detail below.

[0081] Ice-making stage: The ice mold heat exchanger of the present invention is installed in the ice-making equipment. The inlet pipe 4 is connected to the refrigerant circulation supply pipe of the ice-making system, and the outlet pipe 5 is connected to the refrigerant circulation return pipe of the refrigeration system. The refrigerant (as a heat medium) enters the heat medium flow channel 3 through the inlet pipe 4 and flows in a zigzag direction within the heat medium flow channel 3. The refrigerant evaporates and absorbs heat within the heat medium flow channel 3, causing the temperature of the substrate 1, the transverse fins 8, and the longitudinal fins 9 to drop below the freezing point. At the same time, water is injected into or continuously sprayed into each ice mold 10 on the front side of the substrate 1. Specifically, the common water-flow ice-making principle can be adopted. The heat medium in the heat medium flow channel 3 exchanges heat with the water / ice in the ice mold 10 through the substrate 1, the transverse fins 8, and the longitudinal fins 9. After releasing heat, the water temperature decreases and gradually condenses into ice within the ice mold 10. During this process, since the back side of the flow channel plate 2 is filled with heat insulation material 7, the heat (actually cold transfer) of the refrigerant in the heat medium flow channel 3 can only be transferred from the front side of the substrate 1 to the substrate 1, the ice mold 10, and the water / ice. The heat transfer from the back side to the air is blocked, eliminating heat leakage loss during the heat transfer process and eliminating heat offset during the block ice formation process. The refrigeration efficiency of the ice making system is greatly improved.

[0082] De-icing stage: After the water in the ice mold 10 has completely frozen into ice, the ice needs to be removed from the ice mold 10. First, a traditional demolding method is used (such as refrigerant reverse circulation de-icing, where high-temperature, high-pressure refrigerant is introduced into the heat medium channel 3, raising the temperature of the substrate 1, transverse fins 8, and longitudinal fins 9, causing slight melting of the ice surface on the inner wall of the ice mold 10, breaking the adhesion between the ice and the inner wall of the ice mold 10, and achieving initial separation of the ice from the mold wall). After the ice separates from the inner wall of the ice mold 10, since all transverse fins 8 are uniformly tilted to the same side, and the opening of the ice mold 10 faces slightly downwards, the ice automatically slides out of the opening of the ice mold 10 under its own gravity along the tilt direction of the ice mold 10 and falls into the ice collection tank or conveying device below. The entire ice-falling process does not require additional mechanical flipping or pushing devices; the ice-falling speed is fast and there is no jamming, which helps to shorten the ice-making cycle and increase the ice production per unit time. Similar to the ice-making stage, the heat transfer in the heat medium flow channel 3 during the de-icing stage is unidirectional, transferring heat to the substrate 1, the ice mold 10, and the water / ice.

[0083] It should be noted that the demolding method used in this invention (i.e., the method of separating the ice block from the inner wall of the ice mold 10) can be any conventional demolding method in the prior art, such as refrigerant reverse circulation demolding, electric heating demolding, hot water spraying demolding, mechanical knocking demolding, etc. The focus of this invention is not on how to separate the ice block from the wall, so it will not be described in detail here.

[0084] To facilitate understanding by those skilled in the art of the improvements of this invention over the prior art, some of the accompanying drawings and descriptions have been simplified. The above embodiments are preferred implementations of this invention. In addition, this invention can be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this invention.

Claims

1. An ice mold heat exchanger, characterized in that: The device includes a substrate (1), an ice mold (10), a heat medium channel (3), a protective cover (6), a heat insulation material (7), a heat medium inlet pipe (4), and a heat medium outlet pipe (5). The ice mold (10) and the heat medium channel (3) are respectively disposed on both sides of the substrate (1). The protective cover (6) is disposed on the back side of the heat medium channel (3). The heat insulation material (7) is disposed in the cavity between the heat medium channel (3) and the protective cover (6). The two ends of the heat medium channel (3) are respectively connected to the heat medium inlet pipe (4) and the heat medium outlet pipe (5). The water or ice in the ice mold (10) and the heat medium in the heat medium channel (3) exchange heat. The heat insulation material (7) is used to restrict the heat medium in the heat medium channel (3) from unidirectionally transferring heat towards the ice mold (10).

2. The ice mold heat exchanger according to claim 1, characterized in that: The ice mold includes a plurality of transverse fins (8) and longitudinal fins (9) arranged on the front side of the substrate (1), the transverse fins (8) and longitudinal fins (9) forming a plurality of ice molds (10) with the substrate (1) having one side open and arranged in a matrix.

3. The ice mold heat exchanger according to claim 2, characterized in that: The longitudinal fins (9) are arranged in the longitudinal direction and vertically connected to the substrate (1), and the transverse fins (8) are arranged in the transverse direction and uniformly tilted to the same side at a certain angle and connected to the substrate (1), so that the opening of the ice mold (10) is tilted downward.

4. The ice mold heat exchanger according to claim 3, characterized in that: The tilt angle of the transverse fin (8) is 5° to 15°.

5. The ice mold heat exchanger according to claim 1, characterized in that: The heat medium flow channel (3) includes a substrate (1) and a flow channel plate (2) fixedly connected to the back side of the substrate (1). The inner side of the flow channel plate (2) is provided with a continuous zigzag groove. The zigzag groove and the back side of the substrate (1) form a zigzag heat medium flow channel (3). The water or ice in the ice mold (10) exchanges heat with the heat medium in the heat medium flow channel (3).

6. The ice mold heat exchanger according to claim 5, characterized in that: The zigzag groove on the inner side of the flow channel plate (2) is formed by stamping. The flow channel plate (2) and the substrate (1) are connected by welding at the edge line and the dividing line of the zigzag groove to form the zigzag heat medium flow channel (3). The flow channel plate (2) and the substrate (1) are connected by welding to form a sealing line (11). The heat medium in the heat medium flow channel (3) covers the entire back heat transfer area of ​​the substrate (1) through the heat transfer area of ​​the substrate (1).

7. The ice mold heat exchanger according to claim 1, characterized in that: The protective cover (6) is an open box-shaped structure with a rectangular flat plate with folded edges on all four sides. Its folded edges are closed and connected to the periphery of the substrate (1). The heat insulation material (7) is filled in the cavity formed between the flow channel plate (2) and the protective cover (6).

8. The ice mold heat exchanger according to claim 1, characterized in that: The heat medium inlet pipe (4) is connected to the inlet of the heat medium flow channel (3) and extends to the outside through the side fold of the protective cover (6); the heat medium outlet pipe (5) is connected to the outlet of the heat medium flow channel (3) and extends to the outside through the side fold of the protective cover (6).

9. A method for manufacturing an ice mold heat exchanger as described in any one of claims 2 to 7, characterized in that, Includes the following steps: S1. Make ice molds by welding multiple longitudinal fins (9) and multiple transverse fins (8) to the front side of the substrate (1) in a crisscross pattern. The longitudinal fins (9) are perpendicular to the substrate (1), and the transverse fins (8) are uniformly welded to the substrate (1) at a certain angle to the same side, forming multiple ice molds (10) with one side open and arranged in a matrix. S2. Make the flow channel plate (2). Take a metal plate and punch out a continuous zigzag groove on its inner side by stamping. S3. Through holes are opened at both ends of the zigzag groove, and heat medium inlet pipe (4) and heat medium outlet pipe (5) are welded to the through holes, so that the heat medium inlet pipe (4) and heat medium outlet pipe (5) are connected to the interior of the zigzag groove. S4. The flow channel plate (2) is attached to the back side of the substrate (1) with its inner side facing the back side of the substrate (1) so that the outer contour of the flow channel plate (2) matches the outer contour of the substrate (1). Then, the flow channel plate (2) and the peripheral contact edge of the substrate (1) are sealed and connected by welding. S5. Along the edge line and the dividing line of the zigzag groove of the flow channel plate (2), the flow channel plate (2) and the substrate (1) are pressure welded and fixed to form a welding line, so that a closed zigzag flow channel (3) is formed between the zigzag groove and the back side of the substrate (1). S6. Two through holes or notches are made on the side edge of the protective cover (6) for the heat medium inlet pipe (4) and the heat medium outlet pipe (5) to pass through. The heat medium inlet pipe (4) and the heat medium outlet pipe (5) are passed through the corresponding through holes or notches respectively. Then the protective cover (6) is fastened to the back side of the flow channel plate (2) and closed and connected to the periphery of the base plate (1). S7. Filling with heat insulation material: Inject polyurethane foam raw material into the cavity between the back side of the flow channel plate (2) and the protective cover (6). The polyurethane foam raw material foams and solidifies in the closed cavity inside the protective cover (6) to form heat insulation material (7) filling the space between the flow channel plate (2) and the protective cover (6); or, before fastening the protective cover (6) to the back side of the flow channel plate (2), place a rectangular flat solid heat insulation material of a predetermined size inside the protective cover (6), and then fasten the protective cover (6) to the back side of the flow channel plate (2) and seal it to the periphery of the substrate (1). S8. The protective cover (6) and the substrate (1) are connected by one or more of welding, riveting, and bolting. The connection is also sealed by a gasket that meets the hygiene requirements for ice making or by using sealant material.

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