Heating device and manufacturing method therefor

Abstract

A heating device and a manufacturing method therefor, relating to the technical field of electric heating. The heating device comprises: a first cover plate (1), the first cover plate being provided with a continuous protrusion (7) including bent segments and straight segments; a second cover plate (2), the second cover plate being attached to the side of the first cover plate (1) opposite to the protrusion (7), and covering an inner cavity of the protrusion (7) to form a chamber (9), wherein the first cover plate (1) and the second cover plate (2) define, at the chamber (9), a flow region for fluid flow, and two ends of the protrusion (7) are provided with through-holes (8) in communication with the chamber (9); a peripheral weld seam, welded onto the first cover plate (1) and the second cover plate (2) and enclosing the exterior of the flow region; and a gap weld seam, welded in a gap at the root of adjacent straight segments of the protrusion (7), wherein the end of the gap weld seam at the opening of the gap is connected to the peripheral weld seam. The peripheral weld seam and the gap weld seam serve to seal the periphery of the chamber (9), and the entire welding process is performed in the plane of the first cover plate (1), effectively avoiding uphill welding required for sealing by welding, thereby improving the sealing performance of welding while reducing welding difficulty.

Description

A heating device and its manufacturing method Technical Field

[0001] This invention relates to the field of electrical heating technology, specifically to a heating device and its manufacturing method. Background Technology

[0002] For household appliances, heating devices are typically electric heating elements or heating plates. An electric heating element is a device that uses electrical energy to generate heat; when an electric current passes through it, heat is generated, thus heating water or other liquids. A heating plate, on the other hand, is a device that uses electromagnetic induction to generate heat; when an electric current passes through it, a magnetic field is generated, thus heating water or other liquids. These heating devices are commonly used in appliances such as hot water dispensers, coffee makers, tea makers, and garment steamers to heat water or generate steam for use.

[0003] Based on the applicant's thorough search, as proposed in Chinese Patent Publication No. CN217266537U, "A Steam Generator and Garment Steamer," a second cover plate is closed to define a closed space with an inlet and an outlet. A baffle divides the closed space into a water channel extending from the inlet to the outlet. The heating component and the evaporation component transfer heat through contact to heat the water channel of the closed space. The second cover plate and the other cover plate are in sealed contact, welded, or bonded. If welding is used for the second cover plate and the second cover plate, the following shortcomings of this solution apply:

[0004] Because the baffles on the second cover plate separate the enclosed space, in order to ensure the continuity of the waterway, it is necessary to weld the baffles and their outer perimeter to form a completely closed waterway with only one flow direction. However, when welding the baffles and the outer frame of all the baffles, there is a slope at the welded connection between the baffles and their outer perimeter, and the weld point is sloping. This makes it difficult to weld on the slope, increases the difficulty of welding, and also easily affects the quality of the slope welding. This can easily lead to leakage in the waterway at the slope, affecting the waterway's sealing performance. Summary of the Invention

[0005] This invention provides a heating device and its manufacturing method, which solves the problem that the slope at the welded connection between the retaining rib and the periphery of the retaining rib affects the quality of the climbing weld.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A heating device includes a first cover plate having a continuous protrusion with curved and straight sections; a second cover plate fitted to the opposite side of the first cover plate relative to the protrusion and covering the inner cavity of the protrusion to form a chamber, the first and second cover plates forming a flow area for fluid flow in the chamber, and through holes communicating with the chamber at both ends of the protrusion; an circumferential weld welded to the first and second cover plates and sealing the outside of the flow area; a gap weld welded to the gap at the root of the adjacent straight section of the protrusion, and one end of the gap opening engaging with the circumferential weld; and a heat-conducting plate and a heating element sequentially fitted to the second cover plate opposite to the chamber, the heat generated by the heating element being transferred to the chamber through the heat-conducting plate and the second cover plate.

[0008] In one embodiment, the gap between the roots of adjacent straight segments of the protrusion is L1, and the value of L1 is 1-6mm.

[0009] In one embodiment, the cross-section of the chamber is trapezoidal, and the width gradually decreases in the direction away from the second cover plate.

[0010] In one embodiment, the edge of the first cover plate is bent and extended to cover the side of the second cover plate, forming a folded edge that is close to and / or fits against the side of the second cover plate.

[0011] In one embodiment, the heat-conducting plate has multiple fine grooves on the side where it is attached to the second cover plate.

[0012] In one embodiment, the heat-conducting plate has multiple blocking points on the side facing the heating element, and the blocking points rest against the side of the heating element.

[0013] In one embodiment, the folded edge height is greater than the thickness of the second cover plate.

[0014] In one embodiment, the heating element is S-shaped, U-shaped, C-shaped, or Z-shaped.

[0015] In one embodiment, both the first cover plate and the second cover plate are made of metal materials. The first cover plate, the second cover plate, and the heat-conducting plate are all made of metal materials. The first cover plate and the second cover plate are made of stainless steel, the heat-conducting plate is made of aluminum or aluminum alloy, and the heating element is a heating tube with an aluminum alloy shell.

[0016] The manufacturing method of the heating device described above includes the following steps:

[0017] Step S1: Punch the mating surface of the first cover plate to form continuous protrusions, and select a second cover plate that can fit with the mating surface of the first cover plate.

[0018] Step S2: Clean and dry the surfaces of the first and second cover plates;

[0019] Step S3: Cover and press the first cover plate and the second cover plate together, and weld several weld points in sequence along the gap at the root of the straight section of the protrusion towards its opening direction; then weld continuously along the gap and in the order of the weld points to form a gap weld; then weld the end of the gap weld located at the opening of the gap as the weld point to form a closed circumferential weld around the protrusion.

[0020] Step S4: The heat-conducting plate is attached to the side of the second cover plate away from the chamber, and the heat-conducting plate is welded and fastened to the second cover plate;

[0021] Step S5: The heating element is attached to the side of the heat-conducting plate away from the second cover plate, and the heating element is welded and fastened to the heat-conducting plate.

[0022] As can be seen from the above technical solutions, the present invention has the following beneficial effects:

[0023] This invention utilizes a protrusion on a first cover plate, a circumferential weld forming around the protrusion, and an extension weld connecting to the circumferential weld and extending to the root gap of the adjacent straight section of the protrusion. The circumferential weld and the extension weld provide a sealing effect on the periphery of the chamber. The entire welding process takes place on the plane of the first cover plate, effectively avoiding the need for sloping welding during sealing, improving the sealing performance of the weld, and reducing the difficulty of welding. This significantly improves the sealing performance of the fluid in the chamber during use. Through a simple spatial layout, structural fit, and mature manufacturing process, a low-cost heating device is achieved. This device can heat cold water and also turn cold water into steam.

[0024] By using a welding method for the heating device, the gaps of the protrusion are first spot welded, then the gaps of the protrusion are welded sequentially from the inside out, and finally the outer ends of the weld are welded sequentially to form a circumferential weld around the protrusion. This prevents the gaps of the protrusion from bulging during subsequent welding, which would affect the sealing of the weld. Attached Figure Description

[0025] Figure 1 is a schematic diagram of the exploded structure of the present invention;

[0026] Figure 2 is a schematic diagram of the side cross-sectional structure of the present invention;

[0027] Figure 3 is a schematic diagram of the front cross-sectional structure of the present invention;

[0028] Figure 4 is a schematic diagram of the structure of the present invention from a bottom view;

[0029] Figure 5 is a schematic diagram of the welding structure of the first cover plate in this invention;

[0030] Figure 6 is a schematic diagram of the structure on both sides of the heat-conducting plate of the present invention.

[0031] In the diagram: 1. First cover plate; 2. Second cover plate; 3. Heat-conducting plate; 4. Heating element; 5. Temperature limiting element; 6. Water tap; 7. Protrusion; 8. Through hole; 9. Chamber; 10. Slot; 11. Stop; 12. Fixing bracket. Embodiments of the present invention

[0032] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0033] As shown in Figures 1, 3, and 5, a heating device includes a first cover plate 1 with a continuous protrusion 7 having curved and straight sections on one side; a second cover plate 2, which is attached to the opposite side of the first cover plate 1 relative to the protrusion 7 and covers the inner cavity of the protrusion 7 to form a chamber 9. The first cover plate 1 and the second cover plate 2 form a flow area for fluid flow in the chamber 9. Through holes 8 communicating with the chamber 9 are opened at both ends of the protrusion 7; an circumferential weld is welded to the first cover plate 1 and the second cover plate 2 and seals the outside of the flow area; a gap weld is welded to the gap at the root of the adjacent straight section of the protrusion 7, and one end of the gap opening is joined to the circumferential weld; a heat-conducting plate 3 and a heating element 4 are sequentially attached to the second cover plate 2 opposite to the chamber 9, and the heat generated by the heating element 4 is transferred to the chamber 9 through the heat-conducting plate 3 and the second cover plate 2. The straight and curved sections of the protrusion 7 are designed to increase its length on the first cover plate 1. Preferably, it is serpentine, with the straight sections arranged in parallel and the curved sections located at the junctions of adjacent straight sections. Both ends of the protrusion 7 have through holes 8. After the first cover plate 1 and the second cover plate 2 are closed, fluid can flow from one end of the chamber 9 to the other. However, the fluid can easily flow directly out through the gap between the first cover plate 1 and the second cover plate 2, making it difficult for the fluid to flow through the formed chamber 9. This results in a short fluid path and affects heating. The effect is that the side of the chamber 9 is sealed by welding the circumferential weld and the extended weld around it, so that the fluid can only flow from the through hole 8 at one end to the through hole 8 at the other end along the direction of the protrusion 7. Gas or liquid can be introduced into the chamber 9, preferably water. The water flows in the chamber 9, the heating element 4 generates heat and transfers the heat to the chamber 9 through the second cover plate 2, heating the cold water in the chamber 9. At the same time, the cold water in the chamber 9 can also be heated to form steam, so that hot water or steam flows out from the through hole 8 at the other end.

[0034] The heat-conducting plate 3 transfers heat from the heating element 4 to the second cover plate 2. The second cover plate 2, the heat-conducting plate 3, and the heating element 4 are sequentially attached and fastened together by brazing. The heating element 4 generates heat and transfers it to the heat-conducting plate 3. The heat-conducting plate 3 then transfers the heat to the second cover plate 2. After being heated, the second cover plate 2 transfers the heat to the chamber 9, heating the cold water in the chamber 9 and improving the uniformity of water heating.

[0035] As shown in Figure 1, each through hole 8 is equipped with a water tap 6. The water tap 6 is preferably laser-welded to the through hole 8. The water tap 6 is used to introduce cold water into the chamber 9 or to discharge hot water / steam from the chamber 9. During the process of cold water passing through the chamber 9, it is heated by the second cover plate 2. The heated water flows along the chamber 9 and is discharged from the water tap 6 at the other end for subsequent use of hot water or steam. The first cover plate 1 has fixed brackets 12 at both ends, and both are connected by laser welding or spot welding. The fixed brackets 12 facilitate subsequent installation with household appliances.

[0036] As shown in Figures 1 and 5, the first cover plate 1 and the second cover plate 2 are attached and fixed by welding, preferably by laser welding with a laser beam of 0.5-1mm.

[0037] As shown in Figures 3 and 5, the gap between the roots of adjacent straight sections of protrusion 7 is L1, with a value of 1-6mm, preferably 2-4mm. A larger L1 value increases manufacturing costs and space occupancy; a smaller L1 value increases manufacturing difficulty and the complexity of laser welding. A specific welding example is as follows: when welding the first cover plate 1 and the second cover plate 2, for example, using a first cover plate 1 with an L1 value of 2mm and a laser beam of 0.5mm... The cover plate 1 and the second cover plate 2 are welded together. The laser beam welds the traces along the direction of the gap L1 outward. If the laser beam welding is deviated, the deviation is within 1.5mm and is within the controllable range. If the laser beam is 1mm, the deviation is still 1.5mm. During laser beam welding, it is very easy for the laser beam to deviate to the side of the protrusion 7. The side of the protrusion 7 is a single layer and is not in contact with the second cover plate 2. It is very easy for the laser beam to penetrate the single-layer slope, resulting in damage to the product seal and affecting the overall welding process.

[0038] As shown in Figure 3, the cross-section of the chamber 9 is trapezoidal, and the width gradually decreases in the direction away from the second cover plate 2. That is, the side length of the top end of the chamber 9 is smaller than the side length of the bottom end of the chamber 9. The bottom end face of the chamber 9 is in contact with the second cover plate 2, which increases the contact area between the water in the chamber 9 and the second cover plate 2, improves the heating effect of the water in the chamber 9, and achieves instant heating.

[0039] As shown in Figures 2 and 3, the edge of the first cover plate 1 is bent and extended to cover the side of the second cover plate 2, forming a folded edge that is close to or / and fits against the side of the second cover plate 2. The height of the folded edge is at least greater than the thickness of the second cover plate 2. The folded edge is used to cover the side of the second cover plate 2 and the heat-conducting plate 3, and to limit the relative movement of the first cover plate 1 and the second cover plate 2 during welding, which would affect the accuracy of welding. The height of the folded edge is greater than the thickness of the second cover plate 2, and the folded edge can extend to the side of the heat-conducting plate 3, or extend further... It covers the entire side of the heat-conducting plate 3. During welding, the top of the protrusion 7 is pressed down to facilitate the simultaneous positioning of the first cover plate 1, the second cover plate 2 and the heat-conducting plate 3, which helps with subsequent spot welding positioning and completes the welding process of the first cover plate 1 and the second cover plate 2. The second cover plate 2, the heat-conducting plate 3 and the heating element 4 are sequentially attached and fastened together by brazing. The folded edge helps to overcome the deformation problem during the forming and brazing process, so as to avoid the product arching, which would make its shape unsightly, affect assembly, and even cause the product to crack.

[0040] As shown in Figures 1 and 6, multiple fine grooves 10 are provided on the side of the heat-conducting plate 3 that is in contact with the second cover plate 2. The fine grooves 10 help to remove debris and gas during the welding of the heat-conducting plate 3.

[0041] As shown in Figures 1 and 6, the heat-conducting plate 3 has multiple abutments 11 on the side facing the heating element 4. The abutments 11 rest against the side of the heating element 4, facilitating the limiting of the heating element 4. The heat-conducting plate 3 has multiple holes through which multiple screws can pass, connected by stamping and riveting for precise positioning of the heating element 4. The height of the abutments is 2-10mm, preferably 3-6mm, used to limit the heating element 4 and prevent it from deviating from the heat-conducting plate 3 during welding.

[0042] As shown in Figures 1, 4, and 6, the heating element 4 is preferably electrically heated. It is bent and welded to the side wall of the heat-conducting plate 3. The heating element 4 is S-shaped, U-shaped, C-shaped, or Z-shaped to increase the contact area and improve the heat conduction effect. A temperature limiting element 5 is provided at the center of the bent part of the heating element 4 to save installation space. The temperature limiting element 5 is fixed to the heat-conducting plate 3, that is, it is fixed and attached to the heat-conducting plate 3 with screws. The type of temperature limiting element 5 is not limited. It can be an electronic temperature controller, such as an NTC thermistor electronic temperature controller, or a mechanical temperature controller, such as a snap-action mechanical temperature controller.

[0043] The first cover plate 1, the second cover plate 2, and the heat-conducting plate 3 are all made of metal. The first cover plate 1 and the second cover plate 2 are preferably made of stainless steel. The heat-conducting plate 3 is preferably made of pure aluminum or aluminum alloy, with a thermal conductivity of about 200-230 W / (m·K), which is higher than many other metals such as steel and copper, thus improving the thermal conductivity. The heating element 4 is preferably a heating tube with an S-shaped aluminum alloy shell, which increases the contact area with the heat-conducting plate 3 and enhances the thermal conductivity.

[0044] The method for manufacturing the heating device includes the following steps:

[0045] Step S1: Stamp the mating surface of the first cover plate 1 to form continuous protrusions 7, and select a second cover plate 2 that can be mated with the mating surface of the first cover plate 1.

[0046] Step S2: Clean and dry the surfaces of the first cover plate 1 and the second cover plate 2;

[0047] Step S3: Cover and press the first cover plate 1 and the second cover plate 2 together, and weld several weld points in sequence along the gap at the root of the straight section of the protrusion 7 toward its opening direction; then weld continuously along the gap and in the order of the weld points to form a gap weld; then take the end of the gap weld located at the opening of the gap as the weld point, and weld in sequence to form a closed circumferential weld around the protrusion 7.

[0048] Step S4: The heat-conducting plate 3 is attached to the side of the second cover plate 2 away from the chamber 9, and the heat-conducting plate 3 is welded and fastened to the second cover plate 2;

[0049] Step S5: The heating element 4 is attached to the side of the heat-conducting plate 3 away from the second cover plate 2, and the heating element 4 is welded and fastened to the heat-conducting plate 3;

[0050] Step S6: Surface treatment of the heating device formed in step S6.

[0051] In the above steps, the contact surface of the first cover plate 1 refers to the side that is in contact with the second cover plate 2. The contact surface of the first cover plate 1 is stamped to form a protrusion 7. At the same time, the first cover plate 1 can also be stamped to form a folded edge, which can help limit the second cover plate 2. In step S3, the top of the protrusion 7 is pressed, and the gap L1 between the roots of the adjacent straight sections of the protrusion 7 is spot welded from the inside to the outside by a laser beam. After the spot welding is completed, the weld point is positioned between the first cover plate 1 and the second cover plate 2. The laser beam can be used to weld along the weld point from the inner gap L1 to form a weld from the inside to the outside. One end of the weld is selected and welded to the outside to form a ring weld around the protrusion 7. The outer perimeter of the chamber 9 can be sealed by the ring weld. Combined with the extended weld extending into the gap L1, the adjacent straight sections of the protrusion 7 are separated to form a chamber 9 for fluid flow.

[0052] This method can effectively expel the air in the middle of the first cover plate 1 and the second cover plate 2. If the outer periphery of the protrusion 7 and the closed circumferential weld are welded first, the gap L1 part of the protrusion 7 is prone to bulging during subsequent welding, affecting the overall sealing of the weld.

[0053] In steps S4 and S5, the second cover plate 2, the heat-conducting plate 3, and the heating element 4 are all brazed to increase the contact area and improve the efficiency of heat transfer; in step S6, the surface treatment can be surface polishing or cleaning with a cleaning agent, whichever is required.

[0054] This low-cost heating device is achieved through simple spatial layout, structural coordination, and mature manufacturing process. This device can heat cold water and also turn cold water into steam.

[0055] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A heating device, characterized in that, The utility model relates to a heat -conducting plate and heating element combination, comprising: a first cover plate (1) provided with a continuous protrusion (7) with a bent section and a straight section; a second cover plate (2) attached to the opposite side of the first cover plate (1) opposite the protrusion (7) and covering the inner cavity of the protrusion (7) to form a chamber (9), the first cover plate (1) and the second cover plate (2) at the chamber (9) form a flow area for fluid flow, and the protrusion (7) is provided with a through hole (8) at both ends to communicate with the chamber (9); a ring edge weld joint welded on the first cover plate (1) and the second cover plate (2) and sealing the outside of the flow area; a gap weld joint welded on the gap between the adjacent straight sections of the protrusion (7) and connected to the ring weld joint at one end of the gap opening; and a heat-conducting plate (3) and a heating element (4) attached to the side of the second cover plate (2) away from the chamber (9) in sequence, and the heat generated by the heating element (4) is transmitted to the chamber (9) through the heat-conducting plate (3) and the second cover plate (2).

2. The heating device of claim 1, wherein The gap between the adjacent straight sections of the protrusion (7) is L1, and the value of L1 is 1-6 mm.

3. The heating device of claim 1, wherein, The cross section of the chamber (9) is trapezoidal, and the width gradually decreases in the direction away from the second cover plate (2).

4. The heating device of claim 1, wherein, The edge of the first cover plate (1) is bent and extends to cover the side edge of the second cover plate (2), forming a folded edge close to or / and attached to the side edge of the second cover plate (2).

5. The heating device of claim 1, wherein, The side of the heat-conducting plate (3) attached to the second cover plate (2) is provided with a plurality of fine grooves (10).

6. The heating device of claim 1, wherein, The side of the heat-conducting plate (3) facing the heating element (4) is provided with a plurality of stop points (11) abutting against the side edge of the heating element (4).

7. The heating device of claim 4, wherein The height of the folded edge is greater than the thickness of the second cover plate (2).

8. The heating device of claim 1, wherein, The shape of the heating element (4) is S-shaped, U-shaped, C-shaped or Z-shaped.

9. The heating device of claim 1, wherein, The first cover plate (1), the second cover plate (2) and the heat-conducting plate (3) are all made of hardware materials, the first cover plate (1) and the second cover plate (2) are made of stainless steel, the heat-conducting plate (3) is made of aluminum or aluminum alloy, and the heating element (4) is a heating tube with an aluminum alloy material shell.

10. The method of claim 1-9, wherein the heating device is made of a material selected from the group consisting of: metal, ceramic, glass, and plastic. The steps include: Step S1: stamping the attachment surface of the first cover plate (1) to form a continuous protrusion (7), and selecting a second cover plate (2) that can cover the attachment surface of the first cover plate (1); Step S2: cleaning and drying the surfaces of the first cover plate (1) and the second cover plate (2); Step S3: covering and pressing the first cover plate (1) and the second cover plate (2), sequentially welding and dotting along the gap between the straight section roots of the protrusion (7) towards the opening direction of the gap to form a plurality of weld points, then continuously welding along the gap and passing through the plurality of weld points in sequence according to the dotting order to form a gap weld joint, and then welding and forming a ring edge weld joint around the protrusion (7) and sealing the gap weld joint at the end of the gap weld joint located at the opening of the gap as a weld point; Step S4: attaching the heat-conducting plate (3) to the side of the second cover plate (2) away from the chamber (9), and welding and fastening the heat-conducting plate (3) to the second cover plate (2); Step S5: attaching the heating element (4) to the side of the heat-conducting plate (3) away from the second cover plate (2), and welding and fastening the heating element (4) to the heat-conducting plate (3).

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