Square coil panel

Abstract

The invention, which relates to the technical field of electromagnetic heating, discloses a square coil panel comprising a panel body which is square and has a heating surface and a supporting surface which are opposite to each other; the coil is arranged on the heating surface of the plate body; the shielding assembly comprises a first shielding part arranged on the heating surface and a second shielding part arranged on the supporting surface, and the first shielding part and the second shielding part are matched to shield magnetic lines generated by the coil and enable the magnetic lines to act on a heating target in a concentrated mode. According to the technical scheme provided by the invention, the technical problem that an existing coil panel cannot meet different heating requirements of a whole machine is solved.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic heating, in particular to a square coil disk. Background Art

[0002] Electromagnetic heating coils work based on the principle of electromagnetic induction. When alternating current passes through the coil, an alternating magnetic field is generated around it. When a conductive material is placed near the coil, the magnetic field generates eddy currents in the conductor, which cause energy loss due to the resistance of the eddy currents, thereby converting electrical energy into heat energy. During use, two or more coils are usually assembled in one complete machine, so that the two coils can be switched between each other during the heating process, or they can be bridged at the same time to adapt to pots of different shapes.

[0003] However, during use, the existing coil disk cannot meet the different requirements for heating the entire machine. Summary of the invention

[0004] The main purpose of the present invention is to provide a square coil disk, aiming to solve the technical problem that the existing coil disk cannot meet different requirements for heating the whole machine.

[0005] For the above purpose, the square coil disk proposed by the present invention comprises:

[0006] The plate body is square and has a heating surface and a supporting surface opposite to each other;

[0007] A coil, the coil being disposed on the heating surface of the disk; and

[0008] The shielding assembly includes a first shielding component arranged on the heating surface and a second shielding component arranged on the supporting surface. The first shielding component and the second shielding component cooperate to shield the magnetic lines of force generated by the coil and concentrate the magnetic lines of force on the heating target.

[0009] In one embodiment, the first shielding component includes a first magnetic strip and a second magnetic strip spaced from an outer layer of the heating surface to an inner layer of the heating surface, and the first magnetic strip and the second magnetic strip cooperate to shield the magnetic lines of force leaked circumferentially from the coil.

[0010] In one embodiment, at least one first magnetic strip is disposed on two adjacent sides of the disk body, and two adjacent first magnetic strips on the two sides are spaced apart; and / or,

[0011] Two adjacent sides of the disk body correspond to one of the second magnetic strips.

[0012] In one embodiment, at least two winding areas are spaced apart along the radial direction of the disk body, and each winding area corresponds to a coil, wherein the first magnetic strip is arranged on the outer periphery of one of the coils close to the edge of the disk body, and the second magnetic strip is arranged between two adjacent coils.

[0013] In one embodiment, the square coil disk further includes an isolation accessory, wherein one isolation accessory is provided between two adjacent coils, and the isolation accessory is provided with a magnetic stripe groove, and the second magnetic stripe is provided in the magnetic stripe groove.

[0014] In one embodiment, the second shielding component includes a third magnetic strip and a fourth magnetic strip arranged in sequence from the inner layer of the support surface to the outer layer of the support surface, and the fourth magnetic strip and the third magnetic strip cooperate to shield the magnetic lines of force leaked in the reverse direction of the coil.

[0015] In one embodiment, a plurality of the third magnetic strips are arranged at intervals along the circumferential direction of the disk body, and each corner of the disk body is correspondingly provided with one of the fourth magnetic strips.

[0016] In one embodiment, a through slot is provided at the center of the disk body, and one end of the third magnetic strip close to the through slot extends toward the heating surface to form a magnetic sealing protrusion, and each of the third magnetic strips is correspondingly provided with a magnetic sealing protrusion.

[0017] In one embodiment, the coil is fixed to the heating surface of the disk through electronic silicone; and / or,

[0018] The coil is fixed to the heating surface of the disk through resin oil.

[0019] In one embodiment, the square coil disk further includes heat-insulating cotton, which is disposed on a side of the coil away from the disk body to maintain a stable temperature of the coil.

[0020] In the technical solution provided by the present invention, a support function can be provided for the coil by means of a set disk body. The disk body is set in a square shape so that when two or more coil disks are spliced, the heating blind area between the coil disks can be reduced. The coil is arranged on the heating surface of the disk body, and is used to generate magnetic lines of force to achieve induction heating of the heating target. In addition, through the set shielding component, when it is necessary to heat the heating target, the first shielding component can shield the magnetic lines of force leaked circumferentially from the coil, and the second shielding component can shield the magnetic lines of force radiated toward the support surface. The coordinated use of the first shielding component and the second shielding component can effectively shield the magnetic lines of force generated by the coil, and radiate the magnetic lines of force in the opposite direction to the heating area, so that the magnetic lines of force can be more concentrated in the plane area of ​​the coil disk, thereby concentrating the energy of the magnetic lines of force and reducing the energy leakage loss of the magnetic lines of force. The technical solution proposed in the embodiment of the present invention replaces the traditional circular coil disk with a square coil disk, which can reduce the heating blind area between the coil disks when two or more coil disks are spliced ​​and achieve a bridging function. The cookware can be heated by placing it on the coil disk or between two coil disks, thereby improving the consumer experience. In addition, a shielding component is set to reduce the leakage loss of magnetic lines of the square coil disk during operation, thereby improving the heating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the structure of an embodiment of a square coil disk provided by the present invention Figure 1 ;

[0023] Figure 2 A schematic diagram of the structure of an embodiment of a square coil disk provided by the present invention Figure 2 ;

[0024] Figure 3 A schematic structural diagram of another perspective of an embodiment of a square coil disk provided by the present invention.

[0025] Description of Figure Numbers:

[0026] 10. disk body; 20. coil; 30. shielding assembly; 31. first shielding component; 311. first magnetic strip; 312. second magnetic strip; 32. second shielding component; 321. third magnetic strip; 3211. magnetic sealing protrusion; 322. fourth magnetic strip; 40. isolation accessories; 50. thermal insulation cotton.

[0027] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiment is only a component embodiment of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0031] For the coil discs used for electromagnetic heating, two or more coil discs are usually installed in one complete machine during use, so that the two discs can be switched between each other during the heating process, or can be bridged to work at the same time to adapt to pots of different shapes. However, there is a large heating blind area between the two traditional round discs, and the existing square coils will leak magnetic lines during operation and testing, causing losses, and cannot meet the first-level energy efficiency standards and meet different heating requirements for the whole machine.

[0032] In view of this, an embodiment of the present invention provides a square coil disk, in which the disk body is set to a square shape to reduce the heating blind area, a first shielding component is set on the heating surface of the disk body, and a second shielding component is set on the supporting surface of the disk body, so that through the cooperation of the first shielding component and the second shielding component, the leaked magnetic lines of force are concentrated on the heating target, thereby reducing energy loss and improving the heating efficiency of the whole machine.

[0033] In order to better understand the above technical solution, the above technical solution is described in detail below with reference to the accompanying drawings.

[0034] like Figure 1 , Figure 2 , Figure 3 As shown, the present invention provides a square coil disk, comprising:

[0035] For the above purpose, the square coil disk proposed by the present invention comprises:

[0036] The tray body 10 is square and has a heating surface and a supporting surface opposite to each other;

[0037] The coil 20 is disposed on the heating surface of the plate 10; and

[0038] The shielding assembly 30 includes a first shielding component 31 disposed on the heating surface and a second shielding component 32 disposed on the supporting surface. The first shielding component 31 and the second shielding component 32 cooperate to shield the magnetic lines of force generated by the coil 20 and concentrate the magnetic lines of force on the heating target.

[0039] In the technical solution adopted in this embodiment, the set disk body 10 can provide support for the coil 20. The disk body 10 is set in a square shape so that when two or more coil disks are spliced, the heating blind area between the coil disks can be reduced. The coil 20 is arranged on the heating surface of the disk body 10 to generate magnetic lines of force to achieve induction heating of the heating target. In addition, through the set shielding component 30, when it is necessary to heat the heating target, the first shielding component 31 can shield the magnetic lines of force leaked circumferentially from the coil 20, and the second shielding component 32 can shield the magnetic lines of force radiated toward the support surface. The coordinated use of the first shielding component 31 and the second shielding component 32 can effectively shield the magnetic lines of force generated by the coil 20, and radiate the magnetic lines of force in the opposite direction to the heating area, so that the magnetic lines of force can be more concentrated in the plane area of ​​the coil disk, thereby concentrating the energy of the magnetic lines of force and reducing the energy leakage loss of the magnetic lines of force. The technical solution proposed in the embodiment of the present invention replaces the traditional circular coil disk with a square coil disk, which can reduce the heating blind area between the coil disks when two or more coil disks are spliced ​​and achieve a bridging function. The cookware can be heated by placing it on the coil disk or between two coil disks, thereby improving the consumer experience. In addition, the shielding component 30 is set to reduce the leakage loss of the magnetic field lines of the square coil disk during operation, thereby improving the heating efficiency.

[0040] Specifically, the square coil disk includes a disk body 10, a coil 20 and a shielding assembly 30. The disk body 10 can be made of plastic or resin material, a material with excellent heat resistance and good insulation performance, and has a certain mechanical strength, which can provide support. The coil 20 is a flattened coil 20 with multiple strands of fine wires tightly wound, which can enhance the electromagnetic performance of the coil 20, thereby improving the inductance performance of the coil 20, and can improve the thermal stability of the coil 20, so that the magnetic field generated by the current is more uniform, and the risk of local overheating is reduced. The shielding assembly 30 includes a first shielding component 31 arranged on the heating surface and a second shielding component 32 arranged on the supporting surface, which are used to shield the magnetic lines of force leaked from the coil 20 toward the non-heating area, thereby concentrating the energy of the magnetic lines of force and reducing the energy loss of the magnetic lines of force. It can be understood that the first shielding component 31 can shield the magnetic lines of force leaked toward the edge of the heating surface, and the second shielding component 32 can shield the magnetic lines of force leaked toward the supporting surface in the opposite direction. In this embodiment, two or more coil disks can be installed in a complete machine, and the disk body 10 is set to be square, so that the two coil disks can switch between each other during the heating process, and can also work as a bridge at the same time, and can ensure that when the cookware is placed between two of the coils 20, the heating blind area between the coil disks is smaller.

[0041] Further, see Figure 2 In one embodiment of the present invention, the first shielding component 31 includes a first magnetic strip 311 and a second magnetic strip 312 spaced from the outer layer of the heating surface to the inner layer of the heating surface, and the first magnetic strip 311 and the second magnetic strip 312 cooperate to shield the magnetic lines of force leaked circumferentially from the coil 20.

[0042] In the technical solution adopted in this embodiment, the first shielding component 31 may include a first magnetic stripe 311 and a second magnetic stripe 312. In this embodiment, the inner layer and the outer layer of the heating surface are distinguished along the diagonal direction of the square disk body 10, wherein the inner layer is close to the center of the square disk body 10, and the outer layer is close to the edge of the square disk body 10. The first magnetic stripe 311 is arranged on the side of the coil 20 close to the edge of the square disk body 10 to shield the magnetic lines of force leaking toward the outside of the square disk body 10. The second magnetic stripe 312 is arranged on the side of the coil 20 close to the center of the square disk body 10 to shield the magnetic lines of force leaking toward the center of the square disk body 10. The first magnetic stripe 311 and the second magnetic stripe 312 are used together to reduce the magnetic lines of force leaking circumferentially, thereby enhancing the heating effect of the magnetic field generated by the coil 20. In addition, the influence of the magnetic field of the coil 20 on the surroundings can be reduced, and the interference of the external magnetic field on the internal magnetic field of the coil 20 can also be reduced.

[0043] Further, see Figure 2 In one embodiment of the present invention, at least one first magnetic strip 311 is respectively disposed on two adjacent sides of the disk body 10, and the two adjacent first magnetic strips 311 on the two sides are arranged at intervals; and / or,

[0044] Two adjacent sides of the disk body 10 correspond to a second magnetic strip 312 .

[0045] In the technical solution adopted in this embodiment, the first magnetic stripe 311 and the second magnetic stripe 312 are both irregular geometric shapes, wherein the first magnetic stripe 311 has a first portion and a second portion connected, the first portion is parallel to the side of the coil 20, and the second portion is consistent with the contour of the outer corner of the coil 20. The second magnetic stripe 312 has a first arc edge and a second arc edge connected end to end, the curvature of the second arc edge is greater than the first arc edge, and the first arc edge is consistent with the contour of the inner corner of the coil 20. By such a setting, the magnetic lines of force can be better shielded and concentrated, so that the magnetic lines of force act on the heating target.

[0046] Further, see Figure 2 In one embodiment of the present invention, at least two winding areas are spaced apart along the radial direction of the disk body 10, and each winding area corresponds to a coil 20, wherein a first magnetic strip 311 is arranged on the outer periphery of a coil 20 close to the edge of the disk body 10, and a second magnetic strip 312 is arranged between two adjacent coils 20.

[0047] In the technical solution adopted in this embodiment, by such an arrangement, the double-loop or multi-loop coil 20 provides a more uniform magnetic field distribution to enhance the electromagnetic performance. In the following description, the double-loop coil 20 is introduced. In this embodiment, the first magnetic strip 311 is used to shield the magnetic field lines around the outer ring coil 20. The second magnetic strip 312 is arranged between the outer ring coil 20 and the inner ring coil 20, which can reduce the electromagnetic interference between the outer ring coil 20 and the inner ring coil 20, wherein the first arc edge of the second magnetic strip 312 is consistent with the contour of the inner corner of the outer ring coil 20, and the second arc edge of the second magnetic strip 312 is consistent with the outer contour of the inner ring coil 20.

[0048] Further, see Figure 2 In one embodiment of the present invention, the square coil disk further includes an isolation accessory 40, an isolation accessory 40 is provided between two adjacent coils 20, and the isolation accessory 40 is provided with a magnetic stripe groove, and the second magnetic stripe 312 is provided in the magnetic stripe groove.

[0049] In the technical solution adopted in this embodiment, the direction coil disk may further include an isolation accessory 40. The isolation accessory 40 is fixed on the disk body 10 by extrusion between the outer ring coil 20 and the inner ring coil 20. In this embodiment, the isolation accessory 40 is set to be square, and each corner of the isolation accessory 40 is provided with a magnetic strip groove consistent with the outer contour of the second magnetic strip 312 for accommodating the second magnetic strip 312. In this way, the magnetic lines of force generated by the coil 20 can be effectively concentrated to reduce interference and leakage between the magnetic lines of force.

[0050] Further, see Figure 3 In one embodiment of the present invention, the second shielding component 32 includes a third magnetic strip 321 and a fourth magnetic strip 322 which are arranged in sequence from the inner layer of the supporting surface to the outer layer of the supporting surface. The fourth magnetic strip 322 and the third magnetic strip 321 cooperate to shield the magnetic lines of force leaked in the reverse direction of the coil 20.

[0051] In the technical solution adopted in this embodiment, the second shielding component 32 may include a third magnetic stripe 321 and a fourth magnetic stripe 322. In this embodiment, the inner layer of the support surface is close to the central axis of the support surface, and the outer layer of the support surface is close to the corner of the support surface. The third magnetic stripe 321 covers most of the support surface to shield the magnetic lines of force toward the support surface and radiate in the opposite direction to act on the heating target. The fourth magnetic stripe 322 covers the corner of the support surface to shield the magnetic lines of force in the blind area not covered by the third magnetic stripe 321, thereby improving the uniformity of electromagnetic heating. The third magnetic stripe 321 and the fourth magnetic stripe 322 are used together to reduce the magnetic lines of force that leak in the reverse direction, thereby enhancing the strength of the central magnetic lines of force, increasing the central temperature, making the temperature more uniform, and having a better heating effect.

[0052] Further, see Figure 3 In one embodiment of the present invention, a plurality of third magnetic strips 321 are arranged at intervals along the circumferential direction of the disk body 10, and a fourth magnetic strip 322 is correspondingly provided at each corner of the disk body 10.

[0053] In the technical solution adopted in this embodiment, the third magnetic stripe 321 and the fourth magnetic stripe 322 are both irregular geometric shapes, wherein the third magnetic stripe 321 has a first end and a second end opposite to each other, and a plurality of third magnetic stripes 321 are sequentially arranged along the circumferential direction of the disk body 10, so that the first ends of the plurality of third magnetic stripes 321 form an inner circle, and the second ends of the plurality of third magnetic stripes 321 form an outer circle. The fourth magnetic stripe 322 has a first outer contour and a second outer contour connected end to end, the first outer contour is consistent with the corner shape of a coil 20 close to the edge of the disk body 10, and the second outer contour is consistent with the arc of the outer circle formed by the second ends of the plurality of third magnetic stripes 321. By such an arrangement, the circular shielding structure composed of the plurality of third magnetic stripes 321 can enhance the structural stability of the coil disk and extend the service life, and a fourth magnetic stripe 322 is correspondingly arranged at each corner of the disk body 10, which can reduce the leakage of magnetic lines of force and improve the airtightness of the shielding.

[0054] Further, see Figure 2 , Figure 3 In one embodiment of the present invention, a through slot is provided at the center of the disk body 10, and one end of the third magnetic strip 321 close to the through slot extends toward the heating surface to form a magnetic sealing protrusion 3211, and each third magnetic strip 321 is correspondingly provided with a magnetic sealing protrusion 3211.

[0055] In the technical solution adopted in this embodiment, the magnetic sealing protrusion 3211 is provided to concentrate the magnetic lines of force generated by the coil 20, reduce the diffusion of the magnetic lines of force in the non-heating area, and thus improve the heating efficiency and uniformity. In this embodiment, the magnetic sealing protrusion 3211 extends through the through slot to the heating surface, and can also have a certain reinforcement effect on the third magnetic strip 321.

[0056] Further, in one embodiment of the present invention, the coil 20 is fixed to the heating surface of the disk 10 by electronic silicone; and / or,

[0057] The coil 20 is fixed to the heating surface of the plate 10 by resin oil.

[0058] In the technical solution adopted in this embodiment, the coil 20 can be fixed to the heating surface of the disk body 10 by electronic silicone or resin oil. Both electronic silicone and resin oil have good adhesive properties, which can ensure that the coil 20 is firmly fixed on the heating surface of the disk body 10, reducing the displacement caused by vibration or thermal expansion. And it also has good insulation performance, which can reduce the risk of circuit short circuit and damage to electrical components, and improve the safety of the equipment. In addition, if the coil 20 needs to be repaired or replaced, the coil 20 fixed with electronic silicone or resin oil is easier to disassemble, which is convenient for maintenance operations. In this embodiment, the coil 20 is a multi-strand fine wire tightly wound flattened coil 20. Through the fixing method of electronic silicone or resin oil, the wire diameter and winding area of ​​the enameled wire can be reasonably configured, and the various special-shaped magnetic strips in the shielding assembly 30 are arranged in coordination, so that all the magnetic lines of force are concentrated on the heating target, reducing the leakage of magnetic lines of force. At the same time, a corresponding electric control solution can be matched to reduce losses, so that the thermal efficiency can reach or even exceed the national standard first-level energy efficiency. During assembly, a square isolation accessory 40 or a clamp is used for isolation, and the clamp is removed after the coil 20 is shaped to ensure that the wound coil 20 finally appears to be square.

[0059] Further, see Figure 1 In one embodiment of the present invention, the square coil disk further includes a heat preservation cotton 50, which is disposed on the side of the coil 20 away from the disk body 10 to keep the temperature of the coil 20 stable.

[0060] In the technical solution adopted in this embodiment, the temperature can be reduced by thirty by setting the thermal insulation cotton 50, thereby improving the energy utilization rate. The thermal insulation cotton 50 can be fixed on the surface of the coil 20 by a structure or by adhesive, and the specific fixing method is not limited here. The thermal insulation cotton 50 should be selected according to the temperature resistance grade of the material, and needs to have sufficient temperature resistance and flame retardant properties. In addition, in order to ensure safety, the condition of the coil 20 and the thermal insulation cotton 50 should also be checked regularly.

[0061] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A square coil disk, characterized in that: include: The plate body is square and has a heating surface and a supporting surface opposite to each other; A coil, the coil being arranged on the heating surface of the disk; as well as The shielding assembly includes a first shielding component arranged on the heating surface and a second shielding component arranged on the supporting surface. The first shielding component and the second shielding component cooperate to shield the magnetic lines of force generated by the coil and concentrate the magnetic lines of force on the heating target.

2. The square coil disk according to claim 1, characterized in that The first shielding component includes a first magnetic strip and a second magnetic strip spaced from the outer layer of the heating surface to the inner layer of the heating surface, and the first magnetic strip and the second magnetic strip cooperate to shield the magnetic lines of force leaked in the circumferential direction of the coil.

3. The square coil disk according to claim 2, characterized in that At least one first magnetic strip is respectively disposed on two adjacent sides of the disk body, and two adjacent first magnetic strips on the two sides are spaced apart; and / or, Two adjacent sides of the disk body correspond to one of the second magnetic strips.

4. The square coil disk according to claim 2, characterized in that At least two winding areas are arranged at intervals along the radial direction of the disk body, and each winding area corresponds to a coil, wherein the first magnetic strip is arranged on the outer periphery of one of the coils close to the edge of the disk body, and the second magnetic strip is arranged between two adjacent coils.

5. The square coil disk according to claim 4, characterized in that The square coil disk also includes an isolation accessory, one of which is provided between two adjacent coils, and the isolation accessory is provided with a magnetic stripe groove, and the second magnetic stripe is arranged in the magnetic stripe groove.

6. The square coil disk according to claim 1, characterized in that The second shielding component includes a third magnetic strip and a fourth magnetic strip arranged in sequence from the inner layer of the support surface to the outer layer of the support surface, and the fourth magnetic strip and the third magnetic strip cooperate to shield the magnetic lines of force leaked in the reverse direction of the coil.

7. The square coil disk according to claim 4, characterized in that A plurality of the third magnetic strips are arranged at intervals along the circumferential direction of the disk body, and each corner of the disk body is correspondingly provided with one of the fourth magnetic strips.

8. The square coil disk according to claim 7, characterized in that A through slot is provided at the center of the disk body, and one end of the third magnetic strip close to the through slot extends toward the heating surface to form a magnetic sealing protrusion, and each of the third magnetic strips is correspondingly provided with a magnetic sealing protrusion.

9. The square coil disk according to claim 1, characterized in that The coil is fixed to the heating surface of the disk through electronic silicone; and / or, The coil is fixed to the heating surface of the disk through resin oil.

10. The square coil disk according to claim 1, characterized in that The square coil disk also includes heat-insulating cotton, which is arranged on the side of the coil away from the disk body to keep the temperature of the coil stable.

Images