Coil panel assembly and electromagnetic heating device

Abstract

The utility model discloses a coil panel assembly and an electromagnetic heating device, and relates to the technical field of electromagnetic heating, the coil panel assembly comprises a support and at least two winding units which are distributed adjacently along the circumferential direction of the support, the winding centers of the two winding units deviate towards the edge of the support relative to the geometric centers of the winding units, and the winding centers of the two winding units are arranged adjacently along the circumferential direction of the support. When the two winding units are powered on, magnetic poles which are adjacent to the edge of the support and opposite in magnetism are formed, a closed magnetic field is formed between the two winding units, the magnetic field can be coupled with the position corresponding to the pot wall from the side close to the edge of the support, and the heating uniformity of the pot bottom and the pot wall is improved. The installation side of the support is gradually arranged in a protruding mode in the direction of one side from the middle to the periphery, so that the two winding units are attached to the pot bottom and the pot wall to the maximum extent, the positions of the pot bottom and the pot wall can obtain the magnetic field intensity as high as possible, and the problem that an existing induction cooker is poor in temperature rising efficiency of the pot wall of a frying pot is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of electromagnetic heating, and particularly relates to a coil disc assembly and an electromagnetic heating device. Background Art

[0002] During the stir-frying process, the bottom of the cookware cools down quickly due to the convergence of soup, which will significantly reduce the bottom of the pot to a relatively low temperature and fail to reach the relatively high temperature required for stir-frying; while for the pot wall part, there is no cooling problem caused by soup. As long as there is a relatively high heating power density, it can maintain the relatively high temperature required for stir-frying. The cooking surface of an ordinary induction cooker (or stove) is flat. The distance between the pot wall of the frying pan and the cooking surface is far. Therefore, when the alternating magnetic field generated by the coil disc arranged under the cooking surface reaches the position of the pot wall, the intensity is low and the heating power density is small, making it difficult to increase the temperature of the pot wall, and the stir-frying effect is poor.

[0003] In the prior art, the cooking surface of an ordinary concave induction cooker is set to be basically in the shape that fits the outer shape of the cookware, and the coil disc arranged under the cooking surface is also set to be a corresponding concave shape. Therefore, the distance between the pot wall and the coil disc is greatly reduced, and the magnetic field intensity in the pot wall area is greatly increased. The heating power density, temperature, and stir-frying effect are all significantly improved. However, in an ordinary concave induction cooker, the coil disc generally uses a conventional spiral winding method, and the peak value of the magnetic field intensity is generally distributed in an annular area with a diameter of about 1 / 3. When matching with the cookware, the position of the annular area corresponding to the center of the cookware is still relatively close to the bottom of the cookware, and it still cannot reach the height of the high-temperature area of the pot wall generated by a gas stove, so that the stir-frying experience and effect are still worse than those of a gas stove. Summary of the Utility Model

[0004] The main object of the utility model is to propose a coil disc assembly and an electromagnetic heating device, aiming to solve the problem of poor efficiency in increasing the temperature of the pot wall of a frying pan by an existing induction cooker.

[0005] To achieve the above object, the coil disc assembly proposed by the utility model includes:

[0006] A bracket, the bracket has opposite first and second sides, one of the first side or the second side of the bracket is set as the installation side, and the installation side protrudes gradually from the middle to the surrounding in the direction of the first side; and,

[0007] At least two winding units are arranged on the installation side of the bracket. The two winding units are arranged adjacent to each other along the circumferential direction of the bracket, and the winding centers of the two winding units deviate from their geometric centers towards the edge of the bracket, so that when the two winding units are energized, magnetic poles adjacent to the edge of the bracket are formed, and the magnetic poles of the two winding units are opposite in magnetism.

[0008] In one embodiment, each of the winding units is arranged in a ring shape, having a first winding ring segment close to the center of the bracket and a second winding ring segment close to the edge of the bracket;

[0009] In the two winding units, the current directions of the two winding units are set to be opposite, so that opposite magnetic poles are formed in the middle of the two winding units. And in at least one of the winding units, the width of the first winding ring segment is d1, and the width of the second winding ring segment is d2, where d1 > d2.

[0010] In one embodiment, each of the winding units is arranged in a ring shape, and the first winding ring segment and the second winding ring segment are located on the mounting side of the bracket.

[0011] In one embodiment, in the depth direction of the mounting side of the bracket, the distance d from the outer peripheral edge of the plurality of winding units to the bottom is d ≥ 5 mm.

[0012] In one embodiment, the first side of the bracket is set as the mounting side, and the first winding ring segment is arranged on the mounting side;

[0013] The second winding ring segment is turned over to the other side of the first winding ring segment, so that the second winding ring segment is located on the second side of the bracket.

[0014] In one embodiment, the coil disc assembly further includes a shielding structure arranged on the side of the winding unit facing the bracket.

[0015] In one embodiment, the shielding structure includes a plurality of first magnetic strips arranged at intervals along the circumferential direction of the bracket. Each of the first magnetic strips extends outward from the middle of the bracket and is arranged in a curved shape adapted to the first winding ring segment.

[0016] In one embodiment, the shielding structure includes a plurality of second magnetic strips arranged at intervals, and the plurality of second magnetic strips are arranged along a concave surface shape adapted to the first winding ring segment.

[0017] The present invention also provides an electromagnetic heating device, including a coil disc assembly, and the coil disc assembly includes:

[0018] A bracket having opposite first and second sides. The first side or the second side of the bracket is set as the mounting side, and the mounting side protrudes gradually from the middle to the periphery in the direction of the first side; and,

[0019] At least two winding units are arranged on the mounting side of the bracket. The two winding units are distributed adjacently along the circumferential direction of the bracket. The winding centers of the two winding units are offset towards the edge of the bracket compared to their geometric centers, so that when the two winding units are energized, magnetic poles adjacent to the edge of the bracket are formed, and the magnetic poles of the two winding units have opposite magnetic polarities.

[0020] In one embodiment, the electromagnetic heating device further includes a housing for mounting the coil disc assembly. The housing includes a panel, and at least a part of the panel is arranged in a concave shape so as to be at least correspondingly arranged with the first winding ring segment.

[0021] In the technical solution provided by the present utility model, the mounting side of the bracket protrudes gradually from the middle to the periphery towards one side thereof, so that the two winding units are as close as possible to the bottom and the wall of the pot, thereby enabling the positions of the bottom and the wall of the pot to obtain as large a magnetic field intensity as possible. Among the at least two winding units arranged along the circumferential direction of the bracket and distributed adjacently on the bracket, the winding centers of the two winding units are offset towards the edge of the bracket compared to their geometric centers. When the two winding units are energized, magnetic poles adjacent to the edge of the bracket and having opposite magnetic polarities are formed. A closed magnetic field is formed between the two winding units, and the magnetic field can couple with the position of the corresponding pot wall starting from the side close to the edge of the bracket, improving the uniformity of heating of the bottom and the wall of the pot, so as to solve the problem that the existing induction cooker has a poor efficiency in increasing the temperature of the wall of a frying pan. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the structures shown in these drawings.

[0023] Figure 1 It is a schematic plan view of an embodiment of the coil disc assembly provided by the present utility model;

[0024] Figure 2 For Figure 1 a schematic diagram of the cross-section of the coil disc assembly and the cookware in

[0025] Figure 3 For Figure 1 a schematic diagram of the induction magnetic field direction between the cookware and the coil disc assembly in

[0026] Figure 4 For Figure 1 a schematic diagram of A - A in

[0027] Figure 5 is Figure 4 a schematic diagram of the depth direction of the middle winding unit;

[0028] Figure 6 is Figure 1 an exploded schematic diagram of the coil disc assembly of ;

[0029] Figure 7 is a schematic diagram of the planar structure of another embodiment of the coil disc assembly provided by the present utility model;

[0030] Figure 8 is Figure 7 a schematic diagram of B-B in ;

[0031] Figure 9 is Figure 7 an exploded schematic diagram of the coil disc assembly of ;

[0032] Figure 10 is Figure 1 a schematic diagram of the magnetic field formed by two adjacent winding units in ;

[0033] Figure 11 is an exploded schematic diagram of an embodiment of the electromagnetic heating device provided by the present utility model.

[0034] Explanation of the reference numerals in the drawings:

[0035] 100, coil disc assembly; 1, bracket; 2, winding unit; 21, first winding ring segment; 22, second winding ring segment; 3, shielding structure; 31, first magnetic strip;

[0036] 200, cookware; 201, bottom of the pot; 202, pot wall;

[0037] 300, electromagnetic heating device; 4, housing; 41, panel.

[0038] The realization, functional features and advantages of the purpose of the present utility model will be further described with reference to the embodiments and the accompanying drawings. Specific embodiments

[0039] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts shall fall within the protection scope of the present utility model.

[0040] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present utility model, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain specific posture (as shown in the attached drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0041] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present utility model, then such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0042] In the prior art, the cooking surface of a common concave induction cooker is set to a shape that basically fits the outer shape of the cookware, and the coil disk arranged below the cooking surface is also set to a corresponding concave shape. Therefore, the distance between the pot wall and the coil disk is greatly reduced, the magnetic field intensity in the pot wall area is greatly increased, and the heating power density, temperature, and stir-frying effect are all significantly improved. However, in a common concave induction cooker, the coil disk generally uses a conventional spiral winding method, and the peak value of the magnetic field intensity is generally distributed in an annular area with a diameter of about 1 / 3. When matching with the cookware, the position of the annular area corresponding to the center of the cookware is still at a position relatively close to the bottom of the cookware, and it still cannot reach the height of the high-temperature area on the pot wall generated by a gas stove, so that the cooking experience and effect are still worse than those of a gas stove.

[0043] To solve this technical problem, the present utility model provides a coil disk assembly 100 to solve the problem of poor temperature elevation efficiency of the pot wall of a frying pan in an existing induction cooker.

[0044] Please refer to Figures 1 to 3 , the coil disk assembly 100 includes a bracket 1 and at least two winding units 2. The bracket 1 has opposite first and second sides. One of the first side or the second side of the bracket 1 is set as the installation side, and the installation side protrudes gradually from the middle to the surrounding in the direction of the first side. The two winding units 2 are arranged on the installation side of the bracket 1. The multiple winding units 2 are distributed adjacent to each other along the circumferential direction of the bracket 1. The winding centers of the two winding units 2 deviate from their geometric centers towards the edge of the bracket 1, so that when the two winding units 2 are energized, magnetic poles adjacent to the edge of the bracket 1 are formed, and the magnetic poles of the two winding units 2 have opposite magnetic polarities.

[0045] It should be noted that in the prior art, the conventional coil disk is set as an annular spiral winding structure, and the winding gaps between two adjacent turns are uniform and the same. When the conventional coil disk is coupled with the cookware 200, especially the cookware 200 of the wok type, due to the limitation of the shape characteristics of the wok, the side wall of the cookware 200 is far from the bottom, and the corresponding magnetic field density of the coil disk where it is located is small, resulting in low heating efficiency.

[0046] It can be understood that since the installation side of the bracket 1 protrudes gradually from the middle to the periphery in the direction of the first side, the bracket 1 thus forms a concave structure, and the winding unit 2 installed on the bracket 1 forms a concave surface that can be adapted to the bottom of the wok, so that the two winding units are closest to the bottom and the pot wall to the greatest extent.

[0047] It should be pointed out that the shapes of the winding units 2 in the "multiple winding units 2" described in this application can be set to be the same or different. Each winding unit 2 is formed by winding multiple turns of coils. Each turn of coil in each winding unit 2 can be regarded as an annular structure. Of course, the annular structure is not only limited to a circular shape, it can be square, or oval, or even of a special shape.

[0048] "The multiple winding units 2 are distributed adjacently along the circumferential direction of the bracket 1" can be that the multiple winding units 2 are distributed in a ring shape on the same side of the bracket 1, or part of the winding units 2 are arranged on one side of the bracket 1 and the other part of the winding units 2 are arranged on the other side of the bracket 1. However, as long as they are distributed in a ring shape on the projection plane of the bracket 1, they can be regarded as "the multiple winding units 2 are distributed adjacently along the circumferential direction of the bracket 1".

[0049] When the two winding units 2 are energized, magnetic poles adjacent to the edge of the bracket 1 are formed, and the magnetic poles of the two winding units 2 have opposite magnetic polarities. According to Ampere's rule: Hold the energized solenoid with the right hand and let the four fingers point in the direction of the current, then the end pointed by the thumb is the N pole of the energized solenoid. Thus, please refer to Figure 10, one of the two winding units 2 is set as the first winding unit, and the other is set as the second winding unit. When the first winding unit and the second winding unit are arranged flat on the installation side of the bracket 1 extending in the horizontal direction, that is, when the N pole of the magnetic pole is formed on the upper side of the first winding unit and the S pole is formed on the lower side, at the same time, the S pole of the magnetic pole is formed on the upper side of the second winding unit and the N pole is formed on the lower side; thus, the magnetic field lines go from the N pole of the first winding unit to the S pole of the second winding unit, then from the S pole of the second winding unit to the N pole, then from the N pole of the second winding unit to the S pole of the first winding unit, and then from the S pole of the first winding unit back to the N pole of the first winding unit, thereby forming a closed magnetic field. Moreover, the magnetic poles formed by each winding unit 2 are arranged close to the edge of the bracket 1, and the magnetic field can interact with the pot wall far from the winding unit 2 in as large a range as possible to realize the heating of the pot wall.

[0050] In the technical solution provided by the present utility model, the installation side of the bracket protrudes gradually from the middle to the surrounding in the direction of one side thereof, so that the two winding units are closest to the bottom and the pot wall to the greatest extent, so that the magnetic field intensity can be obtained as large as possible at the positions of the bottom and the pot wall. Among at least two winding units arranged along the circumferential direction of the bracket and adjacent to each other, the winding centers of the two winding units deviate from the geometric center towards the edge of the bracket. When the two winding units are energized, magnetic poles with opposite polarities adjacent to the edge of the bracket are formed, and a closed magnetic field is formed between the two winding units. The magnetic field can be coupled with the corresponding pot wall position starting from the side close to the edge of the bracket, improving the uniformity of heating of the bottom and the pot wall to solve the problem of poor temperature increase efficiency of the pot wall of the frying pan by the existing induction cooker.

[0051] In this embodiment, each winding unit 2 is arranged in a ring shape, which has a first winding ring section 21 close to the center of the bracket 1 and a second winding ring section 22 close to the edge of the bracket 1; in the two winding units 2, the current directions of the two winding units 2 are set to be opposite so that opposite magnetic poles are formed in the middle of the two winding units 2. And in at least one winding unit 2, the width of the first winding ring section 21 is d1, and the width of the second winding ring section 22 is d2, where d1 > d2.

[0052] It should be noted that the "current direction" refers to the flow direction of the current in the winding unit 2 along the clockwise or counterclockwise direction. "The current directions of the two winding units 2 are set to be opposite" means that when the current direction of one winding unit 2 is clockwise, the current direction of the other winding unit 2 is counterclockwise.

[0053] It should be noted that "d1 > d2" may mean that when the windings of the first winding loop segment 21 and the second winding loop segment 22 are arranged such that the adjacent winding line segments in each winding loop segment are arranged in parallel, the winding gap of the first winding loop segment 21 is set to be greater than the winding gap of the second winding loop segment 22. Of course, when the adjacent winding line segments in each winding loop segment are not arranged in parallel, it will cause the winding gap to be uneven, but other partial winding line segments can be adjusted adaptively to finally achieve d1 > d2. Overall, the magnetic field density of the second winding loop segment 22 is higher than that of the first winding loop segment 21. Of course, the specific manner of setting the width of the first winding loop segment 21 to be greater than the width of the second winding loop segment 22 is not limited to the above examples. Those skilled in the art may make other changes under the inspiration of the technical essence of the embodiments of this specification, but as long as the functions and effects achieved are the same or similar to those of the embodiments of this specification, they should all be covered within the protection scope of the embodiments of this specification.

[0054] In the embodiments of the present utility model, each of the winding units 2 is arranged in a ring shape, and both the first winding loop segment 21 and the second winding loop segment 22 are located on the installation side of the bracket 1. In this way, the heating surface of the coil disc assembly 100 is larger, and it can heat a higher position of the pot wall 202. Moreover, when processing the coil disc and winding the winding unit 2, it only needs to be wound on the installation side of the bracket 1, which is convenient for processing.

[0055] In the embodiments of the present utility model, in the depth direction of the installation side of the bracket, the distance d from the outer periphery of the plurality of winding units 2 to the bottom is d ≥ 5 mm. By setting d to be greater than or equal to 5 mm, the radian of the winding unit 2 can adapt to the radian of most frying pans, avoiding the situation where when the radian is too small, the effect of fitting with the pot wall 202 of the cooking utensil 200 still cannot be achieved.

[0056] In the embodiments of the present utility model, the first side of the bracket 1 is set as the installation side, and the first winding loop segment 21 is arranged on the installation side of the bracket 1; the second winding loop segment 22 is arranged to be folded over to the other side of the first winding loop segment 21, so that the second winding loop segment 22 is located on the second side of the bracket 1.

[0057] By arranging the second winding loop segment 22 on the other side of the bracket 1 away from the first winding loop segment 21, it is avoided that the volume of the coil disc assembly 100 is too large. In the case of a size similar to that of a common induction cooker, the second winding loop segment 22 can produce a better heating effect on the pot wall 202.

[0058] Furthermore, in an embodiment of the present utility model, the coil disk assembly 100 further includes a shielding structure 3 disposed on one side of the winding unit facing the bracket 1. Thus, by providing the shielding structure 3 with good magnetic permeability, it is beneficial to concentrate magnetic lines of force, improve the heating power and heating efficiency of the coil disk assembly 100. At the same time, it can isolate the coil magnetic field for the electronic components disposed below the coil disk assembly 100 to ensure the reliability of the electronic components. When the induction cooker having the coil disk assembly 100 is used on a metal tabletop, it can prevent the magnetic field below from heating the metal tabletop at the bottom of the induction cooker.

[0059] In an embodiment of the present utility model, the shielding structure 3 includes a plurality of first magnetic strips 31 arranged at intervals along the circumferential direction of the bracket 1. Each of the first magnetic strips 31 extends outward from the middle of the bracket 1 and is arranged in a curved shape adapted to the first winding ring segment 21. By directly providing a curved magnetic strip adapted to the first winding ring segment, it is more convenient during the assembly process, improving the assembly efficiency. Moreover, compared with the splicing of multiple magnetic strips, the gap between the plurality of first magnetic strips 31 is smaller, and the magnetic leakage prevention effect is better.

[0060] Specifically, in another embodiment of the present utility model, the shielding structure 3 includes a plurality of second magnetic strips arranged at intervals. The plurality of second magnetic strips are arranged along a concave surface shape adapted to the first winding ring segment 21. Each of the second magnetic strips can be set as an ordinary straight magnetic strip. The plurality of second magnetic strips are arranged at intervals and are arranged along the concave surface of the first winding ring segment 21 to form a concave surface adapted to the first winding ring segment 21, ensuring the magnetic conduction effect and avoiding magnetic leakage. Since the straight magnetic strip does not require special processing, the relative production cost is lower.

[0061] The present utility model also provides an electromagnetic heating device 300, which includes the coil disk assembly 100 and an electric control device in each of the above embodiments. The specific structure of the coil disk assembly 100 refers to the above embodiments. Since this electromagnetic heating device 300 adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated here one by one.

[0062] The electromagnetic heating device 300 can be an induction cooker or an electric pressure cooker, etc. Any electromagnetic heating device 300 having the coil disk assembly 100 belongs to the electromagnetic heating device 300 described in the present utility model.

[0063] In an embodiment of the present utility model, the electromagnetic heating device 300 further includes a housing 4 for mounting the coil disc assembly 100. The housing 4 includes a panel 41, and at least a part of the panel 41 is arranged in a concave surface so as to be at least correspondingly arranged with the first winding ring segment 21. Thus, the panel 41 serves as a bearing part for the cookware 200, adapts to the concave surface of the cookware 200, and facilitates the user to well position the cookware 200 in the concave surface on the panel 41, so that the first winding ring segment 21 can be attached to the cookware 200.

[0064] Certainly, when both the first winding ring segment 21 and the second winding ring segment 22 are arranged on the installation side, the concave surface of the panel 41 is correspondingly arranged with both the first winding ring segment 21 and the second winding ring segment 22, so that the heating device 300 can adapt to larger cookware.

[0065] The above are only exemplary embodiments of the present utility model, and do not limit the patent scope of the present utility model. Any equivalent structural transformation made under the technical concept of the present utility model by using the content of the specification and drawings of the present utility model, or direct / indirect application in other related technical fields, is included in the patent protection scope of the present utility model.

Claims

1. A coil disk assembly, characterized in that: include: A bracket, the bracket having a first side and a second side opposite to each other, the first side or the second side of the bracket being set as a mounting side, the mounting side being gradually protruded from the middle to the surroundings in a direction where the first side is located; and At least two winding units are arranged on the installation side of the bracket, and the two winding units are distributed adjacent to each other along the circumference of the bracket. The winding centers of the two winding units are offset from the edge of the bracket compared to their geometric centers, so that when the two winding units are powered on, magnetic poles are formed adjacent to the edge of the bracket, and the magnetic properties of the magnetic poles of the two winding units are opposite.

2. The coil disk assembly according to claim 1, characterized in that Each of the winding units is arranged in a ring shape, and has a first winding ring segment close to the center of the bracket, and a second winding ring segment close to the edge of the bracket; In the two winding units, the directions of the currents of the two winding units are set to be opposite so that opposite magnetic poles are formed in the middle of the two winding units, and in at least one of the winding units, the width of the first winding loop segment is d1, and the width of the second winding loop segment is d2, wherein d1>d2.

3. The coil disk assembly according to claim 2, characterized in that Each of the winding units is arranged in a ring shape, and the first winding ring segment and the second winding ring segment are both located on the installation side of the bracket.

4. The coil disk assembly according to claim 1, characterized in that In the depth direction of the mounting side of the bracket, a distance d from the outer periphery of the plurality of winding units to the bottom is ≥5 mm.

5. The coil disk assembly according to claim 2, characterized in that The first side of the bracket is set as the installation side, and the first winding ring segment is set on the installation side of the bracket; The second winding loop segment is folded toward the other side of the first winding loop segment, so that the second winding loop segment is located on the second side of the bracket.

6. The coil disk assembly according to claim 2, characterized in that The coil disk assembly further includes a shielding structure disposed on a side of the winding unit facing the bracket.

7. The coil disk assembly according to claim 6, characterized in that The shielding structure includes a plurality of first magnetic strips arranged at intervals along the circumference of the bracket, each of the first magnetic strips extends outward from the middle of the bracket and is arranged in a curved shape that is compatible with the first winding ring segment.

8. The coil disk assembly according to claim 6, characterized in that The shielding structure includes a plurality of second magnetic strips arranged at intervals, and the plurality of second magnetic strips are arranged along a concave shape adapted to the first winding ring segment.

9. An electromagnetic heating device, characterized in that: Comprising the coil disk assembly according to any one of claims 1 to 8.

10. The electromagnetic heating device according to claim 9, characterized in that: The electromagnetic heating device further comprises a shell for mounting the coil disk assembly, wherein the shell comprises a panel, and the panel is at least partially arranged in a concave surface so as to be arranged corresponding to at least the first winding ring segment.

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