Door body assembly and cooking equipment

Abstract

The invention discloses a door body assembly which is applied to cooking equipment and comprises a door body, a choke groove is formed in the inner surface of the door body, and the choke groove is provided with a linear choke groove linear section and an arc-shaped choke groove corner section; the choke plate and the choke groove form a choke structure; the outer periphery of the choking plate is provided with a choking straight line edge corresponding to the choking groove straight line section and a choking corner edge corresponding to the choking groove corner section, the choking corner edge comprises a straight line type anti-leakage stable tangent edge, and included angles are formed between the anti-leakage stable tangent edge and the two choking straight line edges corresponding to and adjacent to the anti-leakage stable tangent edge. The invention further discloses the cooking equipment with the door body assembly. The invention has the beneficial effects that the microwave leakage rate at the four corners can be effectively reduced, and the microwave leakage rate is within an ideal range of 0.4-1.2 wm / cm < 2 >.

Description

Technical Field

[0001] The present invention relates to a door body assembly and a cooking device, belonging to the technical field of kitchen appliances. Background Art

[0002] At present, cooking devices such as steam ovens and microwave ovens have the function of microwave cooking. For the microwave function, the shielding effect of the door body is very important. If the shielding effect is not ideal, there will be a potential safety hazard of microwave leakage.

[0003] In the prior art, for the door body assembly of a cooking device, a choke groove and a choke plate are provided on its inner surface to form a choke structure, and the choke structure can shield the microwave in the inner tank of the cooking device. It is found through detection that for the vast majority of choke structures, the microwave leakage at its four sides is within the ideal range of 0.4 - 1.2 wm / cm 2 However, the microwave leakage at its four corners is as high as 2.5 - 3.3 wm / cm 2 which is much higher than the ideal range of 0.4 - 1.2 wm / cm 2 . Summary of the Invention

[0004] The purpose of the present invention is to provide a door body assembly and a cooking device, which can effectively reduce the microwave leakage at the four corners and make the microwave leakage within the ideal range of 0.4 - 1.2 wm / cm 2 .

[0005] The present invention is achieved by the following technical solutions.

[0006] A door body assembly is applied to a cooking device and includes a door body. An inner surface of the door body has a choke groove formed by being recessed along its edge. The choke groove has four choke groove straight segments, and the four choke groove straight segments are linear and any two adjacent choke groove straight segments are perpendicular to each other. An arc-shaped choke groove corner segment is connected between any two adjacent choke groove straight segments;

[0007] And a choke plate is fixed on the inner surface of the door body and is located within the part surrounded by the choke groove; there is a gap between an outer periphery of the choke plate and an outer edge of the choke groove, so that the choke plate blocks part of the choke groove and forms a choke structure with the choke groove;

[0008] The outer periphery of the choke plate has a choke straight edge corresponding to the choke groove straight segment and a choke corner edge corresponding to the choke groove corner segment. The choke corner edge includes a linear anti-leakage and stability tangent edge, and the anti-leakage and stability tangent edge has an included angle with each of the two adjacent choke straight edges.

[0009] As a further improvement of the present invention, the choke turning edge further includes a choke turning remainder edge of any line type.

[0010] As a further improvement of the present invention, one end of the anti-leakage and stability tangent edge is connected to the choke turning remainder edge, or both ends of the anti-leakage and stability tangent edge are connected to the choke turning remainder edge.

[0011] As a further improvement of the present invention, the anti-leakage and stability tangent edge extends from one end of the choke turning edge to the other end.

[0012] As a further improvement of the present invention, the angles between the anti-leakage and stability tangent edge and the two adjacent choke straight edges are of the same size.

[0013] As a further improvement of the present invention, the choke straight edge is provided with a plurality of straight edge tooth grooves arranged at intervals to form a plurality of straight edge choke teeth; and, two straight edge tooth grooves adjacent to the choke turning edge on the choke straight edge form a turning choke tooth.

[0014] As a further improvement of the present invention, the choke straight edge is provided with a plurality of straight edge tooth grooves arranged at intervals to form a plurality of straight edge choke teeth; the choke turning edge is provided with at least one turning edge tooth groove to form at least two turning choke teeth.

[0015] As a further improvement of the present invention, the turning edge tooth groove is provided as one and is located at the midline of the choke turning edge, or the turning edge tooth groove is provided as at least two and is arranged at equal intervals on the choke turning edge.

[0016] As a further improvement of the present invention, the depth of the groove body of the turning edge tooth groove is less than the depth of the groove body of the straight edge tooth groove.

[0017] A cooking device includes the door body assembly.

[0018] Advantages of the present invention:

[0019] By providing a straight-line anti-leakage and stability tangent edge on the choke turning edge, it plays a role in restoring impedance continuity to stabilize the phase, uniformize the electric field distribution, correct the reflection path, and solve the assembly accuracy problem, thereby effectively reducing the microwave leakage amount, so that the microwave leakage amount at the four corners of the door body assembly is reduced to the ideal range of 0.4 - 1.2 wm / cm 2 。 Description of the Drawings

[0020] The following will describe in detail the preferred embodiments of the present invention through the drawings to help understand the purpose and advantages of the present invention, where:

[0021] Figure 1It is a schematic structural diagram of the door body assembly;

[0022] Figure 2 It is a schematic cross-sectional view of the choke structure;

[0023] Figure 3 It is a partial schematic diagram of the door body assembly of Embodiment 1 with respect to the choke turning edge;

[0024] Figure 4 It is a partial schematic diagram of the door body assembly of Embodiment 2 with respect to the choke turning edge;

[0025] Figure 5 It is a partial schematic diagram of the door body assembly of Embodiment 3 with respect to the choke turning edge;

[0026] Figure 6 It is a partial schematic diagram of the door body assembly of Embodiment 4 with respect to the choke turning edge. Specific implementation manners

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] The orientation terms such as upper, lower, left, right, front, back, front side, back side, top, bottom, etc. mentioned or possibly mentioned in this specification are defined with respect to the structures shown in the respective drawings. The terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component. They are relative concepts and may accordingly change depending on their different positions and usage states. Therefore, these or other orientation terms should not be construed as restrictive terms.

[0029] The door body assembly of the embodiment of the present application is applied in a cooking device and opens or closes the inner cavity of the cooking device through a switch. Refer to Figures 1-6 , the door body assembly includes a door body 1, a choke plate 3, an outer door frame 11, and an outer door glass 12. Among them, the door body 1 is divided into an inner surface and an outer surface. The inner surface is the side facing the inner cavity, and the outer surface is the other side facing away from the inner cavity. The outer door frame 11 is connected to the edge of the door body 1, and the outer door glass 12 is fixed on the outer surface of the door body 1. A choke groove 2 is provided on the inner surface of the door body 1. The choke groove 2 is arranged along the edge of the door body 1 and is recessed to form a rectangular closed structure. The choke groove 2 has four choke groove straight segments 21. The four choke groove straight segments 21 are linear and any two adjacent choke groove straight segments 21 are perpendicular to each other. An arc-shaped choke groove turning segment 22 is connected between any two adjacent choke groove straight segments 21.

[0030] The choke plate 3 is fixed on the inner surface of the door body 1 and is located within the part of the inner surface surrounded by the choke groove 2. There is a gap between the outer periphery of the choke plate 3 and the outer edge of the choke groove 2, such that the choke plate 3 blocks part of the choke groove 2 and forms a choke structure with the choke groove 2.

[0031] The outer periphery of the choke plate 3 has a choke straight edge 31 that corresponds to the straight segment 21 of the choke groove and is straight, and a choke corner edge 32 that corresponds to the corner segment 22 of the choke groove. Among them, the choke corner edge 32 includes a straight anti-leakage and stability tangent edge 321, and the anti-leakage and stability tangent edge 321 has an included angle with each of the two adjacent choke straight edges 31.

[0032] In the prior art, the microwave leakage at the four corners of the door body assembly corresponding to the choke groove 2 and the choke plate 3 is relatively high, that is, the microwave leakage at the arc corners of the choke structure is relatively high. The applicant has found through research that the reasons for the high leakage include the following:

[0033] I. Impedance continuity disruption

[0034] The electromagnetic shielding effectiveness of the choke groove is based on the 1 / 4 wavelength short-circuit transmission line theory. Its core is to achieve the phase inversion cancellation of microwave energy through impedance matching. The arc edges will introduce geometric mutations at the four corners, disrupting the continuity of the cross-section of the transmission line and causing the electromagnetic field distribution in the local area to deviate from the ideal state. This geometric mutation will cause impedance mismatch, making part of the microwave energy unable to be effectively cancelled through phase inversion and thus leaking from the door body gap.

[0035] II. Electromagnetic field edge effect

[0036] The electric field distribution of microwaves at the edges of metal structures follows the edge effect law. The smaller the radius of curvature, the more significant the field strength concentration phenomenon. Although the curvature characteristics of the arc edges at the four corners are better than those of acute angles, electric field convergence points will still be formed locally. This field strength concentration may cause two problems: one is that the local electric field strength exceeds the voltage withstand threshold of the door body material, forming microdischarge or breakdown channels; the other is that the uneven field strength distribution causes part of the energy to bypass the shielding path of the choke groove and directly leak from the high field strength area.

[0037] III. Reflection path problem

[0038] The reflection path accuracy of microwaves in the door body choke structure directly determines the leakage suppression effect. The geometric characteristics of the arc edges at the four corners will cause microwaves to scatter and diffract: on the one hand, the incident wave undergoes non-directional reflection on the arc surface, and part of the energy deviates from the preset path; on the other hand, the curvature of the arc edge will cause a diffraction effect, generating diffracted waves that bypass the choke groove. Both of these phenomena will weaken the cancellation effect of phase inversion and form residual leakage.

[0039] IV. Processing and assembly accuracy problem

[0040] The assembly accuracy of the door body choke structure directly affects the shielding performance. The requirements for the arc edge in mold processing and stamping processes are extremely high. First, the curvature radius of the arc angle needs to be strictly matched with the choke groove. If there is a deviation of more than ±0.1 mm, local gaps will occur between the choke plate and the groove body. Second, there is a springback effect after the metal sheet is stamped. The springback compensation of the arc angle needs to be achieved through complex mold design, and it is difficult to ensure process stability.

[0041] In this embodiment, by setting a straight anti-leakage and stability tangent edge 321 on the choke turning edge 32, the arc angle structure of the choke structure is damaged and changed, thereby reducing the microwave leakage. Specifically, it is elaborated in detail from the following aspects:

[0042] I. Impedance continuity optimization

[0043] By introducing a straight anti-leakage and stability tangent edge 321 on the choke turning edge 32, the straight boundary conditions at the four corners are restored, making the propagation path of the electromagnetic wave consistent with the theoretical design. The uniform cross-sectional characteristics maintain the impedance continuity, ensuring that the microwave undergoes a complete 1 / 4 wavelength path in the choke groove 2 and forms a stable 180° phase inversion, that is, the cancellation effect can be maximized by the stable phase method. In addition, the straight anti-leakage and stability tangent edge 321 suppresses the excitation of high-order electromagnetic modes, avoiding impedance fluctuations caused by multimode coupling and further improving the shielding efficiency.

[0044] II. Mitigation of electric field concentration

[0045] The straight anti-leakage and stability tangent edge 321 eliminates the sudden change in curvature at the four corners, making the electric field show a uniform gradient distribution along the edge. The homogenized field strength characteristics reduce the local energy density and avoid the risk of dielectric breakdown caused by field strength concentration. At the same time, the straight edge design reduces the distortion of the electric field lines at the four corners, ensuring that the electric field energy is restricted within the designed reflection path of the choke groove 2, rather than escaping through edge diffraction.

[0046] III. Reflection path correction

[0047] The straight anti-leakage and stability tangent edge 321 constrains the reflection behavior of the microwave to the specular reflection mode by providing a flat reflection interface. This design ensures the certainty of the propagation path of the reflected wave, making the reflected wave and the original leakage wave strictly out-of-phase superimposed in space. At the same time, the straight anti-leakage and stability tangent edge 321 suppresses the generation of diffracted waves, reducing the possibility of energy leakage through the diffraction path. By optimizing the consistency of the reflection path, the straight edge structure controls the reflection phase error well, thus significantly improving the energy cancellation efficiency.

[0048] IV. Solving the assembly accuracy problem

[0049] The straight anti-leakage and stability tangent edge 321 edge type setting reduces the processing complexity compared with the arc edge. The manufacturing tolerance of the straight stamping die can be controlled within ±0.02 mm, and the springback direction is single. The springback error can be eliminated through pre-compensation design. This process characteristic greatly improves the uniformity of the assembly gap between the choke plate 3 and the choke groove 2, effectively avoiding leakage caused by excessive local gaps.

[0050] In addition, it should be noted that:

[0051] Theoretically, setting the corner section 22 of the choke groove as a straight structure instead of an arc structure can also achieve the above technical effects. Or, the technical effect of the straight corner section 22 of the choke groove combined with the straight anti-leakage and stability tangent edge 321 is better.

[0052] However, in actual production and processing, the choke groove 2 is formed on the door body 1 through a stamping process. If the corner section 22 of the choke groove is designed as a straight structure, a more complex stamping process is required, which involves the complexity of the die, related material handling problems, and the addition of heat treatment processes, resulting in higher processing difficulty and increased production and processing costs. In addition, designing the corner section 22 of the choke groove as a straight structure will cause the stress at the corresponding corner section 22 of the door body 1 to be relatively concentrated, which is not conducive to the structural strength stability.

[0053] On the contrary, compared with the arc-shaped processing, setting the choke corner edge 32 to include the straight anti-leakage and stability tangent edge 321 has relatively lower processing difficulty. Therefore, it can not only effectively reduce the microwave leakage amount, but also reduce the processing difficulty of the choke plate 3.

[0054] Implementation Case 1:

[0055] A door body assembly, referring to Figure 3 , in this implementation case, the choke corner edge 32 includes an anti-leakage and stability tangent edge 321 and a choke corner remaining edge 322. Among them, the anti-leakage and stability tangent edge 321 is straight, and the choke corner remaining edge 322 can be any line type, such as straight, arc, curve, etc.

[0056] In one implementation, both sides of the anti-leakage and stability tangent edge 321 are connected to the choke corner remaining edge 322, that is, as Figure 3 shown, in one implementation, one end of the anti-leakage and stability tangent edge 321 is connected to the choke corner remaining edge 322.

[0057] In this implementation case, the included angles between the anti-leakage and stability tangent edge 321 and the two adjacent choke straight edges 31 are the same. That is, when the choke straight edges 31 are vertical and horizontal, the anti-leakage and stability tangent edge 321 is inclined at 45°.

[0058] In this embodiment, the anti-leakage and stability tangent edge 321 plays a role in restoring impedance continuity to stabilize the phase, uniformize the electric field distribution, and correct the reflection path, thereby reducing the microwave leakage. The choke corner remaining edge 322 is a decorative edge outside the anti-leakage and stability tangent edge 321, making the choke corner edge 32 complete in shape.

[0059] Embodiment 2:

[0060] A door body assembly. Refer to Figure 4 , in this embodiment, the choke corner edge 32 is only provided with a linear anti-leakage and stability tangent edge 321, that is, the anti-leakage and stability tangent edge 321 extends from one end of the choke corner edge 32 to the other end, and both ends of the anti-leakage and stability tangent edge 321 are respectively connected to two adjacent choke straight edges 31.

[0061] In this embodiment, the angles between the anti-leakage and stability tangent edge 321 and the two adjacent choke straight edges 31 are the same. That is, when the choke straight edges 31 are vertical and horizontal, the anti-leakage and stability tangent edge 321 is inclined at 45°.

[0062] Embodiment 3:

[0063] A door body assembly. Refer to Figure 5 , based on Embodiment 2, in this embodiment, the choke straight edge 31 has a plurality of linearly spaced straight edge grooves 31a to form a plurality of straight edge choke teeth 31b. The choke corner edge 32 is not provided with grooves. Therefore, the two straight edge grooves 31a adjacent to the choke corner edge 32 on the choke straight edge 31 form a corner choke tooth 32b.

[0064] The straight edge choke teeth 31b extend the microwave propagation path through a periodic groove structure, generate multiple reflected wave superpositions using the 1 / 4 wavelength resonance principle, form impedance mutation points on the straight edge to reflect the leaked energy, and the electric field gradient distribution between adjacent grooves can suppress the propagation of transverse surface waves.

[0065] In this embodiment, since the choke corner edge 32 is not provided with grooves, the adjacent straight segment grooves naturally extend and intersect to form a corner choke tooth 32b that is wider than the straight edge choke tooth 31b. The corner choke tooth 32b destroys the phase consistency of the microwave diffraction path, forcing the diffracted waves with different incident angles to generate self-interference cancellation in the corner area.

[0066] Embodiment 4:

[0067] A door body assembly. Refer to Figure 6, Based on Implementation Case 2, in this implementation case, the choke straight edge 31 has a plurality of straight edge teeth grooves 31a arranged at intervals to form a plurality of straight edge choke teeth 31b. The choke corner edge 32 has at least one corner edge teeth groove 32a to form at least two corner choke teeth 32b.

[0068] The difference between this implementation case and Implementation Case 3 is that the corner choke teeth 32b are not provided on the choke corner edge 32 in Implementation Case 3, while in this implementation case, the corner edge teeth groove 32a is provided on the corner choke teeth 32b.

[0069] In this implementation case, by providing the corner edge teeth groove 32a on the choke corner edge 32 to form the corner choke teeth 32b, the single diffraction path is divided into multiple resonant cavities through periodic impedance mutation, forcing the microwave to experience multiple phase inversions, triggering self-interference cancellation of the diffracted wave. At the same time, the corner edge teeth groove 32a destroys the continuity of the surface wave propagation, reduces microwave leakage and suppresses the extension of the frequency band to the high frequency.

[0070] In some implementation manners, the corner edge teeth groove 32a is provided as one and is located at the midline of the choke corner edge 32.

[0071] In another implementation manner, the corner edge teeth groove 32a is provided as at least two and is arranged at equal intervals on the choke corner edge 32.

[0072] In this implementation case, the groove depth of the corner edge teeth groove 32a is less than the groove depth of the straight edge teeth groove 31a. More specifically, the groove body of the corner edge teeth groove 32a is 30%-70% of the groove body of the straight edge teeth groove 31a. It should be noted that the groove depth refers to the length from the groove opening to the groove bottom, that is, referring to Figure 6 , the length of d2 is less than d1.

[0073] Implementation Case 5:

[0074] A cooking device includes a door body assembly, and the door body assembly is as shown in Implementation Cases 1-4. Among them, the cooking device includes a steam oven and a microwave oven.

[0075] Experimental Case:

[0076] The gaps between the four straight edges of the door body assembly and the inner container of the cooking device are pasted with aluminum foil, and only the gaps between the four corner edges of the door body assembly and the inner container are left. The four corner edges of the door body assembly are respectively marked as the 1st position, the 2nd position, the 3rd position, and the 4th position, which respectively correspond to the arc corners of the choke structure. Then, the microwave leakage amounts at the 1st position, the 2nd position, the 3rd position, and the 4th position are detected. Since the gaps at the straight edges are sealed with aluminum foil, the microwave leakage at the straight edges can be effectively avoided from interfering with the four corner edges, so as to ensure the effectiveness of the detection.

[0077] The implementation cases 3 and 4 were respectively detected, and the detection results are as follows:

[0078] The microwave leakage detection result of implementation case 3:

[0079] The first group of data

[0080]

[0081] The second group of data

[0082]

[0083] The third group of data

[0084]

[0085] It can be seen that the microwave leakage of implementation case 3 decreased from the range of 2.5 - 3.3 wm / cm 2 to the range of 0.4 - 1.2 wm / cm 2 .

[0086] The microwave leakage detection result of implementation case 4:

[0087] The first group of data

[0088]

[0089] The second group of data

[0090]

[0091] The third group of data

[0092]

[0093] It can be seen that the microwave leakage of implementation case 4 decreased from the range of 2.5 - 3.3 wm / cm 2 to the range of 0.4 - 1.2 wm / cm 2 .

[0094] It should be noted that the leakage at positions 3 and 4 is generally higher than that at positions 1 and 2. After research, the applicant found that the reasons for this result are as follows:

[0095] Since the experimental materials are not the final commercial products, the requirements for manufacturing and processing are lower than those for commercialization. Due to varying degrees of depressions and protrusions in the door body assembly, the flatness is not ideal. Moreover, there are differences in the hinge force magnitude and installation force deviation during assembly, ultimately resulting in different gaps between the door body assembly and the front panel of the inner container. Additionally, the projection lengths of the top edge and bottom edge of the door body assembly on the front panel of the inner container are inconsistent. Generally, the projection length of the top edge of the door body assembly on the front panel of the inner container is greater than that of the bottom edge of the door body assembly on the front panel of the inner container. Therefore, the microwave leakage at points 1 and 2 is less than that at points 3 and 4, which is not a defect of the technical solution.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A door assembly, applied to cooking equipment, characterized in that: The invention comprises a door body (1), wherein the inner surface of the door body (1) has a choke slot (2) arranged along the edge thereof and formed in a concave shape, wherein the choke slot (2) has four choke slot straight line segments (21), wherein the four choke slot straight line segments (21) are straight line-shaped and any two adjacent choke slot straight line segments (21) are perpendicular to each other, and any two adjacent choke slot straight line segments (21) are connected by an arc-shaped choke slot corner segment (22); and a choke plate (3), the choke plate (3) being fixed on the inner surface of the door body (1) and being located within the portion enclosed by the choke slot (2); a gap being provided between the outer periphery of the choke plate (3) and the outer edge of the choke slot (2), so that the choke plate (3) blocks a portion of the choke slot (2) and forms a choke structure with the choke slot (2); The outer periphery of the choke plate (3) comprises a straight choke straight edge (31) corresponding to the straight section (21) of the choke slot, and a choke corner edge (32) corresponding to the corner section (22) of the choke slot, wherein the choke corner edge (32) comprises a straight anti-leakage steady-phase tangent edge (321), and the anti-leakage steady-phase tangent edge (321) and two adjacent choke straight edges (31) have an included angle.

2. The door assembly according to claim 1, characterized in that: The choke corner edge (32) further includes a choke corner residual edge (322) of any linear type.

3. The door assembly according to claim 2, characterized in that: One end of the anti-leakage stable phase tangent edge (321) is connected to the choke corner residual edge (322), or both ends of the anti-leakage stable phase tangent edge (321) are connected to the choke corner residual edge (322).

4. The door assembly according to claim 1, characterized in that: The anti-leakage stabilizing phase tangent edge (321) extends from one end of the choke corner edge (32) to the other end thereof.

5. The door assembly according to any one of claims 1 to 4, characterized in that: The included angles of the anti-leakage stabilizing phase tangent edge (321) and two adjacent choke straight line edges (31) are the same.

6. The door assembly according to any one of claims 1 to 4, characterized in that: The choke straight edge (31) has a plurality of straight edge tooth grooves (31a) arranged at intervals from each other to form a plurality of straight edge choke teeth (31b); and two straight edge tooth grooves (31a) adjacent to the choke straight edge (31) and the choke corner edge (32) form corner choke teeth (32b).

7. The door assembly according to any one of claims 1 to 4, characterized in that: The choke straight edge (31) has a plurality of straight edge tooth grooves (31a) arranged at intervals from each other to form a plurality of straight edge choke teeth (31b); the choke corner edge (32) has at least one corner edge tooth groove (32a) to form at least two corner choke teeth (32b).

8. The door assembly according to claim 7, characterized in that: The corner edge tooth groove (32a) is provided as one and is located at the midline of the choke corner edge (32); or, the corner edge tooth groove (32a) is provided as at least two and is arranged at equal intervals on the choke corner edge (32).

9. The door assembly according to claim 7, characterized in that: The groove body depth of the corner side tooth groove (32a) is smaller than the groove body depth of the straight side tooth groove (31a).

10. A cooking device, characterized in that: The invention comprises the door assembly as described in any one of claims 1 to 9.

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