An antenna assembly and charging case
By designing gaps of varying lengths and strategically placing feed points within the Bluetooth earphone charging case, the problem of antenna efficiency degradation under different usage scenarios was solved. This enabled the switching of the main resonance between the closed and open states, ensuring efficient radiation performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 上海勤宽科技有限公司
- Filing Date
- 2025-08-28
- Publication Date
- 2026-07-31
AI Technical Summary
The slotted antennas of existing Bluetooth earphone charging cases suffer significant efficiency degradation in different usage scenarios, making them incompatible with multiple scenarios.
The design incorporates first and second gaps of different lengths, and feed points and power points are strategically placed on the housing to match different dielectric conditions under closed and open conditions, thereby achieving main resonance switching.
It maintains high radiation efficiency under different conditions and supports reliable implementation of Bluetooth communication and wireless search functions.
Smart Images
Figure CN224582508U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of Bluetooth headset technology, and in particular to an antenna assembly and a charging case. Background Technology
[0002] With the continuous development of the TWS earphone industry, many high-end Bluetooth earphone charging cases now feature wireless locator functionality. To achieve this, the industry commonly uses onboard, LDS (Laser-Direct-Structured), and FPC antenna solutions. However, when the casing is made entirely of metal, these solutions suffer from low radiation efficiency due to the shielding effect of the metal. Therefore, using slotted antennas is a better choice for an all-metal casing.
[0003] However, even with the slotted antenna solution, there are still performance defects in actual use. One of them is that due to the variety of usage scenarios, different states of the box can cause a serious drop in antenna efficiency, and common slotted antennas cannot be compatible with multiple scenarios.
[0004] Therefore, improvements to existing technologies are necessary.
[0005] The above information is provided as background information only to aid in understanding this disclosure and does not constitute an assertion or admission that any of the above content can be used as prior art relative to this disclosure. Utility Model Content
[0006] This invention provides an antenna assembly and a charging box to solve the problems existing in the prior art.
[0007] To achieve the above objectives, this utility model provides the following technical solution:
[0008] An antenna assembly is used in a charging case, the charging case including a housing, the housing being a metal housing;
[0009] The antenna assembly includes a first slot and a second slot formed on the housing, the first slot and the second slot having different lengths;
[0010] Feed points are provided at the ends of the first gap and the second gap, and one of the first gap and the second gap is provided with a power supply point;
[0011] in:
[0012] When the box is in the closed state, the first gap matches the medium conditions in the closed state, thereby causing the main resonance to occur in the first gap.
[0013] And / or, when the housing is in the open state, the second gap matches the medium conditions in the open state, thereby causing the main resonance to shift to the second gap.
[0014] Optionally, the box body is provided with a charging interface, and the first gap extends outward from the charging interface;
[0015] The second gap is located on the side of the charging interface away from the first gap, and there is a gap between the second gap and the charging interface.
[0016] Optionally, the length of the first gap is greater than the length of the second gap.
[0017] Optionally, the length of the first gap is λ / 4, and the length of the second gap is (λ / 4–a);
[0018] Wherein, λ is the free space wavelength corresponding to the target operating frequency, and a is a positive adjustment amount less than one-quarter of the free space wavelength.
[0019] Optionally, the first gap is provided with a power supply point, which is located in the region near the power supply point along the length direction of the first gap.
[0020] Optionally, the feed point is located at a distance of λ / 20 from the feed point along the length direction of the first gap;
[0021] Wherein, λ is the free space wavelength corresponding to the target operating frequency.
[0022] Optionally, in the closed state, the first gap serves as the main radiation path, and the second gap serves as an auxiliary path;
[0023] When the lid is open, the second slit serves as the main radiation path, and the first slit serves as the auxiliary path.
[0024] Optionally, the resonant points of the first slit and the second slit are adjacent to each other to form a broadband band in the target operating frequency band.
[0025] Optionally, a first ground plane is provided at the end of the first gap away from the first gap, a second ground plane is provided between the first gap and the second gap, and a third ground plane is provided at the end of the second gap away from the first gap.
[0026] This utility model also provides a charging box, including the antenna assembly as described in any of the preceding claims.
[0027] Compared with the prior art, the present invention has the following beneficial effects:
[0028] This utility model provides an antenna assembly and charging box. By setting the antenna assembly in a first gap and a second gap of different lengths distributed in a metal box, and reasonably arranging the feed point and power point, it can adapt to the changes in the medium caused by opening and closing the cover, realize the main resonance switching in different states, and thus obtain stronger radiation efficiency.
[0029] This invention has other features and advantages that will be apparent from or will be set forth in detail in the accompanying drawings and the following detailed description, which together serve to explain the particular principles of this invention. Attached Figure Description
[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0031] Figure 1 This is a schematic diagram of the antenna assembly's arrangement on a housing according to an embodiment of the present invention;
[0032] Figure 2 This is a schematic diagram of the structure of an antenna assembly provided in an embodiment of the present invention;
[0033] Figure 3 This is a reflection parameter S11 curve of an antenna assembly in the closed state provided by an embodiment of the present invention;
[0034] Figure 4 This is a reflection parameter S11 curve of an antenna assembly in the open state provided by an embodiment of the present invention;
[0035] Figure 5 This is a comparison diagram of the passive efficiency of an antenna assembly under different states provided in an embodiment of this utility model.
[0036] Reference numerals: 10, housing; 21, first gap; 22, second gap; 31, first ground; 32, second ground; 33, third ground; 40, charging interface. Detailed Implementation
[0037] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.
[0038] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.
[0039] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.
[0040] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.
[0041] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.
[0042] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.
[0043] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.
[0044] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0045] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0046] Please refer to Figure 1 This utility model provides an antenna assembly for use in a charging case, specifically a charging case for a Bluetooth headset. The charging case includes a box body 10, which is specifically a metal box.
[0047] In this embodiment, the antenna assembly includes a first slot 21 and a second slot 22 formed on the housing 10, and the lengths of the first slot 21 and the second slot 22 are different.
[0048] Feed points are respectively provided at the ends of the first gap 21 and the second gap 22, and one of the first gap 21 and the second gap 22 is provided with a power supply point;
[0049] in:
[0050] When the housing 10 is in the closed state, the first gap 21 matches the dielectric conditions in the closed state, thereby causing the main resonance to occur in the first gap 21.
[0051] And / or, when the housing 10 is in the open state, the second gap 22 matches the dielectric conditions in the open state, thereby causing the main resonance to shift to the second gap 22.
[0052] It is understandable that the opening and closing of the lid will cause the equivalent medium conditions of the metal casing 10 to change as follows:
[0053] When the cover is closed, the box 10 forms a relatively closed cavity with a high equivalent dielectric constant. At this time, the long first gap 21 can match the dielectric conditions, thereby stably generating the main resonance in the target operating frequency band.
[0054] When the cover is opened, the cavity is partially open, the equivalent dielectric constant decreases, and the resonance condition of the first gap 21, which was originally adapted to the closed environment, is destroyed. At this time, the shorter second gap 22 is more likely to match the new dielectric conditions, thus forming a new main resonance.
[0055] Therefore, this embodiment utilizes the change in dielectric conditions caused by the opening and closing of the cover, and switches the main resonance on the double gap to ensure that the main resonance falls on the target frequency band in different scenarios, thereby achieving compatibility with different usage scenarios and higher radiation efficiency.
[0056] Thus, the two gaps of different lengths correspond to the medium environment under closed and open conditions, respectively, realizing the switching of the master mode across states.
[0057] In one alternative embodiment, the bottom of the housing 10 is provided with a charging interface 40. A first gap 21 extends outward from the charging interface 40, utilizing the current concentration at the interface to improve excitation efficiency. A second gap 22 is arranged on the other side of the interface, maintaining a gap between it and the interface, so as to form a differentiated current path from the first gap 21.
[0058] In one alternative implementation, in order to form differentiated resonant points under different states, the length of the first gap 21 is greater than that of the second gap 22.
[0059] Preferably, the length of the first slit 21 is λ / 4, and the length of the second slit 22 is (λ / 4–a); where λ is the free space wavelength corresponding to the target operating frequency, and a is a positive adjustment amount less than one-quarter of the free space wavelength.
[0060] That is, the length of the first slit 21 is designed to be one-quarter of the free-space wavelength corresponding to the target operating frequency, and the length of the second slit 22 is one-quarter of that wavelength minus the adjustment amount 'a', where λ = c / f (c is the speed of light, f is the target frequency), and 'a' is a positive number less than λ / 4, used to make the resonant frequency of the second slit 22 slightly higher than that of the first slit 21. Through the aforementioned design, the resonant points of the two slits will not overlap, but will form an adjacent distribution. When the medium conditions change, the secondary resonant point will move to the vicinity of the main frequency and assume the role of the main mode, thereby achieving full-scene switching.
[0061] In one optional embodiment, the first slit 21 is provided with a feed point located in the region near the feed point along the length of the first slit 21. Preferably, the feed point is provided at a position λ / 20 away from its feed point along the length of the first slit 21; where λ is the free space wavelength corresponding to the target operating frequency.
[0062] Understandably, by arranging the feed point in a suitable location, optimal current distribution and impedance matching can be achieved. Specifically, the distance between the feed point and the feed location is approximately λ / 20, thereby ensuring stable main resonance under closed conditions.
[0063] In one optional implementation, in the closed state, the first slit 21 serves as the main radiation path and the second slit 22 serves as the auxiliary path; in the open state, the second slit 22 serves as the main radiation path and the first slit 21 serves as the auxiliary path.
[0064] In one alternative implementation, the resonant points of the first slot 21 and the second slot 22 are adjacent to each other to form a broadband bandwidth in the target operating frequency band. Because the resonant points of the two slots are close to each other, their responses can be combined into a wider effective bandwidth. This broadband characteristic ensures a continuous matching curve during switchover, prevents significant dips in the target frequency band, and provides stronger anti-interference capabilities.
[0065] In one optional embodiment, a first ground plane 31 is provided at the end of the first gap 21 away from the first gap 21, a second ground plane 32 is provided between the first gap 21 and the second gap 22, and a third ground plane 33 is provided at the end of the second gap 22 away from the first gap 21. The multi-ground plane structure can further stabilize the current distribution, improve the matching effect under different conditions, and reduce efficiency fluctuations.
[0066] Preferably, the gaps are filled with a non-metallic material that matches the appearance of the metal. This maintains the integrity of the metal box's appearance, preserving the industrial design, while also avoiding electromagnetic interference issues caused by exposed gaps.
[0067] To verify the effectiveness of this utility model embodiment, simulation tests were conducted on products using the antenna assembly provided in this embodiment. The simulation results are as follows: Figures 3 to 5 As shown in the simulation results, within the target operating frequency band of 2.4 GHz to 3.0 GHz, the antenna assembly of this invention maintains a stable overall efficiency curve in both the closed and open states, with the S11 parameter remaining below -10 dB, indicating good matching.
[0068] like Figure 3 As shown, in the closed state, the resonant point corresponding to the first gap 21 stably appears near the center frequency, and a secondary resonance also appears at a position higher than the main frequency; as Figure 4 As shown, in the open state, the secondary resonant point becomes the primary resonant point, capable of covering the target frequency band; as Figure 5 As shown in the efficiency comparison curves, no significant dips occurred in efficiency under either condition, and the overall efficiency level remained consistent. This fully demonstrates that this invention solves the problem of single-slot antenna failure due to changes in dielectric conditions through dual-slot switching and multi-feed grounding design.
[0069] Based on the foregoing embodiments, this utility model also provides a charging case, including the antenna assembly as described in any of the preceding embodiments. Despite its all-metal exterior, this charging case maintains high antenna radiation efficiency in various scenarios, including when the lid is closed, open, with the earphones inside, or when the case is empty, thereby supporting the reliable implementation of functions such as Bluetooth communication and wireless search.
[0070] Compared with the prior art, the present invention has the following beneficial effects:
[0071] The present invention provides an antenna assembly and charging box. By setting the antenna assembly to be distributed in the metal box 10 with different lengths in the first gap 21 and the second gap 22, and reasonably arranging the feed point and the power feed point, it can adapt to the change of medium caused by opening and closing the cover, realize the main resonance switching in different states, and thus obtain stronger radiation efficiency.
[0072] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of protection of this utility model. Any technical solutions resulting from equivalent structural or procedural substitutions or modifications made based on the essential concept of this application and utilizing the content described in the text and drawings of this application, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of protection of this utility model.
Claims
1. An antenna assembly, characterized in that, Applied to a charging case, the charging case including a box body, the box body being a metal box; The antenna assembly includes a first slot and a second slot formed on the housing, the first slot and the second slot having different lengths; Feed points are provided at the ends of the first gap and the second gap, and one of the first gap and the second gap is provided with a power supply point; in: When the box is in the closed state, the first gap matches the medium conditions in the closed state, thereby causing the main resonance to occur in the first gap. And / or, when the housing is in the open state, the second gap matches the medium conditions in the open state, thereby causing the main resonance to shift to the second gap.
2. The antenna assembly according to claim 1, characterized in that, The box is provided with a charging interface, and the first gap extends outward from the charging interface. The second gap is located on the side of the charging interface away from the first gap, and there is a gap between the second gap and the charging interface.
3. The antenna assembly according to claim 1, characterized in that, The length of the first gap is greater than the length of the second gap.
4. The antenna assembly according to claim 1, characterized in that, The length of the first slit is λ / 4, and the length of the second slit is (λ / 4–a); Wherein, λ is the free space wavelength corresponding to the target operating frequency, and a is a positive adjustment amount less than one-quarter of the free space wavelength.
5. The antenna assembly according to claim 1, characterized in that, The first gap is provided with a power supply point, which is located in the region near the power supply point along the length direction of the first gap.
6. The antenna assembly according to claim 1, characterized in that, The power supply point is located at a distance of λ / 20 from the power supply point along the length direction of the first gap. Wherein, λ is the free space wavelength corresponding to the target operating frequency.
7. The antenna assembly according to claim 1, characterized in that, When the cover is closed, the first slit serves as the main radiation path, and the second slit serves as the auxiliary path. When the lid is open, the second slit serves as the main radiation path, and the first slit serves as the auxiliary path.
8. The antenna assembly according to claim 1, characterized in that, The resonant points of the first and second slots are adjacent to each other to form a broadband band in the target operating frequency band.
9. The antenna assembly according to claim 1, characterized in that, A first ground is provided at the end of the first gap away from the first gap, a second ground is provided between the first gap and the second gap, and a third ground is provided at the end of the second gap away from the first gap.
10. A charging case, characterized in that, Includes the antenna assembly as described in any one of claims 1 to 9.