Onboard antenna and detachable RF module applied to smoke sensing

Abstract

The utility model provides an onboard antenna and a detachable RF module applied to smoke sensing, and relates to the technical field of antennae, the onboard antenna comprises a module mainboard, the antenna is arranged on the module mainboard, and the antenna is formed by a circuit etched on the module mainboard. The antenna comprises an antenna main body, and the antenna main body is connected with a feeder branch, a short-circuit branch and an antenna tail end. The antenna short-circuit branch is led out from the reference ground of the module mainboard, and the tail ends of the antenna short-circuit branch and the antenna feed circuit branch intersect at the edge of the module mainboard structure to form an IFA antenna which is equivalent to a parallel inductor so as to adjust the inductive reactance of the antenna; the antenna main body is a section of S-shaped wire led out from the tail end of the antenna feed circuit branch knot, and the antenna main body is bent and coiled every winding width; and the antenna feed circuit branch knot is led out by the radio frequency module and is wired to the board edge clearance area of the module mainboard. According to the utility model, the small-size PCB is designed, and the small-size onboard antenna is arranged on the small-size PCB, so that the purpose of wireless expansion can be realized by only needing a very small size.

Description

Technical Field

[0001] The utility model relates to the technical field of antennas, in particular to a board-mounted antenna and a detachable RF module applied to a smoke detector. Background Art

[0002] For traditional independent smoke detectors, during the structural design stage, the design plan for expanding wireless components was not considered. Therefore, when expanding wireless functions, there are often situations of insufficient structural space and difficult access.

[0003] Currently, most antennas applied to smoke detectors in the market are spring or wire antennas. Although their performance is better, they have disadvantages such as inconvenient installation, large space occupation, affecting aesthetics, and being easily damaged. Therefore, designing a board-mounted antenna that can ensure performance and is easy to install, as well as a detachable RF module applied to a smoke detector, has important practical value. Summary of the Utility Model

[0004] The utility model provides a board-mounted antenna and a detachable RF module applied to a smoke detector to solve the above-mentioned problems: Currently, most antennas applied to smoke detectors in the market are spring or wire antennas. Although their performance is better, they have disadvantages such as inconvenient installation, large space occupation, affecting aesthetics, and being easily damaged.

[0005] To solve the above technical problems, the utility model discloses a board-mounted antenna, including: a module main board, with the antenna disposed on the module main board, and the antenna is formed by a circuit etched on the module main board.

[0006] Preferably, the antenna includes:

[0007] An antenna body, which is connected to a feed line stub, a short-circuit stub, and an antenna end.

[0008] Preferably, the antenna short-circuit stub is led out from the reference ground of the module main board. The antenna short-circuit stub intersects with the end of the antenna feed line stub at the edge of the module main board structure, forming an IFA antenna, which acts as a parallel inductor to adjust the antenna inductive reactance;

[0009] The antenna body is a section of S-shaped trace led out from the end of the antenna feed line stub, and is bent and coiled every winding width;

[0010] The antenna feed line stub is led out from the RF module and runs towards the clearance area at the edge of the module main board.

[0011] Preferably, the antenna end ends at a 90-degree angle to the edge of the module main board with the end of the antenna body. The direction of the antenna end is opposite to the reference ground, and the antenna end is far from the reference ground, increasing the antenna area and occupying more clearance.

[0012] Preferably, the width of the antenna shorting stub is 0.8 mm and the length is 8.92 mm;

[0013] The width of the antenna feed stub is 0.8 mm and the length is 9.15 mm;

[0014] The winding width of the antenna body is 1.6 mm or mmm; the first winding length of the antenna body is 6 mm, the second, fourth, fifth, and sixth winding lengths of the antenna body are 11 mm, the third winding length (2.5) of the antenna body is 9.5 mm, and the total length of the antenna body is 138.2 mm;

[0015] The width of the antenna end is 0.8 mm and the length is 4.3 mm.

[0016] Preferably, the antenna body adjusts the routing shape and length according to the actual space and the required frequency band, and clearance treatment is performed around it. By adjusting the winding width and winding length of the antenna body, the required frequency band and capacitive reactance of the antenna are adjusted, the return loss is optimized, and the bandwidth is increased.

[0017] Preferably, the antenna is made by directly etching FR4 copper foil on the module main board.

[0018] The present utility model also discloses a detachable RF module applied to a smoke detector, including the on-board antenna. The detachable RF module 1 applied to a smoke detector further includes:

[0019] A radio frequency module, arranged on the module main board, the radio frequency module communicates with the outside through the antenna, and the module main board is detachably connected to the smoke detector;

[0020] Interface pins, an interface is designed inside the smoke detector, and the interface pins are connected to the interface.

[0021] Preferably, the radio frequency module includes a radio frequency transceiver circuit, including a transmitting module and a receiving module. A power management system is arranged inside the smoke detector, and the feed stub is connected to the radio frequency module.

[0022] Preferably, the module main board is detachably connected to the smoke detector through a connection structure. The smoke detector includes a housing, and the connection structure includes:

[0023] Two groups of left-right symmetric limiting components. The left limiting component includes:

[0024] A first fixing block, fixedly connected to the left inner wall of the housing, and a chute is arranged at the upper right part of the first fixing block;

[0025] A limiting block, an extension part is integrally arranged at the lower right part of the limiting block, the extension part is slidably connected in the chute along the left-right direction, a first spring is arranged between the extension part and the inner wall of the chute, and a first inclined surface with a higher left and a lower right is arranged on the left side of the limiting block; the right side of the upper part of the limiting block located at the extension part is a clamping surface;

[0026] The vertical screw is threadedly connected to the first fixing block and penetrates through the first fixing block. A spherical surface is provided at the upper end of the vertical screw, and the spherical surface is in contact with the inclined surface part 1.

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

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] Convenient installation: The board-mounted antenna is directly arranged on the module main board without additional installation steps. At the same time, the RF module is designed with a detachable structure, which is convenient for users to replace or repair. Good aesthetics: The antenna adopts a flattened design and is integrated inside the smoke detector without affecting the appearance aesthetics. High stability: The antenna is made of FR4 copper foil etching, with low cost and can ensure stable signal transmission; the RF module internally integrates a radio frequency transceiver circuit to realize the wireless data transmission function. Easy to upgrade: The RF module is designed with a detachable structure, allowing users to easily disassemble and replace with a new module when replacement or upgrade is needed. Description of the Drawings

[0030] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0031] Figure 1 is a schematic structural diagram of a detachable RF module applied to a smoke detector according to an embodiment of the present invention Figure 1 ;

[0032] Figure 2 is a schematic structural diagram of the antenna according to an embodiment of the present invention;

[0033] Figure 3 is a schematic structural diagram of a detachable RF module applied to a smoke detector according to an embodiment of the present invention Figure 2 ;

[0034] Figure 4 is a schematic structural diagram of an embodiment of the connection structure of the present invention;

[0035] Figure 5 is Figure 4 a schematic enlarged view of the structure at A in

[0036] In the figure: 1. RF module; 1.1 RF module group; 1.2 carrier board antenna; 1.3 interface pin; 1.4 module main board; 2.1 feeder stub; 2.2 short - circuit stub; 2.3 antenna body; 2.4 winding width; 2.5 winding length; 2.6 antenna end; 3. housing; 4. limiting component; 41 fixing block; 42 chute; 43 limiting block; 431 extension part; 432 first inclined surface; 433 clamping surface; 434 second inclined surface; 44 vertical screw; 45 spherical surface; 46 first spring; 5. auxiliary component; 51 mounting shell; 52 connecting plate; 53 vertical rod; 54 pressing block; 55 third inclined surface; 56 connecting block; 57 horizontal rod. Detailed implementation manners

[0037] The preferred embodiments of the present utility model will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustration and explanation of the present utility model, and are not used to limit the present utility model.

[0038] In addition, in the present utility model, descriptions such as "first" and "second" are only for descriptive purposes, and do not specifically refer to the order or sequence. Nor are they used to limit the present utility model. They are merely used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions and technical features between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement them. 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.

[0039] The present utility model provides the following embodiments

[0040] Embodiment 1. The embodiment of the present utility model provides a board - mounted antenna, including: a module main board 1.4, and the antenna is arranged on the module main board 1.4 and is formed by a circuit etched on the module main board 1.4.

[0041] Preferably, the antenna includes:

[0042] An antenna body 2.3, and the antenna body 2.3 is connected to a feeder stub 2.1, a short - circuit stub 2.2, and an antenna end 2.6. All parts of the antenna are integrally formed by PCB traces;

[0043] Preferably, the antenna shorting stub 2.2 is led out from the reference ground of the module main board 1.4. The end of the antenna feeding stub 2.1 intersects with the end of the antenna shorting stub 2.2 at the edge of the structure of the module main board 1.4, forming an IFA antenna, which functions as a parallel inductor to adjust the antenna inductive reactance. The intersection position of the antenna shorting stub 2.2 and the antenna feeding stub 2.1 and the position led out from the reference ground can be adjusted according to parameters such as the size and shape of the PCB, the SMITH chart, and S11 to optimize the antenna performance.

[0044] The antenna body 2.3 is a section of S-shaped trace led out from the end of the antenna feeding stub 2.1, and is bent and coiled every winding width 2.4. The shape and length of the trace of the antenna body 2.3 are adjusted according to the actual space and the required frequency band, and clearance is made around it. By adjusting the winding width 2.4 and the winding length 2.5, the required frequency band and capacitive reactance of the antenna are adjusted, the return loss is optimized, and the bandwidth is increased.

[0045] The antenna feeding stub 2.1 is led out from the RF module and routes to the clearance area at the edge of the module main board 1.4. The routing direction and length determine the overall layout and shape of the antenna, and can be adjusted according to the actual size of the PCB board and the environmental clearance. In the embodiment of the present invention, it routes in the opposite direction to the reference ground and reaches the edge of the board structure to obtain greater clearance and better antenna radiation directivity.

[0046] Preferably, the end 2.6 of the antenna ends at a 90-degree angle to the end of the antenna body 2.3 at the edge of the module main board 1.4. The direction of the end 2.6 of the antenna is approximately in the opposite direction of the reference ground. The end 2.6 of the antenna is far from the reference ground, increasing the antenna area and occupying more clearance to improve the radiation directivity and radiation efficiency.

[0047] Preferably, the line width of the antenna shorting stub 2.2 is 0.8 mm and the line length is 8.92 mm;

[0048] The line width of the antenna feeding stub 2.1 is 0.8 mm and the line length is 9.15 mm;

[0049] The winding width 2.4 of the antenna body 2.3 is 1.6 mm or 2.4 mm. The first winding length 2.5 of the antenna body 2.3 is 6 mm, the second, fourth, fifth, and sixth winding lengths 2.5 of the antenna body 2.3 are 11 mm, the third winding length 2.5 of the antenna body 2.3 is 9.5 mm, and the total length of the antenna body 2.3 is 138.2 mm; the line width is 0.8 mm;

[0050] The line width of the end 2.6 of the antenna is 0.8 mm and the line length is 4.3 mm.

[0051] Preferably, the antenna body 2.3 adjusts the routing shape and length according to the actual space and the required frequency band, and clearance treatment is performed around it. By adjusting the winding width 2.4 and winding length 2.5 of the antenna body 2.3, the required frequency band and capacitive reactance of the antenna are adjusted, the return loss is optimized, and the bandwidth is increased.

[0052] Preferably, the antenna is made by directly etching FR4 copper foil on the module main board 1.4 to ensure stable signal transmission.

[0053] The present utility model also discloses a detachable RF module applied to a smoke detector, which is characterized in that it includes the on-board antenna 1.2 described above. The detachable RF module 1 applied to a smoke detector further includes:

[0054] A radio frequency module 1.1, which is arranged on the module main board 1.4. The radio frequency module 1.1 communicates with the outside through the antenna, and the module main board 1.4 is detachably connected to the smoke detector (the RF module has a detachable structure. The RF module is designed with a detachable structure, allowing users to easily disassemble and replace with a new module when replacement or upgrade is needed);

[0055] Interface pins 1.3. An interface is designed inside the smoke detector, and the interface pins 1.3 are connected to the interface.

[0056] In one embodiment, the detachable structure may include the following structures: a slot designed inside the smoke detector, a clamping groove is correspondingly arranged in the slot, a clamping block is arranged on the module main board 1.4, and the clamping block is detachably connected to the clamping groove; the detachable structure can also be a screw. Screw holes are arranged at the installation position of the module main board 1.4 inside the smoke detector, and the module main board and the smoke detector are connected using screws;

[0057] Preferably, the radio frequency module 1.1 includes a radio frequency transceiver circuit, including a transmitting module and a receiving module. A power management system is arranged inside the smoke detector, and the feeder stub 2.1 is connected to the radio frequency module 1.1. The RF module includes a radio frequency transceiver circuit to realize the function of wireless data communication. It communicates with the outside through the on-board antenna 1.1. The RF module is designed with an interface matching the communication with the smoke detector, facilitating users to install it inside the smoke detector. The smoke detector communicates and networks with other external smoke detector devices through the RF module to realize data transmission and monitoring. A power management system is also designed inside the smoke detector to provide stable power supply for the RF module.

[0058] The present utility model designs a small-sized PCB (module main board) with a small-sized on-board antenna on it to solve this pain point requirement, and the goal of expanding wireless can be achieved with only a very small size.

[0059] The working principle and beneficial effects of the above technical solution are as follows:

[0060] Easy to install: The on-board antenna 1.1 is directly arranged on the module main board 1.4 without additional installation steps. At the same time, the RF module is designed with a detachable structure, which is convenient for users to replace or repair. Good aesthetics: The antenna adopts a flattened design and is integrated inside the smoke detector without affecting the appearance. High stability: The antenna is made of FR4 copper foil etching, with low cost and can ensure stable signal transmission; the RF module internally integrates a radio frequency transceiver circuit to achieve the function of wireless data transmission. Easy to upgrade: The RF module is designed with a detachable structure, allowing users to easily disassemble and replace with a new module when replacement or upgrade is needed.

[0061] Embodiment 2, based on Embodiment 1, as Figure 4 、 Figure 5 shown, the module main board 1.4 is detachably connected to the smoke detector through a connection structure. The smoke detector includes a housing 3, and the connection structure includes:

[0062] Two groups of left-right symmetric limiting components 4. The left limiting component 4 includes:

[0063] A first fixing block 41 fixedly connected to the left inner wall of the housing 3. A chute 42 is provided at the upper right part of the first fixing block 41;

[0064] A limiting block 43. An extension part 431 is integrally provided at the lower right part of the limiting block 43. The extension part 431 is slidably connected in the chute 42 along the left-right direction. A first spring 46 is provided between the extension part 431 and the inner wall of the chute 42. A first inclined surface 432 with a higher left and lower right is provided on the left side of the limiting block 43; the right side of the upper part of the limiting block 43 where the extension part 431 is located is a clamping surface 433;

[0065] A vertical screw 44 is threadedly connected to the first fixing block 41 and passes through the first fixing block 41. A spherical surface 45 is provided at the upper end of the vertical screw 44, and the spherical surface 45 contacts the first inclined surface 432.

[0066] The smoke detector (smoke sensor) including the housing 3 is prior art, and other structures of the smoke detector (smoke sensor) are also prior art, such as 221125334U, CN209118457U, CN308662977S, CN202223003902.X, CN202320080288.2.

[0067] In the present utility model, two groups of front-back symmetric limiting components can also be provided, and a total of four groups of limiting components can be provided, which are arranged along the front, back, left, and right sides of the module main board 1.4.

[0068] Among them, an elastic pad can be provided on the clamping surface 433 to avoid damaging the module main board 1.4.

[0069] The beneficial effects of the above technical solutions are:

[0070] In the present utility model, as Figure 4 shown, when installing the module main board 1.4, place the module main board 1.4 at the position as Figure 4 shown (the left and right lower parts of the module main board 1.4 are respectively placed on the extension parts 431 on the left and right), and then rotate the vertical screws 44 on both the left and right sides, so that the vertical screws 44 drive the spherical surface 45 to move upward. The spherical surface 45 is in contact and cooperation with the inclined surface part one 432, so that the limiting blocks 43 on both the left and right sides approach each other. Finally, the clamping surface 433 clamps both sides of the module main board 1.4, and the left and right lower parts of the module main board 1.4 are respectively supported on the corresponding extension parts 431, realizing anti-falling and ensuring the installation stability of the module main board 1.4.

[0071] Embodiment 3, on the basis of Embodiment 2, as Figure 4 、 Figure 5 shown,

[0072] On the upper right side of the left limiting block 43, there is also provided an inclined surface part two 434 with a lower left and higher right (on the right side, there is a corresponding structure symmetric to the inclined surface part two 434 on the left side); the connecting structure further includes: two groups of left-right symmetric auxiliary components 5, and the two groups of auxiliary components 5 respectively correspond to the two groups of limiting components 4. The left auxiliary component 5 includes:

[0073] An installation shell 51, fixedly connected to the inner wall of the upper end of the shell 3. The upper end inside the installation shell 51 is slidably connected with a connecting plate 52. A second spring is arranged between the connecting plate 52 and the inner wall of the installation shell 51. The lower end of the connecting plate 52 is fixedly connected with a vertical rod 53. The vertical rod 53 slides through the installation shell 51 along the up and down direction. The lower end of the vertical rod 53 is provided with a pressing block 54. The left side of the vertical rod 53 is integrally extended with a horizontal rod 57. The left side of the horizontal rod 57 is provided with an inclined surface part three 55. The inclined surface part three 55 is in fitting contact with the inclined surface part two 434 (the inclined surface part three 55 and the inclined surface part two 434 have the same angle); an elastic pad can be arranged at the lower end of the pressing block 54 to avoid damaging the module main board 1.4;

[0074] A connecting block 56, with its left and right ends connected between the pressing blocks 54 on both the left and right sides (wherein it can also be the following structure: on the mutually approaching sides of the two pressing blocks 54, chutes can be provided. The middle parts of the left and right sides of the connecting block 56 are provided with connecting sliders. The connecting sliders slide along the front and back direction in the corresponding chutes. The connecting block 56 and the chutes are correspondingly provided with screw holes, and the connecting block 56 can be fixed to the pressing block 54 through screws; due to the cooperation of the above-mentioned connecting sliders and chutes, the connecting block 56 can adjust the position of pressing the module main board 1.4 in the front and back direction as needed to adapt to module main boards 1.4 of different sizes), and elastic pads for pressing on the back of the module main board 1.4 can be arranged at the lower ends of the connecting block 56 and the pressing block 54.

[0075] Optionally, a heat dissipation device (such as a semiconductor refrigeration chip) can be provided on the connection block 56 for dissipating heat from the module main board 1.4;

[0076] The working principle and beneficial effects of the above technical solution are as follows:

[0077] On the basis of the above Embodiment 3, when the limit blocks 43 on the left and right sides are made to approach each other, the inclined surface three 55 is in fitting contact with the inclined surface two 434, so that the two horizontal rods 57 on the left and right move downward, and the pressing block 54 and the connection block 56 press the module main board 1.4 tightly on the extension part 431, realizing the up-and-down direction limit of the module main board 1.4. Combined with the above lateral limit, the installation stability of the module main board 1.4 is ensured.

[0078] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A board-mounted antenna, characterized in that: include: A module mainboard (1.4), the antenna being arranged on the module mainboard (1.4), the antenna being formed by a circuit etched on the module mainboard (1.4); The antenna comprises: The antenna body (2.3) is connected to the feeder branch (2.1), the short-circuit branch (2.2), and the antenna end (2.6); The antenna short-circuit branch (2.2) is led out from the reference ground of the module mainboard (1.4), and the ends of the antenna short-circuit branch (2.2) and the antenna feed branch (2.1) intersect at the edge of the module mainboard (1.4) structure to form an IFA antenna, which plays a role equivalent to a parallel inductor to adjust the antenna inductive reactance; The antenna body (2.3) is a section of S-shaped wiring drawn from the end of the antenna feed branch (2.1), and is bent and coiled every time the winding width (2.4) is passed; The antenna feed branch (2.1) is led out from the radio frequency module and routed to a clearance area at the edge of the module main board (1.4).

2. The onboard antenna according to claim 1, characterized in that: The antenna end (2.6) and the end of the antenna body (2.3) are 90 degrees apart and end at the edge of the module mainboard (1.4). The direction of the antenna end (2.6) is opposite to the reference ground. The antenna end (2.6) is far from the reference ground, thereby increasing the antenna area and occupying more clearance.

3. The onboard antenna according to claim 1, characterized in that: The antenna short-circuit branch (2.2) has a line width of 0.8 mm and a line length of 8.92 mm; The antenna feed branch (2.1) has a line width of 0.8 mm and a line length of 9.15 mm; The winding width (2.4) of the antenna body (2.3) is 1.6 mm or 2.4 mm; the first winding length (2.5) of the antenna body (2.3) is 6 mm, the second, fourth, fifth and sixth winding lengths (2.5) of the antenna body (2.3) are 11 mm, the third winding length (2.5) of the antenna body (2.3) is 9.5 mm, and the total length of the antenna body (2.3) is 138.2 mm; The antenna end (2.6) has a line width of 0.8 mm and a line length of 4.3 mm.

4. The onboard antenna according to claim 1, characterized in that: The antenna body (2.3) adjusts the routing shape and length according to the actual space and the required frequency band, and performs clearance processing around it. By adjusting the winding width (2.4) and winding length (2.5) of the antenna body (2.3), the required frequency band and capacitive reactance of the antenna are adjusted, the return loss is optimized, and the bandwidth is increased.

5. The onboard antenna according to claim 1, characterized in that: The antenna is made of FR4 copper foil etched directly on the module motherboard (1.4).

6. A detachable RF module for smoke sensing, characterized in that: Comprising the onboard antenna according to any one of claims 1 to 5, the detachable RF module applied to the smoke sensor further comprises: A radio frequency module (1.1) is arranged on a module main board (1.4), the radio frequency module (1.1) communicates with the outside world via an antenna, and the module main board (1.4) is detachably connected to the smoke sensor; Interface pin (1.3), an interface designed inside the smoke detector, and the interface pin (1.3) is connected to the interface.

7. The detachable RF module for smoke sensing according to claim 6, characterized in that: The radio frequency module (1.1) contains a radio frequency transceiver circuit, including a transmitting module and a receiving module, and a power management system is arranged inside the smoke detector.

8. The detachable RF module for smoke sensing according to claim 6, characterized in that: The module mainboard (1.4) is detachably connected to the smoke sensor via a connection structure, the smoke sensor comprising a housing (3), and the connection structure comprising: Two groups of left-right symmetrical limiter components (4), the left limiter component (4) includes: A first fixing block (41) is fixedly connected to the left inner wall of the housing (3), and a sliding groove (42) is provided at the upper right end of the first fixing block (41); A limit block (43), wherein an extension portion (431) is integrally provided at the right lower end of the limit block (43), the extension portion (431) is slidably connected in the slide groove (42) along the left-right direction, a first spring (46) is provided between the extension portion (431) and the inner wall of the slide groove (42), and a slope portion (432) which is higher on the left and lower on the right is provided on the left side of the limit block (43); the right side of the upper end portion of the limit block (43) located at the extension portion (431) is a clamping surface (433); The vertical screw rod (44) is threadedly connected to the first fixing block (41), and the vertical screw rod (44) passes through the first fixing block (41). A spherical surface (45) is arranged on the upper end of the vertical screw rod (44), and the spherical surface (45) contacts with an inclined surface portion (432).

Images