Radio frequency antenna device suitable for complex industrial site and assembling method thereof

Abstract

The invention discloses a radio frequency antenna device suitable for a complex industrial site, which comprises an outer layer protective shell with windows on the periphery, an inner layer protective shell with a hole in the center arranged in the outer layer protective shell, and a sealing O-shaped ring arranged between the front end of the outer wall of the inner layer protective shell and the inner wall of the outer layer protective shell, after the inner-layer protective shell and the outer-layer protective shell are pressed tightly through the pressing ring, the pressing ring is fixed to the outer-layer protective shell through the fixing bolt, the spring antenna is sealed in a center opening of the inner-layer protective shell in a pouring mode through pouring sealant, and the front end of the spring antenna is fixedly connected with the antenna extension line. According to the radio frequency antenna device disclosed by the invention, a double-layer protection scheme of combining the outer-layer protection shell and the inner-layer protection shell is adopted for the radio frequency antenna, so that the radio frequency antenna device can well meet the protection requirements of complex industrial sites, and has the advantages of good protection effect and small size.

Description

Technical Field

[0001] The present invention belongs to the field of radio frequency antennas, and in particular relates to a radio frequency antenna device in the field suitable for complex industrial sites such as strong vibration, impact, and water immersion, and an assembly method thereof. Background Art

[0002] With the development of wireless communication technology, wireless sensors and wireless sensor network technology are increasingly widely used in the industrial field. Sensors used in the industrial field are mainly used for equipment status monitoring and on-site environmental monitoring in industrial sites. Under certain complex industrial environmental conditions, after the wireless sensor is installed, its application environment will be subject to strong vibration, abnormal impact of foreign objects on the sensor during the operation of industrial equipment or industrial production, environmental water spray or pressurized water immersion and other harsh working conditions. The above complex application conditions require that the wireless sensor must be effectively protected to meet the requirements of long-term stable and reliable operation.

[0003] The protection of the sensor housing itself can be made of metal, which is relatively easy to design and implement. However, the transmission of wireless sensor signals requires the RF antenna to radiate electromagnetic wave signals to the external space environment. Therefore, the protection design of the RF antenna cannot use a completely sealed metal structure. The protection solution of the RF antenna is the focus of the wireless sensor protection design.

[0004] At present, the wireless sensor antenna protection solutions used in the above complex environment fields mostly use small-sized flexible rubber stick antennas with strong adaptability, small-sized ceramic antennas, etc., or use protective hydraulic hoses to seal and protect ordinary antennas. Small flexible rubber stick antennas have certain vibration resistance and waterproof capabilities, but their anti-collision capabilities are insufficient. For minor collisions, the rubber stick has a certain elasticity, which can realize the rebound of the antenna after being deformed by external force, but for medium-intensity collisions, it will cause damage to the antenna. Small ceramic antennas, due to their smaller size, although the probability of being subjected to external collisions will be greatly reduced, but for medium-intensity collisions, the antenna will also be damaged. Antennas sealed with protective hydraulic hoses have the defect of large volume. Although they can withstand medium-intensity collisions to a certain extent, they are large in size and have a high probability of being subjected to abnormal collisions. In addition, the antenna extension line in the hose will swing with the hose under vibration, which can easily cause the antenna extension line to fail.

[0005] In summary, the current antenna protection solutions have defects such as insufficient anti-collision capability and poor adaptability in long-term strong vibration environments. Antenna failure will have an adverse impact on the reliable operation of wireless sensor networks. Currently, there is no technology or method to achieve small and highly protected RF antennas in complex industrial environments. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a radio frequency antenna device and an assembly method thereof which can be well applied to complex industrial environments for a long time, and has the characteristics of small size, small influence on the outward radiation transmission of radio frequency signals, strong anti-collision and anti-vibration capabilities, and good waterproof performance.

[0007] The present invention adopts the following technical solution: A radio frequency antenna device suitable for complex industrial sites, the improvement of which lies in: comprising an outer protective shell with windows on all sides, an inner protective shell with a central opening arranged inside the outer protective shell, a sealing O-ring arranged between the front end of the outer wall of the inner protective shell and the inner wall of the outer protective shell, the inner protective shell and the outer protective shell are pressed together by a pressure ring, and then the pressure ring is fixed to the outer protective shell by fixing bolts, a spring antenna is potted in the central opening of the inner protective shell by potting glue, and the front end of the spring antenna is fixedly connected to an antenna extension line.

[0008] Furthermore, the outer protective shell adopts a cage-like structure and is made of stainless steel.

[0009] Furthermore, the inner protective shell is cylindrical and made of non-metallic insulating material.

[0010] Furthermore, a sealing gasket is installed on the front end of the outer wall of the outer protective shell.

[0011] Furthermore, a pipe thread interface is provided at the front end of the outer wall of the outer protective shell.

[0012] Furthermore, a radial groove for accommodating a sealing O-ring is provided at the front end of the outer wall of the inner protective shell.

[0013] Furthermore, the antenna extension line is connected to the spring antenna by welding.

[0014] Furthermore, the spring antenna is welded and connected to the radio frequency antenna centrally installed in the inner protective shell, and the antenna extension line extends out of the outer protective shell and is assembled and connected to the radio frequency circuit board.

[0015] An assembly method is applicable to the above-mentioned radio frequency antenna device, and its improvement lies in that it comprises the following steps: Step 1, insert the sealing O-ring into the radial groove at the front end of the outer wall of the inner protective shell; Step 2, apply silicone grease on the surface of the sealing O-ring, and install the inner protective shell into the outer protective shell; Step 3: After pressing the inner protective shell and the outer protective shell with a pressing ring, the pressing ring and the outer protective shell are fixedly connected with fixing bolts; Step 4, sleeve the sealing gasket onto the sealing end surface at the front end of the outer wall of the outer protective shell; Step 5, solder the spring antenna and antenna extension wire together; Step 6, install the spring antenna into the central opening of the inner protective shell; Step 7, potting the spring antenna in the central opening of the inner protective shell with potting glue; Step 8: Complete the assembly after the potting glue is completely cured.

[0016] The beneficial effects of the present invention are: The radio frequency antenna device disclosed in the present invention adopts a double-layer protection scheme of an outer protective shell and an inner protective shell for the radio frequency antenna, which can be well adapted to the protection requirements of complex industrial sites and has the advantages of good protection effect and small size. The outer protective shell with a cage-shaped window has little effect on the transmission of radio frequency signals, and can maximize the protection performance of the radio frequency antenna while ensuring the coverage range of the wireless sensor network.

[0017] A sealing O-ring is used to seal the inner protective shell and the outer protective shell, and the spring antenna is potted in the central opening of the inner protective shell by potting glue. These designs make the radio frequency antenna device disclosed in the present invention have the characteristics of good waterproof performance, strong vibration resistance and good adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the radio frequency antenna device disclosed in Example 1 of the present invention.

[0019] Figure numerals: 1—outer protective shell, 2—inner protective shell, 3—pressure ring, 4—sealing O-ring, 5—sealing gasket, 6—spring antenna, 7—antenna extension line, 8—fixing bolt, 9—potting glue. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] Embodiment 1, as Figure 1 As shown, this embodiment discloses a radio frequency antenna device suitable for complex industrial sites, including an outer protective shell 1 with windows on all sides, an inner protective shell 2 with a central opening arranged inside the outer protective shell, a sealing O-ring 4 is arranged between the front end of the outer wall of the inner protective shell and the inner wall of the outer protective shell, the inner protective shell and the outer protective shell are pressed together by a pressure ring 3, and then the pressure ring is fixed to the outer protective shell by a fixing bolt 8, a spring antenna 6 is potted in the central opening of the inner protective shell by a potting glue 9 to ensure its vibration resistance, and the front end of the spring antenna is fixedly connected to the antenna extension line 7 by welding.

[0022] A double-layer protection structure is used to protect the RF antenna. The outer protective shell adopts a cage-like structure and is made of stainless steel. As the first layer of protection for the RF antenna, the window of the outer metal protective shell can ensure that the RF signal is not completely shielded. The signal on the RF antenna can be effectively transmitted to the outside through penetration and diffraction. The hardness and collision resistance of the outer metal protective shell are high, and it can withstand the impact of abnormal objects of medium strength or above. The inner protective shell is cylindrical and made of non-metallic insulating materials with good strength and toughness. The inner protective shell is embedded in the outer metal protective shell to avoid direct collision with external abnormal objects. Even if a small object collides with the inner protective shell at the window of the outer metal protective shell, it will basically not cause damage to the inner protective shell.

[0023] When the inner cylindrical protective shell is installed in the outer metal protective shell, it is radially sealed by the sealing O-ring to ensure high pressure-bearing and waterproof sealing capabilities. The inner cylindrical protective shell and the outer metal protective shell are connected and fixed by a pressure ring to ensure strong vibration resistance after overall installation.

[0024] A pipe thread interface is provided at the front end of the outer wall of the outer protective shell. A sealing gasket 5 is installed on the front end of the outer wall of the outer protective shell. The outer metal protective shell is fixedly connected to the sensor protective shell in the form of a pipe thread interface, and is waterproofly sealed by a flat sealing gasket.

[0025] A radial groove for accommodating a sealing O-ring is arranged at the front end of the outer wall of the inner protective shell.

[0026] The RF antenna uses a small spring antenna to achieve outward radiation transmission of the RF signal. The spring antenna is welded to the RF antenna with an SMA connector or other connectors. The RF antenna is centrally installed in the inner cylindrical protective shell, and the antenna extension line extends out of the outer protective shell and is assembled and connected to the RF circuit board.

[0027] This embodiment also discloses an assembly method, which is applicable to the above-mentioned radio frequency antenna device, and includes the following steps: Step 1, insert the sealing O-ring into the radial groove at the front end of the outer wall of the inner protective shell; Step 2: Apply a proper amount of silicone grease on the surface of the sealing O-ring, and install the inner protective shell into the outer protective shell; Step 3: After the inner protective shell and the outer protective shell are pressed tightly with a pressure ring, the pressure ring and the outer protective shell are fixedly connected with fixing bolts to ensure that the inner protective shell is reliably fixed after being installed into the outer protective shell; Step 4, sleeve the sealing gasket onto the sealing end surface at the front end of the outer wall of the outer protective shell; Step 5: Solder the spring antenna and antenna extension wire to ensure a reliable connection; Step 6, install the spring antenna into the central opening of the inner protective shell; Step 7, potting the spring antenna in the central opening of the inner protective shell with potting glue; Step 8: After the potting glue is completely cured, the assembly is completed and the RF module can be connected for use.

Claims

1. A radio frequency antenna device suitable for complex industrial sites, characterized in that: The invention comprises an outer protective shell with windows on all sides, an inner protective shell with a central opening arranged inside the outer protective shell, a sealing O-ring arranged between the front end of the outer wall of the inner protective shell and the inner wall of the outer protective shell, the inner protective shell and the outer protective shell are pressed together by a pressure ring, and then the pressure ring is fixed to the outer protective shell by fixing bolts, the spring antenna is potted in the central opening of the inner protective shell by potting glue, and the front end of the spring antenna is fixedly connected to the antenna extension line.

2. The radio frequency antenna device suitable for complex industrial sites according to claim 1, characterized in that: The outer protective shell adopts a cage-like structure and is made of stainless steel.

3. The radio frequency antenna device suitable for complex industrial sites according to claim 1, characterized in that: The inner protective shell is cylindrical and is made of non-metallic insulating material.

4. The radio frequency antenna device suitable for complex industrial sites according to claim 1, characterized in that: A sealing gasket is installed on the front end of the outer wall of the outer protective shell.

5. The radio frequency antenna device suitable for complex industrial sites according to claim 1, characterized in that: A pipe thread interface is arranged at the front end of the outer wall of the outer protective shell.

6. The radio frequency antenna device suitable for complex industrial sites according to claim 4, characterized in that: A radial groove for accommodating a sealing O-ring is arranged at the front end of the outer wall of the inner protective shell.

7. The radio frequency antenna device suitable for complex industrial sites according to claim 6, characterized in that: The antenna extension wire is connected to the spring antenna by welding.

8. The radio frequency antenna device suitable for complex industrial sites according to claim 1, characterized in that: The spring antenna is welded and connected to the radio frequency antenna centrally installed in the inner protective shell, and the antenna extension line extends out of the outer protective shell and is assembled and connected with the radio frequency circuit board.

9. An assembly method, applicable to the radio frequency antenna device according to claim 7, characterized in that: The steps include: Step 1, insert the sealing O-ring into the radial groove at the front end of the outer wall of the inner protective shell; Step 2, apply silicone grease on the surface of the sealing O-ring, and install the inner protective shell into the outer protective shell; Step 3, after pressing the inner protective shell and the outer protective shell with a pressing ring, the pressing ring and the outer protective shell are fixedly connected with fixing bolts; Step 4, sleeve the sealing gasket onto the sealing end surface at the front end of the outer wall of the outer protective shell; Step 5, solder the spring antenna and antenna extension wire together; Step 6, install the spring antenna into the central opening of the inner protective shell; Step 7, potting the spring antenna in the central opening of the inner protective shell with potting glue; Step 8: Complete the assembly after the potting glue is completely cured.

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