Trigger type key sealing structure and laser gas detection device

Abstract

The application relates to the technical field of handheld devices, and provides a trigger type key sealing structure and a laser gas detection device, which comprises a first shell and a second shell, a groove is arranged on the first shell, the first shell and the second shell are tightly buckled and enclosed to form a containing cavity through a sealing ring in the groove, silica gel keys, a key circuit board and a metal sheet support are arranged in the containing cavity, the key circuit board is fixed on the metal sheet support through a first screw, the metal sheet support is fixed on a mounting column on the inner side of the first shell through a second screw, a key window is arranged on the first shell, the silica gel keys are embedded in the key window, the metal sheet support and the key circuit board support the sealing lip of the silica gel keys in the direction perpendicular to the plane where the key window is located, so that the sealing lip is pressed and abuts against the inner wall of the key window, and the pressing contact point on the inner side of the silica gel key abuts against the trigger contact point of the key circuit board. The application can control the fixed compression amount of the sealing lip and improve the waterproof capability.

Description

Technical Field

[0001] This application relates to the field of handheld device technology, and in particular to a trigger-type button sealing structure and a laser gas detection device. Background Technology

[0002] Currently, handheld instruments, laser telemetry instruments and other equipment use trigger-type buttons. Trigger-type buttons are movable and pressable structures, and it is difficult to effectively seal the gaps between the housing and the assembly gaps of the buttons. Moisture and dust can easily enter the inside of the housing, causing corrosion of the button circuit board and short circuit failures.

[0003] Existing trigger buttons often use the method of sealing by the interference fit of silicone itself. However, this sealing method cannot precisely control the amount of compression, and long-term use can easily cause silicone fatigue, which not only makes the button feel too hard and the rebound too sluggish, but also leads to seal failure. Summary of the Invention

[0004] To address the aforementioned issues, this application proposes a trigger-type button sealing structure and a laser gas detection device. This effectively controls the sealing compression in the trigger-type button structure, avoiding seal failure caused by silicone fatigue after prolonged pressure. This improves the device's waterproof and dustproof capabilities, stabilizes the protection level, and enhances the stability of the circuit board's operation. The specific technical solution is as follows: In a first aspect, embodiments of this application propose a trigger-type button sealing structure, including a first housing, a second housing, a silicone button, a button circuit board, a sheet metal bracket, and a sealing ring; The first housing has a groove, and the sealing ring is provided in the groove. The first housing and the second housing are tightly fastened and enclosed by the sealing ring to form a receiving cavity. The receiving cavity is provided with the silicone button, the button circuit board and the sheet metal bracket. The button circuit board is fixed to the sheet metal bracket by a first screw, and the sheet metal bracket is locked to the mounting post inside the first housing by a second screw. The first housing has a button window, the silicone button is embedded in the button window, and the sealing lip of the silicone button is in close contact with the inner wall of the button window; The sheet metal bracket and the button circuit board support the sealing lip of the silicone button in a direction perpendicular to the plane where the button window is located, so that the sealing lip of the silicone button is pressed against the inner wall of the button window, and the pressing contact on the inner side of the silicone button abuts against the trigger contact of the button circuit board.

[0005] Furthermore, the assembly compression of the sealing lip of the silicone button is determined by a closed dimensional chain formed by the height of the mounting post, the thickness of the sheet metal bracket, and the height of the sealing lip.

[0006] Furthermore, the assembly compression of the sealing lip of the silicone button is 0.4mm to 0.6mm, so that the sealing lip of the silicone button forms an interference fit with the first housing.

[0007] Furthermore, the inner side of the first housing is provided with an integrally injection-molded mounting post for locking and positioning the sheet metal bracket.

[0008] Furthermore, the sheet metal bracket is a rigid metal bracket, and the sheet metal bracket is provided with screw holes and limiting slots, the limiting slots limiting the position of the button circuit board.

[0009] Furthermore, the button circuit board is a flexible PCB board or a rigid PCB board used to collect trigger signal. The non-contact surface of the button circuit board is attached to the sheet metal bracket, and the contact point of the contact surface abuts against the pressing contact on the inner side of the silicone button.

[0010] Furthermore, the silicone button is integrally molded from elastic silicone material.

[0011] Furthermore, the inner side of the first housing is also provided with a plurality of integrally injection molded housing connecting posts, which are used to lock and fix the first housing and the second housing together by a plurality of third screws.

[0012] Secondly, embodiments of this application propose a laser gas detection device, including a laser emitter and a laser detector. The device is also equipped with a trigger-type button sealing structure as described in the first aspect. The first housing and the second housing are the outer shell of the laser gas detection device, and the button circuit board is electrically connected to the control circuit board inside the laser gas detection device.

[0013] This application proposes a trigger-type button sealing structure, which has the following beneficial effects: This trigger-type button sealing structure includes a first housing with a groove and a sealing ring, a second housing, a silicone button, a button circuit board, and a sheet metal bracket. The first housing and the second housing are fastened together by the sealing ring to form a receiving cavity. The button circuit board is fixed on the sheet metal bracket, and the sheet metal bracket is locked to the mounting post inside the first housing. The silicone button is embedded in the button window. With the help of the sheet metal bracket and the button circuit board, the sealing lip of the silicone button is supported, making it press tightly against the inner wall of the button window. The inner pressing contact of the silicone button is connected to the trigger contact of the button circuit board. This structure can precisely control the compression of the sealing lip. Combined with the sealing ring at the housing connection, it forms a double seal, effectively preventing the intrusion of water vapor and dust, slowing down the fatigue aging of silicone, ensuring stable button feel, and improving the waterproof and dustproof performance of the button position of the device. Attached Figure Description

[0014] Figure 1This is a first structural schematic diagram of a trigger-type button sealing structure provided in this application; Figure 2 This is a second structural schematic diagram of a trigger-type button sealing structure provided in this application.

[0015] Reference numerals: 1. First housing; 2. Silicone button; 3. Button circuit board; 4. First screw; 5. Sheet metal bracket; 6. Second screw; 7. Second housing; 8. Third screw; 9. Button window; 10. Mounting post; 11. Groove. Detailed Implementation

[0016] To make the technical problems solved by this application, the technical solutions adopted, and the technical effects achieved clearer, this application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit it.

[0017] Existing trigger-type buttons rely solely on the elasticity of silicone for sealing, resulting in uncontrollable compression and silicone fatigue after prolonged pressing. This allows moisture to easily seep into the button window, damaging the circuit board. This application provides a trigger-type button sealing structure that solves the problems of uncontrollable sealing compression and silicone fatigue leading to sealing failure in existing trigger-type button structures.

[0018] Example 1

[0019] This application provides a trigger-type button sealing structure, such as Figure 1-2 As shown, it may include a first housing 1, a second housing 7, a silicone button 2, a button circuit board 3, a sheet metal bracket 5, and a sealing ring. The first housing 1 and the second housing 7 can be made of ABS material, which has good insulation and high structural strength.

[0020] A groove 11 is formed on the mating end face of the first housing 1, and a sealing ring is embedded in the groove 11. The first housing 1 and the second housing 7 can be tightly fastened and enclosed by the sealing ring to form a receiving cavity. The end face of the second housing 7 is pressed against the sealing ring to achieve static sealing protection. The receiving cavity is equipped with a silicone button 2, a button circuit board 3, and a sheet metal bracket 5.

[0021] In one embodiment, the first housing 1 and the second housing 7 are snapped together to form a complete outer shell for the handheld trigger device. The inner side of the first housing 1 may also have multiple integrally injection-molded housing connecting posts, allowing the first housing 1 and the second housing 7 to be locked and fixed together by a predetermined number of third screws 8. For example, the inner side of the first housing 1 has six integrally injection-molded housing connecting posts, and the first housing 1 and the second housing 7 are locked and fixed together by six screws. In another embodiment, the first housing 1 and the second housing 7 can also be locked together by snap-fit ​​fasteners.

[0022] The button circuit board 3 can be fixed to the flat, mating end surface of the sheet metal bracket 5 by the first screw 4, or the button circuit board 3 can also be rigidly fixed to the sheet metal bracket 5 by snap-fit. The sheet metal bracket 5 is locked and fixed to the mounting post 10 inside the first housing 1 by the second screw 6.

[0023] In one embodiment, the sheet metal bracket 5 is a rigid metal bracket, integrally formed with screw holes and limiting slots. The limiting slots are used to secure the edge of the button circuit board 3, thus limiting the position of the button circuit board 3. The sheet metal bracket can achieve both flatness constraint and position limitation of the button circuit board.

[0024] The first housing 1 has a button window 9, and a silicone button 2 is embedded in the button window 9. The sealing lip of the silicone button 2 is in close contact with the inner wall of the button window 9 to form a complete closed-loop sealing surface.

[0025] The sheet metal bracket 5 and the button circuit board 3 support the sealing lip of the silicone button 2 in a direction perpendicular to the plane of the button window 9, so that the sealing lip of the silicone button 2 is pressed tightly against the inner wall of the button window 9, and the pressing contact on the inner side of the silicone button 2 abuts against the trigger contact of the button circuit board 3. The cross-section of the sealing lip can be quadrilateral.

[0026] In other words, the core of this structure adopts the rigid reverse top support sealing principle: the sheet metal bracket and the button circuit board form a rigid support base. When pressure is applied to the trigger button, the inner wall of the first housing can apply pressure along the axial direction of the button window to the sealing lip of the silicone button. The sheet metal bracket provides reverse rigid support to the button circuit board. Under the bidirectional extrusion action, the silicone button lip completely fills the assembly gap between the button window and the housing, forming a continuous closed-loop interference sealing surface, preventing water and dust from entering the equipment from the assembly gap of the trigger button, thus achieving an IP68 dustproof and waterproof rating.

[0027] The assembly compression of the sealing lip of the silicone button 2 is determined by the closed dimensional chain formed by the height of the mounting post 10, the thickness of the sheet metal bracket 5, and the height of the sealing lip. In other words, the assembly compression of the sealing lip of the silicone button 2 can be determined by the dimensional fit between the height of the mounting post 10, the thickness of the sheet metal bracket 5, and the height of the sealing lip. Thus, by transforming the experience-dependent, non-standard silicone interference seal into a rigid support seal structure with controllable quantities, calculable parameters, and replicable mass production capabilities, the long-standing pain point of poor waterproofing consistency in trigger-activated buttons in the industry can be solved.

[0028] The compression amount of the sealing lip of the silicone button 2 is 0.4mm to 0.6mm. Preferably, the compression amount of the sealing lip of the silicone button 2 is 0.5mm. This compression amount is the optimal fitting parameter, allowing the sealing lip of the silicone button 2 to form an interference seal with the first housing 1. The 0.5mm compression amount can fill the housing fit gap, meeting the interference seal requirements of IP68 waterproof and dustproof, without generating excessive extrusion force, ensuring that the trigger button is easy to press and has a smooth rebound. At the same time, it can effectively prevent permanent deformation of silicone due to long-term compression, significantly extending the service life of the seal. Therefore, the 0.5mm quantitative compression of the silicone button at the button window position achieves a dedicated seal for dynamic movement gaps, blocking the core water ingress point of the button's reciprocating movement, and providing protection in combination with the housing seal.

[0029] In one embodiment, the mounting post 10 inside the first housing 1 is integrally injection molded from the first housing 1 and is used to lock and position the sheet metal bracket 5. This ensures the verticality of the sheet metal bracket assembly and avoids misalignment during assembly, which could lead to deviations in compression.

[0030] In one embodiment, the sheet metal bracket 5 can be formed by stamping and bending 1mm cold-rolled steel plate. One side is provided with a limit slot and locking boss for the button circuit board to achieve flat and rigid fixation of the button circuit board. The other side is locked to the housing mounting column by screws, which serves as the reverse force reference for sealing and extrusion, ensuring that the extrusion load is evenly distributed and preventing the circuit board from being deformed by pressure.

[0031] The button circuit board 3 can be a flexible or rigid PCB board used to collect trigger signals. The non-contact surface of the button circuit board 3 is attached to the sheet metal bracket 5, and the contact points on the contact surface abut against the pressing contacts on the inner side of the silicone button 2. The sheet metal bracket ensures the flatness of the button circuit board, preventing it from warping under pressure, and ensuring that the compression of each sealing lip is uniform.

[0032] The silicone button 2 can be integrally molded from elastic silicone material. The inner side of the silicone button 2 has pressing protrusions that correspond to the contacts on the button circuit board 3 for triggering. A continuous annular sealing lip surrounds the outer edge of the silicone button 2. The height of the sealing lip has been dimensionally calibrated to precisely generate 0.5mm axial compression after the housing is closed and locked. Relying on the elastic rebound force of the silicone rubber itself, a long-term interference seal is maintained, preventing both excessive compression causing trigger pressing difficulties and jamming, and insufficient compression causing leaks due to poor sealing. In one embodiment, the silicone button 2 can be integrally molded from Shore A50 silicone rubber.

[0033] Assembly process: First, fix the button circuit board to the sheet metal bracket. Then, embed the silicone button into the button window of the first housing. Next, attach the sheet metal bracket to the first housing using mounting posts. Finally, lock the first and second housings together. The trigger-type silicone button, activated by finger pressure, conducts a signal, preventing external rainwater and dust from entering the cavity through the button window gaps. Its waterproof and dustproof performance remains undiminished. Even during equipment vibration or drops, the sheet metal bracket keeps the circuit board from shifting.

[0034] This application uses a single stamped sheet metal bracket to integrate multiple functions. It can serve as a rigid pressure support for silicone interference seals, limit and position the button contacts of the PCB board, and maintain the sealing compression by shock resistance and locking. It achieves accurate assembly by relying on irregular notches. With a low-cost, multi-functional sheet metal integrated design, it solves the problems of sealing pressure, circuit board positioning and fixation, and vibration resistance and reliability in the small space of the trigger.

[0035] Example 2

[0036] This application also provides a laser gas detection device, including a laser emitter, a laser detector, and a control circuit board. The device is also equipped with the trigger-type button sealing structure in Embodiment 1. The first housing 1 and the second housing 7 are the outer shell of the laser gas detection device. The button circuit board is electrically connected to the control circuit board inside the laser gas detection device. By pressing the trigger-type silicone button, the device can be started / stopped, the detection is triggered, and the parameters are switched.

[0037] The device underwent the following overall reliability tests: 1. IP68 Protection Test: After continuous immersion in 1 meter of water for 30 minutes and high-pressure spray testing, no water or dust entered the device, and the circuit showed no corrosion or short circuit faults. 2. Silicone Button Durability Test: After repeated pressing of the trigger button 100,000 times, the button's tactile feedback remained unchanged, there was no jamming, the sealing lip showed no deformation or seal failure, and the waterproof performance remained unchanged. 3. Shock and Drop Test: After normal operating condition vibration and a 1.5-meter drop test, the circuit board showed no displacement, the sealing structure remained intact, and the protective performance and button function remained stable.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications to the technical solutions described in the foregoing embodiments, or equivalent substitutions for some or all of the technical features, do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A trigger-type button sealing structure, characterized in that, It includes a first housing (1), a second housing (7), a silicone button (2), a button circuit board (3), a sheet metal bracket (5), and a sealing ring; The first housing (1) is provided with a groove (11), and the sealing ring is provided in the groove (11). The first housing (1) and the second housing (7) are tightly fastened and enclosed by the sealing ring to form a receiving cavity. The receiving cavity is provided with the silicone button (2), the button circuit board (3) and the sheet metal bracket (5). The button circuit board (3) is fixed to the sheet metal bracket (5) by the first screw (4), and the sheet metal bracket (5) is locked to the mounting post (10) inside the first housing (1) by the second screw (6). The first housing (1) has a button window (9) and the silicone button (2) is embedded in the button window (9). The sealing lip of the silicone button (2) is in close contact with the inner wall of the button window (9). The sheet metal bracket (5) and the button circuit board (3) support the sealing lip of the silicone button (2) in a direction perpendicular to the plane of the button window (9), so that the sealing lip of the silicone button (2) is pressed against the inner wall of the button window (9), and the pressing contact on the inner side of the silicone button (2) abuts against the trigger contact of the button circuit board (3).

2. The trigger-type button sealing structure according to claim 1, characterized in that, The assembly compression of the sealing lip of the silicone button (2) is determined by a closed dimensional chain formed by the height of the mounting post (10), the thickness of the sheet metal bracket (5), and the height of the sealing lip.

3. The trigger-type button sealing structure according to claim 2, characterized in that, The assembly compression of the sealing lip of the silicone button (2) is 0.4 mm to 0.6 mm, so that the sealing lip of the silicone button (2) forms an interference fit with the first housing (1).

4. The trigger-type button sealing structure according to claim 1, characterized in that, The first housing (1) has an integrally injection-molded mounting post (10) on its inner side, which is used to lock and position the sheet metal bracket (5).

5. The trigger-type button sealing structure according to claim 1, characterized in that, The sheet metal bracket (5) is a rigid metal bracket. The sheet metal bracket (5) is provided with screw holes and a limiting slot. The limiting slot limits the position of the button circuit board (3).

6. The trigger-type button sealing structure according to claim 1, characterized in that, The button circuit board (3) is a flexible PCB board or a rigid PCB board used to collect trigger signals. The non-contact surface of the button circuit board (3) is attached to the sheet metal bracket (5), and the contact point of the contact surface abuts against the pressing contact point inside the silicone button (2).

7. The trigger-type button sealing structure according to claim 1, characterized in that, The silicone button (2) is integrally molded from elastic silicone material.

8. The trigger-type button sealing structure according to claim 1, characterized in that, The inner side of the first housing (1) is also provided with a plurality of integrally injection molded housing connecting columns, which are used to lock and fix the first housing (1) and the second housing (7) by a plurality of third screws (8).

9. A laser gas detection device, comprising a laser emitter and a laser detector, characterized in that, The device is also equipped with a trigger-type button sealing structure as described in any one of claims 1-8, wherein the first housing (1) and the second housing (7) are the outer shell of the laser gas detection device, and the button circuit board (3) is electrically connected to the control circuit board inside the laser gas detection device.

Images