A manhole cover detection switch

Abstract

The utility model relates to cable accessory technical field, concretely is a well lid detection switch, including the trigger subassembly of vertical arrangement, and the trigger subassembly bottom is connected on the well lid through the fixed base, the trigger subassembly includes the communication line, cable sleeve, reset spring and protection sleeve from inside to outside in proper order and is connected, and the protection pipe top end connects the trigger head, and the reset spring abuts on the trigger head lower bottom surface and fixed base upper surface, and the ball switch in the trigger head inside is connected with the communication line, the ball switch is fixed on the switch board, and is equipped with the limit hole on the switch board, the switch fixed base top is equipped with the opening, and the bottom is equipped with the limit foot, and the position of limit foot and limit hole corresponds. Through the cooperation between limit foot and limit hole, realize self -positioning, ensure that the horizontal condition during the installation of ball switch satisfies the working demand.

Description

Technical Field

[0001] This utility model relates to the field of cable accessories technology, specifically a manhole cover detection switch. Background Technology

[0002] The statements in this section are merely background information related to this utility model and do not necessarily constitute prior art.

[0003] To prevent damage to the cables inside the cable well, a detection switch is installed on the well cover. When the detection switch is triggered, an alarm signal is transmitted to the back-end management platform, allowing staff to quickly locate the cable well where the alarm occurred.

[0004] To ensure reliable operation of the detection switch, improve the triggering effect at multiple angles, and reduce false alarms, existing technology uses a ball switch as the triggering element. A protective tube and protective sleeve with a reset spring are installed on the outside of the ball switch, so that impacts from multiple directions can be absorbed by the spring, protective tube, and protective sleeve. False alarms will not be affected by the shape of the bottom of the manhole cover above, and the impact protection performance meets the usage requirements.

[0005] While existing technologies have solved the problem of multi-angle omnidirectional triggering sensing, they still suffer from drawbacks in actual mass production and application, such as complex processing, high cost, low efficiency, poor protection, and insufficient reliability. These drawbacks are as follows:

[0006] Missing installation limit of ball switch: Due to the lack of an effective limit structure, the ball switch is prone to offset or tilting during installation, which will cause the trigger angle to deviate and affect the detection accuracy.

[0007] Design flaws of the switch mounting base: The mounting base adopts a closed structure. During subsequent potting and sealing, the adhesive cannot flow fully into the cavity at the bottom of the metal trigger head, resulting in poor sealing and easy intrusion of moisture into the interior.

[0008] Inappropriate communication cable layout: The communication cable is connected to the detection switch via a bend in the conduit. Due to limitations in thread length and depth, the cable can only be fixed along the direction of the bend joint. When installing to the manhole cover, the cable's freedom of movement before entering the detection switch is restricted, leading to installation difficulties, cable redundancy, tangling, and other problems, which can easily cause signal transmission interruptions. Utility Model Content

[0009] In order to solve the technical problems existing in the background art, the present invention provides a manhole cover detection switch, which improves the performance of assembly, sealing and cable arrangement by optimizing the switch fixing seat, switch plate and fixing base of the ball switch.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] This utility model provides a manhole cover detection switch, including a vertically arranged trigger assembly. The bottom of the trigger assembly is connected to the manhole cover via a fixed base. The trigger assembly includes a communication line, a cable sleeve, a return spring, and a protective sleeve, which are sequentially connected from the inside to the outside. The top of the protective sleeve is connected to a trigger head. The return spring abuts against the bottom surface of the trigger head and the upper surface of the fixed base. The ball switch inside the trigger head is connected to the communication line.

[0012] The ball switch is fixed on the switch plate, which has a limit hole; the upper surface of the switch plate has a switch mounting base, which has an opening at the top and a limit foot at the bottom, with the limit foot corresponding to the position of the limit hole.

[0013] Furthermore, the manhole cover is equipped with a fixed base, which is connected to the protective sleeve and triggering component via a waterproof connector.

[0014] Furthermore, the fixed base is plate-shaped and has connection holes for connecting the manhole cover and the waterproof connector, and a through hole in the middle to allow the waterproof connector and trigger assembly to pass through.

[0015] Furthermore, the manhole cover is equipped with a retaining sleeve, which is used to protect the waterproof joint.

[0016] Furthermore, the top of the protective sleeve is connected to the trigger head, and an internal space is formed to accommodate the ball switch.

[0017] Furthermore, the bottom end of the protective sleeve passes through the fixing sleeve and is connected to the fixing base via a waterproof connector.

[0018] Furthermore, the waterproof connector is attached to the fixed base and has a filter circuit board inside. One end is connected to the protective sleeve, and the other end is connected to the pipe cap and hose connector.

[0019] Furthermore, the hose connector is provided with a hole for potting and sealing, which is used to seal the filter circuit board by potting.

[0020] Furthermore, one end of the communication line is connected to a ball switch, and the other end is connected to a cable via a filter circuit board.

[0021] Furthermore, the cable passes through a flexible conduit and a cap, and is connected to the communication line via a filter circuit board.

[0022] Compared with existing technologies, one or more of the above technical solutions have the following beneficial effects:

[0023] 1. In response to the problem that ball switches are prone to shifting or tilting during installation in existing technologies, this solution sets a limiting structure between the switch plate and the switch mounting base of the ball switch. Through the cooperation between the limiting feet and the limiting holes, self-positioning is achieved, ensuring that the horizontal position of the ball switch meets the working requirements during installation.

[0024] 2. In the existing technology, the switch holder of the ball switch adopts a sealed structure, which makes it difficult for the sealing adhesive to flow into the trigger head cavity, resulting in poor sealing. The solution provides an opening at the top of the switch holder, which makes it easier for the sealing adhesive to flow into the bottom cavity of the trigger head, thus achieving a better sealing effect.

[0025] 3. In response to the problem in existing technologies where communication cables are connected to the detection switch via a bend in the conduit, which restricts the cable's freedom of movement, this solution eliminates the bend in the conduit structure and replaces it with a flexible conduit connector and cap. This eliminates the restriction on the cable's freedom of movement before it enters the detection switch, reduces the cable winding before entering the switch, and lowers the cable redundancy.

[0026] 4. The original fixed base that needed to be welded into components was changed to a flat plate structure, which reduced complex processing such as welding and threading, reduced manufacturing processes and costs, and improved production efficiency.

[0027] 5. Furthermore, by adding a filter circuit board, noise generated by the vibration of the external manhole cover is filtered out, reducing the false alarm rate and making the detection of external manhole covers more accurate and reliable. Attached Figure Description

[0028] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.

[0029] Figure 1 This is a schematic diagram of the external structure of the manhole cover detection switch provided by this utility model;

[0030] Figure 2 This is a cross-sectional structural schematic diagram of the manhole cover detection switch provided by this utility model;

[0031] Figure 3 This is a comparative schematic diagram of the original base welding assembly and the new flat plate fixed base in the manhole cover detection switch provided by this utility model;

[0032] Figure 4 This is a comparative schematic diagram of the original and new versions of the switch mounting base in the manhole cover detection switch provided by this utility model.

[0033] Figure 5 This is a comparative schematic diagram of the original ball switch board and the new ball switch board in the manhole cover detection switch provided by this utility model;

[0034] Figure 6 This is a comparative diagram of the installation of the original ball switch and the new ball switch in the manhole cover detection switch provided by this utility model;

[0035] Figure 7 This is a comparative diagram of the installation of the original version of the bend joint and the new version of the flexible hose joint (including cable diagram) in the manhole cover detection switch provided by this utility model.

[0036] Figures 1-2 In the middle: 1. Trigger head, 2. Protective sleeve, 3. Fixing sleeve, 4. Fixing base, 5. Pipe cap, 6. Hose connector, 7. Cable, 8. Well cover, 9. Filter circuit board, 10. Switch fixing seat, 11. Ball switch, 12. Reset spring, 13. Cable sleeve, 14. Communication line, 15. Waterproof connector.

[0037] Figures 4-7 In the middle: 100 limiting structure, 101 opening, 102 limiting foot, 111 limiting hole. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0040] Terminology Explanation:

[0041] A tilt ball switch is a mechanical switch that uses the movement of a metal ball to connect or disconnect a circuit. It is commonly used to detect tilt, vibration, or changes in position. In the prior art CN221259907U, when the cover of a cable well is maliciously damaged (such as by unauthorized prying), the cover tilts, triggering the tilt ball switch to send a signal.

[0042] Due to the lack of an effective limiting structure, existing technologies make ball switches prone to misalignment or tilting during installation, resulting in deviations in the trigger angle and affecting detection accuracy. Furthermore, the fixed base adopts a closed structure, making it difficult for the adhesive to fully flow into the cavity at the bottom of the metal trigger head during subsequent potting and sealing, resulting in poor sealing and easy intrusion of moisture into the interior.

[0043] To address this issue, this solution incorporates a limit switch and an interference fit between the switch mounting base and the ball switch to ensure that the ball switch is installed horizontally without deviation. Furthermore, the switch mounting base is designed to be open, making it easier for the sealing adhesive to flow into the bottom cavity of the trigger metal head, thus achieving a better sealing effect.

[0044] In existing technology, communication cables are connected to the detection switch via a 90° bend. Due to limitations in thread length and depth, the cable can only be fixed along the direction of the bend joint. When installed on the manhole cover, this can easily lead to cable redundancy and tangling, restricting the cable's freedom of movement before entering the detection switch. Consequently, the cable entry point is prone to wear and tear, resulting in signal transmission interruption.

[0045] To address this issue, the existing bent pipe structure was eliminated and replaced with a flexible hose connector and cap, which does not restrict the cable's freedom of movement before entering the detection switch. Kevlar aramid high-temperature cable sleeves were also added to the cable, improving its abrasion resistance and cut resistance.

[0046] In addition, the original fixed base that needed to be welded into components has been replaced with a flat fixed base, which reduces complex processing such as welding and threading, making the processing simpler, the cycle shorter, the cost lower, and the installation more convenient.

[0047] Furthermore, by adding a filter circuit board, noise generated by the vibration of the cast iron manhole cover is filtered out, reducing the false alarm rate and making the detection of cast iron manhole covers more accurate and reliable.

[0048] This solution is proposed based on the above improvements, such as... Figures 1-2 As shown, a manhole cover detection switch includes a vertically arranged trigger component, the bottom of which is connected to the manhole cover 8 via a fixed base 4.

[0049] The triggering component includes a communication line 14, a cable sleeve 13, a reset spring 12, and a protective sleeve 2, which are connected sequentially from the inside out.

[0050] One end of the communication line 14 is connected to the ball switch 11, and the other end is connected to the cable 7 through the filter circuit board 9.

[0051] The cable sleeve 13 is fitted on the outside of the communication line 14. The cable sleeve 13 is made of Kevlar aramid high temperature cable sleeve to protect the communication line 14 from wear, cutting or other damage caused by the repeatedly operated return spring 12.

[0052] The return spring 12 is sleeved on the outside of the cable sleeve 13, with one end abutting against the bottom surface of the trigger head 1 and the other end abutting against the upper surface of the fixed base 4, and is used to absorb multi-directional vibration loads from the manhole cover 8. The material of the return spring 12 has been changed from stainless steel 301 to 65Mn special spring steel with nickel plating, which improves the bending fatigue yield strength and the corrosion resistance.

[0053] The protective sleeve 2 is fitted on the outside of the cable sleeve 13. It is made of silicone. After the trigger head 1 is connected to the top, the inside forms a space to accommodate the ball switch 11. After the bottom end of the protective sleeve 2 passes through the fixing sleeve 3, it is connected to the fixing base 4 through the waterproof connector 15.

[0054] The reset spring 12 enables the trigger head 1 to be triggered by impact in any direction, thereby generating a trigger signal for the ball switch 11. After triggering, it returns to the vertical state under the action of the reset spring 12. The triggering angle is diverse. Due to the presence of multiple layers of protection, it can prevent external humid gas from entering the area where the ball switch contacts the communication line as much as possible.

[0055] The manhole cover 8 is equipped with a fixed base 4, which is connected to the protective sleeve 2 and the triggering component via a waterproof connector 1. The manhole cover 8 is also equipped with a fixed sleeve 3, which is used to protect the waterproof connector 15. The fixed sleeve 3 can be a rubber threaded sleeve.

[0056] The waterproof connector 15 is connected to the fixed base 4. One end is connected to the protective sleeve 2, and the other end is connected to the pipe cap 5 and the flexible hose connector 6. After passing through the flexible hose connector 6 and the pipe cap 5, the cable 7 is connected to the communication line 14 through the filter circuit board 9.

[0057] Cable 7 is used to transmit power to ball switch 11 via communication line 14 and to transmit signals triggered by ball switch 11.

[0058] The cap 5 can be an external hexagonal internal thread cap. Electronic sealant is injected into the external hexagonal internal thread cap through the through hole of the hose connector 6 to seal the filter circuit board 9.

[0059] like Figure 3 As shown, the fixed base 4 is plate-shaped and has connecting holes for connecting the manhole cover 8 and the waterproof connector 15, and a through hole in the middle to allow the waterproof connector 15 and the trigger assembly to pass through. In contrast, existing technology ( Figure 3 (Left side) Welded components are used. By replacing the welding components with a flat fixed base, complex processing such as welding and thread cutting is reduced, making the processing simpler, the cycle shorter, the cost lower, and the installation more convenient.

[0060] The ball switch 11 is fixed on the switch plate, and the switch plate is connected to the switch mounting base 10, such as... Figure 4 As shown, Figure 4 The left side shows a switch holder with a closed top, while the switch holder 10 of this solution has an opening 101 at the top and at least two sets of limiting feet 102 at the bottom.

[0061] Correspondingly, such as Figure 5 As shown, Figure 5 The left side shows the switch board of the prior art, while the present solution has a limiting hole 111 on the switch board that corresponds to the position of the limiting foot 102.

[0062] When the switch plate is connected to the switch mounting base 10, it forms the following shape: Figure 6 The limiting structure 100 shown on the right.

[0063] By adding a limiting structure 100 and an interference fit between the switch mounting base 10 and the switch plate, the installation level of the ball switch is ensured to be level and not tilted. The switch mounting base 10 is designed to be open, which makes it easier for the sealing colloid to flow to the bottom cavity of the trigger head, thus achieving a better sealing effect.

[0064] like Figure 7 As shown on the left, existing technology uses a 90° bend to restrict the direction of the cable entering the detection switch. This forces the cable to be fixed along the direction of the bend joint, limiting the cable's freedom of movement before entering the detection switch, leading to inconvenient installation and a high risk of signal transmission interruption. This solution... Figure 7 As shown on the right, the bend in the existing technology has been eliminated and replaced with a flexible hose connector 6 and a cap 5, which does not restrict the freedom of the cable before it enters the detection switch.

[0065] The detection switch of this solution can be assembled in the following ways:

[0066] The trigger head 1 is made of metal. The inside of the trigger head 1 is filled with electronic sealing colloid that occupies about 1 / 3 of the inner cavity volume. After the switch plate and the switch fixing seat 10 are installed with an interference fit, the whole is installed into the cavity of the trigger head 1. Electronic sealing colloid is then filled into the cavity of the trigger head a second time. At this time, the colloid can be well integrated with the colloid filled in the first time through the opening 101 of the switch fixing seat 10, so as to achieve a better sealing effect.

[0067] After the electronic sealing colloid has cured, a Kevlar aramid high-temperature cable sleeve is added to the communication line 14 to protect the cable from wear, cuts, etc.

[0068] The large-diameter end of the 65Mn return spring 12 is installed and tightened onto the thread of the trigger head 1. A protective sleeve 2 of the same length as the return spring is then installed onto the return spring 12. Finally, the small-diameter end of the return spring 12, together with the protective sleeve 2, is installed into the waterproof connector 15.

[0069] The filter circuit board 9 is installed inside the waterproof connector 15, and the communication line 14 is connected to the filter circuit board 9. The filter circuit board 9 is connected to the cable 7.

[0070] Install the waterproof connector 15 into the center hole of the fixed base 4, install the pipe cap 5 onto the waterproof connector 15, and then install the hose connector 6 onto the pipe cap 5.

[0071] Electronic sealant is injected into the external hexagonal internal thread tube cap nut 5 through the through hole of the hose connector 6 to seal the filter circuit board 9;

[0072] The fixing base 4 is installed onto the manhole cover 8, and finally the fixing sleeve 3 is installed onto the manhole cover 8.

[0073] To address the issue of ball switches easily shifting or tilting during installation in existing technologies, this solution incorporates a limiting structure between the switch plate and the switch mounting base. Self-positioning is achieved through the fit between the limiting feet and the limiting holes, as well as the interference fit, ensuring that the ball switch remains level during installation to meet operational requirements.

[0074] In existing technologies, the switch holder of a ball switch uses a sealed structure, which makes it difficult for the sealing adhesive to flow into the trigger head cavity, resulting in a poor seal. This solution provides an opening at the top of the switch holder, making it easier for the sealing adhesive to flow into the bottom cavity of the trigger head, thus achieving a better sealing effect.

[0075] In response to the problem in existing technologies where communication cables are connected to the detection switch via a 90° bend, which restricts the cable's freedom of movement, this solution eliminates the bend structure and replaces it with a flexible hose connector and cap. This eliminates the restriction on the cable's freedom of movement before it enters the detection switch, reduces cable winding before entering the switch, and lowers cable redundancy.

[0076] The original fixed base, which required welding into components, was replaced with a flat plate structure, which reduced complex processing such as welding and threading, reduced manufacturing processes and costs, and improved production efficiency.

[0077] Furthermore, by adding a filter circuit board, noise generated by the vibration of the external manhole cover is filtered out, reducing the false alarm rate and making the detection of external manhole covers more accurate and reliable.

[0078] Furthermore, by adding a protective tube to the outside of the communication line, the wear and tear on the communication line caused by the repeated action of the reset spring is reduced.

[0079] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A manhole cover detection switch, characterized by, It includes a vertically arranged trigger assembly, the bottom of which is connected to the manhole cover via a fixed base; the trigger assembly includes a communication line, a cable sleeve, a return spring, and a protective sleeve, which are sequentially connected from the inside to the outside; the top of the protective sleeve is connected to the trigger head, the return spring abuts against the bottom surface of the trigger head and the upper surface of the fixed base, and the ball switch inside the trigger head is connected to the communication line; The ball switch is fixed on the switch plate, which has a limit hole; the upper surface of the switch plate has a switch mounting base, which has an opening at the top and a limit foot at the bottom, with the limit foot corresponding to the position of the limit hole.

2. A manhole cover detection switch as claimed in claim 1, wherein, The manhole cover is equipped with a fixed base, which is connected to a protective sleeve and a triggering component via a waterproof connector.

3. A manhole cover detection switch as described in claim 1, characterized in that, The fixed base is plate-shaped and has connection holes for connecting the manhole cover and the waterproof connector, and a through hole in the middle to allow the waterproof connector and the trigger assembly to pass through.

4. A manhole cover detection switch as described in claim 1, characterized in that, The manhole cover is equipped with a fixing sleeve, which is used to protect the waterproof joint.

5. A manhole cover detection switch as described in claim 1, characterized in that, The top of the protective sleeve is connected to the trigger head, and the inside forms a space to accommodate the ball switch.

6. A manhole cover detection switch as described in claim 1, characterized in that, The bottom end of the protective sleeve passes through the fixing sleeve and is connected to the fixing base through a waterproof connector.

7. A manhole cover detection switch as described in claim 6, characterized in that, The waterproof connector is connected to the fixed base and has a filter circuit board inside. One end is connected to the protective sleeve, and the other end is connected to the pipe cap and hose connector.

8. A manhole cover detection switch as described in claim 7, characterized in that, The hose connector is provided with a hole for potting and sealing, which is used to seal the filter circuit board by potting glue.

9. A manhole cover detection switch as described in claim 1, characterized in that, One end of the communication line is connected to a ball switch, and the other end is connected to a cable via a filter circuit board.

10. A manhole cover detection switch as described in claim 9, characterized in that, The cable passes through a flexible hose connector and a cap, and is connected to the communication line via a filter circuit board.

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