Limit switch with guard
By designing protective devices for the limit switches, the problems of damage caused by external debris intrusion and excessive contact are solved, resulting in a longer service life and greater reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TEVOS (SHANGHAI) IND CO LTD
- Filing Date
- 2025-07-30
- Publication Date
- 2026-07-07
AI Technical Summary
Current limit switches lack protective devices, making them susceptible to damage to internal components due to the intrusion of external debris and excessive contact. Furthermore, the metal contacts are easily damaged by instantaneous high currents, affecting their service life.
A limit switch with protective devices is designed, including a protective shell, a splash-proof shell, a cam and a rotating rod insertion and rotation mechanism, a buffer rubber block, a transparent cover, and a fuse. Through the coordinated use of these components, external debris is prevented from entering, excessive torque is buffered, and internal components are protected.
It improves the protection capability of the limit switch, extends its service life, facilitates the observation and maintenance of internal components, and reduces the risk of damage caused by high current and external force.
Smart Images
Figure CN224472354U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of limit switch technology, specifically a limit switch with a protective device. Background Technology
[0002] Limit switches, also known as travel switches, are small-current master control electrical appliances. They can control the connection and closure of circuits by changing the opening and closing state of the internal contacts of the limit switch through contact with external objects to push the linkage. This enables many functions such as sequential control, positioning control and position status detection, and they are widely used in electrical control systems.
[0003] Existing limit switches are often used as standalone components with almost no protective devices. This results in limited protection against the intrusion of water, oil, dust, and other contaminants during use, significantly affecting the reliability of limit switches in harsh environments. Furthermore, the metal contacts within limit switches cannot prevent instantaneous current overload. When an abnormally large current occurs in the circuit, it can easily damage the contacts or wiring of the limit switch, thus affecting its lifespan. Additionally, during use, the limit switch relies on the pushing action of an object to connect the circuit, which can easily lead to excessive pushing force on the shaft, causing damage to internal components due to excessive force. Utility Model Content
[0004] The purpose of this utility model is to provide a limit switch with a protective device to solve the problems mentioned in the background art, such as the easy intrusion of external debris into the limit switch and the easy damage to the internal parts of the limit switch due to excessive contact.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a limit switch with a protective device, comprising a protective housing, a rotating rod rotatably mounted inside the protective housing, one end of the rotating rod penetrating the outer surface of the protective housing, a splash-proof shell fixedly mounted on one side of the outer surface of the protective housing, the splash-proof shell being circular in design and concentric with the rotating shaft of the rotating rod, a switch body fixedly mounted on the outer surface of the protective housing, and the switch body being fixed to the protective housing using screws, a connecting block fixedly mounted on the outer surface of the protective housing, and a tension spring passing through the outer surface of the connecting block, a connecting pin penetrating the outer surface of the rotating rod and fitting against the outer surface of the rotating rod, the rotating rod being connected to the tension spring, a roller rotatably mounted on one end of the rotating rod outside the protective housing, and a plug-in rotating mechanism being provided between the rotating rod and the switch body.
[0006] Preferably, the plug-in rotation mechanism includes a cam, which is plugged into and mounted on the outer surface of the rotating rod shaft, and the rotating rod shaft and the cam are interference fit. The side surface of the cam is in contact with the outer surface of the switch body. The cam is located inside the splash-proof shell, and a gap is left between the cam and the mounting protective shell.
[0007] By adopting the above technical solution, the connection between the cam and the rotating rod can drive the cam to rotate together after the rotating rod rotates, so that the cam can push the switch body and trigger the connection. By using the fixed length of the cam, the switch body will not be damaged due to excessive force after the rotating rod rotates excessively.
[0008] Preferably, the interior of the mounting protective shell is inclined, and a buffer rubber block is threadedly installed on the outer surface of the mounting protective shell near the connecting block, and the outer surface of the buffer rubber block is in contact with the outer surface of the rotating rod.
[0009] By adopting the above technical solution, the inclined design of the protective shell allows the liquid entering the protective shell to be guided and flow out, preventing the liquid from remaining inside the protective shell. At the same time, the use of buffer rubber blocks prevents the rotating rod from breaking or deforming due to collision with the protective shell when it returns to its original position.
[0010] Preferably, the splash-proof shell has an annular protrusion on the side away from the protective shell, and a shielding cover is snapped onto the outer surface of the protective shell, with a sealing gasket between the shielding cover and the splash-proof shell. The outer surface of the shielding cover is uniformly provided with elastic blocks, which engage with the splash-proof shell.
[0011] By adopting the above technical solution, the shielding cover is fixedly installed on the outer surface of the splash-proof shell by the elastic clip, so that the splash-proof shell and the shielding cover can block the external liquid, so that the switch body will not come into contact with the liquid and be damaged, thus providing protection for the switch body.
[0012] Preferably, the cover is made of transparent material, and a mounting block is fixedly installed on the outer surface of one end of the cover. An LED component is engaged inside the mounting block, and both ends of the LED component are connected to the pins of the switch body. A lens is fixedly installed on the outer surface of one end of the cover, and the lens, the mounting block, and the LED component are concentrically designed.
[0013] By adopting the above technical solution, the transparent design of the cover allows users to directly see the components inside the splash-proof shell, while the mounting and positioning block can install and fix the LED components, and the lens makes the light emitted by the LED components more conspicuous, allowing users to judge the usage status of the limit switch through the LED components and to determine whether the switch body is damaged.
[0014] Preferably, a wiring plug is fitted onto the outer surface of the splash-proof shell, and a cable passes through the outer surface of the wiring plug. The outer surface of the wiring plug is in close contact with the outer surface of the protective shell, and the outer surface of the wiring plug is engaged with the outer surface of the shield. The wiring plug and the splash-proof shell are designed at an angle.
[0015] Using the above technical solution, the cable passing through can be protected by the connector plug. At the same time, the inclined design of the connector plug can further reduce the chance of liquid entering the splash-proof housing and facilitate installation.
[0016] Preferably, a plug slot is fixedly installed at one end inside the shielding cover, and a fuse is plugged into the outer surface of the plug slot. A fuse base is fixedly installed at one end inside the splash-proof shell, and the fuse base is plugged into the fuse. One end of the fuse base is connected to the switch body, and the other end of the fuse base is connected to the LED assembly.
[0017] By adopting the above technical solution, the fuse can be installed inside the shielding cover through the plug slot. After the shielding cover is fixedly installed on the outer surface of the splash-proof shell, the fuse can be installed and plugged into the fuse base at the same time. This facilitates the installation of the fuse while protecting the switch body and circuit inside the splash-proof shell from damage caused by abnormally large currents.
[0018] Compared with the prior art, the beneficial effects of this utility model are: the limit switch with a protective device:
[0019] 1. When the protective housing is installed and fixed in use, the rotating rod will be pushed and drive the cam to rotate synchronously. The fixed gap between the cam and the switch body prevents the rotating rod from being damaged after excessive rotation. Then, the elasticity and tension of the tension spring will allow the rotating rod to automatically return to its original position. This prevents the rotating rod, cam and switch body from being damaged due to excessive thrust when the rotating rod is over-rotated, thus extending the service life of the limit switch.
[0020] 2. The transparent material of the cover allows easy viewing of the wiring and components inside the splash-proof housing. The mounting and positioning block can install and fix the LED components, so that the LED components can light up synchronously after the switch body is triggered. The brightness of the LED components is enhanced by the lens, and the operating status of the limit switch can be judged by the lighting of the LED components. The condition of the switch body can also be judged by the LED components.
[0021] 3. The flexible locking block allows for easy and secure installation of the shielding cover on the outer surface of the splash-proof housing, while the insertion slot secures the fuse to one side of the shielding cover. After the shielding cover is installed on the outer surface of the splash-proof housing, the fuse can be simultaneously inserted into the fuse base, enabling the fuse to protect the components and wiring inside the splash-proof housing and reduce damage to components and wiring caused by excessive instantaneous current. Attached Figure Description
[0022] Figure 1 This is a three-dimensional structural diagram of the protective shell and lens of this utility model;
[0023] Figure 2 This is a three-dimensional cross-sectional view of the protective shell and rotating rod of this utility model.
[0024] Figure 3 This is a three-dimensional schematic diagram of the explosive structure of the tension spring and buffer rubber block of this utility model;
[0025] Figure 4 This is a cross-sectional perspective view of the shielding cover and the mounting positioning block of this utility model.
[0026] Figure 5 This is a three-dimensional structural diagram of the cam and switch body of this utility model;
[0027] Figure 6 This is a three-dimensional structural diagram of the LED component and the insertion slot of this utility model.
[0028] In the diagram: 1. Protective housing; 2. Rotating rod; 3. Connecting pin; 4. Connecting block; 5. Tension spring; 6. Buffer rubber block; 7. Splash-proof housing; 8. Cam; 9. Switch body; 10. Cover; 11. Mounting positioning block; 12. LED assembly; 13. Lens; 14. Elastic locking block; 15. Wiring plug; 16. Fuse base; 17. Fuse; 18. Plug slot. Detailed Implementation
[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0030] Please see Figure 1-6This utility model provides a technical solution: a limit switch with a protective device, including a protective housing 1, a rotating rod 2 rotatably mounted inside the protective housing 1, one end of the rotating rod 2 penetrating the outer surface of the protective housing 1, a splash-proof shell 7 fixedly mounted on one side of the outer surface of the protective housing 1, the splash-proof shell 7 being circular in design, and the rotating shaft of the splash-proof shell 7 and the rotating rod 2 being concentrically designed, a switch body 9 fixedly mounted on the outer surface of the protective housing 1, and the switch body 9 being fixed to the protective housing 1 by screws, a connecting block 4 fixedly mounted on the outer surface of the protective housing 1, and a tension spring 5 passing through the outer surface of the connecting block 4, a connecting nail 3 penetrating the outer surface of the rotating rod 2, and the connecting nail 3 being in contact with the outer surface of the rotating rod 2, the rotating rod 2 being connected to the tension spring 5, a roller rotatably mounted on one end of the rotating rod 2 located outside the protective housing 1, and a plug-in rotating mechanism being provided between the rotating rod 2 and the switch body 9.
[0031] After the protective shell 1 is fixed in the installation position, the rotating rod 2 will rotate due to the push of the moving parts. The roller at one end of the rotating rod 2 can reduce the friction. The connecting pin 3 and the connecting block 4 are connected by the tension spring 5, so that the tension spring 5 can automatically reset the rotating rod 2 through its own elastic tension.
[0032] The plug-in rotation mechanism includes a cam 8, which is plugged into the outer surface of the rotating shaft of the rotating rod 2. The rotating shaft of the rotating rod 2 and the cam 8 are interference fit. The side surface of the cam 8 is in contact with the outer surface of the switch body 9. The cam 8 is located inside the splash-proof shell 7. There is a gap between the cam 8 and the mounting protective shell 1.
[0033] The interference fit between the cam 8 and the rotating rod 2 allows the cam 8 to be firmly fixed on the outer surface of the rotating rod 2. The cam 8 can be replaced when it is damaged. The use of the cam 8 keeps the distance between the rotating shaft of the rotating rod 2 and the switch body 9 constant, so that the switch body 9 will not be squeezed and damaged due to the rotation of the cam 8 after the rotating rod 2 rotates excessively.
[0034] The interior of the protective housing 1 is designed to be inclined. A buffer rubber block 6 is threadedly installed on the outer surface of the protective housing 1 near the connecting block 4, and the outer surface of the buffer rubber block 6 is in contact with the outer surface of the rotating rod 2.
[0035] The inclined design of the protective shell 1 allows liquid to flow out along the inclined surface after entering the temporal part of the protective shell 1, preventing liquid from accumulating inside the protective shell 1. At the same time, the use of the buffer rubber block 6 can buffer the reset rotating rod 2, preventing the rotating rod 2 from being damaged or deformed due to impact. The buffer rubber block 6 can also be replaced if it is damaged.
[0036] The splash-proof shell 7 has an annular protrusion on the side away from the protective shell 1, and a shield 10 is snapped onto the outer surface of the protective shell 1. A sealing gasket is provided between the shield 10 and the splash-proof shell 7. Elastic blocks 14 are evenly distributed on the outer surface of the shield 10, and the elastic blocks 14 engage with the splash-proof shell 7.
[0037] The annular protrusion of the splash-proof housing 7 can further reduce the chance of liquid entering the splash-proof housing 7, while the shielding cover 10 can be quickly fixed to the outer surface of the splash-proof housing 7 by the elastic locking block 14, so that the splash-proof housing 7 and the shielding cover 10 can protect the internal components and reduce the chance of damage caused by liquid ingress into the switch body 9.
[0038] The cover 10 is made of transparent material, and a mounting block 11 is fixedly installed on the outer surface of one end of the cover 10. An LED component 12 is installed inside the mounting block 11, and the two ends of the LED component 12 are respectively connected to the pins of the switch body 9. A lens 13 is fixedly installed on the outer surface of one end of the cover 10, and the lens 13, the mounting block 11 and the LED component 12 are concentrically designed.
[0039] The transparent material of the cover 10 allows users to observe the use and operation of the internal components of the splash-proof shell 7. The LED component 12 can be installed and fixed by the use of the mounting positioning block 11, so that the LED component 12 can light up after the switch body 9 is triggered. The lens 13 enhances the light-emitting effect of the LED component 12, allowing users to know the operation of the limit switch by using the LED component 12.
[0040] The outer surface of the splash-proof shell 7 is fitted with a wiring plug 15, and the outer surface of the wiring plug 15 is through which the cable passes. The outer surface of the wiring plug 15 is in close contact with the outer surface of the protective shell 1. The outer surface of the wiring plug 15 is engaged with the outer surface of the shield 10. The wiring plug 15 and the splash-proof shell 7 are designed at an angle.
[0041] The wiring plug 15 can protect the wiring that penetrates the splash-proof housing 7. The inclined design of the wiring plug 15 can further reduce the chance of liquid entering the splash-proof housing 7 and facilitate the installation and fixation of the wiring plug 15.
[0042] A plug slot 18 is fixedly installed inside one end of the shield 10, and a fuse 17 is plugged into the outer surface of the plug slot 18. A fuse base 16 is fixedly installed inside one end of the splash-proof shell 7, and the fuse base 16 is plugged into the fuse 17. One end of the fuse base 16 is connected to the switch body 9, and the other end of the fuse base 16 is connected to the LED assembly 12.
[0043] The fuse 17 can be installed inside the cover 10 through the insertion slot 18. After the cover 10 is installed on the outer surface of the splash-proof shell 7, the fuse 17 can be inserted into the fuse base 16. This allows the fuse base 16 and the fuse 17 to be connected at the same time as the cover 10 is installed. The fuse 17 can also protect the components and circuits of the limit switch, preventing damage to the components and circuits due to instantaneous high current.
[0044] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A limit switch with a protective device, comprising a protective housing (1), wherein a rotating rod (2) is rotatably mounted inside the protective housing (1), and one end of the rotating rod (2) penetrates the outer surface of the protective housing (1); a splash-proof shell (7) is fixedly mounted on one side of the outer surface of the protective housing (1), and the splash-proof shell (7) is circular in design, and the rotating shaft of the splash-proof shell (7) and the rotating rod (2) are concentrically designed; a switch body (9) is fixedly mounted on the outer surface of the protective housing (1), and the switch body (9) is fixed to the protective housing (1) by screws, characterized in that: A connecting block (4) is fixedly installed on the outer surface of the mounting protective shell (1), and a tension spring (5) passes through the outer surface of the connecting block (4). A connecting nail (3) is installed through the outer surface of the rotating rod (2), and the connecting nail (3) is in contact with the outer surface of the rotating rod (2). The rotating rod (2) is connected to the tension spring (5). A roller is rotatably installed at one end of the rotating rod (2) located outside the mounting protective shell (1). A plug-in rotating mechanism is provided between the rotating rod (2) and the switch body (9).
2. A limit switch with a protective device according to claim 1, characterized in that: The plug-in rotating mechanism includes a cam (8), which is plugged into the outer surface of the rotating shaft of the rotating rod (2), and the rotating shaft of the rotating rod (2) and the cam (8) are interference fit. The side surface of the cam (8) is in contact with the outer surface of the switch body (9). The cam (8) is located inside the splash-proof shell (7), and there is a gap between the cam (8) and the mounting protective shell (1).
3. A limit switch with a protective device according to claim 1, characterized in that: The interior of the mounting protective shell (1) is inclined. A buffer rubber block (6) is threaded on the outer surface of the mounting protective shell (1) near the connecting block (4), and the outer surface of the buffer rubber block (6) is in contact with the outer surface of the rotating rod (2).
4. A limit switch with a protective device according to claim 1, characterized in that: The splash-proof shell (7) has an annular protrusion on the side away from the protective shell (1), and a shield (10) is snapped onto the outer surface of the protective shell (1). A sealing gasket is provided between the shield (10) and the splash-proof shell (7). Elastic blocks (14) are evenly provided on the outer surface of the shield (10), and the elastic blocks (14) engage with the splash-proof shell (7).
5. A limit switch with a protective device according to claim 4, characterized in that: The cover (10) is made of transparent material, and a mounting block (11) is fixedly installed on the outer surface of one end of the cover (10). An LED component (12) is installed inside the mounting block (11), and the two ends of the LED component (12) are respectively connected to the pins of the switch body (9). A lens (13) is fixedly installed on the outer surface of one end of the cover (10), and the lens (13), the mounting block (11) and the LED component (12) are concentrically designed.
6. A limit switch with a protective device according to claim 1, characterized in that: The outer surface of the splash-proof shell (7) is fitted with a wiring plug (15), and the outer surface of the wiring plug (15) is through which a cable passes. The outer surface of the wiring plug (15) is in close contact with the outer surface of the protective shell (1), and the outer surface of the wiring plug (15) is engaged with the outer surface of the shield (10). The wiring plug (15) and the splash-proof shell (7) are designed to be inclined.
7. A limit switch with a protective device according to claim 4, characterized in that: The shield (10) has a fixed insertion slot (18) at one end inside, and a fuse (17) is inserted into the outer surface of the insertion slot (18). The splash-proof shell (7) has a fixed fuse base (16) at one end inside, and the fuse base (16) is inserted into the fuse (17). One end of the fuse base (16) is connected to the switch body (9), and one end of the fuse base (16) is connected to the LED assembly (12).