A portable alternating current charging gun

Abstract

The utility model discloses a portable alternating current charging gun belongs to electric automobile charging gun technical field. It mainly includes charging gun body, and the outside of charging gun body is equipped with charging gun shell, and the front end sealing fixed connection of charging gun shell has the gun head, and the inside of gun head is equipped with L1 alternating current power terminal, the gun head includes the fixed seat and the mounting seat of one body forming, and the position of mounting seat is close to L1 alternating current power terminal and is equipped with the mounting hole, and the fixed seat is equipped with inductive groove no.

Description

Technical Field

[0001] This utility model belongs to the field of electric vehicle charging gun technology, and more specifically, it relates to a portable AC charging gun. Background Technology

[0002] With increasing global attention to environmental protection and sustainable development, electric vehicles, as a clean energy mode of transportation, are becoming increasingly popular. To meet the charging needs of electric vehicles, AC charging guns, as one of the key charging devices, are widely used.

[0003] Currently, there are two common types of charging guns. One type has an on-cable control box, such as the multi-functional portable AC charging gun disclosed in patent publication number "CN205646894U". Its casing contains a charging gun control circuit, which includes a power module, voltage detection module, leakage and overcurrent detection module, CP signal generation module, CP signal detection module, indicator module, display module, switch control module, central processing unit, and wireless Bluetooth module. This charging gun can be carried and used in electric vehicles for convenient charging. However, it lacks plug temperature protection and nozzle temperature protection, posing a significant safety hazard. Outdoor use carries the risk of electric shock and potential fire from overheated plugs and nozzles.

[0004] Another type is the integrated charging gun. For example, patent publication number "CN115626074A" discloses a portable AC charging gun. This design divides the existing charging control circuit into four circuit boards, which are then connected by wires and installed inside the gun body. This reduces the size of the charging control box and integrates it with the charging gun. However, this AC charging gun lacks head temperature protection and leakage protection functions. Furthermore, the plug only has one temperature sensor between the neutral and live wires, resulting in incomplete temperature monitoring and a potential fire hazard due to overheating. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a portable AC charging gun that can quickly and accurately detect the temperature of the plug and the gun head and control the temperature. At the same time, it can safely and conveniently detect leakage in the circuit and automatically disconnect the power supply when leakage occurs to protect the safety of the user and the vehicle.

[0006] The portable AC charging gun includes a charging gun body, a charging gun shell on the outside of the charging gun body, a gun head sealed and fixedly connected to the front end of the charging gun shell, and an L1 AC power terminal inside the gun head; the gun head includes an integrally formed fixing base and a mounting base, a mounting hole is opened on the mounting base near the L1 AC power terminal, a sensing groove is opened on the fixing base around the L1 AC power terminal, the sensing groove is connected to the mounting hole, an L1 temperature sensor is installed in the mounting hole, the probe surface of the L1 temperature sensor is coated with insulating varnish, and the probe of the L1 temperature sensor extends into the sensing groove and is close to or directly abutting the L1 AC power terminal.

[0007] Preferably, the mounting hole is provided with a limiting and fixing mechanism for fixing the L1 temperature sensor. The limiting and fixing mechanism includes an insulating limiting tube, which is interference-fitted with the mounting hole. Multiple evenly distributed insulating flexible baffles are fixedly connected to the inner wall of the insulating limiting tube.

[0008] Preferably, one end of the insulating limiting tube extends into the first sensing groove and is fixedly connected to the first sensing groove, and the second sensing groove is provided on the side of the insulating limiting tube near the L1 AC power terminal.

[0009] Preferably, the charging gun housing contains a circuit board, on which a control module is mounted, and the wires of the L1 temperature sensor are connected to the control module.

[0010] Preferably, it also includes a charging plug and a protector, with the two ends of the protector connected to the charging gun body and the charging plug respectively via cables.

[0011] Preferably, the charging plug is provided with a second grounding terminal, a second N-line terminal, an L-line terminal, an L-line temperature sensor, and an N-line temperature sensor. The probe surfaces of the L-line temperature sensor and the N-line temperature sensor are coated with insulating varnish. The L-line temperature sensor is matched with the L-line terminal, and the N-line temperature sensor is matched with the second N-line terminal.

[0012] Preferably, the protector includes a temperature sensor, a leakage current sensor, a current transformer, and a power failure protection device. The N-line temperature sensor and the L-line temperature sensor are connected to the temperature sensor. The charging circuit of the charging gun body is connected to the current transformer. The current transformer is connected to the leakage current sensor. The temperature sensor, the leakage current sensor, the charging plug, and the charging gun body are all connected to the power failure protection device.

[0013] Compared with the prior art, the beneficial effects of this utility model are: 1. An L1 temperature sensor is added inside the gun head. The L1 temperature sensor monitors the temperature of the L1 AC power terminal at close range through the sensing slot. L-line and N-line temperature sensors are added inside the charging plug to monitor the temperature of the corresponding terminals respectively. This realizes full-link temperature monitoring from the gun head to the plug. When the temperature is abnormal, it can be adjusted by stepping down the voltage at the CP terminal in conjunction with the control module, or the power-off protection device of the protector can be triggered to cut off the circuit, thus avoiding the risk of fire caused by overheating of the terminals from the source.

[0014] 2. All sensor probes are coated with insulating varnish. The insulating varnish serves as insulation and isolation, preventing the probe from directly contacting the conductive terminals and causing a short circuit. At the same time, it allows the probe to be closer to the terminals without affecting heat conduction.

[0015] 3. An additional limiting and fixing mechanism is added to the L1 temperature sensor. The limiting and fixing mechanism prevents the L1 temperature sensor from being displaced or falling off due to external forces such as vibration or insertion and removal during use, ensuring the stability of temperature monitoring. Furthermore, the insulation design of the insulating limiting tube and flexible baffle completely eliminates the risk of short circuit and ensures electrical safety.

[0016] 4. The protector integrates a leakage current collector and a current transformer, enabling real-time monitoring of circuit leakage and terminal overheating. Together with the grounding terminal, it forms a double leakage protection to prevent electric shock to users and greatly improve charging safety. It is suitable for inputting 220V AC power into electric vehicle charging devices. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 A schematic diagram of the charging gun body; Figure 3 This is a schematic diagram of the internal structure of the gun head; Figure 4 This is a schematic diagram of the disassembled structure of the gun head; Figure 5 This is a schematic diagram of the structure of induction slot one; Figure 6 This is a schematic diagram of the limiting and fixing mechanism; Figure 7 A schematic diagram of the disassembled structure of the charging plug; Figure 8 This is a schematic diagram of the electrical connections of this utility model; Figure 9 This is the circuit schematic diagram of this utility model.

[0018] In the diagram, 1. Charging gun body; 11. Charging gun shell; 12. Gun head; 121. Fixing base; 1211. Sensing slot one; 122. Mounting base; 1221. Mounting hole; 124. L1 temperature sensor; 125. Limiting and fixing mechanism; 1251. Insulating limiting tube; 1252. Insulating flexible baffle; 1253. Sensing slot two; 13. Power metal terminal; 131. L1 AC power terminal; 132. N-line terminal one; 133. Grounding terminal one; 14. Signal... 1. Metal terminal; 141. CC charging connection terminal; 142. Charging connection confirmation terminal; 15. Mechanical lock; 16. Button; 17. Circuit board; 2. Protector; 201. Temperature sensor; 202. Leakage current sensor; 203. Current transformer; 204. Power failure protection device; 3. Charging plug; 301. Grounding terminal two; 302. L-line terminal; 303. N-line terminal two; 304. L-line temperature sensor; 305. N-line temperature sensor; 4. Cable. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings: The directional terms used in the detailed description paragraphs are only for the convenience of those skilled in the art to understand the technical solutions described in this application based on the visual orientation shown in the accompanying drawings. Unless otherwise expressly specified and limited, the terms "setting," "installation," "connection," etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0020] Example 1: like Figures 1 to 6 As shown, a portable AC charging gun includes a charging gun body 1, with a charging gun shell 11 on the outside of the charging gun body 1. The charging gun shell 11 protects the internal components, isolating them from external dust, moisture, and mechanical impact. A gun head 12 is sealed and fixedly connected to the front end of the charging gun shell 11. The gun head 12 is used to connect to a car charging terminal for charging. Specifically, the gun head 12 has a power metal terminal 13 and a signal metal terminal 14. The power metal terminal 13 is responsible for conducting AC power from the charging gun to the vehicle battery, and the signal metal terminal 14 is responsible for signal interaction during the charging process, establishing a communication connection between the charging gun and the vehicle to ensure that both parties cooperate to complete the charging process. The power supply metal terminal 13 includes a grounding terminal 133, a neutral (N) terminal 132, and an L1 AC power terminal 131. The grounding terminal 133 is connected to the vehicle's grounding terminal to form a protective grounding circuit. When a leakage fault occurs in the charging gun or vehicle, the leakage current can be conducted to the ground to prevent electric shock to the user or damage to the equipment. The neutral (N) terminal 132 serves as the return terminal for the AC power supply and, together with the L1 AC power terminal 131 (live wire terminal), forms a complete power supply circuit to ensure normal current flow. The signal metal terminal 14 includes a CC charging connection terminal 141 and a charging connection confirmation terminal 142. The CC charging connection terminal 141 is used to detect the physical connection status between the charging gun and the vehicle charging interface. It determines whether the gun head is fully inserted and locked by the change of resistance signal, so as to prevent accidental charging when the connection is not reliable. The charging connection confirmation terminal 142 (CP terminal) is used to monitor abnormal status during the charging process and realize real-time communication between the charging gun and the vehicle OBC.

[0021] The nozzle 12 includes an integrally formed fixed base 121 and mounting base 122. A mounting hole 1221 is provided on the mounting base 122 near the L1 AC power terminal 131, providing mounting space for the L1 temperature sensor 124 and ensuring the sensor's position is fixed. A sensing groove 1211 is formed around the L1 AC power terminal 131, allowing the sensor probe to be close to the L1 AC power terminal 131, improving the sensitivity of temperature monitoring. The sensing groove 1211 communicates with the mounting hole 1221, which houses the L1 temperature sensor 124. The probe surface of the L1 temperature sensor 124 is coated with insulating varnish, which prevents direct contact between the probe and the conductive terminal, thus avoiding short circuits, and does not affect heat conduction. The probe of the L1 temperature sensor 124 extends into the sensing slot 1211 and cooperates with the L1 AC power terminal 131. During installation, the probe and the L1 AC power terminal 131 can be set close to each other or directly against each other, so as to realize real-time monitoring of the terminal's operating temperature and prevent overheating risk.

[0022] The mounting hole 1221 is equipped with a limiting and fixing mechanism 125 for fixing the L1 temperature sensor 124. The limiting and fixing mechanism 125 is used to prevent the L1 temperature sensor 124 from shifting or falling off during use due to external forces such as vibration or insertion / removal, thus ensuring the stability of temperature monitoring. Specifically, as... Figure 6 As shown, the limiting and fixing mechanism 125 includes an insulating limiting tube 1251. The insulating limiting tube 1251 is made of insulating material to avoid forming a conductive path with the sensor or terminal. The insulating limiting tube 1251 is interference-fitted with the mounting hole 1221. Multiple evenly distributed insulating flexible baffles 1252 are fixedly connected to the inner wall of the insulating limiting tube 1251. The insulating flexible baffles 1252 not only ensure that the probe of the L1 temperature sensor 124 is stably limited, but also form an auxiliary clamp for the sensor's wires, while maintaining the insulation characteristics.

[0023] The first sensing slot 1211 preferably has a teardrop-shaped structure. During installation, one end of the insulating limiting tube 1251 extends into the first sensing slot 1211 and is fixed to the small arc end of the first sensing slot 1211. This can further enhance the connection strength of the overall structure and prevent the limiting and fixing mechanism 125 from loosening. The second sensing slot 1253 is provided on the side of the insulating limiting tube 1251 near the L1 AC power terminal 131. The second sensing slot 1253 provides the probe of the L1 temperature sensor 124 with space closer to the L1 AC power terminal 131, reducing the heat conduction path and improving the response speed and accuracy of temperature monitoring.

[0024] The charging gun housing 11 has a mechanical lock 15 at its front end. The mechanical lock 15 is a hook structure that locks the charging gun after it is connected to the vehicle interface, preventing the gun head from falling off due to accidental collisions or dragging during charging, thus ensuring continuous and safe charging. The charging gun housing 11 also has a button 16 for controlling the mechanical lock 15. The button 16 is preferably a spring button. In use, the button 16 connects to the hook of the mechanical lock 15 via an internal connecting rod. When the button 16 is pressed, the connecting rod pushes the hook away from the locking slot of the vehicle interface, unlocking the charging gun. After releasing, the spring returns to its original position, and the hook returns to its ready position, allowing the user to unlock and remove the charging gun after charging is complete. The mechanical lock 15 and button 16 are existing technologies and will not be described in detail. The charging gun housing 11 contains a circuit board 17, which houses a control module. The wires of the L1 temperature sensor 124 are connected to the control module. Circuit board 17 provides a mounting carrier for the control module. The control module, as the core control unit, is commercially available. The principle is described in CN205646894U. It can receive the temperature signal transmitted by L1 temperature sensor 124 and adjust the PWM duty cycle of the CP terminal according to the temperature signal, thereby adjusting the magnitude of the output current.

[0025] Example 2: like Figures 7 to 9 As shown, it also includes a charging plug 3 and a protector 2. The protector 2 is connected to the charging gun body 1 and the charging plug 3 respectively via cables 4 at both ends. The charging plug 3 is used to connect to the mains power interface to introduce external power; the protector 2 has the function of safety monitoring and protection during charging. During manufacturing, the surface of the protector 3 is covered with a protective film to increase its protection level and make the product safer to use.

[0026] The charging plug 3 contains a grounding terminal 301, a neutral (N) terminal 303, a live (L) terminal 302, an L-line temperature sensor 304, and a neutral (N) temperature sensor 305. Grounding terminal 301, N-line terminal 303, and L-line terminal 302 are existing technologies. The neutral (N) terminal 303 and the live (L) terminal 302 transmit the neutral and live currents of the AC power supply, respectively, forming a power supply circuit. The probe surfaces of both the L-line temperature sensor 304 and the N-line temperature sensor 305 are coated with insulating varnish to prevent short circuits between the sensors and terminals. The L-line temperature sensor 304 works in conjunction with the L-line terminal 302, and the N-line temperature sensor 305 works in conjunction with the neutral (N) terminal 303. The L-line temperature sensor 304 and the N-line temperature sensor 305 detect the corresponding L-line terminal 302 and N-line terminal 303, enabling temperature monitoring of key conductive parts of the charging plug 3 and preventing overheating and malfunctions.

[0027] like Figure 8 As shown, the protector 2 is equipped with a temperature sensor 201, a leakage current sensor 202, a current transformer 203, and a power failure protection device 204. The N-line temperature sensor 305 and the L-line temperature sensor 304 are connected to the temperature acquisition unit 201. The temperature acquisition unit 201 receives signals from the L-line temperature sensor 304 and the N-line temperature sensor 305, processes them centrally, and determines whether the temperature is abnormal. The charging circuit of the charging gun body 1 is connected to the current transformer 203. The current transformer 203 detects current changes in the charging circuit, providing data for leakage monitoring. The current transformer 203 is connected to the leakage current acquisition unit 202. The leakage current acquisition unit 202 determines whether there is a leakage phenomenon based on the signal from the current transformer 203. The temperature acquisition unit 201, the leakage current acquisition unit 202, the charging plug 3, and the charging circuit of the charging gun body 1 are all connected to the power-off protection device 204. The power-off protection device 204 acts as an actuator. When the temperature acquisition unit 201 detects over-temperature, the leakage current acquisition unit 202 detects leakage, or other safety abnormalities occur in the charging plug 3 or the charging gun body 1, it immediately cuts off the charging circuit and stops the power supply, preventing safety accidents from the source and achieving multiple safety protections for the entire charging system. It should be noted that the temperature acquisition device 201, leakage current acquisition device 202, current transformer 203 and power failure protection device 204 are all existing technologies and are available on the market.

[0028] Working principle: like Figure 9As shown, during charging, when the charging head 12 is inserted into the vehicle interface, the mechanical lock 15 automatically locks, and the button 16 is in the locked state, ensuring that the charging head will not accidentally fall off during the charging process. The CC charging connection terminal 141 detects the physical connection in place through the change of resistance signal and transmits the signal to the control module. The charging connection confirmation terminal 142 (CP terminal) establishes communication with the vehicle's OBC and interacts through PWM signals, and the vehicle sends a charging permission command.

[0029] After receiving the vehicle's charging permission signal, the control module closes the main circuit through the power-off protection device 204 of the protector 2. The mains power sequentially passes through the L-line terminal 302 and N-line terminal 303 of the charging plug 3, the protector 2, the AC power terminal of the charging gun body 1, and the vehicle's charging interface, forming a three-phase or single-phase AC power supply circuit. Grounding terminal 133 and grounding terminal 301 form a complete grounding protection, connecting the equipment's metal casing to the earth to prevent leakage risks.

[0030] During charging, the L1 temperature sensor 124 inside the charging head 12 monitors the temperature of the power terminal in real time. The L1 temperature sensor 124 feeds the temperature signal back to the charging head control module, which can control the PWM duty cycle of the CP terminal. The L-line temperature sensor 304 and the N-line temperature sensor 305 monitor the temperature of the charging plug terminals. The terminal temperature signals are collected and analyzed by the temperature acquisition unit 201. The current transformer 203 detects the main circuit current, and the leakage current acquisition unit 202 compares the difference between the current of the live wire and the neutral wire. When the difference exceeds 30mA, it is determined to be a leakage current. If the temperature acquisition unit 201 detects that the temperature of any terminal exceeds the safety threshold, or the leakage current acquisition unit 202 detects a leakage current, or the vehicle OBC sends a stop charging signal, the control module immediately triggers the power-off protection device 204 to cut off the main circuit, ensuring the safe charging of the electric vehicle. When the temperature of the L-line terminal 302 and the N-line terminal 303 of the power plug 3 is lower than the limited safety threshold, the power-off protection device 204 can close the power supply to continue charging.

[0031] Finally, although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A portable AC charging gun, comprising a charging gun body (1), a charging gun shell (11) on the outside of the charging gun body (1), a gun head (12) sealed and fixedly connected to the front end of the charging gun shell (11), and an L1 AC power terminal (131) provided inside the gun head (12); characterized in that: The gun head (12) includes an integrally formed fixed base (121) and mounting base (122). The mounting base (122) has a mounting hole (1221) near the L1 AC power terminal (131). The fixed base (121) has a sensing groove (1211) around the L1 AC power terminal (131). The sensing groove (1211) is connected to the mounting hole (1221). The mounting hole (1221) is equipped with an L1 temperature sensor (124). The probe surface of the L1 temperature sensor (124) is coated with insulating varnish, and the probe of the L1 temperature sensor (124) extends into the sensing groove (1211) and is close to or directly abuts against the L1 AC power terminal (131).

2. The portable AC charging gun according to claim 1, characterized in that: The mounting hole (1221) is provided with a limiting and fixing mechanism (125) for fixing the L1 temperature sensor (124). The limiting and fixing mechanism (125) includes an insulating limiting tube (1251). The insulating limiting tube (1251) is interference-fitted with the mounting hole (1221). Multiple evenly distributed insulating flexible baffles (1252) are fixedly connected to the inner wall of the insulating limiting tube (1251).

3. A portable AC charging gun according to claim 2, characterized in that: One end of the insulating limiting tube (1251) extends into the first sensing groove (1211) and is fixedly connected to the first sensing groove (1211). The second sensing groove (1253) is provided on the side of the insulating limiting tube (1251) near the L1 AC power terminal (131).

4. A portable AC charging gun according to claim 1, characterized in that: The charging gun housing (11) is equipped with a circuit board (17), and a control module is provided on the circuit board (17). The wires of the L1 temperature sensor (124) are connected to the control module.

5. A portable AC charging gun according to any one of claims 1 to 4, characterized in that: It also includes a charging plug (3) and a protector (2), with the two ends of the protector (2) connected to the charging gun body (1) and the charging plug (3) respectively via cables (4).

6. A portable AC charging gun according to claim 5, characterized in that: The charging plug (3) is provided with grounding terminal two (301), N-line terminal two (303), L-line terminal (302), L-line temperature sensor (304) and N-line temperature sensor (305). The probe surfaces of L-line temperature sensor (304) and N-line temperature sensor (305) are coated with insulating varnish. L-line temperature sensor (304) is matched with L-line terminal (302), and N-line temperature sensor (305) is matched with N-line terminal two (303).

7. A portable AC charging gun according to claim 6, characterized in that: The protector (2) is equipped with a temperature collector (201), a leakage current collector (202), a current transformer (203), and a power failure protection device (204). The N-line temperature sensor (305) and the L-line temperature sensor (304) are connected to the temperature collector (201). The charging circuit of the charging gun body (1) is connected to the current transformer (203). The current transformer (203) is connected to the leakage current collector (202). The temperature collector (201), the leakage current collector (202), the charging plug (3), and the charging gun body (1) are all connected to the power failure protection device (204).

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