Intelligent overheat protection device for charging gun and working method

Abstract

The invention relates to an intelligent overheat protection device for a charging gun and a working method. A charging device charges a target charging base; the locking device comprises a metal hook located in the space above the charging device, one end of the metal hook is connected with a hook body, the other end of the metal hook is connected with a button and a shape memory alloy spring, and the middle of the metal hook is hinged to a boss of the charging device through a hook bolt. The locking state is released by pressing the button or shortening the shape memory alloy spring by heating to pull the metal hook; the heat dissipation device dissipates heat for the charging device by using a micro fan; the pop-up device comprises a motor connected with a shape memory push switch, a motor output shaft is movably connected with a pusher through an eccentric wheel and a connecting rod, the shape memory push switch is heated to be closed, and the motor drives the eccentric wheel and the connecting rod to enable the pusher to move linearly to pop up the charging gun. The shape memory alloy is combined with the charging gun, so that the automatic heat dissipation function of the charging gun when the temperature is too high is realized, and a multi-stage thermal protection mechanism is formed.

Description

Technical Field

[0001] The present invention relates to the technical field of charging guns, and in particular to an intelligent overheating protection device and a working method for a charging gun. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Most of the charging guns in the prior art dissipate heat by natural ventilation, which is inefficient. During the charging process, the charging gun is prone to fire accidents due to overheating and spontaneous combustion. In order to solve the above problems, some prior arts use semiconductor refrigeration to protect the charging gun from overheating, such as a patent for a charging gun heat dissipation structure (CN106410493A), which includes an insulating shell, an insulating body, a power terminal and a thermoelectric semiconductor refrigeration component. The heat dissipation structure of the charging gun transfers the heat generated when the terminal is connected to charge to the thermoelectric semiconductor refrigeration component in a timely manner through the heat absorption surface of the thermoelectric semiconductor refrigeration component, and dissipates the above heat through its heat dissipation surface, which can effectively reduce the temperature of the charging gun during charging, thereby eliminating the safety hazards caused by the increase in temperature during charging.

[0004] There are also some existing technologies that use temperature sensors to control the action of the pump to make the coolant flow to achieve overheating protection. For example, a patent for a DC charging gun heat dissipation system (CN211606132U) includes a charging gun and a charging pile. The charging gun has a gun head and a gun seat, and the gun head is provided with a plug for external charging. During the charging process of the charging gun, the controller determines that the temperature data collected by the temperature sensor exceeds the preset temperature threshold. The controller can control the pump to work and make the coolant flow. The coolant takes away the heat in the charging gun and dissipates it into the environment. The coolant circulates back and forth along the delivery pipe until the temperature in the charging gun is maintained within a normal range.

[0005] For example, a patent for a high-power charging gun heat dissipation device (CN217705516U) includes: a box, a liquid storage tank arranged in the box, and a circulating cooling component; the circulating cooling component includes a coolant inlet and outlet, a coolant circulation component, and a heat exchange device. The charging gun heat dissipation device can achieve rapid cooling of the charging gun during high-power charging by circulating liquid cooling.

[0006] There are also some existing technologies that set contacts of specific structures inside the charging gun, and disconnect the contacts when overheated to disconnect the charging circuit. For example, a patent for a new energy vehicle charging gun that automatically cuts off the power when the temperature is too high during charging (CN202210940554.4) proposes a power-off mechanism, and a U-shaped fixed contact is set inside the power-off mechanism. A memory spring is fixedly connected to the right side of the U-shaped fixed contact. When the temperature inside the charging gun is too high, the memory spring will stretch, so that the movable contact rod is separated from the U-shaped fixed contact, and the charging circuit is disconnected, thereby achieving the effect of cutting off the power supply when the temperature inside the charging gun is too high. When the temperature inside the charging gun is too high, the insulating coolant enters the sealed cavity through the connecting hose. At this time, the insulating coolant can dissipate heat from the memory spring and contacts, thereby achieving a cooling effect.

[0007] Although the charging guns of various structural forms mentioned above can achieve overheat protection, they still have some shortcomings, which are as follows:

[0008] Most charging guns use natural heat dissipation, which has low heat dissipation efficiency and is prone to fire accidents due to excessive temperature;

[0009] A few charging guns use overheat protection devices to cool the charging guns through coolant circulation devices or refrigeration components. The working mode is single, the cooling efficiency is low, the structure is complex, and the maintenance cost is high;

[0010] The existing charging gun overheat protection device lacks intelligent detection and alarm devices, and cannot achieve real-time protection during the charging process. When the temperature is too high and on the verge of spontaneous combustion, there is a lack of charging gun pop-up structure or the pop-up structure is improperly designed and is locked and cannot be ejected, which can easily ignite the electric vehicle and charging pile. Summary of the invention

[0011] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides an intelligent overheat protection device and working method for a charging gun, which combines shape memory alloy with the charging gun to realize the function of automatic heat dissipation of the charging gun when the temperature is too high. The heat dissipation device uses a micro fan for heat dissipation, and its heat dissipation effect is significant. A pop-up device and an alarm structure are also added. When the temperature of the charging gun is unnaturally high during charging, the charging gun can be effectively ejected. At the same time, the buzzer is powered on and an alarm is sounded, which can effectively avoid the occurrence of safety hazards.

[0012] In order to achieve the above object, the present invention adopts the following technical solution:

[0013] A first aspect of the present invention provides an intelligent overheat protection device for a charging gun, comprising:

[0014] A charging device, used to receive the current from the charging pile and charge the target charging station;

[0015] A locking device, used to lock the charging device after it is connected to the target charging dock;

[0016] A heat dissipation device is arranged inside the charging device and uses flowing air to dissipate heat for the charging device;

[0017] An ejection device, used to push the charging device away from the target charging station;

[0018] Among them, the locking device includes a metal hook located in the space above the charging device, one end of the metal hook is connected to the hook body, the upper surface of the other end is connected to the button, and the lower surface is connected to the top of the shape memory alloy spring. The middle part of the metal hook is hinged to the boss of the charging device through a hook bolt. The metal hook is pulled by pressing the button or the shape memory alloy spring is shortened due to heat, so that one end of the hook body of the metal hook rises and the locking state is released.

[0019] Furthermore, the charging device includes a plug, a plug base and a boss, a plug is provided at one end of the plug base, a boss is provided at the upper part of the plug base, and a conductor in the plug is used to connect to a target charging base.

[0020] Further, the area between the metal hook connection button and the hook bolt abuts against the protrusion of the micro switch.

[0021] Furthermore, the micro switch is located in the accommodating cavity of the base of the locking device. When the button is pressed or the shape memory alloy spring is shortened by heat, one end of the metal hook is pulled and the micro switch is triggered through the protrusion, thereby switching the output current state between the charging pile and the charging gun.

[0022] Furthermore, the bottom end of the shape memory alloy spring is connected to the charging gun housing.

[0023] Furthermore, the heat dissipation device includes a micro fan, which is connected to the circuit through a shape memory heat dissipation switch, and the micro fan is connected to the charging gun housing through a fan base; the shape memory heat dissipation switch is closed when heated, and the circuit is turned on to start the micro fan to blow out flowing air to achieve heat dissipation.

[0024] Furthermore, the pop-up device includes a motor connected to a shape memory push switch, the motor output shaft is connected to an eccentric wheel, the eccentric wheel is movably connected to a pusher through a connecting rod, the shape memory push switch is closed when heated, so that the motor drives the eccentric wheel to rotate, and the eccentric wheel drives the connecting rod to make the pusher move in a straight line, so that the charging gun is ejected by pushing the target socket.

[0025] Furthermore, the shape memory push switch is also connected to a buzzer.

[0026] Furthermore, the pop-up device includes a piezoelectric stack device connected to a shape memory push switch. The piezoelectric stack device is located inside the plug. An inner section of the piezoelectric stack device is fixedly connected to the plug. When the power is turned on, the piezoelectric stack device uses the thickness change brought about by the inverse piezoelectric effect to push the plug out of the target socket.

[0027] A second aspect of the present invention provides a working method of an intelligent overheat protection device for a charging gun, comprising the following steps:

[0028] The charging gun generates heat when working. When the internal temperature of the charging gun rises to the deformation temperature of the shape memory heat dissipation switch, the shape memory heat dissipation switch is closed, and the micro fan works to dissipate heat from the charging device.

[0029] When the temperature continues to rise, the shape memory alloy spring shortens, pulling the metal hook to trigger the micro switch, cutting off the power supply, and no longer supplying power to the charging gun. The hook body end of the metal hook is lifted, releasing the locking state;

[0030] The shape memory push switch closes, the buzzer is energized to sound an alarm, and the ejection device is actuated to eject the charging gun from the target socket.

[0031] Compared with the prior art, one or more of the above technical solutions have the following beneficial effects:

[0032] 1. A shape memory alloy spring is set at the tail end of the metal hook of the locking device. When the temperature of the charging gun rises to a certain level, the shape memory alloy spring contracts and pulls the metal hook, causing the hook body at the head end of the metal hook to lift up, thereby releasing the locking state of the charging gun, making it easier for the charging gun to be quickly pulled out of the target charging seat, and ensuring that the subsequent pop-up device can be reliably popped out, avoiding the charging gun from being locked and unable to be pulled out of the charging seat at high temperature, causing greater safety hazards.

[0033] 2. It has a multi-level working mechanism. When the temperature exceeds a certain value, the fan in the heat dissipation device is used to achieve overheat protection. If the temperature continues to rise, the power supply of the charging gun is disconnected. If it continues to rise, the charging gun is ejected from the socket. By taking different overheat protection measures for the charging gun at different temperatures, it not only has the effect of rapid cooling, but also can disconnect the power supply in time when the unnatural temperature is too high, preventing the electric vehicle and charging pile from igniting and avoiding fire.

[0034] 3. The use of intelligent materials such as shape memory alloys and piezoelectric materials not only has high sensitivity and fast response, but also has simple structure and strong practicality, greatly reducing manufacturing costs.

[0035] 4. It has intelligent detection and alarm devices, which can provide real-time protection during the operation of the charging gun. The charging gun has an additional pop-up device, which can realize automatic pop-up in uncontrollable situations and improve safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0037] Figure 1 It is a schematic diagram of the structure of the intelligent overheat protection device for a charging gun provided in the first embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the principle of the two-way memory alloy effect provided by the first embodiment of the present invention;

[0039] Figure 3 is a schematic diagram of the structure of a charging device provided in Embodiment 1 of the present invention;

[0040] Figure 4 is a schematic structural diagram of a locking device provided in Embodiment 1 of the present invention;

[0041] Figure 5 is a schematic diagram of the change in the position of the metal hook at different temperatures provided by the first embodiment of the present invention;

[0042] Figure 6 is a schematic structural diagram of a heat dissipation device provided in Embodiment 1 of the present invention;

[0043] Figure 7 It is a schematic diagram of the shape memory fan switch and the shape memory push switch provided in the first embodiment of the present invention;

[0044] Figure 8 is a schematic diagram of a pop-up device provided in Embodiment 1 of the present invention;

[0045] Fig. 9 is a schematic diagram of the explosion structure of the ejection device provided in the first embodiment of the present invention;

[0046] Fig.10 This is a schematic diagram of the structure of the charging gun housing provided in the first embodiment of the present invention;

[0047] Fig.11 It is a schematic diagram of the structure of the intelligent overheat protection device for a charging gun provided in the second embodiment of the present invention;

[0048] Fig.12 is a schematic diagram of the inverse piezoelectric effect principle provided by the second embodiment of the present invention;

[0049] Fig.13 is a schematic structural diagram of a heat dissipation device provided in Embodiment 2 of the present invention;

[0050] Fig.14 and Fig.15is a schematic diagram of the structure of the ejection device at different temperatures provided by the second embodiment of the present invention;

[0051] Fig.16 It is a schematic diagram of the structure of the charging gun housing provided in the second embodiment of the present invention.

[0052] In the figure: 1. Charging device; 2. Locking device; 3. Heat dissipation device; 4. Ejection device; 5. Charging gun housing;

[0053] 1-1, plug; 1-2, plug base; 1-3, boss;

[0054] 2-1, button; 2-2, metal hook; 2-3, shape memory alloy spring; 2-4, micro switch; 2-5, hook bolt;

[0055] 3-1. Micro fan; 3-2. Shape memory heat dissipation switch; 3-3. Fan base;

[0056] 4-1, shape memory push switch; 4-2, motor buckle; 4-3, motor; 4-4, eccentric wheel; 4-5, connecting rod; 4-6, eccentric wheel connecting rod bolt; 4-7, connecting rod pusher bolt; 4-8, pusher; 4-9, buzzer; 4-10, piezoelectric stacking mechanism;

[0057] 5-1, housing; 5-2, locking device base; 5-3, heat dissipation device base; 5-4, ejection device base; 5-5, metal chuck. DETAILED DESCRIPTION

[0058] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0059] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0060] It should be noted that the terms herein are only intended to describe specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0061] Shape memory alloy, a metal material with unique properties, has a shape memory effect. When the material has undergone deformation, it will return to its original shape by heating to a certain temperature. Shape memory alloys also exhibit superelasticity under certain conditions, that is, they can return to their original shape when deformed by force, and there is almost no energy loss during the deformation process. The inverse piezoelectric effect refers to the phenomenon that the application of an alternating electric field to a dielectric causes mechanical deformation of the dielectric. That is, when an electric field is applied in the polarization direction of the dielectric, these dielectrics will deform, and when the electric field is removed, the deformation of the dielectric disappears. Compared with traditional mechanical drive structures, the advantages of shape memory alloy structures and piezoelectric structures mainly include simple structure, easy integration, rapid response, high sensitivity, high precision, corrosion resistance, high damping, etc., which make them widely used in the engineering field.

[0062] The following embodiment provides an intelligent overheat protection device for a charging gun and a working method. The shape memory alloy is combined with the charging gun to realize the function of automatically dissipating heat when the temperature is too high. The heat dissipation device uses a micro fan to dissipate heat, and its heat dissipation effect is significant. A pop-up device and an alarm structure are also added. When the temperature of the charging gun is unnaturally high during charging, the charging gun can be effectively ejected. At the same time, the buzzer is powered on and an alarm is sounded, which can effectively avoid the occurrence of safety hazards.

[0063] Embodiment 1:

[0064] An intelligent overheat protection device for a charging gun, comprising:

[0065] A charging device 1, used to receive current from a charging pile and charge a target;

[0066] The locking device 2 is used to lock the charging device 1 after it is connected to the target to avoid accidental separation and ensure that the charging process is carried out reliably;

[0067] The heat dissipation device 3 is arranged at the rear of the charging device 1 and uses flowing air to dissipate heat for the charging device 1;

[0068] The ejection device 4 is used to push the charging device 1 away from the target.

[0069] In this embodiment, the intelligent overheat protection device for the charging gun includes a charging device 1, a locking device 2, a heat dissipation device 3, a pop-up device 4 and a charging gun housing 5. The specific structure is as follows: Figure 1 shown.

[0070] Among them, the charging device 1 is used to receive the current of the charging pile and charge the target; the locking device 2 is used to lock the charging device 1 after it is connected to the target to avoid accidental separation and ensure the reliable charging process; the heat dissipation device 3 is arranged at the rear of the charging device 1, and uses the flowing air to dissipate the heat of the charging device 1; the pop-up device 4 is used to push the charging device away from the target when in action.

[0071] The charging gun uses shape memory alloy materials in many places. The shape memory alloy material has a two-way shape memory effect. The principle is as follows Figure 2 shown.

[0072] The two-way shape memory effect refers to the phenomenon that after a shape memory alloy undergoes a large plastic deformation in the low-temperature martensite state, it recovers to the shape of the high-temperature austenite by heating, and when cooled again, it can fully or partially return to the low-temperature martensite shape.

[0073] like Figure 3 As shown, the charging device 1 includes a plug 1-1, a plug base 1-2 and a boss 1-3. The charging gun plug 1-1 and the plug base 1-2 are fixedly connected, the boss 1-3 is located at the upper end of the plug base 1-2, and the plug base 1-2 and the boss 1-3 are the same whole. The charging gun plug 1-1 is the main heat generating part, which emits a large amount of heat and is simultaneously transferred to the plug base 1-2. Therefore, the charging gun plug 1-1 and the plug base 1-2 are made of high temperature resistant materials, such as polycarbonate (PC), polyimide (PI) or polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET) and other materials.

[0074] like Figure 4 As shown, the locking device 2 includes a button 2-1, a metal hook 2-2, a shape memory alloy spring 2-3, a micro switch 2-4 and a hook bolt 2-5.

[0075] The locking device 2 is located in the upper space of the charging device 1. One end of the metal hook 2-2 is the hook body, and the other end is connected to the bottom end of the button 2-1 at the top and the top end of the shape memory alloy spring 2-3 at the bottom. The middle part of the metal hook 2-2 is hinged to the boss 1-3 through the hook bolt 2-5, so that the two ends of the metal hook 2-2 can move up and down alternately. Figure 5 When the shape memory alloy spring 2-3 is shortened or the button 2-1 is pressed, the metal hook 2-2 uses the hook bolt 2-5 as a rotation point, and the hook body end of the metal hook 2-2 is lifted to release the locking state.

[0076] The area between the metal hook 2-2 connecting the button 2-1 and the hook bolt 2-5 abuts against the protrusion of the micro switch 2-4. The micro switch 2-4 is located in the square accommodation cavity of the locking device base 5-2. The metal hook 2-2 is above the micro switch 2-4. When the button 2-1 is pressed or the shape memory alloy spring 2-3 is shortened by high temperature, one end of the metal hook 2-2 is pulled, causing the micro switch 2-4 to collide with the metal hook 2-2. When the micro switch 2-4 is triggered, the output current state between the charging pile and the charging gun is switched.

[0077] The protrusion of the metal hook 2-2 that triggers the micro switch 2-4 is a cylindrical protrusion. The bottom end of the metal hook 2-2 fixes one end of the shape memory alloy spring 2-3 through the cylindrical protrusion. The locking device base 5-2 also has a cylindrical protrusion that fixes the other end of the shape memory alloy spring 2-3.

[0078] like Figure 6 As shown, the heat dissipation device 3 includes a micro fan 3-1, a shape memory heat dissipation switch 3-2 and a fan base 3-3. The micro fan 3-1 is connected to the shape memory heat dissipation switch 3-2 circuit, and the lower end of the micro fan 3-1 is fixedly connected to the heat dissipation device base 5-3 through the fan base 3-3. The shape memory heat dissipation switch 3-2 uses a shape memory alloy that also has a two-way shape memory effect. The geometric shape changes with the change of temperature. The principle is as follows Figure 7 shown.

[0079] like Figure 8 and Fig. 9 As shown, the pop-up device 4 includes a shape memory push switch 4-1, a motor buckle 4-2, a motor 4-3, an eccentric wheel 4-4, a connecting rod 4-5, an eccentric wheel connecting rod bolt 4-6, a connecting rod pusher bolt 4-7, a pusher 4-8 and a buzzer 4-9. One end of the shape memory push switch 4-1 circuit is connected to the power supply, and the other end is connected to the buzzer 4-9 and the motor 4-3 at the same time. The output shaft of the motor 4-3 is key-connected with the eccentric wheel 4-4, and the other side of the eccentric wheel 4-4 is connected to the connecting rod 4-5 through the eccentric wheel connecting rod bolt 4-6, and the other end of the connecting rod 4-5 is connected to the pusher 4-8 through the connecting rod pusher bolt 4-7. The motor 4-3 is located in the accommodating cavity on one side of the pop-up device base 5-4, and the accommodating cavity fixes the motor 4-3 by cooperating with the motor buckle 4-2, and the buzzer 4-9 is located in the accommodating cavity on the other side of the pop-up device base 5-4.

[0080] When the shape memory push switch 4-1 is closed, the motor 4-3 drives the eccentric wheel 4-4 to rotate, the eccentric point on the eccentric wheel 4-4 drives one end of the connecting rod 4-5, and the other end of the connecting rod 4-5 drives the pusher 4-8 to move in a straight line. The pusher 4-8 moving in a straight line abuts against the target and gradually moves the charging gun away from the target, so that the charging gun pops out when the locking device 2 is in the unlocked state.

[0081] like Fig.10 As shown, the charging gun housing 5 includes a housing 5-1, a locking device base 5-2, a heat sink base 5-3, an ejection device base 5-4, and a metal chuck 5-5. The housing 5-1, the locking device base 5-2, the heat sink base 5-3, and the ejection device base 5-4 are a whole. The metal chuck 5-5 is located at the rear of the housing 5-1 and is fixedly bonded to the housing 5-1.

[0082] In this embodiment, the shape memory alloy spring, shape memory heat dissipation switch, and shape memory push switch use shape memory alloys with two-way shape memory effect, such as Ni-Ti based, Cu based, Fe based, Ag based, Au based, Co based, etc.

[0083] The height of the shape memory alloy spring changes with temperature. It is in an extended state at normal temperature and in a compressed state at high temperature.

[0084] The principle of heat dissipation and protection achieved by the above device is as follows:

[0085] When the charging gun button is pressed, the micro switch is triggered, the charging pile outputs current to the charging gun, and the charging gun starts working.

[0086] During operation, the heat generated by the plug causes the temperature of the charging gun to rise. When the temperature is too high, the shape memory heat dissipation switch in the heat dissipation device automatically closes, and the micro fan starts working to speed up the gas flow to reduce the temperature at the charging device.

[0087] When the temperature continues to rise due to special circumstances, the shape memory alloy spring begins to shorten, the microswitch is triggered again, the charging pile no longer outputs current to the charging gun, and the other end of the metal hook is tilted to facilitate the removal of the charging gun. At the same time, the shape memory push switch automatically closes, the pop-up device circuit is energized, the buzzer sounds an alarm, the motor rotates, and the connecting rod is driven by the motor to push the pusher back and forth, and the charging gun is pulled out to avoid fire.

[0088] The charging gun has a multi-stage working mechanism and can be adjusted at different temperatures. It not only has the effect of rapid cooling, but also can disconnect the power supply in time when the temperature is unnaturally high, preventing the electric vehicle and charging pile from igniting and avoiding the occurrence of fire.

[0089] The charging gun uses intelligent materials such as shape memory alloy and piezoelectric material. It not only has high sensitivity and fast response, but also has a simple structure and strong practicality, which greatly reduces manufacturing costs.

[0090] The charging gun has an intelligent detection and alarm device, which can provide real-time protection during the operation of the charging gun. The charging gun is also equipped with a pop-up device to achieve automatic pop-up in uncontrollable situations, thereby improving safety and filling the gap in related technologies.

[0091] Embodiment 2:

[0092] In this embodiment, the overheat protection device includes a charging device 1, a locking device 2, a heat dissipation device 3, an ejection device 4 and a charging gun housing 5. Fig.11 shown.

[0093] This embodiment does not use an ejection device consisting of an eccentric wheel, a connecting rod and a pusher, but instead uses the thickness change of the piezoelectric stack formed by the inverse piezoelectric effect to achieve ejection.

[0094] In this embodiment, the pop-up device 4 includes a shape memory push switch 4-1 and a piezoelectric stack device 4-10. Fig.13 As shown, the piezoelectric stack device 4-10 is connected to the shape memory heat dissipation switch 3-2 circuit, the piezoelectric stack device 4-10 is located in the plug 1-1 jack, and the inner side of the piezoelectric stack device 4-10 is fixedly connected to the plug 1-1. Fig.12 As shown, when the power is turned on, the electrical energy is converted into mechanical energy and the piezoelectric stack device 4-10 becomes thicker.

[0095] like Fig.14 As shown, at room temperature, the shape memory heat dissipation switch 3-2 is disconnected, and the piezoelectric stack device 4-10 does not deform. At high temperatures, the shape memory heat dissipation switch 3-2 is less sensitive to temperature than the push switch 4-1. Therefore, the shape memory heat dissipation 3-2 is closed first, and the shape memory push switch 4-1 is still in the disconnected state. At this time, the heat dissipation device 3 cools the charging gun, and the ejection device 4 does not work. When a special situation occurs, the temperature of the charging gun continues to rise, and the shape memory push switch 4-1 is also closed, such as Fig.15 As shown, the piezoelectric stack device 4-10 converts electrical energy into mechanical energy, the piezoelectric stack device 4-10 extends, and the charging gun is pushed out to avoid the occurrence of fire.

[0096] The rest are the same as in Example 1.

[0097] In this embodiment, the structure of the charging gun housing 5 is as follows: Fig.16 As shown, it includes a shell 5-1, a locking device base 5-2, a heat sink base 5-3 and a metal chuck 5-5.

[0098] Embodiment three:

[0099] A working method of an intelligent overheat protection device for a charging gun, comprising the following steps:

[0100] The charging gun generates heat when working. When the internal temperature of the charging gun rises to the deformation temperature of the shape memory heat dissipation switch, the shape memory heat dissipation switch is closed, and the micro fan works to dissipate heat from the charging device.

[0101] When the temperature continues to rise, the shape memory alloy spring shortens, pulling the metal hook to trigger the micro switch, cutting off the power supply, and no longer supplying power to the charging gun. The hook body end of the metal hook is lifted, releasing the locking state;

[0102] The shape memory push switch closes, the buzzer is energized to sound an alarm, and the ejection device is actuated to eject the charging gun from the target socket.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An intelligent overheat protection device for a charging gun, characterized in that: include: A charging device, used to receive the current from the charging pile and charge the target charging station; A locking device, used to lock the charging device after it is connected to the target charging dock; A heat dissipation device is arranged at the rear of the charging device and uses flowing air to dissipate heat for the charging device; An ejection device, used to push the charging device away from the target charging station; Among them, the locking device includes a metal hook located in the space above the charging device, one end of the metal hook is connected to the hook body, the upper surface of the other end is connected to the button, and the lower surface is connected to the top of the shape memory alloy spring. The middle part of the metal hook is hinged to the boss of the charging device through a hook bolt. The metal hook is pulled by pressing the button or the shape memory alloy spring is shortened due to heat, so that one end of the hook body of the metal hook rises and the locking state is released.

2. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The charging device comprises a plug, a plug base and a boss. A plug is arranged at one end of the plug base, a boss is arranged at the upper part of the plug base, and a conductor in the plug is used to connect with a target charging base.

3. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The area between the metal hook connection button and the hook bolt abuts against the protrusion of the micro switch.

4. The intelligent overheat protection device for a charging gun according to claim 3, characterized in that: The micro switch is located in the accommodating cavity of the locking device base. When the button is pressed or the shape memory alloy spring is shortened by heat, one end of the metal hook is pulled and the micro switch is triggered by the protrusion, thereby switching the output current state between the charging pile and the charging gun.

5. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The bottom end of the shape memory alloy spring is connected inside the charging gun housing.

6. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The heat dissipation device includes a micro fan, which is connected to the circuit through a shape memory heat dissipation switch, and the micro fan is connected to the charging gun housing through a fan base; the shape memory heat dissipation switch is closed when heated, and the circuit is turned on to start the micro fan to blow out flowing air to achieve heat dissipation.

7. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The pop-up device includes a motor connected to a shape memory push switch, the motor output shaft is connected to an eccentric wheel, the eccentric wheel is movably connected to a pusher through a connecting rod, the shape memory push switch is closed when heated, the motor drives the eccentric wheel to rotate, the eccentric wheel drives the connecting rod to make the pusher move in a straight line, and the charging gun is ejected by pushing the target socket.

8. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The shape memory push switch is also connected to a buzzer.

9. The intelligent overheat protection device for a charging gun according to claim 1, characterized in that: The pop-up device includes a piezoelectric stack device connected to a shape memory push switch. The piezoelectric stack device is located in the plug, and an inner section of the piezoelectric stack device is fixedly connected to the plug. When the power is turned on, the piezoelectric stack device uses the thickness change brought about by the inverse piezoelectric effect to push the plug out of the target socket.

10. A working method of the intelligent overheat protection device for a charging gun according to any one of claims 1 to 9, characterized in that: The following steps are involved: The charging gun generates heat when working. When the internal temperature of the charging gun rises to the deformation temperature of the shape memory heat dissipation switch, the shape memory heat dissipation switch is closed, the micro fan works, and the heat dissipation device is used to dissipate heat from the charging device. When the temperature continues to rise, the shape memory alloy spring shortens, pulling the metal hook to trigger the micro switch, cutting off the power supply, and no longer supplying power to the charging gun. The hook body end of the metal hook is lifted, releasing the locking state; The shape memory push switch closes, the buzzer is energized to sound an alarm, and the ejection device actuates to eject the charging gun from the target socket.

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