An air switch for an integrated DC converter in an electric vehicle

Abstract

This invention discloses an air switch for an integrated DC converter in electric vehicles. Existing electric vehicles require three main power lines to supply power to the entire vehicle, onboard electrical components, and a cloud upload module. To address this, this invention solves the problems of complex cabling between the electric vehicle's DC converter and the air switch, and poor main power line safety. It provides an improved air switch that integrates a voltage conversion unit without altering the existing air switch structure. The voltage conversion unit draws power directly from the air switch's internal circuit, simplifying and eliminating the original two main power line cables, significantly improving main power line safety. Redesigning a new air switch structure integrating this function requires substantial R&D investment; this invention quickly fills this market gap and utilizes existing air switches, avoiding resource waste.

Description

Technical Field

[0001] This invention relates to the field of air switch technology, and in particular to an air switch for an integrated DC converter for electric vehicles. Background Technology

[0002] Electric vehicles equipped with air switches can disconnect the circuit in time when a short circuit or overload occurs, thus cutting off the power to the entire electric vehicle circuit system and protecting the vehicle's safety and lifespan. However, with the promulgation of the "Guidelines for Digital Management of Electric Vehicles," vehicles are required to upload data to the cloud in real time. Therefore, in the event of a short circuit or overload, electric vehicles also need to provide an uninterrupted DC 6V power supply to the cloud upload module and central control unit.

[0003] In existing technology, the DC step-down converter and circuit breaker used to convert the main line voltage of electric vehicles are designed independently. Three circuits (DC36-60V) need to be connected from the main line of the electric vehicle. One circuit is controlled by the circuit breaker to supply power to the vehicle. The second circuit is stepped down to 12V by the DC step-down converter and then connected to the circuit breaker to supply power to the vehicle's electrical appliances, and is also controlled by the circuit breaker to supply power. The third circuit needs to provide uninterrupted 6V power for uploading to the cloud. This circuit is used after the main line is connected to the DC step-down converter to step down to 6V. This circuit is not controlled by the circuit breaker to supply power, thus enabling uninterrupted data uploading.

[0004] The problem is that connecting the DC step-down converter and the circuit breaker with cables results in long and complex wiring, and the main cable power supply also poses safety hazards. Designing a new circuit breaker that simultaneously performs both step-down and circuit breaker functions would require significant R&D investment and sunk costs, and previously released or stocked circuit breakers cannot be reused, leading to resource waste. Summary of the Invention

[0005] This application addresses the shortcomings of the prior art by providing a reasonably structured integrated DC converter air switch. Without altering the existing air switch structure, the voltage conversion unit can be integrated into the air switch through integrated design. The two main lines requiring voltage reduction can directly draw power from the inside of the air switch, reducing the number of two (DC36-60V) main line circuits. This significantly optimizes the power safety of the main cables, simplifies electrical wiring, and makes the process more convenient.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] An air switch for an integrated DC converter in an electric vehicle includes a circuit breaker. The circuit breaker is equipped with a contact mechanism, an arc extinguishing mechanism, a linkage device, and a tripping mechanism. The circuit breaker is also equipped with a voltage conversion unit. The voltage conversion unit includes a flame-retardant housing and a first step-down module and a second step-down module built therein. The first step-down module is connected to the input voltage terminal of the circuit breaker, and the second step-down module is connected to the output voltage terminal of the circuit breaker.

[0008] Furthermore, the voltage output terminal of the first step-down module is connected to the central control and cloud upload module. The input voltage of the first step-down module is 48-60V, and its output voltage is 5-6V.

[0009] Furthermore, the voltage output terminal of the second step-down module is connected to other on-board electrical components of the electric vehicle. The input voltage of the second step-down module is 48V, and its output voltage is 12V.

[0010] Furthermore, the contact mechanism includes an input contact and an output contact, the input contact being arranged for the input voltage, and the output contact being used to control the connection and disconnection of the load.

[0011] Furthermore, the arc-extinguishing mechanism is an arc-extinguishing cover, which is composed of multiple insulating metal plates arranged on one side of the contact point between the end of the connecting rod device and the input voltage contact point of the contact mechanism, and is used to guide and extinguish the sparks generated at the moment the contact point is disconnected.

[0012] Furthermore, the linkage device includes an operating handle on top of the circuit breaker and a movable contact controlled by the operating handle to open and close. The movable contact is normally connected to the tripping mechanism so that current from the input contact flows through the output contact to the load.

[0013] Furthermore, the tripping mechanism includes an electromagnetic tripping assembly and a thermal tripping assembly.

[0014] Furthermore, the electromagnetic tripping assembly is an electromagnetic coil, and the thermal tripping assembly is a bimetallic strip composed of two different metals. Under normal conditions, the current flows from the input contact through the electromagnetic coil and then through the bimetallic strip to the load.

[0015] The beneficial effects of this invention are as follows:

[0016] The original electric vehicle's DC step-down converter and air switch were designed independently. The electric vehicle needed to connect three main lines to supply power to the whole vehicle, on-board electrical components, and cloud upload module respectively. The long and complicated wiring caused inconvenience and safety hazards.

[0017] Compared with the prior art, the circuit breaker designed in this invention has two sets of step-down modules in the integrated voltage conversion unit. The wiring of each module runs between the original circuit breaker and the housing of the integrated voltage conversion unit, and the power is directly drawn from inside the circuit breaker. This can directly reduce the need to draw two main circuits (DC36-60V) from the electric vehicle, and significantly optimize the power safety of the main cable.

[0018] The first step-down module of this invention is connected from the input terminal inside the circuit breaker, providing uninterruptible power to the first step-down module and outputting DC5-6V, thereby providing uninterrupted power to the central control and cloud upload modules, in compliance with the current laws and regulations related to electric vehicles; the second step-down module is connected from the inside of the circuit breaker near the output terminal, providing input voltage to the second step-down module and outputting DC12V, and is de-energized when the circuit breaker is open, and provides power to other electrical components of the electric vehicle when the circuit breaker is closed.

[0019] Without changing the existing circuit breaker's structural design and internal layout, redesigning a new circuit breaker structure that integrates this function would require a large amount of R&D investment. This invention can quickly fill the market gap in the short term, while making use of the existing circuit breakers and avoiding resource waste. Attached Figure Description

[0020] Figure 1 This is a diagram showing the internal structure of the circuit breaker (air switch) of the present invention;

[0021] Figure 2 This is a wiring diagram showing the separation of the air switch and the voltage conversion unit in this invention.

[0022] Figure 3 This is a state diagram of the separation process according to the present invention;

[0023] Figure 4 This is a state diagram during the assembly and integration of the present invention.

[0024] The components include: 1. Circuit breaker; 2. Contact mechanism; 21. Input contact; 22. Output contact; 3. Arc extinguishing mechanism; 4. Linkage device; 41. Operating handle; 42. Movable contact; 5. Tripping mechanism; 51. Electromagnetic tripping assembly; 52. Thermal tripping assembly; 6. Voltage conversion unit; 61. Flame-retardant housing; 62. First step-down module; 63. Second step-down module; 64. First cable; 65. Second cable; 66. Step-down output port; 7. Fastener; 8. Wiring hole. Detailed Implementation

[0025] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0026] The original electric vehicle's DC step-down converter and air switch were designed independently. The electric vehicle needed to connect three main lines to supply power to the whole vehicle, on-board electrical components, and cloud upload module respectively. The long and complex wiring caused inconvenience and safety hazards. Redesigning the air switch structure with integrated step-down requires a lot of R&D investment. At the same time, the development of new products will directly lead to the delay of the launch of air switches and inventory, and waste of resources.

[0027] To address this pain point, the present invention provides an air switch with an integrated DC converter for electric vehicles, which does not require changes to the existing air switch product structure. The voltage conversion unit 6 is integrated on one side of the air switch housing, and the two are fixed or detachably connected.

[0028] like Figures 1-4 Specifically, an air switch for an integrated DC converter in an electric vehicle includes a circuit breaker 1, which includes, but is not limited to, an air switch (circuit breaker). The air switch contains a contact mechanism 2, an arc-extinguishing mechanism 3, a linkage device 4, and a tripping mechanism 5. Furthermore, a voltage conversion unit 6 is configured on one side of the air switch. The voltage conversion unit 6 includes a flame-retardant housing 61 and a first step-down module 62 and a second step-down module 63 embedded therein. The first step-down module 62 is connected to the input voltage terminal of the circuit breaker 1, and the second step-down module 63 is connected to the output voltage terminal of the circuit breaker 1. It should be noted that both the air switch and the voltage conversion unit 6 also include a flame-retardant housing 61 covering the outer periphery of the components. Through-holes can be drilled at all four ends between the two housings, and the flame-retardant housings 61 are integrated together using fasteners such as screws, thereby simplifying the structure, reducing the size, and achieving high integration. Corresponding openings are required between adjacent housings for internal wiring of the two step-down modules.

[0029] Through the above technical solutions, the selection of circuit breakers includes, but is not limited to, Siemens 5SJ6120-7CR. By adding a voltage conversion unit to the structure of this circuit breaker, it is possible to avoid the need to develop a new circuit breaker structure, while also utilizing existing inventory and achieving the optimization goal of reducing the number of main cables.

[0030] In some embodiments, the voltage output terminal of the first step-down module 62 is connected to the central control and cloud upload module. The input voltage of the first step-down module 62 is 48-60V, and its output voltage is 6V. This includes, but is not limited to, using TMR 6-4812, which is a 6V, 1A step-down module launched by TRACO Power Supply Co., Ltd., with an input voltage of 48V and dimensions of 19.5mm x 11.2mm x 9.5mm. In other embodiments, the first step-down module 62 can be OKL-T / 6-W12N-C: this model is a 6V 1A step-down module launched by Murata, with an input voltage range of 9V to 18V and dimensions of 11.6mm x 6.3mm x 3.0mm.

[0031] In some embodiments, the voltage output terminal of the second step-down module 63 is connected to other on-board electrical components of the electric vehicle. The second step-down module 63 includes, but is not limited to, the use of TSR 1-24120: this model is a 12V 1A step-down module launched by TRACO Power Supply Co., Ltd., with an input voltage of 48V and dimensions of 19.5mm x 11.2mm x 9.5mm. In other embodiments, a circuit breaker of model OKL-T / 12-W12N-C can also be selected: this model is a 12V 1A step-down module launched by Murata, with an input voltage of 48V and dimensions of 11.6mm x 6.3mm x 3.0mm, suitable for automotive, industrial, and communication equipment.

[0032] In some embodiments, the contact mechanism 2 includes an input contact 21 and an output contact 22, such as Figure 1 As shown, the input contact 21 is arranged on the right side of the circuit breaker flame-retardant housing 61, and is used by the user to input voltage when connecting cables. The output contact is arranged on the left side of the circuit breaker flame-retardant housing 61, and is used to control the connection and disconnection of the load.

[0033] In some embodiments, the arc extinguishing mechanism 3 is an arc extinguishing cover, which is composed of multiple insulating metal plates arranged on one side of the contact point between the contact piece at the end of the linkage device 4 and the input contact 21. When the metal contact piece contacts the contact piece led out from the input contact 21, the circuit is thus connected. When the linkage device 4 is activated, its attached contact piece moves away from the contact piece of the input contact 21, thereby achieving short circuit or short circuit protection. At the moment the circuit is disconnected, sparks will be generated at the contact point, which need to be extinguished in time. The multiple insulating metal plates guide and extinguish the sparks generated at the moment the contact point is disconnected.

[0034] In some embodiments, the linkage device 4 includes an operating handle 41 on top of the circuit breaker 1 and a movable contact 42 controlled by the operating handle 41. The structure of the linkage device 4 is shown in the figure, and its principle and design are conventional techniques in the art, which will not be described in detail here. The movable contact 42 is normally connected to the tripping mechanism 5 so that the current from the output contact 22 flows through the output contact 22 to the load. At this time, the metal contact piece on the movable contact 42 is in contact with the contact piece of the input contact 21. When the circuit is overloaded or short-circuited, if either the bimetallic strip or the electromagnetic coil in the tripping mechanism 5 exceeds the limit value, it will cause the movable contact 42 to disengage, causing the metal contact piece at its end to separate from the contact piece of the input contact 21, thereby achieving circuit protection.

[0035] In some embodiments, the tripping mechanism 5 includes an electromagnetic tripping component 51 and a thermal tripping component 52; the electromagnetic tripping component 51 is an electromagnetic coil, and the thermal tripping component 52 is a bimetallic strip composed of two different metals. Under normal conditions, the current flows from the input contact through the electromagnetic coil and then through the bimetallic strip to the load.

[0036] It's important to note that the bimetallic strip in an air switch is typically composed of two metals with different coefficients of thermal expansion, such as iron and copper. When the circuit is overloaded, the current increases, leading to a rapid increase in heat. This heats the bimetallic strip, and the different metals elongate to varying degrees due to their different coefficients of thermal expansion, causing the entire bimetallic strip to bend or twist. In an air switch, the bimetallic strip is connected to an electromagnetic coil via electrical contacts to switch the circuit. When current flows through the contacts, it generates heat, causing the bimetallic strip to heat up and bend. When the bimetallic strip bends to a certain angle, the part in contact with the contacts disengages, interrupting the circuit. Once the current stops flowing through the contacts, the bimetallic strip cools down and returns to its original state, thus closing the circuit.

[0037] It should be noted that the electromagnetic trip unit is connected in series with the protected circuit for short-circuit protection. When a normal current flows through the circuit, the electromagnetic force generated by the electromagnet is less than the tension of the reaction spring, and the armature cannot be attracted by the electromagnet, allowing circuit breaker 1 to operate normally. When a short-circuit fault occurs in the circuit, the current exceeds the normal current by several times. The electromagnetic force generated by the electromagnet is greater than the force of the reaction spring, and the armature is attracted by the electromagnet, which pushes the trip mechanism 5 to release the main contacts via the transmission mechanism. The main contacts then separate under the action of the tripping spring, cutting off the circuit and providing short-circuit protection.

[0038] The working principle of this invention is as follows: Based on the principle of the circuit breaker described above, the principle of integrating the voltage conversion unit 6 to reduce the number of main lines is as follows:

[0039] The voltage conversion unit 6 includes a flame-retardant housing 61 and two built-in step-down modules. The first step-down module 62 and the second step-down module 63 can be soldered onto a circuit board or arranged in other ways within the flame-retardant housing 61. Figure 2As shown, two wiring holes 8 are correspondingly opened on the flame-retardant housing 61 of the open flame-retardant housing and the flame-retardant housing 61 of the voltage conversion unit 6. The first step-down module 62 is used to provide a 6V step-down output for uninterruptible power supply to the cloud module, so its terminals are soldered to the contact piece (fixed connection) of the input contact 21 through the first cable 64; the second step-down module 63 is used to provide 12V power supply to the on-board electrical components of the electric vehicle, so its terminals are connected to the metal piece connected to the output contact 22 through the second cable 65; with this configuration, the direct The original two circuits connecting the step-down modules from the main line of the electric vehicle have been optimized and removed. The two step-down modules draw power directly from the circuit breaker. The first cable 64 is at the input end and is not controlled by the circuit breaker's on / off state, ensuring uninterrupted power supply. The second cable 65 is at the output end of the circuit breaker and is controlled by the circuit breaker's on / off state. At the same time, the output cables of the first step-down module 62 and the second step-down module 63 are both connected to the electric vehicle and the electrical load through the step-down output port 66 on one side, which greatly simplifies the cabling and significantly improves the power safety of the main cable.

[0040] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. An air switch for an integrated DC converter for electric vehicles, comprising a circuit breaker (1), wherein the circuit breaker (1) is provided with a contact mechanism (2), an arc extinguishing mechanism (3), a linkage device (4), and a tripping mechanism (5), characterized in that: The circuit breaker (1) is also equipped with a voltage conversion unit (6), which includes a flame-retardant housing (61) and a first step-down module (62) and a second step-down module (63) built therein. The first step-down module (62) is connected to the input voltage terminal of the circuit breaker (1), and the second step-down module (63) is connected to the output voltage terminal of the circuit breaker (1). The voltage output terminal of the first step-down module (62) is connected to the central control and cloud upload module. The input voltage of the first step-down module (62) is 48-60V, and its output voltage is 5-6V. The voltage output terminal of the second step-down module (63) is connected to other on-board electrical components of the electric vehicle. The input voltage of the second step-down module (63) is 48-60V, and its output voltage is 12V. The contact mechanism (2) includes an input contact (21) and an output contact (22). The input contact (21) is used to input voltage, and the output contact (22) is used to control the connection and disconnection of the load.

2. The air switch for an integrated DC converter for an electric vehicle as described in claim 1, characterized in that: The arc extinguishing mechanism (3) is an arc extinguishing cover, which is composed of multiple insulating metal plates arranged together. It is located on one side of the contact point between the end of the connecting rod device (4) and the input voltage contact point of the contact mechanism (2), and is used to guide and extinguish the sparks generated at the moment the contact point is disconnected.

3. The air switch for an integrated DC converter for an electric vehicle as described in claim 2, characterized in that: The linkage device (4) includes an operating handle (41) on top of the circuit breaker (1) and a movable contact (42) controlled by the operating handle (41) to open and close. The movable contact (42) is normally connected to the tripping mechanism (5) so that current from the input contact (21) flows through the output contact (22) to the load.

4. The air switch for an integrated DC converter for an electric vehicle as described in claim 3, characterized in that: The tripping mechanism (5) includes an electromagnetic tripping assembly (51) and a thermal tripping assembly (52).

5. The air switch for an integrated DC converter for an electric vehicle as described in claim 4, characterized in that: The electromagnetic tripping assembly (51) is an electromagnetic coil, and the thermal tripping assembly (52) is a bimetallic strip composed of two different metals. Under normal conditions, the current flows from the input contact through the electromagnetic coil and then through the bimetallic strip to the load.

Images