A waterproof circuit system for switches used in electric vehicles

Abstract

The present invention provides a switch waterproof circuit system for electric vehicles, wherein an MCU module, a signal processing module, and a drive module are configured on an instrument circuit board, wherein the signal input end of the signal processing module is connected to a switch assembly, and the signal output end of the signal processing module is connected to the MCU module; the input end of the drive module is connected to the MCU module, and the output end of the drive module is connected to a turn signal assembly. The switch waterproof circuit system for electric vehicles described in the present invention integrates the signal processing module and the drive module on the instrument circuit board, and realizes the waterproof function and signal acquisition function of the key by recognizing the switch key signal through the MCU module, and at the same time controls the drive circuit to realize the flashing and lighting function of the left and right turn signal indicators.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicle manufacturing, and in particular relates to a waterproof circuit system for a switch used in an electric vehicle. Background Art

[0002] Electric vehicles are becoming more and more popular in short-distance usage scenarios as a very convenient green and environmentally friendly product that uses new energy. Electric vehicles are easily affected by moisture, rain and other environments, and switch buttons often malfunction or fail, causing electric vehicle safety accidents and poor user experience.

[0003] At present, most switches and button controls use the power input switch method of directly controlling the power-consuming equipment, such as Figure 1 As shown in the figure, one end of the switch button is connected to the power supply end, and the other end is connected to the power supply end of the load. The power supply of the electrical equipment adopts a battery power supply (mostly 48V / 60V / 72V), which causes the key switch to have a large voltage difference between closing and breaking, and a large startup instantaneous and breaking current. The performance requirements of the key switch are improved, but the development trend of actual applications is the miniaturization of the keys, which greatly increases the difficulty of design; the actual application scenario may have a humid environment or even rain, which is prone to lamp bead flickering or even switch failure. Therefore, the switch button needs to have a waterproof function, but most designs do not have waterproof capabilities, the waterproof function is unreliable and the cost is high, resulting in lamp bead flickering or even switch failure in a humid environment or after rain. Figure 2 The instrument shown collects the on and off signal of the turn signal, and displays the indicator light status on the instrument at the same frequency. The non-waterproof switch button brings a very poor experience to the user and even causes economic losses and safety accidents; at the same time, the connection wiring harness of the button switch is complicated, resulting in increased costs and complicated installation; therefore, there is an urgent need for a waterproof circuit system for switches for electric vehicles. Summary of the invention

[0004] In view of this, the present invention aims to provide a waterproof switch circuit system for an electric vehicle to solve the problem that the switch button of the electric vehicle is not waterproof, causing the lamp beads to flicker or even the switch button to fail when the electric vehicle is in a humid environment or after rain.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A waterproof circuit system for a switch used in an electric vehicle comprises an instrument circuit board, on which an MCU module, a signal processing module and a drive module are arranged, wherein a signal input end of the signal processing module is connected to a switch assembly, and a signal output end of the signal processing module is connected to the MCU module;

[0007] The input end of the driving module is connected to the MCU module, and the output end of the driving module is connected to the turn signal assembly.

[0008] Furthermore, a DC-DC module is also configured on the instrument circuit board, the OUT+ end of the DC-DC module is connected to the VCC end of the MCU, the IN+ end of the DC-DC module is connected to the cathode end of the diode D11, the anode end of the diode D11 is connected to the key switch, and the other end of the key switch is connected to the power module through the fuse F5;

[0009] The OUT- terminal of the DC-DC module is connected to the VCC terminal of the MCU through the capacitor C3, and the OUT- terminal of the DC-DC module is grounded.

[0010] Further, the driving module includes a resistor R52, one end of the resistor R52 is connected to the IO_1 terminal of the MCU, the other end of the resistor R52 is respectively connected to the anode end of the resistor R50 and the diode D4, one end of the resistor R50 is connected to the VCC terminal, and the cathode end of the diode D4 is connected to the switch component;

[0011] It also includes a resistor R55, one end of which is connected to the IO_2 end of the MCU, and the other end of the resistor R55 is respectively connected to the anode end of the resistor R51 and the diode D5. One end of the resistor R51 is connected to the VCC end, and the cathode end of the diode D5 is also connected to the switch component.

[0012] Further, the switch assembly includes a double flash switch S24 and a left / right turn switch S25, the 2 terminal of the double flash switch S24 is connected to the cathode end of the diode D4, the 3 terminal of the double flash switch S24 is connected to the cathode end of the diode D5, and the 0 terminal of the double flash switch S24 is grounded;

[0013] The 1 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D4, the 3 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D5, and the 0 terminal of the left / right turn switch S25 is grounded.

[0014] Furthermore, a capacitor C1 is connected between the resistor R50 and the diode D4 , and a capacitor C2 is connected between the resistor R51 and the diode D5 . The other ends of the capacitors C1 and C2 are both grounded.

[0015] Further, the driving module includes a driving unit 1 and a driving unit 2, the driving module includes a driving unit 1 and a driving unit 2, and the turn signal assembly includes a left turn signal DS17 and a right turn signal DS18;

[0016] One end of the drive unit 1 is connected to the IO_5 end of the MCU module, and the other end of the drive unit 1 is connected to the left turn signal DS17;

[0017] One end of the drive unit 2 is connected to the IO_6 end of the MCU module, and the other end of the drive unit 2 is connected to the right turn signal DS18.

[0018] Further, the driving unit 1 includes a transistor Q16, the base terminal of the transistor Q16 is connected to the IO_5 terminal of the MCU module through a resistor R58 and is grounded through a resistor R60, the emitter terminal of the transistor Q16 is grounded, and the collector terminal of the transistor Q16 is connected to the base terminal of the transistor Q3 through a resistor R56;

[0019] The base terminal of the transistor Q3 is connected to the emitter terminal of the transistor Q3 through the resistor R53, the collector terminal of the transistor Q3 is connected to the left turn signal lamp DS17, and the other end of the left turn signal lamp DS17 is grounded.

[0020] Further, the second driving unit includes a transistor Q15, the base terminal of the transistor Q15 is connected to the IO_6 terminal of the MCU module through a resistor R59 and is grounded through a resistor R61, the emitter terminal of the transistor Q15 is grounded, and the collector terminal of the transistor Q15 is connected to the base terminal of the transistor Q1 through a resistor R57;

[0021] The base terminal of the transistor Q1 is connected to the emitter terminal of the transistor Q1 through the resistor R54, the collector terminal of the transistor Q1 is connected to the right turn signal lamp DS18, and the other end of the right turn signal lamp DS18 is grounded.

[0022] Compared with the prior art, the waterproof circuit system for a switch for an electric vehicle described in the present invention has the following beneficial effects:

[0023] (1) The waterproof switch circuit system for electric vehicles described in the present invention integrates a signal processing module and a driving module into an instrument circuit board. The switch on / off signal is transmitted to the MCU module of the instrument through the signal processing module for collection. The MCU module controls the driving module to directly drive the left and right turn signals to realize the flashing lighting functions such as left and right turn signals. Without increasing the complexity of the connection lines, the instrument connection terminals can achieve unified control of the switch buttons and corresponding components.

[0024] (2) The waterproof circuit system for electric vehicle switches described in the present invention integrates the signal processing module and the drive module into the instrument circuit board, thereby avoiding the cost and installation difficulty of making a separate waterproof circuit board or adding waterproof hardware to each electrical component. It does not need to modify the original lamps and replace the flashers, thus realizing unified control of the instrument and unified connection of the wiring harness, which is conducive to the optimized layout of the wiring harness.

[0025] (3) The waterproof circuit system of a switch for an electric vehicle described in the present invention has a simple structure, good on-site use effect, saves processing and manufacturing costs, and is easy to promote on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings constituting 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 an improper limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 This is the original electric vehicle steering switch control circuit diagram according to the embodiment of the present invention;

[0028] Figure 2 The original instrument signal acquisition circuit diagram described in the embodiment of the present invention;

[0029] Figure 3 A circuit diagram of a waterproof circuit system for a switch for an electric vehicle according to an embodiment of the present invention;

[0030] Figure 4 This is an equivalent circuit diagram of the switch water immersion test described in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0034] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0035] See also Figure 3 As shown, a waterproof circuit system for a switch used in an electric vehicle, an MCU module, a signal processing module, and a drive module are configured on the instrument circuit board, the signal input end of the signal processing module is connected to the switch component, and the signal output end of the signal processing module is connected to the MCU module;

[0036] The input end of the driving module is connected to the MCU module, and the output end of the driving module is connected to the turn signal assembly.

[0037] The instrument circuit board is also equipped with a DC-DC module, the OUT+ end of the DC-DC module is connected to the VCC end of the MCU, the IN+ end of the DC-DC module is connected to the cathode end of the diode D11, the anode end of the diode D11 is connected to the key switch, the diode D11 is an anti-reverse diode, which prevents the circuit from being damaged due to reverse connection of the power supply, the other end of the key switch is connected to the positive end of the power module through the fuse F5, and the negative end of the power module is grounded. The voltage range of the power module used in this technical solution is 36V-72V. The DC-DC module converts the power supply to output 5V or 3.3V VCC power supply to the instrument microcontroller and peripheral hardware in the full range of operation, and the fuse F5 plays the role of overcurrent protection and short circuit protection;

[0038] The OUT- terminal of the DC-DC module is connected to the VCC terminal of the MCU through the capacitor C3, the OUT- terminal of the DC-DC module is grounded, and the IN- terminal of the DC-DC module is grounded.

[0039] The driving module includes a resistor R52, one end of which is connected to the IO_1 terminal of the MCU, the other end of which is connected to the anode end of the resistor R50 and the diode D4 respectively, one end of the resistor R50 is connected to the VCC terminal, and the cathode end of the diode D4 is connected to the switch component;

[0040] It also includes a resistor R55, one end of which is connected to the IO_2 end of the MCU, and the other end of the resistor R55 is respectively connected to the anode end of the resistor R51 and the diode D5, one end of the resistor R51 is connected to the VCC end, and the cathode end of the diode D5 is also connected to the switch component. The resistance range of the resistors R50 and R51 used in this technical solution is 500Ω-2.2kΩ, and the resistance range of the resistors R52 and R55 is 1kΩ-10kΩ; when the VCC voltage value is 5V, the diodes D4 and D5 use the switching diode 4148 with a withstand voltage of 100V, and when the VCC voltage value is 3.3V, the diodes D4 and D5 use the durable 100V germanium diode BAT46W. The diodes D4 and D5 mainly prevent abnormal levels (such as: battery power +) from connecting to the signal port to damage the instrument MCU, which can effectively prevent the entire vehicle from damaging the instrument when an unexpected situation occurs in the connection harness and the terminal block;

[0041] The instrument MCU detects the level between the pull-up resistor and the diode through resistors R52 and R55, which correspond to the left turn switch signal and the right turn switch signal respectively. When the switch is not pressed, the VCC level is high. When the switch is pressed, the corresponding switch is closed and grounded, which is a low level (VCC is 5V, corresponding to a voltage drop of about 0.7V for 4148, and VCC is 3.3V, corresponding to a voltage drop of about 0.3V for BAT46W), which can accurately identify the switch signal.

[0042] The switch assembly includes a double flash switch S24 and a left / right turn switch S25, wherein the 2 terminal of the double flash switch S24 is connected to the cathode end of the diode D4, the 3 terminal of the double flash switch S24 is connected to the cathode end of the diode D5, and the 0 terminal of the double flash switch S24 is grounded;

[0043] The 1 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D4, the 3 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D5, and the 0 terminal of the left / right turn switch S25 is grounded.

[0044] A capacitor C1 is connected between the resistor R50 and the diode D4, and a capacitor C2 is connected between the resistor R51 and the diode D5. The other ends of the capacitors C1 and C2 are grounded. The capacitors C1 and C2 used in this technical solution are hardware anti-shake capacitors to prevent high-frequency switch change signals from appearing at the moment of contact. The capacitors can effectively suppress high-frequency signals and play a role in smoothing signals, thereby reducing the jitter signals of the switches from the hardware perspective.

[0045] The driving module includes a driving unit 1 and a driving unit 2, the driving module includes a driving unit 1 and a driving unit 2, and the turn signal lamp assembly includes a left turn signal lamp DS17 and a right turn signal lamp DS18;

[0046] One end of the drive unit 1 is connected to the IO_5 end of the MCU module, and the other end of the drive unit 1 is connected to the left turn signal DS17;

[0047] One end of the drive unit 2 is connected to the IO_6 end of the MCU module, and the other end of the drive unit 2 is connected to the right turn signal DS18.

[0048] The driving unit 1 includes a transistor Q16, the base terminal of the transistor Q16 is connected to the IO_5 terminal of the MCU module through a resistor R58 and is grounded through a resistor R60, the emitter terminal of the transistor Q16 is grounded, and the collector terminal of the transistor Q16 is connected to the base terminal of the transistor Q3 through a resistor R56;

[0049] The base terminal of the transistor Q3 is connected to the emitter terminal of the transistor Q3 through the resistor R53, the collector terminal of the transistor Q3 is connected to the left turn signal lamp DS17, and the other end of the left turn signal lamp DS17 is grounded.

[0050] The second driving unit includes a transistor Q15, the base terminal of the transistor Q15 is connected to the IO_6 terminal of the MCU module through a resistor R59 and is grounded through a resistor R61, the emitter terminal of the transistor Q15 is grounded, and the collector terminal of the transistor Q15 is connected to the base terminal of the transistor Q1 through a resistor R57;

[0051] The base terminal of the transistor Q1 is connected to the emitter terminal of the transistor Q1 through the resistor R54, the collector terminal of the transistor Q1 is connected to the right turn signal lamp DS18, and the other end of the right turn signal lamp DS18 is grounded.

[0052] When this solution is implemented, the instrument MCU collects left and right turn signals between resistor R50 and diode D4 and between resistor R51 and diode D5 through resistors R52 and R55. The high level indicates the switch is disconnected and the low level indicates the switch is closed. The double flash switch S24 is a single-open dual-control button, and the self-locking switch S25 is a single-channel three-speed switch. When S25 is connected to the 0-1 pin, the left turn switch is turned on. When S25 is connected to the 0-3 pin, the right turn switch is turned on. When the 0-2 terminal is connected, neither the left nor the right turn switch is turned on. When the S24 switch is closed, the left and right turn switches are turned on at the same time and the S25 switch is invalid at this time. The signals collected by the IO_1 and IO_2 terminals of the instrument MCU, IO_5 and IO_6 correspondingly send out a 1Hz PWM wave to control the transistor Q1 through the current limiting resistors R58 and R59. 6. Q15, when the left turn signal at the IO_1 end is at a low level, the IO_5 end sends out a 1Hz PWM wave through the current limiting resistor R58 to reach the base of the transistor Q16. R60 is a pull-down resistor at the base (to prevent the IO port level uncertainty interference signal from accidentally triggering the transistor Q16 when the instrument MCU is powered on and initialized) to prevent it from opening. When the IO_5 end is at a high level, the transistor Q16 is saturated and turned on. At this time, the resistors R53 and R56 are connected to the base of Q3 after voltage division. The transistor Q3 is saturated and turned on, and the BAT+ power supply is connected to the left Turn signal, the left turn signal is on. When the IO_5 terminal is at a low level, transistors Q16 and Q3 are cut off, and the left turn signal is off, completing the amplification and driving function of the control signal. When a 1Hz PWM wave is emitted at the IO_5 terminal, the left turn signal will flash at the same frequency. Similarly, when the right turn signal at the IO_2 terminal is at a low level, a 1Hz PWM wave is emitted at the IO_6 terminal, reaching the base of transistor Q15 through the current limiting resistor R59. R61 is a pull-down resistor for the base. When the IO_6 terminal is at a high level, transistor Q15 is saturated. When the IO_6 terminal is at a low level, transistors Q15 and Q1 are cut off, and the right turn light is off, completing the amplification and driving function of the control signal. When a 1Hz PWM wave is emitted at the IO_6 terminal, the right turn light will flash at the same frequency. When the double flash switch S24 is turned on, the IO_5 terminal and the IO_6 terminal emit PWM waves of the same frequency, and at the same time, the flashing of the left and right turn lights is controlled.

[0053] like Figure 4As shown, through the water-immersed experiment of the key switch, it is found that the corresponding equivalent resistance when the switch is disconnected is between 4.7kΩ and 47kΩ. According to the worst case, the pull-up resistor R50 is 2.2kΩ, and the minimum equivalent resistance S25-R of the switch S25 is 4.7kΩ. The voltage collected by the instrument MUC through the resistor R52 when immersed in water is calculated. When the VCC voltage value is 5V, the voltage drop of diode D4 is 0.7V, and the voltage collected by the instrument MCU through the current limiting resistor R52 is 3.63V. When VCC is 3.3V, the voltage drop of diode D4 is 0.3V, and the voltage collected by the instrument MCU through the current limiting resistor R52 is 2.34V. In both cases, it is greater than the corresponding MCU high-level recognition range (0.7*VCC). At the same time, diode D4 can provide effective protection for the signal acquisition circuit due to input signal errors (such as connecting to a 48V high level). Capacitor C1 can reduce and prevent the signal jitter problem of the switch button at the moment of connection, ensuring the credibility and reliability of the signal. Equivalent circuit analysis and practical verification have proved that the signal acquisition can effectively realize the waterproof function of the key switch.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A waterproof circuit system for a switch used in an electric vehicle, comprising an instrument circuit board, Features: The instrument circuit board is equipped with an MCU module, a signal processing module, and a drive module. The signal input end of the signal processing module is connected to the switch component, and the signal output end of the signal processing module is connected to the MCU module. The input end of the driving module is connected to the MCU module, and the output end of the driving module is connected to the turn signal assembly; The driving module includes a resistor R52, one end of which is connected to the IO_1 terminal of the MCU, the other end of which is connected to the anode end of the resistor R50 and the diode D4 respectively, one end of the resistor R50 is connected to the VCC terminal, and the cathode end of the diode D4 is connected to the switch component; It also includes a resistor R55, one end of which is connected to the IO_2 terminal of the MCU, and the other end of which is connected to the anode end of the resistor R51 and the diode D5 respectively, one end of the resistor R51 is connected to the VCC terminal, and the cathode end of the diode D5 is also connected to the switch component; The driving module includes a driving unit 1 and a driving unit 2, and the turn signal lamp assembly includes a left turn signal lamp DS17 and a right turn signal lamp DS18; One end of the drive unit 1 is connected to the IO_5 end of the MCU module, and the other end of the drive unit 1 is connected to the left turn signal DS17; One end of the drive unit 2 is connected to the IO_6 end of the MCU module, and the other end of the drive unit 2 is connected to the right turn signal DS18; The driving unit 1 includes a transistor Q16, the base terminal of the transistor Q16 is connected to the IO_5 terminal of the MCU module through a resistor R58 and is grounded through a resistor R60, the emitter terminal of the transistor Q16 is grounded, and the collector terminal of the transistor Q16 is connected to the base terminal of the transistor Q3 through a resistor R56; The base terminal of the transistor Q3 is connected to the emitter terminal of the transistor Q3 through the resistor R53, the collector terminal of the transistor Q3 is connected to the left turn signal lamp DS17, and the other end of the left turn signal lamp DS17 is grounded; The second driving unit includes a transistor Q15, the base terminal of the transistor Q15 is connected to the IO_6 terminal of the MCU module through a resistor R59 and is grounded through a resistor R61, the emitter terminal of the transistor Q15 is grounded, and the collector terminal of the transistor Q15 is connected to the base terminal of the transistor Q1 through a resistor R57; The base terminal of the transistor Q1 is connected to the emitter terminal of the transistor Q1 through the resistor R54, the collector terminal of the transistor Q1 is connected to the right turn signal lamp DS18, and the other end of the right turn signal lamp DS18 is grounded.

2. A waterproof circuit system for a switch for an electric vehicle according to claim 1, Features: The instrument circuit board is also equipped with a DC-DC module, the OUT+ end of the DC-DC module is connected to the VCC end of the MCU, the IN+ end of the DC-DC module is connected to the cathode end of the diode D11, the anode end of the diode D11 is connected to the key switch, and the other end of the key switch is connected to the power module through the fuse F5; The OUT- terminal of the DC-DC module is connected to the VCC terminal of the MCU through the capacitor C3, and the OUT- terminal of the DC-DC module is grounded.

3. A waterproof circuit system for a switch for an electric vehicle according to claim 1, Features: The switch assembly includes a double flash switch S24 and a left / right turn switch S25, wherein the 2 terminal of the double flash switch S24 is connected to the cathode end of the diode D4, the 3 terminal of the double flash switch S24 is connected to the cathode end of the diode D5, and the 0 terminal of the double flash switch S24 is grounded; The 1 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D4, the 3 terminal of the left / right turn switch S25 is connected to the cathode terminal of the diode D5, and the 0 terminal of the left / right turn switch S25 is grounded.

4. A waterproof circuit system for a switch for an electric vehicle according to claim 1, Features: A capacitor C1 is connected between the resistor R50 and the diode D4 , and a capacitor C2 is connected between the resistor R51 and the diode D5 . The other ends of the capacitors C1 and C2 are both grounded.

Images