Speed adaptive LED brightness control circuit for a cycling vehicle

Abstract

The utility model relates to the field of LED control technology discloses a kind of high reliability and stable speed adaptive LED brightness control circuit of riding vehicle, including the Hall sensor (120) for detecting the speed sensing signal output when the wheel rotates, main control module (130) and switch module (140), wherein, the duty cycle of PWM dimming signal is adjusted according to the speed sensing signal feedback, to adjust the luminous brightness of LED module by main control module (130).

Description

Technical Field

[0001] This utility model relates to the field of LED control technology, and more specifically, to a speed-adaptive LED brightness control circuit for bicycles. Background Technology

[0002] Currently, most cycling vehicles (such as bicycles and electric bicycles) are equipped with LED lighting devices to improve visibility and safety at night or in low-light environments. However, most existing LED lighting devices have a fixed brightness and cannot automatically adjust the brightness according to the riding speed. This means that at high speeds, the fixed brightness may not provide sufficient visibility, posing a safety hazard; while at low speeds or when stationary, excessively bright lighting results in unnecessary energy waste and shortens battery life.

[0003] Although there are some LED bicycle lights on the market with dimming functions, most of them rely on manual switching or ambient light sensing and fail to link with riding speed, thus failing to achieve intelligent, energy-saving, and safe adaptive lighting effects.

[0004] Therefore, it is necessary to propose a control circuit that can automatically adjust the LED brightness according to the riding speed to solve the above problems. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a speed-adaptive LED brightness control circuit for bicycles that is more reliable and stable, addressing the shortcomings of existing LED bicycle lights with dimming functions, which mostly rely on manual switching or ambient light sensing and fail to be linked with riding speed.

[0006] The technical solution adopted by this utility model to solve its technical problem is: to construct a speed-adaptive LED brightness control circuit for a bicycle, comprising: A Hall sensor, which is mounted on the wheel, is used to detect the speed sensing signal output when the wheel rotates; The main control module has its signal input terminal coupled to the output terminal of the Hall sensor, and is used to receive the speed sensing signal and output the PWM dimming signal; The switching module has its first terminal connected to the signal output terminal of the main control module for receiving the PWM dimming signal. The second terminal of the switch module is connected to the positive terminal of the LED module. The third terminal of the switch module is connected to the common terminal; The main control module adjusts the duty cycle of the PWM dimming signal based on the feedback speed sensing signal to adjust the brightness of the LED module.

[0007] In some embodiments, the Hall sensor is mounted on the wheel in conjunction with a magnet to detect the speed sensing signal generated when the wheel rotates.

[0008] In some implementations, the output of the Hall sensor is connected to the signal input of the main control module via a first resistor.

[0009] In some implementations, the main control module includes a main controller. The signal input terminal of the main controller is coupled to the output terminal of the Hall sensor, and is used to receive the speed sensing signal and adjust the duty cycle of the PWM dimming signal according to the speed sensing signal. The output terminal of the main controller is connected to the first terminal of the switch module.

[0010] In some embodiments, the switching module includes a first MOSFET. The gate of the first MOSFET is connected to the signal output terminal of the main controller via a fourth resistor, for receiving the PWM dimming signal. The drain of the first MOSFET is connected to the positive terminal of the LED module. The source of the first MOSFET is connected to the common terminal.

[0011] In some implementations, the first MOSFET is selected as an N-channel enhancement-mode MOSFET.

[0012] In some implementations, the duty cycle of the PWM dimming signal is adjustable in 100 levels from 0% to 100%.

[0013] In some implementations, the LED module's default start-up brightness is 50%.

[0014] The speed-adaptive LED brightness control circuit for bicycles described in this invention includes a Hall sensor for detecting the speed sensing signal output when the wheel rotates, a main control module, and a switching module. The main control module adjusts the duty cycle of the PWM dimming signal based on the feedback speed sensing signal to regulate the brightness of the LED module. Compared to existing technologies, by working collaboratively with the Hall sensor and the main control module, real-time and automatic linkage between LED module brightness and riding speed is achieved. Brightness is automatically increased during high-speed riding to ensure clear visibility and effectively reduce the risk of accidents due to insufficient lighting; brightness is automatically reduced during low-speed riding or when stopped to avoid glare to pedestrians or oncoming vehicles, thus achieving a two-way safety improvement. On the other hand, users do not need to operate the LED module at all. The LED module can automatically adjust to the most suitable brightness according to the riding status. This "seamless" intelligent interaction saves users the trouble of manually switching and provides a smoother and more focused riding experience. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This utility model provides a circuit diagram of an embodiment of a speed-adaptive LED brightness control circuit for bicycles. Detailed Implementation

[0016] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0017] like Figure 1 As shown, in the first embodiment of the speed-adaptive LED brightness control circuit for bicycles of this utility model, the speed-adaptive LED brightness control circuit 100 for bicycles includes a first power module 110, a Hall sensor 120, a main control module 130, a switch module 140, and a second power module 150. The first power module 110 is used to receive the voltage (e.g., 3.7V) input from the battery pack, regulate / filter the input voltage (e.g., 3.7V), and provide working power to the Hall sensor 120 and the main control module 130. The Hall sensor 120 is used to detect the speed sensing signal output when the wheel 200 rotates and feeds it back to the main control module 130; The main control module 130 has the functions of logic operation, speed sensing signal reception and analysis, outputting at least one PWM dimming signal and adjusting the duty cycle of the PWM dimming signal; Switch module 140 functions as a switch; The second power module 150 is used to receive the voltage input from the battery pack (e.g., 3.7V), filter the input voltage (e.g., 3.7V), and provide operating power to the LED module; Specifically, the Hall sensor 120 is installed on the wheel 200 to detect the speed sensing signal output by the rotation of the wheel 200 when the vehicle is being ridden, and outputs the speed sensing signal to the main control module 130. Furthermore, the signal input terminal of the main control module 130 is coupled to the output terminal of the Hall sensor 120, and is used to receive the speed sensing signal input by the Hall sensor 120, and output a PWM dimming signal according to the input speed sensing signal. Furthermore, the first end of the switch module 140 is connected to the signal output end of the main control module 130 to receive PWM dimming signals. The input PWM dimming signals are used to control the working state of the switch module 140. The second terminal of the switch module 140 is connected to the positive terminal of the LED module (corresponding to LED1), and the negative terminal of the LED module (corresponding to LED1) is connected to the output terminal of the second power module 150 to provide driving power to the LED module (corresponding to LED1). The third terminal of switch module 140 is connected to the common terminal; The main control module 130 can adjust the duty cycle of the PWM dimming signal according to the feedback speed sensing signal to adjust the brightness of the LED module (corresponding to LED1).

[0018] Using this technical solution, the Hall sensor works in conjunction with the main control module to achieve real-time and automatic linkage between LED module brightness and riding speed. When riding at high speed, the brightness is automatically increased to ensure clear vision and effectively reduce the risk of accidents caused by insufficient lighting; when riding at low speed or when stopped, the brightness is automatically reduced to avoid glare to pedestrians or oncoming vehicles, thus achieving a two-way safety improvement. On the other hand, users do not need to operate the LED module at all. The LED module can automatically adjust to the most suitable brightness according to the riding status. This "seamless" intelligent interaction saves users the trouble of manually switching and provides a smoother and more focused riding experience.

[0019] In some implementations, such as Figure 1 As shown, the Hall sensor 120 is installed at the wheel 200 in conjunction with a magnet to detect the speed sensing signal generated when the wheel 200 rotates, and outputs the speed sensing signal to the main control module 130.

[0020] In some implementations, such as Figure 1 As shown, the output terminal of the Hall sensor 120 is connected to the signal input terminal of the main control module 130 through the first resistor R101, and the speed sensing signal is input to the main control module 130.

[0021] In some implementations, such as Figure 1 As shown, the main control module 130 includes a main controller MCU, which has the functions of logic operation, speed sensing signal reception and analysis, outputting at least one PWM dimming signal and adjusting the duty cycle of the PWM dimming signal; Specifically, the signal input terminal (pin 2) of the main controller MCU is connected to the output terminal (pin 3) of the Hall sensor 120 to receive the speed sensing signal input from the Hall sensor 120 and adjust the duty cycle of the PWM dimming signal according to the speed sensing signal. The Hall sensor 120 is installed near the wheel 200, and a magnet is fixed on the wheel 200. For every rotation of wheel 200, Hall sensor 120 senses the magnet once and outputs a pulse signal to the Speed_Dect pin (corresponding to HSIN) of the main controller MCU. The main controller MCU calculates the number of pulses per unit time and combines this with the 200 circumference of the wheel to calculate the real-time riding speed and corresponding PWM dimming signal. The output terminal (corresponding to pin 3) of the main controller MCU is connected to the first terminal of the switch module 140, and the PWM dimming signal is input to the first terminal of the switch module 140 to control its on / off state; The main controller MCU determines the current speed range based on the received speed sensing signal through its internal program and outputs a PWM dimming signal with a corresponding duty cycle. For example, the higher the speed, the larger the PWM duty cycle, and the higher the LED brightness; The lower the speed, the smaller the duty cycle, and the lower the brightness.

[0022] In some embodiments, the switching module 140 includes a first MOSFET Q101, which is selected as an N-channel enhancement-mode MOSFET and has the function of switching; Specifically, the gate of the first MOSFET Q101 is connected to the signal output terminal (pin 3) of the main controller MCU through the fourth resistor R104, and is used to receive PWM dimming signals. The drain of the first MOSFET Q101 is connected to the positive terminal of the LED module. The source of the first MOSFET Q101 is connected to the common terminal through the third resistor R103; Specifically, the PWM dimming signal drives the gate of the first MOSFET Q101 through the fourth resistor R104 and the fifth resistor R105, controlling the on and off time of LED1. The brightness of LED1 is determined by the duty cycle of the PWM dimming signal, enabling stepless or stepped dimming. The duty cycle of the PWM dimming signal is adjustable in 100 levels from 0% to 100%.

[0023] The default starting brightness of the LED module is 50%.

[0024] In some embodiments, the first power module 110 includes at least a first diode D101 and a voltage regulator chip U101, wherein the anode of the first diode D101 is connected to one end of the battery pack (BAT), the cathode of the first diode D101 is connected to the input terminal of the voltage regulator chip U101, and the output terminal of the voltage regulator chip U101 is connected to the power input terminal of the main controller MCU. That is, it is powered by a 3.7V battery pack (BAT), and a stable 3.3V or 5V voltage is provided to the main controller MCU and other logic circuits through the first diode D101 (reverse polarity protection diode) and the voltage regulator chip U101.

[0025] In some embodiments, the second power module 150 includes at least a first capacitor C101 and a second capacitor C102 connected in parallel. One end of the battery pack (BAT) is connected to one end of a second resistor R102 through one end of the first capacitor C101 and one end of the second capacitor C102, and the other end of the second resistor R102 is connected to the negative terminal of the LED module (corresponding to LED1). Among them, the second resistor R102 is a current-limiting resistor, and the third resistor R103 is used for current sampling or protection.

[0026] Specifically: LED1 (White Lamp) uses high-power white LEDs (or LEDs of different color temperatures, depending on the application scenario) to provide lighting source output. It is controlled by the PWM_LED signal (corresponding to the PWM dimming signal) output by the main controller MCU. The PWM duty cycle has 100 levels, that is, 0-100% dimming. The driving speed detection circuit consists of a Hall sensor H101 and the Speed_Dect or HSIN pin of the main controller MCU. The driving speed can be calculated by multiplying the number of times the Hall sensor detects the speed by 200 circumferences of the wheel per unit time. The speed is transmitted to the main controller MCU for analysis through the Speed_Dect pin (corresponding to HSIN). The MCU outputs a PWM_LED signal (corresponding to a PWM dimming signal) according to the speed signal. When LED1 (White Lamp) is started normally, the default brightness is 50%. At this time, Hall sensor H101 will identify the driving speed signal and transmit it to the main controller MCU. The main controller MCU can analyze and process the identified sensing signal and control the dimming ratio of the first MOSFET Q101 through the PWM_LED pin, so that the faster the driving speed, the higher the LED brightness and the slower the speed, the lower the LED brightness.

[0027] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A speed-adaptive LED brightness control circuit for a bicycle, characterized in that, have: A Hall sensor, which is mounted on the wheel, is used to detect the speed sensing signal output when the wheel rotates; The main control module has its signal input terminal coupled to the output terminal of the Hall sensor, and is used to receive the speed sensing signal and output the PWM dimming signal; The switching module has its first terminal connected to the signal output terminal of the main control module for receiving the PWM dimming signal. The second terminal of the switch module is connected to the positive terminal of the LED module. The third terminal of the switch module is connected to the common terminal; The main control module adjusts the duty cycle of the PWM dimming signal based on the feedback speed sensing signal to adjust the brightness of the LED module.

2. The speed-adaptive LED brightness control circuit for bicycles according to claim 1, characterized in that, The Hall sensor, in conjunction with a magnet, is installed at the wheel to detect the speed sensing signal generated when the wheel rotates.

3. The speed-adaptive LED brightness control circuit for bicycles according to claim 1 or 2, characterized in that, The output terminal of the Hall sensor is connected to the signal input terminal of the main control module through a first resistor.

4. The speed-adaptive LED brightness control circuit for bicycles according to claim 1, characterized in that, The main control module includes a main controller. The signal input terminal of the main controller is coupled to the output terminal of the Hall sensor, and is used to receive the speed sensing signal and adjust the duty cycle of the PWM dimming signal according to the speed sensing signal. The output terminal of the main controller is connected to the first terminal of the switch module.

5. The speed-adaptive LED brightness control circuit for bicycles according to claim 4, characterized in that, The switching module includes a first MOSFET. The gate of the first MOSFET is connected to the signal output terminal of the main controller via a fourth resistor, for receiving the PWM dimming signal. The drain of the first MOSFET is connected to the positive terminal of the LED module. The source of the first MOSFET is connected to the common terminal.

6. The speed-adaptive LED brightness control circuit for a bicycle according to claim 5, characterized in that, The first MOSFET is selected as an N-channel enhancement-mode MOSFET.

7. The speed-adaptive LED brightness control circuit for a cycling vehicle according to any one of claims 1-5, characterized in that, The duty cycle of the PWM dimming signal is adjustable in 100 levels from 0% to 100%.

8. The speed-adaptive LED brightness control circuit for a cycling vehicle according to any one of claims 1-5, characterized in that, The default starting brightness of the LED module is 50%.

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