Temperature-sensing fire detector with Bluetooth positioning function

Abstract

This utility model discloses a low-power temperature-sensing fire detector with Bluetooth positioning function. The circuit board includes a rectifier bridge, a fire detection chip, an NTC thermistor, a Bluetooth chip, a power supply chip, a voltage converter, and an LED indicator. The circuit board is connected to the fire protection bus via terminals. The bus is connected to the fire detection chip via the rectifier bridge. The fire detection chip is connected to the power supply chip, NTC thermistor, voltage converter, and LED indicator via pins. The fire detection chip is connected to the Bluetooth chip via the voltage converter, and the Bluetooth chip is connected to a crystal via pins. By setting up the rectifier bridge, fire detection chip, NTC thermistor, Bluetooth chip, power supply chip, voltage converter, and LED indicator, not only can fire detection be achieved by monitoring ambient temperature, but it can also perform Bluetooth positioning of trapped personnel and firefighters in a fire with extremely low power consumption. The positioning accuracy is high and the speed is fast, and the impact on the existing fire protection system is minimal.

Description

Technical Field

[0001] This utility model relates to the field of fire detector technology, specifically a heat-sensing fire detector with Bluetooth positioning function. Background Technology

[0002] However, emergency fire indicator lights are generally installed in building corridors, covering a relatively small area, while fire detectors are deployed more densely and are also installed inside rooms. Bluetooth Low Energy (BLE) is a mature technology and the lowest power consumption radio frequency technology used for positioning.

[0003] However, existing fire detectors still have some problems: traditional fire detectors lack positioning functions, making it difficult to locate trapped people and firefighters in a fire.

[0004] Therefore, designing a low-power fire detector with Bluetooth positioning function is a reasonable solution for personnel positioning in emergency fire-fighting scenarios. Utility Model Content

[0005] The purpose of this invention is to provide a heat-sensing fire detector with Bluetooth positioning function to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a heat-sensing fire detector with Bluetooth positioning function, comprising a circuit board disposed inside the fire detector. The circuit board includes a rectifier bridge, a fire detection chip, an NTC thermistor, a Bluetooth chip, a power supply chip, a voltage converter, and an LED indicator. The circuit board is connected to a fire alarm bus via terminals. The bus is connected to the fire detection chip CS2132ALO via the rectifier bridge. The fire detection chip CS2132ALO is connected to the NTC thermistor via pins to detect ambient temperature. The fire detection chip CS2132ALO is also connected to the LED indicator via pins to indicate the ambient temperature. In standby mode, the CS2132ALO fire detection chip's internal LDO reduces the 24V bus voltage to 5V and outputs it to the power supply pin. The 5V power supply pin of the CS2132ALO is connected to the power supply chip's input pin, and the 3.3V output pin of the power supply chip is connected to the nRF52805 Bluetooth chip to power it. The nRF52805 Bluetooth chip is connected to the crystal and the antenna via pins. One end of the voltage converter pin is connected to the CS2132ALO fire detection chip, and the other end is connected to the nRF52805 Bluetooth chip, thus establishing the connection between the fire detection chip and the Bluetooth chip.

[0007] Preferably, the fire detection chip CS2132ALO is connected to an NTC thermistor, and the thermistor voltage value is collected periodically by an ADC to complete the ambient temperature detection.

[0008] Preferably, the Bluetooth circuit of the Bluetooth chip nRF52805 uses 32M and 32.768K crystals, and the pins of the crystals are connected to matching capacitors respectively.

[0009] Preferably, the Bluetooth chip nRF52805 pins are connected to the antenna after passing through a filter capacitor and a filter inductor.

[0010] Preferably, the input and output terminals of the power supply pins on the circuit board are filtered out for noise by capacitors.

[0011] Beneficial effects

[0012] This utility model provides a heat-sensing fire detector with Bluetooth positioning function, which has the following advantages:

[0013] This heat-sensing fire detector with Bluetooth positioning function, through the setting of a rectifier bridge, fire detection chip, NTC thermistor, Bluetooth chip, power chip, voltage converter and LED indicator, can not only detect fires by monitoring ambient temperature, but also complete the Bluetooth positioning of trapped people and firefighters in a fire with extremely low power consumption. The positioning accuracy is high and the speed is fast, and the impact on the existing fire protection system is minimal. Attached Figure Description

[0014] Figure 1 This is a block diagram of the overall structure of this utility model;

[0015] Figure 2 This is the circuit diagram for temperature detection and status indication of this utility model;

[0016] Figure 3 This is a power conversion circuit diagram of the present invention;

[0017] Figure 4 This is a circuit diagram of the Bluetooth chip of this utility model;

[0018] Figure 5 This is a circuit diagram of the level conversion and communication interface of this utility model. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] Please see Figure 1-5This utility model provides a technical solution: a temperature-sensing fire detector with Bluetooth positioning function, including a circuit board disposed inside the fire detector. The circuit board includes a rectifier bridge, a fire detection chip, an NTC thermistor, a Bluetooth chip, a power chip, a voltage converter, and an LED indicator. The circuit board is connected to a fire alarm bus via terminals. The bus is connected to the fire detection chip CS2132ALO via the rectifier bridge. The fire detection chip CS2132ALO is connected to the NTC thermistor via pins to detect ambient temperature. The fire detection chip CS2132ALO is also connected to the LED indicator via pins to indicate the device's operating status. The CS2132ALO fire detection chip's internal LDO reduces the 24V bus voltage to 5V and outputs it to the power supply pin. The 5V power supply pin of the CS2132ALO is connected to the power supply chip's input pin, and the 3.3V output pin of the power supply chip is connected to the nRF52805 Bluetooth chip to power it. The nRF52805 Bluetooth chip is connected to the crystal and the antenna via pins. One end of the voltage converter pin is connected to the CS2132ALO fire detection chip, and the other end is connected to the nRF52805 Bluetooth chip, thus realizing the connection between the fire detection chip and the Bluetooth chip.

[0024] The fire detection chip CS2132ALO is connected to an NTC thermistor and uses an ADC to periodically collect the thermistor voltage value to complete the ambient temperature detection.

[0025] The Bluetooth circuit of the nRF52805 Bluetooth chip uses 32M and 32.768K crystals, and the pins of the crystals are connected to matching capacitors respectively.

[0026] The Bluetooth chip nRF52805 pins are connected to the antenna after passing through a filter capacitor and a filter inductor.

[0027] The input and output terminals of the power supply pins on the circuit board are filtered out for noise by capacitors.

[0028] Further, see Figure 2 The external fire protection two-wire bus is connected to the circuit board via terminals. It then passes through a 12R current-limiting resistor connected in series with the circuit and is connected to pins 1 and 2 of the rectifier bridge. Pins 3 and 4 of the rectifier bridge are the positive and negative terminals of the rectified power supply, respectively, and are connected to pins 1 and 3 of the CS2132ALO. This ensures that the two wires of the bus can supply power to the device regardless of whether they are connected in the correct or reverse direction, thus achieving non-polarity power supply to the device.

[0029] The AVDD pin of the CS2132ALO fire detection chip is connected to the first terminal of resistor R4. The second terminal of resistor R4 is connected to the first terminal of NTC thermistor R5 and pin PA4 / AN1 of the CS2132ALO. The second terminal of NTC thermistor R5 is connected to pin PA5 of the CS2132ALO. Pin PA5 of the CS2132ALO controls whether current flows through NTC thermistor R5. Pin PA4 / AN1 of the CS2132ALO is the ADC port, used to acquire the voltage value of the NTC thermistor and convert the voltage value into a digital signal. When the ambient temperature rises, the resistance of the NTC thermistor decreases, and the voltage division value acquired by the ADC also decreases. By comparing this value with the set alarm threshold, the temperature detection result is obtained.

[0030] See Figure 2 The fire detection chip CS2132ALO is connected to an LED and a current-limiting resistor R6 via pin PB3 / AN3 to indicate the device's operating status.

[0031] See Figure 2 , Figure 3 and Figure 4 The fire detection chip CS2132ALO's internal LDO reduces the bus voltage to 5V and outputs it to the power pin AVDD. The power pin AVDD is connected to pins 1 and 3 of the power chip LP5907. Pin 5 of the power chip LP5907 is connected to the two VDD pins of the Bluetooth chip nRF52805, providing it with a 3.3V operating voltage.

[0032] See Figure 4 The Bluetooth chip nRF52805 is connected to a 32.768K crystal via pins P0.00 / XL1 and P0.01 / XL2, and to a 32M crystal via pins XC1 and XC2. Each pin of the two crystals is connected to a matching capacitor to ensure stable operation of the crystals and provide a precise operating frequency for the Bluetooth chip.

[0033] Further, see Figure 4 The Bluetooth chip nRF52805 connects to the first terminal of inductor L1 via pin ANT. The second terminal of inductor L1 is connected to the first terminal of inductor L2 and the first terminal of capacitor C3. The second terminal of inductor L2 is connected to the antenna, and the second terminal of capacitor C3 is grounded. Inductors L1, L2, and capacitor C3 form an impedance matching network, matching the output impedance of the antenna circuit to the standard 50Ω, reducing Bluetooth signal reflection and improving transmission efficiency.

[0034] Further, see Figure 2 , Figure 4 and Figure 5The IO pin level of the fire detection chip CS2132ALO is 5V, and the IO pin level of the Bluetooth chip nRF52805 is 3.3V. Pins 1 and 8 of the voltage converter TXB0102 are connected to pins PA2 and PA3 of the fire detection chip CS2132ALO, and pins 4 and 5 of the voltage converter TXB0102 are connected to pins P0.14 and P0.12 of the Bluetooth chip nRF52805. Through the voltage converter, bidirectional conversion between 5V and 3.3V IO levels and UART communication between the two chips are realized, thereby achieving the purpose of the fire detection chip controlling the Bluetooth chip and receiving data.

[0035] This invention, by incorporating a rectifier bridge, a fire detection chip, an NTC thermistor, a Bluetooth chip, a power chip, a voltage converter, and an LED indicator, can not only detect fires by monitoring ambient temperature, but also locate trapped personnel and firefighters in a fire using Bluetooth with extremely low power consumption. The location accuracy is high, the speed is fast, and the impact on the existing fire protection system is minimal.

[0036] In addition, the device's low power consumption ensures its stability and reliability during long-term operation, thereby further improving the efficiency and response speed of the overall fire safety system.

[0037] The working principle of this invention is as follows: The resistance of the NTC thermistor decreases significantly with increasing temperature. The fire detection chip periodically collects the voltage division value of the thermistor through an ADC to detect the ambient temperature. When the detected value exceeds a preset threshold, the fire detection chip sends a temperature alarm to the controller via a two-wire bus, and the LED indicator stays on. Simultaneously, it sends control commands to the Bluetooth chip via a serial port to increase the Bluetooth broadcast frequency, thereby improving the positioning accuracy and speed of personnel within the area. Mobile devices entering the positioning area receive Bluetooth broadcast information and upload the received data to a cloud server. The server database contains preset maps and Bluetooth module binding information. The collected data is processed by a positioning algorithm to calculate the floor and coordinates of the mobile device, which is then displayed on the server map platform and the mobile device, achieving personnel positioning.

[0038] The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0039] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A heat-sensing fire detector with Bluetooth positioning function, comprising a circuit board disposed inside the fire detector, characterized in that: The circuit board includes a rectifier bridge, a fire detection chip, an NTC thermistor, a Bluetooth chip, a power supply chip, a voltage converter, and LED indicators. The circuit board is connected to the fire alarm bus via terminals. The bus is connected to the CS2132ALO fire detection chip via the rectifier bridge. The CS2132ALO fire detection chip is connected to the NTC thermistor via pins for ambient temperature detection. The CS2132ALO fire detection chip is also connected to the LED indicators via pins to indicate the device's operating status. The CS2132ALO fire detection chip's internal LDO converts 24V... The bus voltage is reduced to 5V and output to the power supply pin. The 5V power supply pin of the fire detection chip CS2132ALO is connected to the input pin of the power supply chip. The 3.3V output pin of the power supply chip is connected to the Bluetooth chip nRF52805 to power the Bluetooth chip. The Bluetooth chip nRF52805 is connected to the crystal and the antenna through its pins. One end of the voltage converter pin is connected to the fire detection chip CS2132ALO, and the other end is connected to the Bluetooth chip nRF52805, thus realizing the connection between the fire detection chip and the Bluetooth chip.

2. A heat-sensing fire detector with Bluetooth positioning function according to claim 1, characterized in that: The fire detection chip CS2132ALO is connected to an NTC thermistor and uses an ADC to periodically collect the thermistor voltage value to complete the ambient temperature detection.

3. A heat-sensing fire detector with Bluetooth positioning function according to claim 1, characterized in that: The Bluetooth circuit of the nRF52805 Bluetooth chip uses 32M and 32.768K crystals, and the pins of the crystals are connected to matching capacitors respectively.

4. A heat-sensing fire detector with Bluetooth positioning function according to claim 1 or 3, characterized in that: The Bluetooth chip nRF52805 pins are connected to the antenna after passing through a filter capacitor and a filter inductor.

5. A heat-sensing fire detector with Bluetooth positioning function according to claim 1, characterized in that: The power supply pins of the circuit board have their input and output terminals filtered out by capacitors.

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