Smoke sensor capable of adjusting smoke sensitivity on site

Abstract

The utility model discloses a smoke sensor capable of adjusting smoke sensitivity on site, which comprises a shell with an opening at one end, a smoke inlet protective cover is covered at the opening of the shell through a sealing ring, a core body used for detecting smoke concentration is arranged in the smoke inlet protective cover, and the core body is connected with a cable. The cable is electrically connected with other adapter equipment through a cable gland mounted on the side wall of the shell; the core body comprises a PIC16F single chip microcomputer, the PIC16F single chip microcomputer is electrically connected with the smoke detection chamber, the smoke detection chamber converts a detected smoke concentration signal into an electric signal and then transmits the electric signal to the PIC16F single chip microcomputer, and the PIC16F single chip microcomputer processes the signal and then outputs the signal; the PIC16F single chip microcomputer is electrically connected with the potentiometer, the potentiometer is provided with a cross-shaped rotating core body for adjusting the sensitivity, the cross-shaped rotating core body of the potentiometer is located in the shell, and the sensitivity of the smoke sensor is adjusted by rotating the cross-shaped rotating core body. According to the utility model, the sensitivity of the smoke sensor can be adjusted, so that the smoke sensor can be suitable for more places.

Description

Technical Field

[0001] The utility model belongs to the technical field of smoke sensors, and relates to a smoke sensor with adjustable smoke sensitivity on site. Background Technique

[0002] With the improvement of people's safety awareness, fire prevention and monitoring have become increasingly important. As an important fire warning device, a smoke sensor (hereinafter referred to as the sensor) can detect the smoke generated by a fire in a timely manner and issue an alarm, helping people take corresponding measures to protect life and property safety.

[0003] In industrial production, fire prevention is particularly important. In order to detect and control the fire early, the sensor is generally connected to the corresponding protection device for real-time online monitoring of smoke. When the smoke concentration detected by the sensor is greater than the threshold value, the sensor emits an alarm signal. After receiving the alarm signal, the protection device issues a corresponding alarm and protects and stops the controlled associated equipment to prevent the further expansion of the fire.

[0004] During the industrial production process, there are often a large amount of production dust. These dusts are not the accompaniments of fires, but the sensor cannot distinguish them. When the dust concentration is greater than the sensor threshold value, the sensor will emit a false alarm signal, which will affect normal production. In such a situation, the ideal solution is to lower the sensor sensitivity so that its threshold value is slightly higher than the dust concentration value during production. During normal production, if a fire occurs, the smoke superimposed on the dust concentration will be higher than the sensor threshold value, causing the sensor to alarm, and the protection device will perform normal protection operations. Since the production sites are different and the production dust concentrations accompanied by their production processes are also different, it is of great significance to design a sensor with adjustable sensitivity on site to improve the sensitivity of the sensor as much as possible. Summary of the Invention

[0005] In view of this, the purpose of the utility model is to provide a smoke sensor with adjustable smoke sensitivity on site that can solve the above problems.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A smoke sensor with adjustable smoke sensitivity on site includes a housing with an open end. The opening of the housing is covered with a smoke inlet protection cover through a sealing ring. The smoke inlet protection cover is provided with a plurality of mesh holes for the passage of smoke. The inside of the smoke inlet protection cover is a core body for detecting the smoke concentration. The core body is connected with a cable, and the cable is electrically connected to other mating devices through a gland installed on the side wall of the housing;

[0008] The core body includes a PIC16F single-chip microcomputer, which is electrically connected to the smoke detection chamber. The smoke detection chamber converts the detected smoke signal into an electrical signal and transmits it to the PIC16F single-chip microcomputer. The PIC16F single-chip microcomputer processes the signal and then outputs it.

[0009] The PIC16F single-chip microcomputer is electrically connected to a potentiometer. The potentiometer has a cross-rotating core for adjusting sensitivity. The cross-rotating core of the potentiometer is located inside the housing, and the sensitivity of the smoke sensor is adjusted by rotating the cross-rotating core.

[0010] Furthermore, the model of the potentiometer is 3362.

[0011] Furthermore, there is an arrow mark on the cross-rotating core, and there are scale marks on the periphery of the cross-rotating core. When the cross-rotating core is rotated clockwise, the sensitivity of the smoke sensor increases; conversely, the sensitivity of the smoke sensor decreases.

[0012] Furthermore, the housing is made of metal material, and the smoke inlet protection cover is made of stainless steel by stamping.

[0013] Furthermore, the output end of the PIC16F single-chip microcomputer is electrically connected to pin 2 of the relay. Pin 1 of the relay is connected to the power supply VCC. Pin 3 of the relay is electrically connected to one end of resistor R1 and resistor R2. The other end of resistor R1 is the signal output end for connecting to the configured protection device. The other end of resistor R2 is electrically connected to pin 4 of the relay and then outputs a signal to the configured protection device.

[0014] The beneficial effects of the present utility model are as follows:

[0015] The present utility model can adjust the sensitivity of the smoke sensor, making it applicable to more places. In the case of large dust, the sensitivity of the smoke sensor is lowered to prevent false alarms. In the case of small dust, the sensitivity is increased to improve the timeliness of fire alarms. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0017] Figure 1 is a schematic structural diagram of an embodiment of the present utility model;

[0018] Figure 2 is a detection principle block diagram of the smoke detection module according to the embodiment of the present utility model.

[0019] Description of the reference numerals:

[0020] 1. Housing; 2. Gasket; 3. Core; 4. Smoke inlet protective cover; 5. Cable gland; 6. Cable. Detailed implementation manner

[0021] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments may be combined with each other.

[0022] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model 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 should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0023] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific situations.

[0024] The present utility model will be described in detail below with reference to the drawings and in combination with embodiments.

[0025] As shown in the figure, a smoke sensor capable of adjusting the smoke sensitivity on-site includes a housing 1 with an opening at one end. The opening of the housing 1 is covered with a smoke inlet protective cover 4 through a sealing ring. The smoke inlet protective cover 4 is provided with a plurality of mesh holes for the passage of smoke. The inside of the smoke inlet protective cover 4 is a core 3 for detecting the smoke concentration. The core 3 is connected with a cable 6, and the cable 6 is electrically connected to other mating devices through a cable gland 5 installed on the side wall of the housing 1.

[0026] The housing 1 is made of metal material, and the smoke inlet protective cover 4 is made by stamping stainless steel. The sensor uses a metal housing 1, which greatly improves the strength compared with the sensor with a plastic housing 1, and is more suitable for the harsh environments in industrial production.

[0027] The core body 3 includes a PIC16F single-chip microcomputer, which is electrically connected to the smoke detection chamber. The smoke detection chamber converts the detected smoke concentration signal into an electrical signal and transmits it to the PIC16F single-chip microcomputer, and the PIC16F single-chip microcomputer processes the signal and then outputs it.

[0028] Smoke sensors on the market are divided into ion type, gas-sensitive type, and optoelectronic type. The ion type has disadvantages such as having a radiation source inside and being greatly affected by air humidity, making its requirements for the application environment relatively harsh; the gas-sensitive smoke sensor is easily interfered by other combustible gases and misoperates, and the internal gas-sensitive material generates high temperature during operation, restricting its application in many industrial and mining sites.

[0029] The optoelectronic smoke sensor has the characteristics of a wide applicable range, fast detection speed, and stable performance. This smoke sensor is an optoelectronic smoke sensor, which is designed by utilizing the reflection and scattering characteristics of smoke to light. A black smoke detection chamber is provided at the lower end of the sensor. There are ventilation holes around the smoke detection chamber, and external light will be absorbed by the black baffle of the smoke detection chamber and cannot reach the inside of the smoke detection chamber, so as to avoid the interference of external light. Inside the smoke detection chamber, there is a pair of infrared opposed phototransistors not on the same optical path. When there is no smoke entering, the infrared receiving transistor cannot receive the infrared rays emitted by the infrared emitting transistor, and it shows a high impedance state; when external smoke enters the inside through the ventilation holes of the smoke detection chamber, the infrared rays are reflected and refracted by the smoke particles and then received by the infrared receiving transistor, making it show a low impedance state. The greater the smoke concentration, the lower its impedance.

[0030] The PIC16F single-chip microcomputer is electrically connected to a potentiometer, and the model of the potentiometer is 3362 type. The potentiometer has a cross-rotating core for adjusting sensitivity. The cross-rotating core of the potentiometer is located on the circuit board inside the housing 1. There is an arrow mark on the cross-rotating core of this type of potentiometer, which can be used to quantitatively adjust the sensitivity in cooperation with the surrounding scale marks. When adjustment is needed, open the smoke inlet protective cover 4 for adjustment, and then cover the smoke inlet protective cover 4 after adjustment. Rotating the cross-rotating core of the potentiometer clockwise increases the sensitivity, and vice versa, the sensitivity decreases.

[0031] The PIC16F single-chip microcomputer emits a 10us-wide pulse every 100ms through its internally integrated output comparison module to turn on the infrared light-emitting diode of the smoke detection module to emit infrared rays. At the same time, the single-chip microcomputer uses the A / D conversion function to detect the state of the infrared receiving transistor. After program filtering, the voltage of the detected infrared receiving transistor is compared with the voltage of the detected potentiometer. If it is lower than the potentiometer voltage, a smoke alarm output is performed.

[0032] The output terminal of the PIC16F single-chip microcomputer is electrically connected to pin 2 of the relay. Pin 1 of the relay is connected to the power supply VCC. Pin 3 of the relay is electrically connected to one end of resistor R1 and resistor R2. The other end of resistor R1 is the signal output terminal for the protection device of the chip. The other end of resistor R2 is electrically connected to pin 4 of the relay and then outputs a signal to the connected protection device.

[0033] The PIC16F single-chip microcomputer adopts a resistance output form. When there is no smoke alarm, the relay is closed, R2 is short-circuited, and the signal outputs the resistance R1. When a smoke alarm occurs, the relay of the sensor is disconnected, and the signal outputs the resistance R1 + R2.

[0034] The connected protection device is electrically connected to the output terminal of the smoke sensor by means of analog quantity detection. By detecting the resistance value, four states can be detected: normal smoke sensor (R1), smoke sensor alarm (R1 + R2), signal transmission line short circuit (0Ω), and signal transmission line open circuit (+∞). When a line fails, it can promptly alarm the staff to facilitate early resolution of potential hazards.

[0035] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A smoke sensor with adjustable smoke sensitivity on-site, characterized in that: It includes a housing (1) with one end open. The opening of the housing (1) is covered with a smoke inlet protection cover (4) through a sealing ring. A number of mesh holes are opened on the smoke inlet protection cover (4) to facilitate the passage of smoke. Inside the smoke inlet protection cover (4) is a core body (3) for detecting the smoke concentration. The core body (3) is connected to a cable (6), and the cable (6) is connected to a gland (5). The gland (5) extends to the outside of the housing (1) at the side wall of the housing (1) for electrically connecting the cable to other mating devices; The core body (3) includes a PIC16F single-chip microcomputer. The PIC16F single-chip microcomputer is electrically connected to a smoke detection chamber. The smoke detection chamber transmits the detected signal to the PIC16F single-chip microcomputer, and the PIC16F single-chip microcomputer processes and outputs the signal; The PIC16F single-chip microcomputer is electrically connected to a potentiometer. The potentiometer has a cross-rotating core for adjusting the sensitivity. The cross-rotating core of the potentiometer is located inside the housing (1). The sensitivity of the smoke sensor can be adjusted by rotating the cross-rotating core.

2. The smoke sensor capable of adjusting the smoke sensitivity on-site according to claim 1, wherein: The model of the potentiometer is type 3362.

3. The smoke sensor with on-site adjustable smoke sensitivity according to claim 2, characterized in that: There is an arrow mark on the cross-rotating core, and there are scale marks on the periphery of the cross-rotating core. Rotating the cross-rotating core clockwise increases the sensitivity of the smoke sensor, and vice versa, rotating the cross-rotating core counterclockwise decreases the sensitivity of the smoke sensor.

4. The smoke sensor capable of on-site adjusting the smoke sensitivity according to claim 1, characterized in that: The housing (1) is made of metal material, and the smoke inlet protection cover (4) is made by stamping stainless steel.

5. The smoke sensor with on-site adjustable smoke sensitivity according to claim 1, characterized in that: The output end of the PIC16F single-chip microcomputer is electrically connected to pin 2 of the relay. Pin 1 of the relay is connected to the power supply VCC. Pin 3 of the relay is electrically connected to one end of resistor R1 and resistor R2. The other end of resistor R1 is the signal output end to the protection device of the chip. The other end of resistor R2 is electrically connected to pin 4 of the relay and then outputs the signal to the mating protection device.

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