Pyrolysis particle detection cloud chamber based on optical fiber optical path

Abstract

The invention relates to a pyrolysis particle detection cloud chamber based on an optical fiber optical path in the field of fire detection, through an incident optical fiber and an emergent optical fiber which extend into a non-transparent shell, detection light does not need to penetrate through the shell wall of the cloud chamber, and the influence on a detection result due to refraction of the detection light in the shell wall of the cloud chamber is reduced; meanwhile, water drops and water films condensed on the inner wall of the cloud chamber shell cannot influence the light path of the detection light, so that the detection accuracy is further improved; besides, the non-transparent shell enables ambient light not to enter the cloud chamber shell, so that interference of external light to detection light is reduced, and the detection accuracy is improved; in addition, through a first water diversion line arranged on the top wall in the cloud chamber, the possibility that condensed water drops drop on a light path is reduced, and the detection accuracy is further improved.

Description

Technical Field

[0001] The present invention relates to a detection cloud chamber, and particularly to a pyrolysis particle detection cloud chamber based on an optical fiber optical path applied to the field of fire detection. Background Art

[0002] In recent years, cloud chamber technology has been used as a means for detecting fire hazards. The basic principle of this technology is to precisely control the gas temperature and humidity conditions in the cloud chamber cavity, enabling tiny pyrolysis smoke particles to act as cloud condensation nuclei, thereby causing the gas molecules around these particles to condense into droplets. Subsequently, advanced optical sensors are used to efficiently detect these droplets to accurately identify early signs of fire.

[0003] Please refer to the attached Figure 2 . The existing detection cloud chamber includes a transparent outer shell, a light source emitter and a photoelectric sensor oppositely arranged on both sides of the transparent outer shell. During detection, the detection light generated by the light source emitter first passes through the wall on the left side of the transparent outer shell, then irradiates the sampled gas, and then the detection light passing through the sampled gas penetrates the wall of the transparent outer shell again and is received by the photoelectric sensor.

[0004] In the existing detection cloud chamber, since the droplets formed with pyrolysis particles as condensation nuclei will continue to condense on the inner wall of the transparent outer shell, forming condensed water droplets and water films on the inner wall of the transparent outer shell, which block the detection light and thus affect the detection accuracy of the detection light. Summary of the Invention

[0005] Aiming at the above-mentioned prior art, the technical problem to be solved by the present invention is that the water droplets and water films formed by the condensation of droplets on the inner wall of the detection cloud chamber affect the detection accuracy.

[0006] To solve the above problems, the present invention provides a pyrolysis particle detection cloud chamber based on an optical fiber optical path, including a non-transparent housing, an inlet pipe and an outlet pipe which are fixedly communicated on both sides of the non-transparent housing and communicated with its inner cavity, a light source emitter fixedly connected to the outer wall of one side of the non-transparent housing, an incident optical fiber fixedly connected to the light source emitter and extending into the non-transparent housing, a photoelectric sensor fixedly connected to the outer wall of the non-transparent housing on the side opposite to the light source emitter, and an exit optical fiber fixedly connected to the photoelectric sensor and extending into the non-transparent housing and oppositely arranged with the incident optical fiber.

[0007] In the above-mentioned pyrolysis particle detection cloud chamber based on an optical fiber optical path, the influence of droplet condensation on the inner wall of the cloud chamber on the detection result is reduced by the incident optical fiber and the exit optical fiber extending into the non-transparent housing.

[0008] As a further improvement of the present application, a plurality of first water diversion lines are fixedly connected to the inner top wall of the non-transparent housing, and the first water diversion lines are used to guide the condensed water droplets located directly above the detection optical path to the outside of the detection optical path.

[0009] As a further improvement of the present application, both the light source emitter and the photoelectric sensor are connected to the same controller, and the controller is equipped with a calculation module.

[0010] As a further improvement of the present application, the inner wall of the non-transparent housing is sprayed with light-absorbing paint, and the light-absorbing paint is carbon black light-absorbing paint and titanium oxide light-absorbing paint.

[0011] As a further improvement of the present application, the non-transparent housing is a horizontal cylindrical structure, the upper end of the first water diversion line is fixedly connected to the central position of the top wall of the non-transparent housing, and the plurality of first water diversion lines are evenly and staggeredly distributed on the inner top wall of the non-transparent housing.

[0012] As a further improvement of the present application, a pair of oppositely arranged guiding cylinders are fixedly connected to the inner wall of the non-transparent housing, the pair of guiding cylinders are respectively sleeved outside the incident optical fiber and the outgoing optical fiber, and a plurality of second water diversion lines are fixedly connected to the lower end of the guiding cylinder, and the lower end of the second water diversion line is fixedly connected to the inner wall of the non-transparent housing.

[0013] As a further improvement of the present application, the guiding cylinder is a horizontally arranged conical cylinder structure, and the ends with larger diameters of the pair of guiding cylinders are arranged oppositely.

[0014] As a further improvement of the present application, when performing pyrolysis particle detection, the following steps are included:

[0015] Step 1, injecting the sampled gas into the non-transparent housing;

[0016] Step 2, starting the light source emitter and the photoelectric sensor, and measuring the light intensity at this time as L0;

[0017] Step 3, cooling the non-transparent housing so that the sampled gas in the non-transparent housing reaches a supersaturated state and forms droplets with pyrolysis particles as condensation nuclei;

[0018] Step 4, starting the light source emitter and the photoelectric sensor again, and measuring the light intensity at this time as L1;

[0019] Step 5, according to the Beer-Lambert law: c = log(L0 / L1) / (e*L), the relationship between the pyrolysis particle concentration c and L0, L1 can be known, where e is a constant, and L is the gas path length between the two opposed optical fibers. Substituting the above values, the concentration of pyrolysis particles can be calculated.

[0020] In summary, through the incident optical fiber and the outgoing optical fiber extending into the non-transparent housing, the present invention enables the detection light to not need to pass through the cloud chamber housing wall, reducing the influence on the detection result caused by the refraction of the detection light in the cloud chamber housing wall. At the same time, the water droplets and water films condensed on the inner wall of the cloud chamber housing cannot affect the optical path of the detection light, further improving the accuracy of detection. In addition, the non-transparent housing prevents environmental light from entering the cloud chamber housing, reducing the interference of external light on the detection light and improving the accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the present application;

[0022] Figure 2 is a schematic structural diagram of an existing detection cloud chamber;

[0023] Figure 3 is a three-dimensional structural diagram of the present application;

[0024] Figure 4 is a schematic cross-sectional structural diagram of the present application in the horizontal direction;

[0025] Figure 5 is a schematic cross-sectional structural diagram of the present application in the longitudinal direction;

[0026] Figure 6 is a schematic diagram of the state where condensed water droplets fall on the detection optical path in the present application;

[0027] Figure 7 is a schematic diagram of the first water diversion line guiding the condensed water droplets in the present application;

[0028] Figure 8 is an enlarged schematic diagram of part A in TU 4;

[0029] Figure 9 is an assembly schematic diagram of the guiding cylinder and the second water diversion rope in the present application.

[0030] Explanation of the reference numerals in the drawings:

[0031] 1. Non-transparent housing; 2. Inlet pipe; 3. Outlet pipe; 4. Light source emitter; 5. Incident optical fiber; 6. Photoelectric sensor; 7. Outgoing optical fiber; 8. First water diversion line; 9. Guiding cylinder; 10. Second water diversion line. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following provides a detailed description of two embodiments of the present application with reference to the drawings.

[0033] The first embodiment:

[0034] Figures 1-3Disclosed is a pyrolysis particle detection cloud chamber based on an optical fiber light path, which includes an opaque housing 1. The opaque housing 1 is fixedly connected to an intake pipe 2 and an outlet pipe 3 distributed on both sides thereof and communicating with its inner cavity. On one outer wall of the opaque housing 1, a light source emitter 4 is fixedly connected. The light source emitter 4 is fixedly connected to an incident optical fiber 5 extending into the opaque housing 1. On the outer wall of the opaque housing 1 opposite to the light source emitter 4, a photoelectric sensor 6 is fixedly connected. The photoelectric sensor 6 is fixedly connected to an outgoing optical fiber 7 extending into the opaque housing 1 and arranged opposite to the incident optical fiber 5.

[0035] During use, it includes the following steps:

[0036] Step 1, inject the sampling gas into the opaque housing 1;

[0037] Specifically, the intake pipe 2 and the outlet pipe 3 are connected to an external air pump, and the external gas is sampled by the air pump.

[0038] Step 2, start the light source emitter 4 and the photoelectric sensor 6, and measure the light intensity at this time as L0;

[0039] Specifically, the light source emitted by the light source emitter 4 enters the opaque housing 1 through the incident optical fiber 5, then enters the outgoing optical fiber 7 through the inner cavity of the opaque housing 1, and the outgoing optical fiber 7 transmits the received light to the photoelectric sensor 6, and the photoelectric sensor 6 detects the intensity of the received light.

[0040] Step 3, cool the opaque housing 1 so that the sampling gas in the opaque housing 1 reaches a supersaturated state and forms droplets with pyrolysis particles as condensation nuclei;

[0041] Specifically, the opaque housing 1 is cooled by a semiconductor refrigeration sheet or a refrigeration jacket arranged on the outside of the opaque housing 1. Among them, the refrigeration jacket is connected to an external heat-conducting oil refrigeration machine. The cooling of the opaque housing 1 is a prior art and will not be elaborated in this application.

[0042] Step 4, start the light source emitter 4 and the photoelectric sensor 6 again, and measure the light intensity at this time as L1;

[0043] Specifically, the emitted detection light will be blocked by the droplets and refracted, resulting in a change in the intensity of the outgoing light.

[0044] Step 5, according to the Beer-Lambert law: c = log(L0 / L1) / (e*L), the relationship between the pyrolysis particle concentration c and L0, L1 can be known, where e is a constant and L is the gas path length between the two opposing optical fibers. Substitute the above values to calculate the concentration of pyrolysis particles.

[0045] Compared with the traditional detection cloud chamber, in the present invention, through the incident optical fiber 5 and the outgoing optical fiber 7 extending into the non-transparent housing 1, the detection light does not need to pass through the cloud chamber wall, reducing the influence on the detection result caused by the refraction of the detection light in the cloud chamber wall. At the same time, the water droplets and water films condensed on the inner wall of the cloud chamber housing cannot affect the optical path of the detection light, further improving the detection accuracy; in addition, the non-transparent housing 1 prevents ambient light from entering the cloud chamber housing, reducing the interference of external light on the detection light and improving the detection accuracy.

[0046] In this embodiment, both the light source emitter 4 and the photoelectric sensor 6 are connected to the same controller, and the controller is equipped with a calculation module.

[0047] Specifically, the calculation module calculates the concentration of pyrolysis particles.

[0048] In this embodiment, the inner wall of the non-transparent housing 1 is sprayed with light-absorbing paint, and the light-absorbing paint is carbon black light-absorbing paint and titanium oxide light-absorbing paint.

[0049] Specifically, the light-absorbing paint reduces the reflection and refraction of the refracted light in the non-transparent housing 1, further reducing the interference with the detection light.

[0050] The second implementation mode:

[0051] Figures 4-9 A pyrolysis particle detection cloud chamber based on an optical fiber optical path is shown. On the basis of the first implementation mode, a plurality of first water diversion lines 8 are fixedly connected to the inner top wall of the non-transparent housing 1, and the first water diversion lines 8 are used to guide the condensed water droplets located directly above the detection optical path to the outside of the detection optical path.

[0052] Specifically, please refer to Figure 6 and Figure 7 , when the fog droplets and water vapor in the non-transparent housing 1 condense into water droplets on its inner wall, the condensed water droplets are guided to the outside of the detection optical path through the first water diversion lines 8, so that the condensed water droplets will not gather and drip directly above the detection optical path, overcoming the influence of the dripping water droplets on the detection light; it should be noted that the detection optical path is the optical path of the detection light between the incident optical fiber 5 and the outgoing optical fiber 7. When the condensed water droplets pass through the optical path, they will not only cause refraction of the detection light, but also cause adsorption of the fog droplets, thereby affecting the detection accuracy.

[0053] Please refer to Figure 5 , the non-transparent housing 1 is a horizontal cylindrical structure, the upper ends of the first water diversion lines 8 are fixedly connected to the central position of the top wall of the non-transparent housing 1, and the plurality of first water diversion lines 8 are evenly and staggeredly distributed on the inner top wall of the non-transparent housing 1.

[0054] Specifically, the cylindrical opaque housing 1 reduces the condensation of droplets on the top of the opaque housing 1, and the first water diversion lines 8 distributed at equal intervals and staggered improve the guiding effect on the condensed water droplets.

[0055] Please refer to Figure 4 and Figure 8 , a pair of oppositely arranged guiding cylinders 9 are fixedly connected to the inner wall of the opaque housing 1, and the pair of guiding cylinders 9 are respectively sleeved outside the incident optical fiber 5 and the outgoing optical fiber 7.

[0056] Specifically, the incident optical fiber 5 and the outgoing optical fiber 7 are fixedly limited by a pair of guiding cylinders 9 to ensure the linearity of the detection light and improve the detection effect.

[0057] Please refer to Figure 7 and Figure 8 , a plurality of second water diversion lines 10 are fixedly connected to the lower end of the guiding cylinder 9, and the lower ends of the second water diversion lines 10 are fixedly connected to the inner wall of the opaque housing 1.

[0058] Specifically, through the guiding cylinder 9 and the second water diversion lines 10, the condensation of droplets on the incident optical fiber 5 and the outgoing optical fiber 7 is reduced, and the water droplets condensed on the guiding cylinder 9 are guided to the inner wall of the opaque housing 1, reducing the accumulation of water droplets on the guiding cylinder 9.

[0059] Please refer to Figure 9 , the guiding cylinder 9 is a horizontally arranged conical cylinder structure, and the relatively larger diameter ends of the pair of guiding cylinders 9 are arranged oppositely.

[0060] Specifically, the condensed water droplets flow on the outer wall of the guiding cylinder 9 in a direction away from the end faces of the incident optical fiber 5 and the outgoing optical fiber 7, reducing the wetting probability of the condensed water droplets on the end faces of the incident optical fiber 5 and the outgoing optical fiber 7 and improving the detection accuracy.

[0061] Please refer to Figure 3 , both the air inlet pipe 2 and the air outlet pipe 3 are tangentially communicated with the inner cavity of the opaque housing 1.

[0062] Specifically, when it is necessary to clean the inside of the opaque housing 1, the cleaning gas tangentially blows the inner wall of the opaque housing 1 through the tangentially communicated air inlet pipe 2 and air outlet pipe 3, improving the cleaning effect and thus improving the accuracy of continuous detection.

[0063] Combined with the current actual requirements, the above-mentioned implementation manners adopted in this application, the protection scope is not limited thereto. Within the scope of knowledge possessed by those skilled in the art, various changes made without departing from the concept of this application still fall within the protection scope of the present invention.

Claims

1. A pyrolysis particle detection cloud chamber based on optical fiber light path, characterized in that: The invention comprises a non-transparent shell (1), wherein the non-transparent shell (1) is fixedly connected to an air inlet pipe (2) and an air outlet pipe (3) which are distributed on both sides and are connected to an inner cavity of the non-transparent shell (1), a light source emitter (4) is fixedly connected to an outer wall of one side of the non-transparent shell (1), the light source emitter (4) is fixedly connected to an incident optical fiber (5) extending into the non-transparent shell (1), and a photoelectric sensor (6) is fixedly connected to an outer wall of a side of the non-transparent shell (1) opposite to the light source emitter (4), and the photoelectric sensor (6) is fixedly connected to an output optical fiber (7) which extends into the non-transparent shell (1) and is arranged opposite to the incident optical fiber (5).

2. A pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 1, characterized in that: A plurality of first water guide lines (8) are fixedly connected to the inner top wall of the non-transparent shell (1), and the first water guide lines (8) are used to guide condensed water droplets condensed just above the detection light path to the outside of the detection light path.

3. The pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 1, characterized in that: The light source emitter (4) and the photoelectric sensor (6) are both connected to the same controller, and the controller is equipped with a computing module.

4. The pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 1, characterized in that: The inner wall of the non-transparent shell (1) is sprayed with light-absorbing paint, and the light-absorbing paint is carbon black light-absorbing paint and titanium oxide light-absorbing paint.

5. The pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 2, characterized in that: The non-transparent shell (1) is a horizontal cylindrical structure, the upper end of the first water guide line (8) is fixedly connected to the center position of the top wall of the non-transparent shell (1), and a plurality of first water guide lines (8) are distributed on the inner top wall of the non-transparent shell (1) at equal intervals and in an interlaced manner.

6. The pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 2, characterized in that: A pair of guide cylinders (9) arranged opposite to each other are fixedly connected to the inner wall of the non-transparent shell (1), and the pair of guide cylinders (9) are respectively sleeved on the outside of the incident optical fiber (5) and the output optical fiber (7), and a plurality of second water guide lines (10) are fixedly connected to the lower ends of the guide cylinders (9), and the lower ends of the second water guide lines (10) are fixedly connected to the inner wall of the non-transparent shell (1).

7. A pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 6, characterized in that: The guide cylinder (9) is a horizontally arranged conical cylinder structure, and the ends of a pair of guide cylinders (9) with larger diameters are arranged opposite to each other.

8. The pyrolysis particle detection cloud chamber based on optical fiber optical path according to claim 1, characterized in that: When performing pyrolysis particle detection, the following steps are included: Step 1, injecting the sampled gas into the non-transparent shell (1); Step 2, start the light source emitter (4) and the photoelectric sensor (6), and measure the light intensity at this time as L0; Step three, cooling the non-transparent shell (1) so that the sampled gas in the non-transparent shell (1) reaches a supersaturated state and forms droplets with the pyrolysis particles as condensation nuclei; Step 4, start the light source emitter (4) and the photoelectric sensor (6) again, and measure the light intensity at this time as L1; Step 5. According to Beer-Lambert's law: c=log(L0 / L1) / (e*L), the relationship between the pyrolytic particle concentration c and L0 and L1 can be known, where e is a constant and L is the length of the gas path between the two opposing optical fibers. Substituting the above values, the concentration of the pyrolytic particles can be calculated.

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