Summary of the invention
Based on the technical matters that background technology exists, the present invention proposes a kind of scatter-type fire smog detector and condenser thereof, improve the capacity gauge to scattered beam.
A kind of scatter-type fire smog detector condenser that the present invention proposes, comprise concentrator shell, the internal reflection surface of concentrator shell is compound parabolic reflecting surface, light entrance and light outlet is respectively equipped with in the rear and front end of concentrator shell, light entrance comprises end face light entrance and side light entrance, and side light entrance is opened in the side of concentrator shell and crossing with end face light entrance.
In a further embodiment, between side light entrance place plane and the central axis of concentrator shell, there is predetermined angle; Preferably, described predetermined angle is less than or equal to the maximum condensing angle of condenser.
In a further embodiment, the intersection point that side light entrance place plane is crossing with the central axis of concentrator shell is between the rear and front end of concentrator shell.
In a further embodiment, light entrance distance light in side exports between nearest light entrance position and light outlet and has preset distance.
In a further embodiment, end face light entrance is circular arc entrance, and light outlet is round exit, and end face light entrance place circle and the circle of light outlet are the concentric circles of the central axis perpendicular to concentrator shell.
In a further embodiment, the internal reflection surface of concentrator shell is the compound parabolic reflecting surface adopting the two sections of para-curves be arranged symmetrically with to rotate around its axis of symmetry according to compound parabolic concentrator CPC principle and formed;
Preferably, two sections of parabolical focuses drop on the light outlet of concentrator shell.
In a further embodiment, reflectance coating is coated with at the internal reflection surface of concentrator shell;
Preferably, the reflectivity of reflectance coating is improved according to the reflection characteristic design of wavelength to reflectance coating of scattered light.
The present invention proposes a kind of scatter-type fire smog detector, comprising: detector housing, light source, condenser, optical receiver component, wherein, condenser adopts above-mentioned scatter-type fire smog detector condenser;
Detector housing inside has optical detection chamber, light source, condenser, optical receiver component are arranged in the optical detection chamber of detector housing, light source is used for sending illumination beam in optical detection chamber, condenser is for collecting the scattered beam of smoke particle in optical detection chamber, and optical receiver component is located at the optical outlet position of condenser.
In a further embodiment, condenser comprises the first condenser for collecting the forward scattering light of smoke particle, first condenser is positioned at the first side of illumination beam, the central axis of the first condenser and the first angle theta front of illumination beam≤θ 1max, wherein θ 1max is the maximum condensing angle of the first condenser;
Preferably, the side light entrance place plane of the first condenser and illumination beam are arranged in parallel, and have the first predeterminable range between the side light entrance place plane of the first condenser and illumination beam edge;
Preferably, the first condenser central axis side light entrance the central axis of projection straight line in the plane, the normal of projection straight line and illumination beam in the same plane.
In a further embodiment, condenser comprises the second condenser for collecting the back scattering light of smoke particle, second condenser is positioned at the second side of illumination beam, the central axis of the second condenser and the second angle theta back≤90 of illumination beam °+θ 2max, wherein θ 2max is the maximum condensing angle of the second condenser;
Preferably, the side light entrance place plane of the second condenser and illumination beam are arranged vertically, and have the second predeterminable range between the end face light entrance of the second condenser and illumination beam edge;
Preferably, the side light entrance of the second condenser is arranged in the exit direction of illumination beam;
Preferably, the second condenser central axis side light entrance the central axis of projection straight line in the plane, the normal of projection straight line and illumination beam in the same plane.
In scatter-type fire smog detector condenser disclosed by the invention, the internal reflection surface of concentrator shell is compound parabolic reflecting surface, light entrance and light outlet is respectively equipped with in the rear and front end of concentrator shell, light entrance comprises end face light entrance and side light entrance, and side light entrance is opened in the side of concentrator shell and crossing with end face light entrance.By offering ambient light line entrance in the side of concentrator shell, increase the area of light entrance, add the range of receiving to scattered beam, improve the capacity gauge of condenser to scattered beam, thus improve the detection sensitivity of fire smog detector and detect degree of accuracy.
Embodiment
As shown in Figure 1, Fig. 1 is the structural representation of a kind of scatter-type fire smog detector condenser in the embodiment of the present invention.
With reference to Fig. 1, a kind of scatter-type fire smog detector condenser that the embodiment of the present invention proposes, comprise concentrator shell, the internal reflection surface of concentrator shell is compound parabolic reflecting surface, concentrator shell is provided with light entrance 1 and light outlet 2, wherein, light entrance 1 comprises end face light entrance 1A and side light entrance 1B, end face light entrance 1A is located at the first end of concentrator shell, side light entrance 1B is opened in the side of concentrator shell, and side light entrance 1B is crossing with end face light entrance 1A, light outlet 2 is located at the second end of concentrator shell.
In the present embodiment, the internal reflection surface of concentrator shell carries out designing the compound parabolic reflecting surface obtained according to the principle of compound parabolic concentrator CPC (CompoundParabolicConcentrator).
With reference to Fig. 2, in the design process of compound parabolic concentrator CPC, para-curve A is around its focal point F 1 anglec of rotation θ max in the counterclockwise direction, para-curve B is rotated in a clockwise direction angle θ max around its focal point F 2, thus making the focal point F 1 of para-curve A drop on the lower extreme point of para-curve B, the focal point F 2 of para-curve B drops on the lower extreme point of para-curve A.Axle 1 ' and axle 1 are the axis of symmetry before and after para-curve A rotates respectively, axle 2 ' and 2 is the axis of symmetry before and after para-curve B rotates respectively, parabolic segment F1C and F2D rotates a circle about Y-axis symmetry and around Y-axis and forms three-dimensional compound parabolic concentrator CPC, the structure of compound parabolic concentrator CPC as shown in Figure 3, is respectively equipped with light entrance 1' and light outlet 2' at the two ends of CPC.
In the compound parabolic concentrator CPC that above-mentioned rotation obtains, CD is the diameter of CPC light entrance, and F1F2 is the diameter of CPC light outlet, and the disk at F1F2 place is the focal plane of CPC, and θ max is the maximum condensing angle of CPC.The angle theta i of incident ray and Y-axis is defined as angle of incidence of light, as θ i > θ max, incident ray penetrates from light entrance after CPC reflection, and as θ i < θ max, incident ray all converges on light outlet F1F2 through primary event, thus is all collected on light outlet by the luminous energy of θ i < θ max.
According to the ultimate principle of scatter-type fire hazard aerosol fog detection, if there is smoke particle on the travel path of illumination beam, illumination beam impinges upon on smoke particle and carries out scattering product scattered beam, and scattered beam all can exist scattering phenomenon on illumination beam direct of travel.In order to improve the capacity gauge of condenser to scattered beam, light entrance can be increased at condenser along on illumination beam direct of travel, and then improve the ability that scattered beam collected by condenser.Based on compound parabolic concentrator CPC, consider the collecting effect of scattered beam and the difficulty of processing of condenser, in collector designs process, select a plane crossing with the side of compound parabolic concentrator CPC, with a part of side of this plane for benchmark excision condenser, thus the intake section formed in the side of condenser for scattered light incidence, namely for collecting the side light entrance of scattered beam.
Conveniently express and carried out simplified illustration at this paragraph, in fig. 2, in condenser F1CDF2, former light entrance is CD, selects plane EF crossing with condenser F1CDF2, and EDF part is the part of excision, and the new light entrance after excision is CEF; Compared with former light entrance CD, new light entrance CEF can collect more scattered beam on irradiation light direct of travel.In fig. 2 through forward scattering light L1, L2 and L3 of smoke particle scattering, wherein light L1 can be directed on light outlet F1F2 after compound parabolic reflecting surface reflects once, light L2 and L3 then can shine directly on light outlet F1F2, the optical receiver component being arranged on light outlet F1F2 so just can collect more scattered beam, thus enhances the scattered beam capacity gauge of condenser.
According to above-mentioned analysis, in the scatter-type fire smog detector condenser of the present embodiment, the internal reflection surface of concentrator shell is compound parabolic reflecting surface, light entrance comprises end face light entrance and side light entrance, side light entrance is opened in the side of concentrator shell and crossing with end face light entrance, like this, in the collection process of scattered beam, more scattered beam can be collected by offering ambient light line entrance in the side of concentrator shell, thus improve the capacity gauge of condenser to scattered beam.
In FIG, for the ease of expressing and illustrating, in concentrator shell with compound parabolic reflecting surface for reference, by being defined as the rear end of condenser near one end of its focal point, the one end away from its focal point is defined as the front end of condenser; According to above-mentioned setting, light entrance is located at the front end of concentrator shell, and light outlet is located at the rear end of concentrator shell, and side light entrance is opened in the side of concentrator shell and crossing with end face light entrance; The internal reflection surface of concentrator shell and outside wall surface are at the binding site of side light entrance, and by outside wall surface, internally reflecting surface is close, to form light entrance leading edge thinning gradually from outside to inside at light entrance.
In specific design process, the internal reflection surface of concentrator shell is compound parabolic reflecting surface, in order to collect more scattered beam to improve the capacity gauge of condenser to scattered beam, by maximum condensing angle, the light entrance radius of appropriate design condenser, the parameters such as light outlet radius, the particular location of side light entrance in concentrator shell, can significantly improve the capacity gauge of condenser to scattered beam.
In a further embodiment, with reference to Fig. 1, end face light entrance 1A is circular arc entrance, and light outlet is round exit 2, and end face light entrance 1A place circle is concentric circles with the circle of light outlet 2, and this concentric circles is perpendicular to the central axis Y of concentrator shell.
In a particular embodiment, the parabolical focal point F 1 in two ends can be set, F2 drops on the light outlet of concentrator shell, namely light outlet is on the focal plane of composite parabolic reflecting surface, the diameter of light outlet is F1F2, certainly, in actual application, light outlet can be located at front end or the rear end of focal plane, and its needs design according to the technological parameter of practical application and optical parametric.
In a further embodiment, with reference to Fig. 1, the light porch, side in concentrator shell in same plane, and, have predetermined angle theta between side light entrance place plane and the central axis of concentrator shell, this angle theta is less than or equal to the maximum condensing angle theta max of condenser; Such as, maximum condensing angle theta max=35 ° of design condenser, above-mentioned angle theta can be arranged between 30 ° to 35 ° and be advisable.
In a further embodiment, based between side light entrance place plane and the central axis of concentrator shell, there is predetermined angle theta, that is side light entrance place plane is crossing with the central axis of concentrator shell, when particular location designs, as shown in Figure 1, can both intersection points be located between the rear and front end of concentrator shell, namely both intersection points drop on the inside of concentrator shell, or the outside that the intersection point that can also arrange both is in concentrator shell is in the front of end face light outlet.
In a further embodiment, crossing with end face light entrance at concentrator shell upper side light entrance, when the intersection point of the central axis of side light entrance place plane and concentrator shell is between the rear and front end of concentrator shell, the central angle of end face light entrance place circular arc is greater than 0 ° and is less than 180 °.
In a further embodiment, with reference to Fig. 1, side light entrance distance light exports between nearest light entrance position and light outlet has preset distance, side light entrance place plane and light outlet non-intersect.
In the above-described embodiments, concentrator shell can adopt reflecting metal to make, or, concentrator shell can adopt the plastics of coating reflectance coating to make, in the design process of reflectance coating, the reflection characteristic of design reflectivity coating can be carried out, to improve the reflectivity of reflectance coating for this wavelength dispersion light beam according to the wavelength of scattered light.
In a particular embodiment, in the compound parabolic reflecting surface of concentrator shell, maximum condensing angle is 35 °, and focal length is 4.72mm, and focus lateral shift is 3mm, and front end length is 27mm.In the present embodiment, the light entrance of condenser comprises end face light entrance and side light entrance, the angle of the central axis Y of side light entrance place plane and concentrator shell is 32 °, and the intersecting point coordinate of the central axis Y of side light entrance place plane and concentrator shell is 21.5mm.By arranging side light entrance, increasing the area of light entrance, adding the range of receiving to scattered beam, improve the capacity gauge of condenser to scattered beam.
Below by optical simulation software TracePro, optical analogy comparative analysis is carried out to the scattered beam capacity gauge of scatter-type fire smog detector condenser in the present embodiment.
As shown in Figure 4, by TracePro software, to scattered beam collecting effect, optical analogy is carried out to scatter-type fire smog detector condenser (Fig. 4 A) in the embodiment of the present invention and compound parabolic concentrator CPC (Fig. 4 B) in prior art.In optical analogy process, one group of parallel rays is adopted to carry out the light of simulation smoke particle scattering, the ray density of light outlet as can be seen from Fig. 4, compared with prior art CPC (Fig. 4 B), the condenser (Fig. 4 A) of the present embodiment can receive the scattered beam of more smoke particle.
As shown in Figure 5, by TracePro software, to scattered beam collecting effect, optical analogy is carried out to scatter-type fire smog detector condenser (Fig. 5 A) in the embodiment of the present invention and radiation-energy collector (Fig. 5 B) in the photodetector of coating reverberator disclosed in Chinese patent application CN1191361A, because its manufacture difficulty and volume are all comparatively similar, what two models compared has practical significance.
Suppose that the internal surface reflection rate of condenser and radiation-energy collector is all 100% i.e. mirror-reflection, condenser is identical with the light outlet area of radiation-energy collector, the optical receiver component being located at light outlet place has light receiving surface of the same area, and the Surface absorption rate of light receiving surface is all 100%, namely absorbs completely incident ray.In optical analogy process, 10000 light are launched by surface source of light, light is perpendicular to light-emitting area outgoing, and a part of light can be irradiated on light receiving surface through the reflex of condenser, and a part of light can be shone directly on light receiving surface by condenser.By the amount of light that receives on the light receiving surface that contrasts optical receiver component, condenser and radiation-energy collector namely can be compared to the collecting effect of scattered beam.
As shown in Figure 6, according to the relation between the incident ray quantity on the light receiving surface of condenser under different scattering angle and scattering angle, can find out, in the present embodiment, the collecting effect of condenser to scattered beam is better than radiation-energy collector disclosed in application for a patent for invention CN1191361A to the collecting effect of scattered beam.
In scatter-type fire smog detector condenser disclosed in the present embodiment, the light entrance of condenser comprises end face light entrance and side light entrance, side light entrance is opened in the side of concentrator shell and crossing with end face light entrance, by offering ambient light line entrance in the side of concentrator shell, increase the area of light entrance, add the range of receiving to scattered beam, thus improve the ability that scattered beam collected by condenser.
Based on the scatter-type fire smog detector condenser that the present embodiment proposes, apply the above-mentioned condenser embodiment of the present invention and also proposed a kind of scatter-type fire smog detector condenser.
As shown in Figure 7, Fig. 7 is the structural representation of a kind of scatter-type fire smog detector in the embodiment of the present invention.
With reference to Fig. 7, a kind of scatter-type fire smog detector that the embodiment of the present invention proposes, comprising: detector housing 10, light source 11, condenser and optical receiver component, wherein, condenser adopts above-mentioned scatter-type fire smog detector condenser; Accommodating cavity body in detector housing 10 inside forms optical detection chamber, light source 11, condenser, optical receiver component are arranged in the optical detection chamber of detector housing 10, light source 11 for sending illumination beam K in optical detection chamber, condenser is for collecting the scattered beam of smoke particle in optical detection chamber, and the optical outlet position that optical receiver component is located at condenser is for receiving scattered light line and output signal.
In detection process, air enters in the optical detection chamber of detector, illumination beam runs into the smoke particle generation scattering in air in traveling process, such as produce forward scattering light and back scattering light, scattered beam enters condenser from the end face light entrance of condenser and side light entrance, reflect through the inner compound parabolic reflecting surface of condenser, then penetrate from the light outlet of condenser, reboot on optical receiver component and scattered beam is absorbed.
With reference to Fig. 7, in a further embodiment, condenser comprises the first condenser 12, first condenser 12 for collecting the forward scattering light of smoke particle, first condenser 12 can be called forward scattering condenser, and the first condenser 12 is positioned at first side of illumination beam K.
The central axis of the first condenser and the first angle theta front of illumination beam≤θ 1max, wherein θ 1max is the maximum condensing angle of the first condenser and arranges θ 1max=35 °, in figure, the central axis AA ' of the first condenser and the angle ∠ AOC of illumination beam CC ' are θ front, ∠ AOC=32 °.
The side light entrance place plane of the first condenser and illumination beam are arranged in parallel, namely the angle of side light entrance place plane and the first condenser central axis is θ front, and in figure, the angle of side light entrance place plane and the first condenser central axis AA ' is 32 °.
Between the side light entrance place plane of the first condenser and illumination beam edge, there is the first predeterminable range; When ensureing that illumination beam can not inject the first condenser inside, side direction light entrance ad infinitum can press close to illumination beam, and particularly, above-mentioned first predeterminable range is 4mm.
The central axis of the first condenser side light entrance the central axis of projection straight line in the plane, the normal of projection straight line and illumination beam in the same plane.
According to the above-mentioned design of the first condenser, be conducive to the capacity gauge of enhancing first condenser to low-angle forward scattering light, the receiving angle of the first condenser to forward scattering light can be determined quantitatively, and then avoid the first condenser to receive back scattering light.
With reference to Fig. 7, in a further embodiment, condenser comprises the second condenser 13, second condenser 13 is for collecting the back scattering light of smoke particle, second condenser 13 can be called back scattering condenser, second condenser 13 is positioned at second side of illumination beam K, and the side light entrance of the second condenser 13 is arranged towards the exit direction (with the second condenser for reference) of illumination beam K.
The central axis of the second condenser and the second angle theta back≤90 of illumination beam °+θ 2max, wherein θ 2max is the maximum condensing angle of the second condenser and arranges θ 1max=35 °, in figure, the central axis BB ' of the second condenser and the angle ∠ BOC of illumination beam CC ' are θ back, ∠ BOC=90 °+32 °=122 °.
The side light entrance place plane of the second condenser and illumination beam are arranged vertically, namely the angle of side light entrance place plane and the second condenser central axis is θ back-90 °, and in figure, the angle of side light entrance place plane and the second condenser central axis BB ' is 122 °-90 °=32 °
Between the end face light entrance of the second condenser and illumination beam edge, there is the second predeterminable range; When ensureing that condenser front end can not stop illumination beam, the end face light entrance of the second condenser ad infinitum can press close to illumination beam, and particularly, above-mentioned second predeterminable range is 1.6mm.
The central axis of the second condenser side light entrance the central axis of projection straight line in the plane, the normal of projection straight line and illumination beam in the same plane.
According to the above-mentioned design of the second condenser, be conducive to enhancing second condenser to the capacity gauge of back scattering light, the receiving angle scope of the second condenser to back scattering light can be determined quantitatively, the second condenser can also be avoided to receive forward scattering light.
Below by optical simulation software TracePro, optical analogy comparative analysis is carried out to the scattered beam capacity gauge of scatter-type fire smog detector in scatter-type fire smog detector in the present embodiment and prior art.
With reference to Fig. 8, Fig. 8 A is the analog result that in the present embodiment detector, forward scattering condenser receives light data, Fig. 8 B is the analog result that in the present embodiment, back scattering condenser receives light data, Fig. 8 C is the analog result that in prior art detector, forward scattering condenser receives light data, Fig. 8 D is the analog result that in prior art detector, back scattering condenser receives light data, wherein, the numeral in figure is the amount of light that the light outlet of condenser receives.
The scatter-type fire smog detector of the present embodiment have employed the condenser shown in Fig. 1, and the scatter-type fire smog detector of prior art have employed the condenser shown in Fig. 3, and in two detectors, condenser has identical installation site.In the detector of the present embodiment, forward scattering condenser has side light entrance and side light entrance place plane and illumination beam are arranged in parallel, and therefore, forward scattering condenser can not block illumination beam; Under the prerequisite identical with condenser installation site in the present embodiment, in the detector of prior art, condenser meeting illumination beam creates and blocks, therefore, by the brachymemma of forward scattering condenser in Fig. 8 C and Fig. 8 D; Unobstructed to illumination beam for back scattering condenser, do not need to carry out Exception handling.
In optical analogy process, adopt one section of cylindrical side surface to be used for the light of simulation smoke particle scattering as the light that surface source of light is launched, in fig. 8, launch 10000 light by surface source of light, the rink corner of light is distributed as the luminous field pattern of lambert.
In Fig. 8 A and Fig. 8 C, can find out according to the distribution range of light and ray density, compared to the detector of prior art, the forward scattering condenser of the present embodiment detector can receive wider light and more light, and forward scattering condenser has screening effect to the light received, the light that namely forward scattering condenser receives all belongs to forward scattering light.
In Fig. 8 B and Fig. 8 D, can find out according to the distribution range of light and ray density, compared to the detector of prior art, the amount of light that the back scattering condenser of the present embodiment detector receives is less, but, the light that the back scattering condenser of the present embodiment detector receives all belongs to back scattering light, and back scattering condenser has significant light screening effect; In the detector of prior art, although back scattering condenser receives more light, have wherein a part of light to be forward scattering light, this is unfavorable for the design of probe algorithm and the raising of detection degree of accuracy and detection sensitivity.
In the scatter-type fire smog detector that the present embodiment proposes, by adopting above-mentioned scatter-type fire smog detector condenser, improve the capacity gauge of condenser to scattered beam, add the scattered beam quantity that optical receiver component receives, add the signal level of optical receiver component, increase signal to noise ratio (S/N ratio), thus improve the detection sensitivity of fire smog detector and detect degree of accuracy.
The above; be only the present invention's preferably embodiment; but protection scope of the present invention is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the present invention discloses; be equal to according to technical scheme of the present invention and inventive concept thereof and replace or change, all should be encompassed within protection scope of the present invention.