CN205643092U - Dust concentration sensor - Google Patents

Abstract

The utility model is suitable for a suspended particles concentration detection device field provides dust concentration sensor in the gas, and it includes the laser sensor body, is equipped with air inlet, gas outlet on the laser sensor body and feeds through the ventiduct between air inlet and gas outlet, and the ventiduct has photosensitive measuring position, still is equipped with the current -limiting structure in the ventiduct, and the current -limiting structure lies in between air inlet and the photosensitive measuring position and is close to photosensitive measuring position setting. The utility model discloses a photosensitive measuring position the place ahead at the ventiduct sets up a current -limiting structure, thereby can form a current -limiting passageway in the place ahead at photosensitive measuring position, the air current is because the inertia effect after flowing through the current -limiting passageway, can continue to keep to concentrate the state through photosensitive measuring position, make air current concentration degree when flowing through photosensitive measuring position improve, thus, the dust granule quantity that is detected had both been increased, can not increase parietal reflection parasitics light in the laser sensor body again, dust concentration sensor's detection accuracy has been improved.

Description

Dust concentration sensor

Technical field

This utility model belongs to concentration of suspended particles detection device field in gas, particularly relates to dust concentration and passes Sensor.

Background technology

Laser dust concentration sensor is to utilize MIE scattering theory that particle in air is carried out count measurement Or the sensor that mass concentration is measured, it generally comprises a ventilating duct, a LASER Discharge Tube and one Photo-sensitive cell.Its operation principle is: the air-flow entering laser dust concentration sensor flows along ventilating duct, Being irradiated by laser when flowing through above photo-sensitive cell and produce scattered light, photo-sensitive cell receives scattered light, passes through The analysis of scattered light i.e. can be obtained the dust concentration situation flowing through in photo-sensitive cell overhead stream.

In prior art, air-flow freely flows through above photo-sensitive cell along ventilating duct, so, is detected Dust concentration situation can be affected by ventilating duct width, so, if the width of ventilating duct is the widest, examine A large amount of particle can be lost during survey, thus the accuracy in detection of serious laser dust concentration sensor；If it is and logical Scattered light on the width too narrow then laser dust concentration sensor inwall in air channel strengthens, and then can cause veiling glare Increase, and the increase of veiling glare also influences whether the accuracy in detection of laser dust concentration sensor.

Utility model content

The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art, it is provided that dust concentration sensor, Which solve existing laser dust concentration sensor when detecting air-flow dust concentration due to by ventilating duct width Impact causes the technical problem of its accuracy in detection difference.

For reaching above-mentioned purpose, the technical solution adopted in the utility model is: dust concentration sensor, including Laser sensor body, described laser sensor body is provided with air inlet, gas outlet and enters described in being communicated in Ventilating duct between QI KOU and described gas outlet, described ventilating duct has photosensitive detection position, described ventilating duct Inside be additionally provided with flow restriction, described flow restriction between described air inlet and described photosensitive detection position also Arrange near described photosensitive detection position.

Alternatively, described laser sensor body includes having inner chamber, described air inlet, described gas outlet Main casing and be located at the Laser emission assembly of described interior intracavity, photo-sensitive cell, circuit board, described interior intracavity limits Surely having described ventilating duct, described photo-sensitive cell to be positioned at described ventilating duct, described Laser emission assembly is towards institute Stating photosensitive detection position and launch laser beam, described flow restriction is located on described Laser emission assembly or is located at On described main casing.

Alternatively, described Laser emission assembly includes mounting seat, the Laser emission being installed in described mounting seat Managing and be located at the condenser lens of described LASER Discharge Tube front end, described mounting seat includes pedestal and from described pedestal Top extends the extension board being convexly equipped in described pedestal front, described extension board runs through and is provided with and described photosensitive unit Part just relative to detection hole, described flow restriction is that the current limliting plate of described extension board side is located in bending.

Alternatively, described pedestal is provided with the appearance housing location for described LASER Discharge Tube and described condenser lens Chamber and the louvre connected with described cavity volume.

Alternatively, described pedestal has the tail end away from described extension board, and described louvre is near described tail end Arrange.

Alternatively, described interior intracavity is further defined with snapping in the draw-in groove of location for described Laser emission assembly, described Draw-in groove has the two groove sidewalls being oppositely arranged, described pedestal be designed with institute towards the sidepiece of groove sidewall described in two Stating louvre, one of them described groove sidewall is located between described gas outlet and described draw-in groove and on this groove sidewall It is provided with the dissipating vias for connecting described gas outlet and the described louvre near this groove sidewall.

Alternatively, described flow restriction has the ventilation section metering hole less than described ventilating duct ventilation section.

Alternatively, described laser sensor body has the first sidepiece and the second sidepiece that interval is oppositely arranged, Described first sidepiece is located at by described air inlet, and described second sidepiece, described ventilating duct bag are located in described gas outlet Include along parallel described first sidepiece extend the first ventilation unit and bending be located at described first ventilation unit one end and from The second ventilation unit that described first sidepiece extends towards described gas outlet.

Alternatively, the angle enclosing formation between described first ventilation unit and described second ventilation unit is obtuse angle, institute State and between the second ventilation unit and described gas outlet, be provided with a light barrier, leading to away from described first of described light barrier The position in wind portion is provided with several for the air-vent connecting described second ventilation unit and described gas outlet.

Alternatively, described laser sensor this most internal be additionally provided with for detect described laser sensor this most internal it The critesistor of ambient temperature.

The dust concentration sensor that this utility model provides, is set by the front, photosensitive detection position at ventilating duct Putting a flow restriction, thus can form a restricted flow passage in the front at photosensitive detection position, air-flow is flowing through limit Due to effect of inertia after circulation road, may proceed in the way of keeping collected state by photosensitive detection position and Scatter again after flowing through photosensitive detection position so that air-flow concentration degree when flowing through photosensitive detection position improves, this Sample, had both added the dust granule quantity being detected, will not increase again laser sensor chamber body wall Reflection veiling glare, improves the accuracy in detection of dust concentration sensor dramatically.

Accompanying drawing explanation

Fig. 1 is the Laser emission assembly assembling schematic diagram one with drain pan of this utility model embodiment offer；

Fig. 2 is the Laser emission assembly assembling schematic diagram two with drain pan of this utility model embodiment offer；

Fig. 3 is the schematic diagram of the airflow passes position limiting structure that this utility model embodiment provides；

Fig. 4 is the structural representation one of the mounting seat that this utility model embodiment provides；

Fig. 5 is the structural representation two of the mounting seat that this utility model embodiment provides；

Fig. 6 is the generalized section of the Laser emission assembly that this utility model embodiment provides；

Fig. 7 is critesistor, Laser emission assembly, blower fan and the drain pan that this utility model embodiment provides Fitting plane schematic diagram；

Fig. 8 is the overall assembling schematic diagram of the laser sensor body that this utility model embodiment provides；

Fig. 9 is the decomposing schematic representation of the dust concentration sensor that this utility model embodiment provides；

Figure 10 is critesistor, Laser emission assembly, photo-sensitive cell and the electricity that this utility model embodiment provides The fitting plane schematic diagram of road plate；

Figure 11 is the structural representation of the top cover that this utility model embodiment provides.

Detailed description of the invention

In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with accompanying drawing And embodiment, this utility model is further elaborated.Should be appreciated that described herein specifically Embodiment, only in order to explain this utility model, is not used to limit this utility model.

It should be noted that when an element is described as " being fixed on " or " being arranged at " another element Time upper, it can be directly on another element or may be simultaneously present centering elements.When an element quilt Being depicted as " connection " another element, it can be to be directly connected to another element or may deposit simultaneously At centering elements.

Also, it should be noted the orientation term such as left and right, upper and lower, top in following example, end, It is only relative concept or with the normal operating condition of product as reference each other, and should not be regarded as having Restrictive.

As shown in figs. 1-11, the dust concentration sensor that this utility model embodiment provides, including laser sensing Device body 1, laser sensor body 1 is provided with air inlet 101, gas outlet 102 and is communicated in air inlet Ventilating duct 103 between 101 and gas outlet 102, ventilating duct 103 has photosensitive detection position, ventilating duct Be additionally provided with flow restriction 10 in 103, flow restriction 10 between air inlet 101 and photosensitive detection position also Arrange near photosensitive detection position, i.e. flow restriction 10 is positioned at the front at photosensitive detection position along air flow direction, Air-flow, after air inlet 101 enters in ventilating duct 103, can first flow through flow restriction 10 and pass through photosensitive detection Position.The dust concentration sensor that this utility model embodiment provides, by the photosensitive inspection at ventilating duct 103 Survey front, position and one flow restriction 10 is set, thus a current limliting can be formed in the front at photosensitive detection position and lead to Road, air-flow due to effect of inertia, may proceed to pass through in the way of keeping collected state after flowing through restricted flow passage Also scatter after flowing through photosensitive detection position in photosensitive detection position so that air-flow is flowing through photosensitive detection position again Time concentration degree improve, dust loss is greatly decreased, and so, has both added the dust granule number being detected Amount, will not increase again the reflection veiling glare of laser sensor body 1 internal chamber wall, improve dust dramatically The accuracy in detection of concentration sensor.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 3 and Fig. 4, flow restriction 10 has ventilation section and is less than The metering hole 100 of ventilating duct 103 ventilation section.During airflow passes metering hole 100, concentration degree improves, and Due to effect of inertia, air-flow also can keep collected state when metering hole 100 flows through photosensitive detection position, Scatter further along behind photosensitive detection position, thus, give vent to anger width narrow into gas can be formed at photosensitive detection position Structure so that detection air-flow concentration degree improve, dust loss is greatly decreased, and improves the inspection of product Survey sensitivity.

Preferably, in the lump with reference to shown in Fig. 7, Fig. 9 and Figure 10, be provided with in laser sensor body 1 for The critesistor 15 of the ambient temperature in detection laser sensor body 1.Herein, by laser sensor Set up critesistor 15 in body 1, so, laser sensor can be detected in real time originally by critesistor 15 Ambient temperature in body 1, thus be beneficial to be adjusted according to actual environment temperature, revise dust concentration sensing The output result of device, efficiently solve dust concentration sensor because of Laser emission assembly 12 the most defeated Go out power difference and cause the technical problem that dust concentration sensor outputs accuracy is low.

Preferably, critesistor 15 is convex to be exposed in ventilating duct 103, so, and can be real by critesistor 15 Time detection ventilating duct 103 in air themperature, thus be beneficial to improve further the temperature that critesistor 15 detects The accurate reliability of degree.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 7, Fig. 8 and Fig. 9, laser sensor body 1 includes tool Have inner chamber, air inlet 101, the main casing 11 of gas outlet 102 and be located at interior intracavity Laser emission assembly 12, Photo-sensitive cell 13, circuit board 14；Interior intracavity defines ventilating duct 103, photo-sensitive cell 13 and photosensitive detection Position is that upper and lower para-position is arranged, and the position with photo-sensitive cell about 13 para-position setting of ventilating duct 103 is light Quick detection position, Laser emission assembly 12 is towards photosensitive detection position transmitting laser beam, and flow restriction 10 sets On Laser emission assembly 12 or be located on main casing 11.Laser emission assembly 12, photo-sensitive cell 13, Circuit board 14 and critesistor 15 are all located at interior intracavity, Laser emission assembly 12, photo-sensitive cell 13 and heat Quick resistance 15 is all electrically connected with circuit board 14, and Laser emission assembly 12 can be under the control of circuit board 14 Send out laser beam；Its detection information can be fed back to circuit board 14 by photo-sensitive cell 13 and critesistor 15 On, and the detection information fed back photo-sensitive cell 13 and critesistor 15 by circuit board 14 processes backward Outer output detections result.The setting of flow restriction 10, concentration degree when can make airflow passes photosensitive detection position Improving, dust loss is greatly decreased, thus improves the detection sensitivity of product.

Preferably, in the lump with reference to shown in Fig. 1-6, Laser emission assembly 12 includes mounting seat 121, is installed on LASER Discharge Tube 122 in mounting seat 121 and the condenser lens 123 being located at LASER Discharge Tube 122 front end, Mounting seat 121 includes pedestal 1211 and extends the extension being convexly equipped in pedestal 1211 front from pedestal 1211 top Plate 1212, extension board 1212 runs through be provided with photo-sensitive cell 13 just relative to detection hole 12121, ventilate The position with the para-position setting of detection hole about 12121 in road 103 is photosensitive detection position, flow restriction 10 Be located at the current limliting plate of extension board 1212 side for bending, metering hole 100 runs through to be located on current limliting plate.This Place, the plate that flow restriction 10 is set in mounting seat 121, its simple in construction, easily fabricated, and The installation procedure of flow restriction 10 can be saved.Photo-sensitive cell 13 and Laser emission assembly 12 are installed on circuit board After the lower surface of 14, photo-sensitive cell 13 is vertically positioned at circuit board 14 lower surface and detection hole Between 12121, when Laser emission assembly 12 sends out laser beam, detection hole 12121 be positioned at laser beam with Between photo-sensitive cell 13, and the laser beam that Laser emission assembly 12 sends is along the side parallel with photo-sensitive cell 13 Formula is irradiated in light trapping chamber 107 from the underface in detection hole 12121 and photo-sensitive cell 13.Detection hole 12121 Setting, be beneficial to ensure that photo-sensitive cell 13 can effectively detect and produce when laser beam irradiation crosses ventilating duct 103 Scattered information, thus it is dense to flowing through dust in the air-flow of ventilating duct 103 to be beneficial to realize laser sensor body 1 The detection function of degree.The setting of condenser lens 123, converges for the laser beam sent by Laser emission assembly 12 Gather in detection hole 12121 and the underface of photo-sensitive cell 13.

Preferably, in the lump with reference to shown in Fig. 1-5, pedestal 1211 is provided with for LASER Discharge Tube 122 and focusing The accommodating cavity volume 12111 positioned of lens 123 and the louvre 12112 connected with cavity volume 12111.Louvre The setting of 12112 so that the heat produced when LASER Discharge Tube 122 works can distribute, effectively in time Improve the radiating effect of LASER Discharge Tube 122, be beneficial to ensure the service life of LASER Discharge Tube 122.

Preferably, pedestal 1211 has the tail end away from extension board 1212, and the tail end of pedestal 1211 is near going out QI KOU 102, louvre 12112 is arranged near tail end.Herein, by the position of louvre 12112 is entered Row optimal design-aside, both can improve the radiating effect of LASER Discharge Tube 122, again will not be to the accuracy of detection of product Produce impact.

Preferably, seeing figures.1.and.2 in the lump shown, interior intracavity is further defined with for Laser emission assembly 12 Snapping in the draw-in groove 104 of location, draw-in groove 104 has the two groove sidewalls being oppositely arranged, pedestal 1211 towards two The sidepiece of groove sidewall is designed with louvre 12112, and one of them groove sidewall is located at gas outlet 102 and draw-in groove 104 Between and this groove sidewall be provided with for connecting gas outlet 102 and the louvre 12112 near this groove sidewall Dissipating vias 105.The setting of draw-in groove 104, can be beneficial to improve Laser emission assembly 12 further at laser The steadiness installed in sensor body 1.The setting of dissipating vias 105 so that LASER Discharge Tube 122 works The partial heat given out can discharge through dissipating vias 105, gas outlet 102 from louvre 12112, Its excellent in heat dissipation effect.

Preferably, with reference to shown in Fig. 6, preposition diaphragm opening 12113 and rearmounted diaphragm in pedestal 1211, it are additionally provided with Hole 12114, rearmounted diaphragm opening 12114 is between preposition diaphragm opening 12113 and cavity volume 12111.Herein, Carry out limiting the beam size of laser beam by preposition diaphragm opening 12113 and rearmounted diaphragm opening 12114, can profit In reducing scattering of light and interference.

Preferably, the power of LASER Discharge Tube 122 is 3mw～5mw, and the external diameter of LASER Discharge Tube 122 is 5mm～8mm, for this LASER Discharge Tube 122, uses condenser lens 123 that laser beam is converged in 15mm's Position, now spot size and the angle of divergence size of test point is in suitably value, so that laser sensing Accuracy and the stability of the value that device body 1 measurement obtains can be more preferably.As the present embodiment one is the most concrete Embodiment, LASER Discharge Tube 122 selects external diameter to be 6mm, power is 3.6mw, wavelength is swashing of 650nm Light-emitting tube 122.Of coursing, in concrete application, the parameter value of LASER Discharge Tube 122 is not limited to this.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 2 and Fig. 7, laser sensor body 1 has interval phase To the first sidepiece arranged and the second sidepiece, air inlet 101 is located at the first sidepiece, and gas outlet 102 is located at the Two sidepieces, ventilating duct 103 includes that the first ventilation unit 1031 and the bending that extend along parallel first sidepiece are located at the One ventilation unit 1031 one end and the second ventilation unit 1032 extended towards gas outlet 102 from the first sidepiece.This Place, the first sidepiece and the second sidepiece are respectively front side portion and the rear lateral portion of laser sensor body 1.Herein, First ventilation unit 1031 and the second ventilation unit 1032 connect formation one substantially L-shaped structure, so, phase For existing U-shaped ventilating duct 103, can effectively reduce gas and flow to gas outlet 102 from air inlet 101 Flow through distance, thus be beneficial to improve the detection sensitivity of dust concentration sensor.

Preferably, the angle enclosing formation between the first ventilation unit 1031 and the second ventilation unit 1032 is obtuse angle, So, can effectively reach to reduce air and flow to the gas outlet 102 and his like the purpose through distance from air inlet 101. Of coursing, the angle enclosing formation between the first ventilation unit 1031 and the second ventilation unit 1032 is alternatively right angle, Or, the transition turning between the first ventilation unit 1031 and the second ventilation unit 1032 can be smooth arc shape.

Preferably, in the lump shown in reference Fig. 1, Fig. 2 and Fig. 7, the second ventilation unit 1032 and gas outlet 102 Between be provided with a light barrier 110, the position away from the first ventilation unit 1031 of light barrier 110 is provided with several For connecting the air-vent 1101 of the second ventilation unit 1032 and gas outlet 102.In concrete application, flow into logical Air-flow in air channel 103 can flow at gas outlet 102 from air-vent 1101.Herein, by dust concentration The internal structure of sensor optimizes design further, can effectively prevent ambient from shining sense from gas outlet 102 Situation on optical element 13 occurs, thus is beneficial to improve further the accuracy of detection of dust concentration sensor.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 2 and Fig. 7, in laser sensor body 1, it is additionally provided with use In the light trapping chamber 107 of absorption laser beam, light trapping chamber 107 has the accent connected with ventilating duct 103, The convex windshied part being exposed in ventilating duct 103 of extension it is provided with at accent and in the position near air inlet 101 side. Draw-in groove 104 and light trapping chamber 107 are respectively arranged on the two opposing lateral sides of ventilating duct 103 corner, accent and card Groove 104 is just relative, and the laser beam that Laser emission assembly 12 is launched is irradiated into light trapping after ventilating duct 103 In chamber 107, photo-sensitive cell 13 is between Laser emission assembly 12 and light trapping chamber 107 and is positioned at ventilation In road 103.The setting of windshied part, gets around during the intersection of bootable airflow passes ventilating duct 103 and accent Light trapping chamber 107, thus the dust that effectively prevent in air-flow causes in accent entrance light trapping chamber 107 The phenomenon of light trapping chamber 107 dust stratification occurs, and then prevents owing to light trapping chamber 107 dust stratification causes laser ash Dust concentration sensor light noise increases, the bad phenomenon of output result misalignment occurs.

Preferably, the wall in the frontage and airiness road 103 of windshied part is arc-shaped curved surface, so, can make to keep out the wind Portion is mild to the guiding effectiveness comparison of air-flow, thus is beneficial to prevent air-flow from producing bigger impact at windshied part And the pressure loss.Of coursing, in concrete application, the shape of windshied part is not limited to this, such as: the court of windshied part Also tapered plane can be set to the wall of ventilating duct 103.

Specifically, the cavity wall in light trapping chamber 107 can use light absorbent to make, or, light trapping chamber 107 Cavity wall may be used without being formed by sub-optical processing again after non-light absorbent makes, both modes all can make Light trapping chamber 107 has the effect absorbing laser beam.

Preferably, in the lump with reference to shown in Fig. 7 and Fig. 9, laser sensor body 1 also includes being located at gas outlet 102 or air inlet 101 at blower fan 16.The setting of blower fan 16, is mainly used in as laser sensor body In 1, the flowing of air-flow provides and drives power.

Preferably, in the lump with reference to shown in Fig. 7, Fig. 9 and Figure 10, above-mentioned blower fan 16 is for being located at gas outlet Air exhauster 16 at 102, circuit board 14 is provided with and dodges breach 142 for dodge air exhauster 16, takes out Blower fan 16 is through dodging breach 142 and being installed at gas outlet 102, and air exhauster 16 is electrical with circuit board 14 Connecting, circuit board 14 can control air exhauster 16 startup optimization and out of service.During air exhauster 16 startup optimization, It forms negative pressure, so that extraneous air can be from air inlet 101 in making ventilating duct 103 in the way of bleeding Enter in laser sensor body 1, and final outflow at gas outlet 102 is swashed after ventilating duct 103 guides Outside optical sensor body 1.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 2, Fig. 8, Fig. 9 and Figure 11, main casing 11 includes the end Shell 111 and top cover 112, top cover 112 is covered on drain pan 111 and is connected formation with drain pan 111 to be had interior Chamber, air inlet 101, the main casing 11 of gas outlet 102.Herein, main casing 11 simple in construction, manufacturer Just and be beneficial to its internal part (internal part includes being located at the Laser emission assembly 12 of interior intracavity, photosensitive unit Part 13, critesistor 15 and circuit board 14 etc.) installation.

Specifically, in the lump with reference to shown in Fig. 7, Fig. 9 and Figure 10, circuit board 14 has towards drain pan 111 Bottom panel and top plate face towards top cover 112, Laser emission assembly 12, photo-sensitive cell 13 and heat Quick resistance 15 be all preferably attached to the bottom panel of circuit board 14, photo-sensitive cell 13 and critesistor 15 from The bottom panel of circuit board 14 extends convex being exposed in ventilating duct 103, so, is beneficial to improve the tight of product structure Gathering property, the air being beneficial to again ensure to enter in laser sensor body 1 can first pass through photo-sensitive cell 13 and temperature-sensitive Resistance 15 is just discharged outside laser sensor body 1.

Preferably, in the lump shown in reference Fig. 1, Fig. 2, Fig. 7, Fig. 8, Fig. 9 and Figure 11, air inlet 101 Being located on top cover 112, ventilating duct 103 is located on drain pan 111, and top cover 112 is provided with and air inlet 101 Laying respectively at the upper breach 1022 of the two opposing lateral sides of top cover 112, drain pan 111 is provided with and upper breach 1022 Para-position arranges and encloses the lower breach 1021 forming gas outlet 102 with upper breach 1022.Herein, by right The position of air inlet 101, gas outlet 102 and ventilating duct 103 is optimized setting, can beneficially reduce laser The volume of sensor body 1.

Preferably, the opening section area of air inlet 101 less than gas outlet 102 opening section area one Half, so it is beneficial to ensure the smoothness that air-flow flows in laser sensor body 1.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 7 and Fig. 8, drain pan 111 includes base plate 1110, header board 1111, back plate 1112, left plate 1113 and right panel 1114, header board 1111, back plate 1112, left plate 1113 The edge being arranged at base plate 1110 is bent respectively with right panel 1114.Lower breach 1021 is located at back plate The end near left plate 1113 of 1112, ventilating duct 103 is from the turning of header board 1111 with right panel 1114 Place extends at the medium position of left plate 1113, and header board 1111 and left plate 1113 are located in light trapping chamber 107 Corner, draw-in groove 104 is arranged at the centre of drain pan 111 in the mode forming 45 degree of angles with header board 1111 Position.

Preferably, in the lump with reference to shown in Fig. 1, Fig. 2 and Fig. 7, drain pan 111 also include the first dividing plate 1115, Second partition the 1116, the 3rd dividing plate the 1117, the 4th dividing plate the 1118, the 5th dividing plate 1119, the first dividing plate 1115 From the position of the close left plate 1113 of header board 1111, the inner side towards drain pan 11111 is bowing；The Two dividing plates 1116 bend towards the bowing end of the first dividing plate 1115 at left plate 1113 and extend, and second One end of dividing plate 1116 is connected in left plate 1113, the other end and the bowing end of the first dividing plate 1115 It is oppositely arranged in interval.The end that first dividing plate 1115 is relative with second partition 1116 forms light trapping chamber 107 Accent, the bowing end of the first dividing plate 1115 is above-mentioned windshied part, the first dividing plate 1115, Two dividing plates 1116, left plate 1113 and header board 1111 enclose the above-mentioned light trapping chamber 107 of formation jointly.3rd every Plate 1117 extends in drain pan 111 along the mode parallel with header board 1111 from right panel 1114, and the 3rd every Having spacing between end away from right panel 1114 and the left plate 1113 of plate 1117, light barrier 110 is from left plate The position of the close lower breach 1021 of 1113 is towards the end away from right panel 1114 of the 3rd dividing plate 1117 Bending extend, and one end of light barrier 110 be connected to back plate 1112 near lower breach 1021 position, The end away from right panel 1114 of the other end and the 3rd dividing plate 1117 is that interval is oppositely arranged, the 4th dividing plate 1118 from the 3rd dividing plate 1117 away from right panel 1114 end by with header board 1111 in 45 degree of angles in the way of Towards back to light trapping chamber 107 direction extend, the 5th dividing plate 1119 from light barrier 110 away from left plate 1113 End by with header board 1111 in 45 degree of angles in the way of towards back to light trapping chamber 107 direction extend, header board 1111, the first dividing plate 1115, second partition the 1116, the 3rd dividing plate 1117 and light barrier 110 enclose jointly Forming above-mentioned ventilating duct 103, the 4th dividing plate 1118 and the 5th dividing plate 1119 enclose the above-mentioned draw-in groove of formation jointly 104, the i.e. the 4th dividing plate 1118 and the 5th dividing plate 1119 form the above-mentioned two groove sidewalls of draw-in groove 104, the 5th every Plate 1119 is every the groove sidewall being located between draw-in groove 104 and gas outlet 102.

Preferably, the length of the 5th dividing plate 1119, more than the length of the 4th dividing plate 1118, so, can prevent 4th dividing plate 1118 blocks the louvre 12112 near it, thus is beneficial to fully ensure that LASER Discharge Tube 122 Radiating effect.

Preferably, in the lump with reference to shown in Figure 10 and Figure 11, top cover 112 includes 1121, four pieces of difference of top board The side plate 1122 of edge of top board 1121 is located in bending and bending be connected to two adjacent side plates 1122 and with This two adjacent side plates 1122 encloses the baffle plate 1123 forming air flowing lumen, and air inlet 101 is located at and is enclosed shape Become on one block of side plate 1122 of air flowing lumen 106, circuit board 14 runs through and is provided with for connecting air stream Cavity 106 and the passage 141 of ventilating duct 103.Air-flow enters air flowing lumen 106 from air inlet 101 In, after the barrier effect by baffle plate 1123, the flow direction of air-flow can be changed, flow at passage 141 In ventilating duct 103.After photo-sensitive cell 13 and critesistor 15 are all installed on the lower surface of circuit board 14, Critesistor 15 is positioned at passage 141 and photo-sensitive cell 13 along air-flow flow direction in ventilating duct 103 Between, i.e. air-flow first flows through critesistor 15 after passage 141 enters in ventilating duct 103 and passes through photosensitive Element 13, is so beneficial to preferably revise laser sensor body 1 according to the detected value of critesistor 15 Output result.

Preferably, in the lump with reference to shown in Fig. 1 and Fig. 9, above-mentioned dust concentration sensor also includes being packaged in External conductive casing 2 outside laser sensor body 1 and being electrically connected between circuit board 14 and external conductive casing 2 Ground wire, drain pan 111 runs through and is provided with the cable-through hole 108 worn for ground wire.External conductive casing 2 concretely by The shell 2 that conducting metal is made, which is provided with the air intake 21 arranged in inside and outside para-position with air inlet 101 and The air vent (not shown) arranged in inside and outside para-position with gas outlet 102.Herein, by ground wire by circuit board 14 are electrically connected with external conductive casing 2, can play the effect of shielding interference, thus be beneficial to improve dust The stability of concentration sensor.

The dust concentration sensor that this utility model embodiment provides, by setting in the front at photosensitive detection position Put a bit of restricted flow passage, so that air-flow directly flows through photosensitive detection position by after restricted flow passage, detection After further along side scatter so that detection air flow collection moderate improve, dust loss is greatly decreased, increase The sensitivity of detection.Additionally, it offers heat radiation by pedestal 1211 tail end at Laser emission assembly 12 Hole 12112, offer dissipating vias 105 at the tail end of the 4th dividing plate 1118, thus LASER Discharge Tube 122 can be made It is exposed, and the position being in close blower fan 16 is connected with gas outlet 102, thus play raising laser and send out Penetrate the effect of pipe 122 radiating effect.

The foregoing is only preferred embodiment of the present utility model, not in order to limit this utility model, All any amendment, equivalent or improvement etc. made within spirit of the present utility model and principle, all should Within being included in protection domain of the present utility model.

Claims (10)

1. dust concentration sensor, including laser sensor body, described laser sensor body be provided with into QI KOU, gas outlet and the ventilating duct being communicated between described air inlet and described gas outlet, described ventilation stage property There is photosensitive detection position, it is characterised in that: it is additionally provided with flow restriction, described flow restriction in described ventilating duct Arrange between described air inlet and described photosensitive detection position and near described photosensitive detection position.

2. dust concentration sensor as claimed in claim 1, it is characterised in that: described laser sensor is originally Body includes having inner chamber, described air inlet, the main casing of described gas outlet and be located at the laser of described interior intracavity Emitting module, photo-sensitive cell, circuit board, described interior intracavity defines described ventilating duct, described photo-sensitive cell Being positioned at described ventilating duct, described Laser emission assembly launches laser beam, institute towards described photosensitive detection position State flow restriction be located on described Laser emission assembly or be located on described main casing.

3. dust concentration sensor as claimed in claim 2, it is characterised in that: described Laser emission assembly The LASER Discharge Tube that including mounting seat, is installed in described mounting seat and be located at described LASER Discharge Tube front end Condenser lens, described mounting seat includes pedestal and extension is convexly equipped in described pedestal front from described pedestal top Extension board, described extension board runs through be provided with described photo-sensitive cell just relative to detection hole, described current limliting tie Structure is the current limliting plate that described extension board side is located in bending.

4. dust concentration sensor as claimed in claim 3, it is characterised in that: described pedestal is provided with confession Cavity volume that described LASER Discharge Tube houses location with described condenser lens and the louvre connected with described cavity volume.

5. dust concentration sensor as claimed in claim 4, it is characterised in that: described pedestal have away from The tail end of described extension board, described louvre is arranged near described tail end.

6. dust concentration sensor as claimed in claim 5, it is characterised in that: described interior intracavity is further defined by Having the draw-in groove snapping in location for described Laser emission assembly, described draw-in groove has the two groove sidewalls being oppositely arranged, Described pedestal be designed with described louvre towards the sidepiece of groove sidewall described in two, one of them described groove sidewall It is located between described gas outlet with described draw-in groove and this groove sidewall is provided with for connecting described gas outlet with close The dissipating vias of the described louvre of this groove sidewall.

7. the dust concentration sensor as described in any one of claim 1 to 6, it is characterised in that: described limit Flow structure has the ventilation section metering hole less than described ventilating duct ventilation section.

8. the dust concentration sensor as described in any one of claim 1 to 6, it is characterised in that: described sharp Optical sensor body has the first sidepiece and the second sidepiece that interval is oppositely arranged, and described air inlet is located at described First sidepiece, described gas outlet is located at described second sidepiece, and described ventilating duct includes along parallel described first side The first ventilation unit and bending that portion extends are located at described first ventilation unit one end and from described first sidepiece towards institute State the second ventilation unit that gas outlet extends.

9. dust concentration sensor as claimed in claim 8, it is characterised in that: described first ventilation unit with The angle enclosing formation between described second ventilation unit is obtuse angle, between described second ventilation unit and described gas outlet Being provided with a light barrier, the position away from described first ventilation unit of described light barrier is provided with several for connecting Described second ventilation unit and the air-vent of described gas outlet.

10. the dust concentration sensor as described in any one of claim 1 to 6, it is characterised in that: described This internal temperature-sensitive electricity being additionally provided with for detecting this internal ambient temperature of described laser sensor of laser sensor Resistance.