Gas concentration detection device

Abstract

The utility model discloses a gas concentration detection device, which comprises a light source, a detector, a chopper wheel and a measurement gas chamber, the chopper wheel is arranged between the light source and the detector, the chopper wheel can rotate relative to the light source, the chopper wheel comprises a first wheel disc, a second wheel disc and an optical filter, the first wheel disc and the second wheel disc are connected and clamp the optical filter together, the first wheel disc comprises a first filtering hole, the second wheel disc comprises a second filtering hole, the first filtering hole and the second filtering hole both face the optical filter, and the measuring gas chamber is used for containing gas to be measured. The measuring air chamber is arranged between the chopper wheel and the detector, and the optical signal emitted by the light source is irradiated to the detector after passing through the optical filter and the measuring air chamber. The chopper wheel provided by the utility model is simple in structure, and the optical filter is firmly installed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of gas concentration detection devices, belong to gas detection technical field. BACKGROUND

[0002] Gas concentration detection device includes light source assembly, detector assembly, optical path assembly, motor and chopping wheel assembly, etc., chopping wheel assembly includes chopping wheel and chopping wheel sensor.In optical application, chopping wheel rotates at fixed frequency, periodically blocks light beam, converts continuous light signal into alternating signal, which is convenient for subsequent lock-in amplification processing.

[0003] In related art, chopping wheel includes wheel disc, wheel disc front cover, wheel disc rear cover and optical filter, wheel disc front cover and wheel disc rear cover are tightly attached to the two sides of wheel disc respectively, wheel disc includes filter hole, wheel disc front cover includes front light transmission hole, wheel disc rear cover includes rear light transmission hole, optical filter is installed in filter hole, and the structure of chopping wheel is complex, which increases cost. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a kind of concentration detection device of gas with simple structure.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0006] A kind of gas concentration detection device, comprising:

[0007] Light source, the light source is used to emit light signal;

[0008] Detector, the detector is used to sense the light signal and output after converting the light signal into electrical signal;

[0009] Chopping wheel, the chopping wheel is located between the light source and the detector, the chopping wheel can rotate relative to the light source, the chopping wheel includes first wheel disc, second wheel disc and optical filter, the first wheel disc is connected with the second wheel disc and holds the optical filter together, the first wheel disc includes first filter hole, the second wheel disc includes second filter hole, and the first filter hole and the second filter hole are all towards the optical filter;And

[0010] Measurement gas chamber, the measurement gas chamber is used to accommodate measured gas, the measurement gas chamber is arranged between the chopping wheel and the detector, and the light signal emitted by the light source is irradiated to the detector after passing through the optical filter and the measurement gas chamber.

[0011] As a further improved technical solution of the utility model, the first wheel disc and the second wheel disc are both disc structures, the first wheel disc includes a plurality of first filter holes, and the second filter hole and the optical filter are both arranged correspondingly with the first filter hole.

[0012] As a further improved technical scheme of the utility model, the gas concentration detection device includes a driving member, the driving member includes an output shaft, the first wheel disc includes a first mounting hole, the second wheel disc includes a second mounting hole, and the output shaft is arranged in the first mounting hole and the second mounting hole.

[0013] As a further improved technical scheme of the utility model, the first mounting hole and the second mounting hole are both circular holes, and the inner diameter of the second mounting hole is greater than that of the first mounting hole.

[0014] As a further improved technical scheme of the utility model, the first wheel disc includes a plurality of first weight reduction holes, the plurality of first weight reduction holes are arranged around the first mounting hole, and the plurality of first weight reduction holes are exposed to the second mounting hole.

[0015] As a further improved technical scheme of the utility model, the second wheel disc includes a plurality of second weight reduction holes, and the second weight reduction holes are arranged between any two adjacent first filter holes.

[0016] As a further improved technical scheme of the utility model, the first wheel disc and the second wheel disc are welded and fixed.

[0017] As a further improved technical scheme of the utility model, the gas concentration detection device includes a test sensor, the test sensor is located on the side of the chopping wheel away from the driving member and is connected with the output shaft, and the test sensor is used for testing the number of revolutions of the chopping wheel.

[0018] As a further improved technical scheme of the utility model, the two ends of the measuring gas chamber are both provided with window pieces.

[0019] As a further improved technical scheme of the utility model, the measuring gas chamber is provided with a first gas nozzle and a second gas nozzle, the first gas nozzle is arranged close to the light source, the second gas nozzle is arranged close to the detector, the first gas nozzle is used for air inlet, and the second gas nozzle is used for air outlet.

[0020] Compared with the prior art, the chopping wheel provided by the utility model includes a first wheel disc, a second wheel disc and a filter, the first wheel disc is connected with the second wheel disc and jointly clamps the filter, and the chopping wheel not only has a simple structure, but also has firm filter installation. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is the front view of the gas detection device of the utility model;

[0022] Figure 2 is Figure 1 the side view of the chopping wheel in the middle;

[0023] Figure 3 yes Figure 1 Side view of the other side of the central chopper wheel;

[0024] Figure 4 yes Figure 2 Side view of the first roulette wheel;

[0025] Figure 5 yes Figure 3 Side view of the second wheel in the middle;

[0026] Figure 6 yes Figure 1 Side view of the detector. Detailed Implementation

[0027] The exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. If several embodiments exist, features in these embodiments may be combined with each other without conflict. When the description refers to the drawings, unless otherwise stated, the same numbers in different drawings represent the same or similar elements. The descriptions in the following exemplary embodiments do not represent all embodiments consistent with the present invention; rather, they are merely examples of apparatuses, products, and / or methods consistent with some aspects of the present invention as set forth in the claims.

[0028] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of protection of this invention. The singular forms “a,” “the,” or “the” used in the specification and claims of this invention are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0029] It should be understood that the terms "first," "second," and similar words used in the specification and claims of this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish the features. Similarly, the terms "an" or "a" do not indicate a quantity limitation, but rather indicate the presence of at least one. Unless otherwise stated, the terms "before," "after," "upper," "lower," and similar words appearing in this utility model are for ease of explanation only and are not limited to a specific location or spatial orientation. The terms "comprising" or "including" are an open-ended expression, meaning that the element preceding "comprising" or "including" covers the element following "comprising" or "including" and its equivalents, which does not exclude that the element preceding "comprising" or "including" may also include other elements. In this utility model, the word "several" means two or more.

[0030] Please refer to Figures 1 to 6As shown, this utility model discloses a gas concentration detection device, including a light source 1, a detector 2, a chopper 3, and a measuring gas chamber 4. The light source 1 emits light signals, such as infrared light. The light source 1 can be a small light bulb or a MEMS light source. The light signal emitted by the light source 1 illuminates the optical path, and the detector 2 performs infrared detection on the gas to be measured in the optical path, then converts the light signal into an electrical signal for output. That is, the detector 2 senses the light signal and converts it into an electrical signal for output. The chopper 3 is located between the light source 1 and the detector 2, and the chopper 3 can rotate relative to the light source 1. The chopper 3 rotates at a fixed frequency, periodically blocking the light beam, converting the continuous light signal into an alternating signal, facilitating subsequent phase-locked amplification. The chopper 3 modulates the DC or slowly varying signal into a high-frequency AC signal, avoiding low-frequency noise interference. The chopper 3 simultaneously generates a reference signal synchronized with the modulation frequency, used to lock the amplifier for synchronous demodulation and extract the effective signal. The chopper wheel 3 includes a first disc 31, a second disc 32, and a filter 33. The first disc 31 and the second disc 32 are connected and together clamp the filter 33. The chopper wheel 3 has a simple structure, and the filter 33 is securely installed. The first disc 31 includes a first filter hole 311, and the second disc 32 includes a second filter hole 321. Both the first filter hole 311 and the second filter hole 321 face the filter 33 to allow light signals to pass through. The measuring gas chamber 4 is used to contain the gas to be measured. The measuring gas chamber 4 is located between the chopper wheel 3 and the detector 2. The light signal emitted by the light source 1 passes through the filter 33 and the measuring gas chamber 4 before illuminating the detector 2.

[0031] Both the first disc 31 and the second disc 32 are circular structures. The first disc 31 includes a plurality of first filter holes 311, which are evenly arranged along the circumference of the first disc 31. Correspondingly, the second filter holes 321 and the filter 33 are respectively provided with corresponding first filter holes 311. Please refer to the embodiments illustrated in the figures of this utility model. Figure 2 and Figure 4 As shown, the first wheel 31 includes three first filter holes 311, and the shape of the first filter holes 311 is square. Of course, in other embodiments, the shape of the first filter holes 311 can also be trapezoidal or circular.

[0032] In some embodiments, the first disc 31 and the second disc 32 are welded together, which not only improves the connection stability between the first disc 31 and the second disc 32, but also stabilizes the filter 33 between the first disc 31 and the second disc 32, preventing the filter 33 from falling off when the chopper 3 rotates at high speed.

[0033] Please refer to Figure 1 As shown, the gas concentration detection device includes a drive unit 5, which can be a motor, and includes an output shaft 51. Please refer to... Figures 2 to 5As shown, the first disc 31 includes a first mounting hole 312, and the second disc 32 includes a second mounting hole 322. The output shaft 51 passes through the first mounting hole 312 and the second mounting hole 322, achieving a fixed connection between the chopper 3 and the output shaft 51. Specifically, both the first mounting hole 312 and the second mounting hole 322 are circular holes, with the inner diameter of the second mounting hole 322 being larger than that of the first mounting hole 312. The first mounting hole 312 of the chopper 3 is connected to the output shaft 51, while the second mounting hole 322 is not in contact with the output shaft 51. Increasing the inner diameter of the second mounting hole 322 helps to reduce weight.

[0034] Please refer to Figure 2 and Figure 4 As shown, the first wheel 31 includes a plurality of first weight-reducing holes 313, which are arranged around the first mounting hole 312 and exposed in the second mounting hole 322. By providing a plurality of first weight-reducing holes 313, a weight-reducing effect is achieved.

[0035] The second disc, number 32, has a circular structure; please refer to [the relevant documentation]. Figure 3 and Figure 5 As shown, the second wheel 32 includes multiple second weight-reducing holes 323, with a second weight-reducing hole 323 provided between any two adjacent first filter holes 311. The area of ​​the first wheel 31 corresponding to the second weight-reducing holes 323 does not have weight-reducing holes; instead, a ring of first weight-reducing holes 313 is provided outside the first mounting hole 312, achieving staggered weight reduction between the first wheel 31 and the second wheel 32. In the embodiment illustrated in this utility model, the second wheel 32 includes three second weight-reducing holes 323, with a second weight-reducing hole 323 provided between any two adjacent first filter holes 311.

[0036] Please refer to Figure 1 As shown, the gas concentration detection device includes a test sensor 6, which is located on the side of the chopper 3 away from the drive component 5 and connected to the output shaft 51. The test sensor 6 is used to test the number of rotations of the chopper 3.

[0037] Please refer to Figure 1 As shown, both ends of the measuring chamber 4 are provided with windows 7 for light transmission and sealing. The measuring chamber 4 is provided with a first air nozzle 81 and a second air nozzle 82. The first air nozzle 81 is located near the light source 1, and the second air nozzle 82 is located near the detector 2. Specifically, the first air nozzle 81 is used for air intake, and the second air nozzle 82 is used for air exhaust.

[0038] The chopper wheel 3 provided by this utility model is disc-shaped, with a filter 33 embedded in the middle of the chopper wheel 3, and the chopper wheel 3 is placed on the light source side. When the chopper wheel 3 is driven by the driving component 5 to rotate to the filter 33, the light signal can pass through the filter 33 and be received by the detector 2, which can facilitate the rapid cutting of the light signal. In addition, according to the structure of the chopper wheel 3, the chopping frequency can be increased to achieve fast signal tracking and improve the sensor reading response time.

[0039] The above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. The understanding of the present utility model should be based on those skilled in the art. Although the present utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present utility model. All technical solutions and improvements that do not depart from the spirit and scope of the present utility model should be covered within the scope of the claims of the present utility model.

Claims

1. A gas concentration detection device, characterized in that, include: Light source (1), the light source (1) is used to emit light signals; Detector (2), the detector (2) is used to sense the optical signal and convert the optical signal into an electrical signal and output it; A chopper wheel (3) is located between the light source (1) and the detector (2). The chopper wheel (3) is rotatable relative to the light source (1). The chopper wheel (3) includes a first disc (31), a second disc (32), and a filter (33). The first disc (31) and the second disc (32) are connected and together hold the filter (33). The first disc (31) includes a first filter hole (311), and the second disc (32) includes a second filter hole (321). Both the first filter hole (311) and the second filter hole (321) face the filter (33). The measuring gas chamber (4) is used to contain the gas to be measured. The measuring gas chamber (4) is located between the chopper (3) and the detector (2). The light signal emitted by the light source (1) passes through the filter (33) and the measuring gas chamber (4) and then shines on the detector (2).

2. The gas concentration detection device as described in claim 1, characterized in that, Both the first wheel (31) and the second wheel (32) are disc structures. The first wheel (31) includes a plurality of first filter holes (311), and the second filter holes (321) and the filter (33) are all arranged corresponding to the first filter holes (311).

3. The gas concentration detection device as described in claim 2, characterized in that, The gas concentration detection device includes a drive component (5), the drive component (5) includes an output shaft (51), the first wheel (31) includes a first mounting hole (312), the second wheel (32) includes a second mounting hole (322), and the output shaft (51) passes through the first mounting hole (312) and the second mounting hole (322).

4. The gas concentration detection device as described in claim 3, characterized in that, Both the first mounting hole (312) and the second mounting hole (322) are round holes, and the inner diameter of the second mounting hole (322) is larger than the inner diameter of the first mounting hole (312).

5. The gas concentration detection device as described in claim 4, characterized in that, The first wheel (31) includes a plurality of first weight-reducing holes (313) arranged around the first mounting hole (312) and the plurality of first weight-reducing holes (313) exposed to the second mounting hole (322).

6. The gas concentration detection device as described in claim 4, characterized in that, The second wheel (32) includes a plurality of second weight reduction holes (323), and a second weight reduction hole (323) is provided between any two adjacent first filter holes (311).

7. The gas concentration detection device according to any one of claims 1 to 6, characterized in that, The first wheel (31) is welded and fixed to the second wheel (32).

8. The gas concentration detection device as described in claim 3, characterized in that, The gas concentration detection device includes a test sensor (6), which is located on the side of the chopper wheel (3) away from the drive member (5) and connected to the output shaft (51). The test sensor (6) is used to test the number of rotations of the chopper wheel (3).

9. The gas concentration detection device as described in claim 1, characterized in that, Both ends of the measuring chamber (4) are provided with window plates (7).

10. The gas concentration detection device as described in claim 1, characterized in that, The measuring air chamber (4) is provided with a first air nozzle (81) and a second air nozzle (82). The first air nozzle (81) is located near the light source (1), and the second air nozzle (82) is located near the detector (2). The first air nozzle (81) is used for air intake, and the second air nozzle (82) is used for air exhaust.

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