Patent Description:
A urea solution or a urea-based solution is often used in automobiles to reduce exhaust emissions. For example, some diesel-powered motor vehicles include a urea tank separated from the fuel tank. The urea tank is used for carrying a working fluid such as an automotive urea solution. The automotive urea solution is stored in the urea tank and injected into the exhaust of a vehicle to convert nitrogen oxides into basic nitrogen and water, thereby reducing harmful emissions from the vehicle.

The overall implementation of the National Standard IV and higher emission standards requires that all heavy-duty commercial vehicles must be equipped with an SCR system or an equivalent emission after-treatment device. Most of existing automobile manufacturers prefer the SCR system and thus urea is necessary. Only when it is ensured that the automobile urea solution is in a certain concentration range, can the oxide be fully converted into nitrogen and water. The excessive of concentration will cause secondary pollution of NH3. The lack of concentration cannot ensure that the emission standards are met. The use of tap water or sea water out of fraud or the adding of other solvents such as diesel oil by mistake may even cause damages to the expensive after-treatment system. With the enforcement of an on-board diagnostics (OBD) system, if the emission standards are not met or the quality and concentration of urea does not meet the requirements, the torque of the vehicle is limited and even the vehicle cannot be started. Therefore, with the implementation of Euro Vl standards, a quality sensor becomes a mandatory installation component. Based on the above situation, the precision of detecting the concentration of urea in a urea solution is very important.

A sensor for measuring a liquid is disclosed in the existing art.

The sensor includes: a light source operatively coupled to an inner chamber disposed in a liquid solution and configured to emit light and transmit the light to the inner chamber; a light detector operatively coupled to the inner chamber and configured to receive at least a portion of the light from the inner chamber; and a controller configured to determine a concentration or quality of the liquid solution on a basis of the light emitted by the light source and the portion of the light received by the light detector.

Although the above-mentioned sensor for measuring a liquid may measure the concentration of urea, factors affecting the testing precision in the urea concentration testing process cannot be eliminated. For example, bubbles in the solution to be tested cannot be eliminated in advance. If the solution to be tested is bubble-doped, the precision of testing the concentration of urea will be affected. Therefore, the result of testing the concentration of urea obtained by the above-mentioned solution has low reliability. Document <CIT> describes a method and apparatus for eliminating air in fluid samples continuously flowing through a closed turbidimeter instrument, wherein the fluid flowed at a predetermined rate is directed through an air trap zone isolated from the turbidity sensing zone, a fluid is maintained in the air trap zone by means of the flow rate for a sufficient time period and through an elongated path to remove air bubbles present in the fluid. Document <CIT> describes an apparatus for measuring water quality that is provided to simultaneously measure general property and turbidity of water to be measured. A protective cap with a turbidity measuring container for a water quality sensor is provided and comprises: a protection cap of which open upper end is mounted at a sensor holder to protect the sensor; and the container which is mounted inside the protective cap. The container comprise: an outer container with a first inlet hole formed between the upper and lower ends; and an inner container which is mounted inside the outer container.

According to the invention, there is provided an optical concentration testing device comprising an optical concentration sensor protective casing as defined with appended independent claim <NUM>. Preferred embodiments of the invention are defined with the dependent claims.

Embodiments of the present invention provide an optical concentration sensor protective casing to protect a sensor body from being damaged due to collision or squeeze to the sensor body, thereby prolonging the service life of the sensor body.

The embodiments of the present invention further provide an optical concentration sensor protective casing to make a solution to be tested inside the protective casing tend to be still, thereby improving the reliability of the testing result.

The embodiments of the present invention further provide an optical concentration testing device to effectively protect the sensor body, prolong the service life of the sensor body, and improve the testing precision.

The technical solutions provided by the embodiments of the present invention are described below.

According to one aspect and as further defined with claim <NUM>, an optical concentration sensor protective casing is provided, including an outer cover and a bubble isolation shield. The bubble isolation shield is embedded on an inner side of the outer cover.

The outer cover is provided with a convection hole.

The bubble isolation shield is provided with a liquid intake hole.

The outer cover and the bubble isolation shield may be both made of lightproof materials.

The protective casing may be arranged to protect the sensor body from being damaged due to collision or squeeze to the sensor body, thereby prolonging the service life of the sensor body.

As a technical solution of the optical concentration sensor protective casing, the protective casing further includes an air hole baffle plate. The outer cover is provided with a first exhaust hole, the air hole baffle plate covers the first exhaust hole, and an interstice exists between the air hole baffle plate and the first exhaust hole.

The optical concentration sensor protective casing includes a middle fixing frame, and may further include an upper fixing support, a lower fixing support, and a fixing ring. The outer cover and the bubble isolation shield are mounted at one end of the middle fixing frame, the fixing ring is mounted at the other end of the middle fixing frame, and the upper fixing support and the lower fixing support are nested on the outer sides of the middle fixing frame. The bubble isolation shield and the inner space of the middle fixing frame form a testing section for a solution to be tested.

The air hole baffle plate may be secured to the upper fixing support.

The air hole baffle plate is to the middle fixing frame.

The air hole baffle plate may be secured to the outer cover.

The air hole baffle plate may be disposed on the outer side of the first exhaust hole, so as to prevent the solution to be tested from directly entering the testing section through the first exhaust hole and prevent such pollutants as dust from entering the testing section through the first exhaust hole and affecting the precision of the testing result, thereby ensuring the reliability of the testing result.

As a technical solution of the optical concentration sensor protective casing, the bubble isolation shield is provided with a second exhaust hole, the first exhaust hole and the second exhaust hole intercommunicate.

The central axis of the first exhaust hole and the central axis of the second exhaust hole may be a same straight line.

The first exhaust hole and the second exhaust hole, which intercommunicate, may be provided for cross-ventilation between the testing section and the outside, thereby ensuring that the solution to be tested may enter the testing section.

As a technical solution of the optical concentration sensor protective casing, an obstacle is disposed between the convection hole and the liquid intake hole and the solution to be tested bypasses the obstacle from the convection hole to the liquid intake hole.

The obstacle may be disposed between the convection hole and the liquid intake hole, so that the solution to be tested needs to bypass the obstacle to reach the liquid intake hole, thereby effectively separating bubbles from the liquid of the solution to be tested and ensuring that the solution to be tested entering the testing section is free of bubbles.

As a technical solution of the optical concentration sensor protective casing, the outer cover is provided with two convention hole, the obstacle includes two separating plate, the liquid intake hole is disposed between the two separating plates, and the two convection holes are disposed on respective outer sides of the two separating plates.

The two convection holes may be provided, to enable the effective convection between the inner side and the outer side of the outer cover, so that the solution to be tested may quickly enter the outer cover.

The two convection holes are disposed on respective outer sides of the two separating plates, so that the separating plates may effectively space the convection holes and the liquid intake hole out, thereby more effectively separating bubbles from the liquid of the solution to be tested.

As a technical solution of the optical concentration sensor protective casing, the two separating plates are arranged in a splayed pattern.

The separating plates may be disposed on a slant, so that bubbles in the solution to be tested may float up and be discharged easily along the separating plates.

As a technical solution of the optical concentration sensor protective casing, the two separating plates include a first separating plate and a second separating plate, the liquid intake hole is located between the first separating plate and the second separating plate and at an end where a distance between the first separating plate and the second separating plate is larger, and the liquid intake hole abuts the second separating plate.

In a working state, the first separating plate may be located above the second separating plate. In the solution, the liquid intake hole abuts the second separating plate, that is, the liquid intake hole is disposed at a relatively lower position, to prevent bubbles in the solution to be tested from entering the testing section through the liquid intake hole.

As a technical solution of the optical concentration sensor protective casing, the outer cover has an open end and a closed end, and the convection holes are disposed on the periphery of the closed end of the outer cover; the bubble isolation shield has an open end and a closed end, the obstacle and the liquid intake hole are both disposed at the closed end of the bubble isolation shield, and a bubble separating cavity is formed between the closed end of the bubble isolation shield and the closed end of the outer cover.

As a technical solution of the optical concentration sensor protective casing, the bubble isolation shield is made of elastic materials.

The bubble isolation shield may be made of rubber.

The bubble isolation shield may be made of elastic materials, so that the bubble isolation shield may buffer the acting force of the solution to be tested due to icing to avoid the damages to the product caused by the acting force of the solution to be tested due to icing.

According to the invention as defined with claim <NUM>, an optical concentration testing device is provided, including the above-mentioned optical concentration sensor protective casing.

The optical concentration testing device is configured to detect the concentration of urea in the urea solution.

As a technical solution of the optical concentration testing device, the device further includes a sensor body, the sensor body is provided with a testing gap and the testing gap opens in a horizontal direction.

The sensor body is mounted within the middle fixing frame.

The testing gap is disposed on the horizontal side wall of the sensor body, so that bubbles in the solution to be tested may float up and be discharged easily along the testing gap and thus be eliminated, thereby improving the precision of the testing result.

The embodiments of the present invention have the following beneficial effects:.

The present invention will be described in detail with reference to the accompanying drawings and embodiments.

The technical solutions of the present invention are described hereinafter through embodiments in conjunction with the accompanying drawings.

As shown in <FIG>, an optical concentration sensor protective casing includes an outer cover <NUM> and a bubble isolation shield <NUM>. The bubble isolation shield <NUM> is embedded on an inner side of the outer cover <NUM>. The optical concentration sensor protective casing further includes a middle fixing frame <NUM>, an upper fixing support <NUM>, a lower fixing support <NUM> and a fixing ring <NUM>. The outer cover <NUM> and the bubble isolation shield <NUM> are mounted at one end of the middle fixing frame <NUM>, the fixing ring <NUM> is mounted at the other end of the middle fixing frame <NUM>, and the upper fixing support <NUM> and the lower fixing support <NUM> are nested on the outer sides of the middle fixing frame <NUM>. The bubble isolation shield <NUM> and the inner space of the middle fixing frame <NUM> form a testing section for a solution to be tested.

The outer cover <NUM> is provided with one or more convection holes <NUM> and the bubble isolation shield <NUM> is provided with a liquid intake hole <NUM>. An obstacle is disposed between the convection holes <NUM> and the liquid intake hole <NUM>, and a solution to be tested bypasses the obstacle from the convection holes <NUM> to the liquid intake hole <NUM>. In the present embodiment, the outer cover <NUM> is provided with two convection holes <NUM>. The obstacle includes two separating plates. The liquid intake hole <NUM> and the two separating plates are disposed on the bubble isolation shield <NUM>, the liquid intake hole <NUM> is disposed between the two separating plates, and the two convection holes <NUM> are disposed on respective outer sides of the two separating plates. In other embodiments, the separating plates may be disposed on the inner wall of the outer cover <NUM>.

The outer cover <NUM> has an open end and a closed end, and the convection holes <NUM> are disposed on the periphery of the closed end of the outer cover <NUM>. The bubble isolation shield <NUM> has an open end and a closed end, the obstacle and the liquid intake hole <NUM> are both disposed at the closed end of the bubble isolation shield <NUM>, and a bubble separating cavity is formed between the closed end of the bubble isolation shield <NUM> and the closed end of the outer cover <NUM>.

The two convection holes <NUM> may be provided to enable the effective convection between the inner side and the outer side of the outer cover <NUM>, so that the solution to be tested may quickly enter the bubble separating cavity within the outer cover <NUM>. The two separating plates are disposed, and the liquid intake hole <NUM> is disposed between the two separating plates, so that the solution to be tested needs to bypass the separating plates to reach the liquid intake hole <NUM>, thereby effectively separating bubbles from the liquid of the solution to be tested and ensuring that the solution to be tested entering the testing section is free of bubbles. The two convection holes <NUM> are disposed on respective outer sides of the two separating plates, so that the separating plates may effectively space out the convection holes <NUM> and the liquid intake hole <NUM>, thereby more effectively separating bubbles from the liquid of the solution to be tested.

In the present embodiment, the two separating plates are arranged in a splayed pattern. The separating plates may be disposed on a slant, so that bubbles in the solution to be tested may float up and be discharged easily along the separating plates. The two separating plates include a first separating plate <NUM> and a second separating plate <NUM>, the liquid intake hole <NUM> is located at an end where a distance between the first separating plate <NUM> and the second separating plate <NUM> is larger, and the liquid intake hole <NUM> abuts the second separating plate <NUM>. In the working state, the first separating plate <NUM> may be located above the second separating plate <NUM>. In the solution, the liquid intake hole <NUM> abuts the second separating plate <NUM>, that is, the liquid intake hole <NUM> is disposed at a relatively lower position, to prevent bubbles in the solution to be tested from entering the testing section through the liquid intake hole <NUM>.

The outer cover <NUM> is made of lightproof materials. The bubble isolation shield <NUM> is made of lightproof elastic materials. The bubble isolation shield <NUM> may be made of elastic materials, so that the bubble isolation shield <NUM> may buffer the acting force of the solution to be tested due to icing, so as to avoid the damages to the product caused by the acting force of the solution to be tested due to icing. In the present embodiment, the bubble isolation shield <NUM> is made of rubber.

The outer cover <NUM> is provided with a first exhaust hole <NUM> and the bubble isolation shield <NUM> is provided with a second exhaust hole <NUM>. The first exhaust hole <NUM> and the second exhaust hole <NUM> intercommunicate. The first exhaust hole <NUM> and the second exhaust hole <NUM>, which intercommunicate, may be provided for cross-ventilation between the testing section and the outside, thereby ensuring that the solution to be tested may enter the testing section. In the present embodiment, the central axis of the first exhaust hole <NUM> and the central axis of the second exhaust hole <NUM> are a same straight line.

The optical concentration sensor protective casing further includes an air hole baffle plate <NUM>. The air hole baffle plate <NUM> covers the first exhaust hole <NUM> and an interstice exists between the air hole baffle plate <NUM> and the first exhaust hole <NUM>. The air hole baffle plate <NUM> may be disposed on the outer side of the first exhaust hole <NUM>, so as to prevent the solution to be tested from directly entering the testing section through the first exhaust hole <NUM> and prevent such pollutants as dust from entering the testing section through the first exhaust hole <NUM> and affecting the precision of the testing result, thereby ensuring the reliability of the testing result. In the present embodiment, the air hole baffle plate <NUM> is secured to the upper fixing support <NUM>.

An optical concentration testing device includes the above-mentioned optical concentration sensor protective casing and a sensor body <NUM>. The sensor body <NUM> is mounted in the interior of the optical concentration sensor protective casing, the sensor body <NUM> is provided with a testing gap <NUM>, and the testing gap <NUM> opens in the horizontal direction. The testing gap <NUM> is disposed on the horizontal side wall of the sensor body <NUM>, so that bubbles in the solution to be tested may float up and be discharged easily along the testing gap <NUM> and thus be eliminated, thereby improving the precision of the testing result. In the present embodiment, the sensor body <NUM> is mounted within the middle fixing frame <NUM>. The testing gap <NUM> is V-shaped. The testing gap <NUM> of the sensor body <NUM> may open in the horizontal direction and the side walls of the testing gap <NUM> slant. In this way, if bubbles in the solution to be tested are not eliminated, the remaining bubbles will float up along the side walls of the testing gap <NUM> and be discharged from the second exhaust hole, thereby eliminating bubbles in the solution to be tested.

In a testing process, the solution to be tested may enter the bubble separating cavity through the convection holes <NUM>; the solution to be tested in the bubble separating cavity is blocked by the separating plates and is forced to change the flow direction of the solution to be tested instead of directly entering the liquid intake hole <NUM>; after the solution to be tested flows to the ends between the separating plates along the extending direction of the separating plates, the solution to be tested is no longer blocked by the separating plates and flows towards the liquid intake hole <NUM>. Because of the small density of bubbles, the doped bubbles in the solution to be tested float up and are discharged from the solution to be tested. After bubbles are eliminated, the solution to be tested enters the testing section through the liquid intake hole <NUM> and the concentration of the solution to be tested is tested by the sensor body <NUM>.

The two convection holes <NUM> may be provided, to enable the effective convection between the inner side and the outer side of the outer cover <NUM>, so that the solution to be tested may quickly enter the bubble separating cavity within the outer cover <NUM>. The two separating plates are disposed, and the liquid intake hole <NUM> is disposed between the two separating plates, so that the solution to be tested needs to bypass the separating plates to reach the liquid intake hole <NUM>, thereby effectively separating bubbles from the liquid of the solution to be tested and ensuring that the solution to be tested entering the testing section is free of bubbles. The two convection holes <NUM> are disposed on respective outer sides of the two separating plates, so that the separating plates may effectively space out the convection holes <NUM> and the liquid intake hole <NUM>, thereby more effectively separating bubbles from the liquid of the solution to be tested.

In the present embodiment, the two separating plates are spaced in parallel, the two separating plates include a first separating plate <NUM> and a second separating plate <NUM>, and the distance between the liquid intake hole <NUM> and the first separating plate <NUM> is equal to the distance between the liquid intake hole <NUM> and the second separating plate <NUM>.

The outer cover <NUM> is made of lightproof materials. The bubble isolation shield <NUM> is made of lightproof elastic materials. The bubble isolation shield <NUM> may be made of elastic materials so that the bubble isolation shield <NUM> may buffer the acting force of the solution to be tested due to icing to, so as avoid the damages to the product caused by the acting force of the solution to be tested due to icing. In the present embodiment, the bubble isolation shield <NUM> is made of rubber.

The outer cover <NUM> is provided with a first exhaust hole <NUM> and the bubble isolation shield <NUM> is provided with a second exhaust hole <NUM>. The first exhaust hole <NUM> and the second exhaust hole <NUM> are interconnected with each other. The first exhaust hole <NUM> and the second exhaust hole <NUM> interconnected with each other may be provided for cross-ventilation between the testing section and the outside, thereby ensuring that the solution to be tested may enter the testing section. In the present embodiment, the first exhaust hole <NUM> and the second exhaust hole <NUM> are staggered and the first exhaust hole <NUM> is connected to the second exhaust hole <NUM> via a pipe.

The optical concentration sensor protective casing further includes an air hole baffle plate <NUM>. The air hole baffle plate <NUM> covers the first exhaust hole <NUM> and an interstice exists between the air hole baffle plate <NUM> and the first exhaust hole <NUM>. The air hole baffle plate <NUM> may be disposed on the outer side of the first exhaust hole <NUM>, so as to prevent the solution to be tested from directly entering the testing section through the first exhaust hole <NUM> and prevent such pollutants as dust from entering the testing section through the first exhaust hole <NUM> and affecting the precision of the testing result, thereby ensuring the reliability of the testing result. In the present embodiment, the air hole baffle plate <NUM> is secured to the middle fixing frame <NUM>.

An optical concentration testing device includes the above-mentioned optical concentration sensor protective casing and a sensor body <NUM>. The sensor body <NUM> is mounted in the interior of the optical concentration sensor protective casing, the sensor body <NUM> is provided with a testing gap <NUM>, and the testing gap <NUM> opens in the horizontal direction. The testing gap <NUM> is disposed on the horizontal side wall of the sensor body <NUM> so that bubbles in the solution to be tested may float up and be discharged easily along the testing gap <NUM> and thus be eliminated, thereby improving the precision of the testing result. In the present embodiment, the sensor body <NUM> is mounted within the middle fixing frame <NUM>. The testing gap <NUM> is semi-circular. The testing gap <NUM> of the sensor body <NUM> may open in the horizontal direction and the side walls of the testing gap <NUM> slant. In this way, if bubbles in the solution to be tested are not eliminated, the remaining bubbles will float up along the side walls of the testing gap <NUM> and be discharged from the second exhaust hole, thereby eliminating bubbles in the solution to be tested.

In a testing process, the solution to be tested may enter the bubble separating cavity through the convection holes <NUM>; the solution to be tested in the bubble separating cavity is blocked by the separating plates and is forced to change the flow direction of the solution to be tested instead of directly entering the liquid intake hole <NUM>; after the solution to be tested flows to the ends between the separating plates along the extending direction of the separating plates, the solution to be tested is no longer locked by the separating plates and flows towards the liquid intake hole <NUM>. Because of the small density of bubbles, the doped bubbles in the solution to be tested float up and are discharged from the solution to be tested. After bubbles are eliminated, the solution to be tested enters the testing section through the liquid intake hole <NUM> and the concentration of the solution to be tested is tested by the sensor body <NUM>.

As shown in <FIG>, an optical concentration sensor protective casing includes an outer cover <NUM> and a bubble isolation shield <NUM>. The bubble isolation shield <NUM> is embedded on an inner side of the outer cover <NUM>. The optical concentration sensor protective casing further includes a middle fixing frame <NUM>, an upper fixing support <NUM>, a lower fixing support <NUM> and a fixing ring <NUM>. The outer cover <NUM> and the bubble isolation shield <NUM> are mounted at one end of the middle fixing frame <NUM>, the fixing ring <NUM> is mounted at the other end of the middle fixing frame <NUM>, and the upper fixing support <NUM> and the lower fixing support <NUM> are nested on the outer sides of the middle fixing frame <NUM>. The inner space of the bubble isolation shield <NUM> and the inner space of the middle fixing frame <NUM> form a testing section for a solution to be tested.

The two convection holes <NUM> may be provided, to enable the effective convection between the inner side and the outer side of the outer cover <NUM> so that the solution to be tested may quickly enter the bubble separating cavity within the outer cover <NUM>. The two separating plates are disposed, and the liquid intake hole <NUM> is disposed between the two separating plates, so that the solution to be tested needs to bypass the separating plates to reach the liquid intake hole <NUM>, thereby effectively separating bubbles from the liquid of the solution to be tested and ensuring that the solution to be tested entering the testing section is free of bubbles. The two convection holes <NUM> are disposed on respective outer sides of the two separating plates so that the separating plates may effectively space out the convection holes <NUM> and the liquid intake hole <NUM>, thereby more effectively separating bubbles from the liquid of the solution to be tested.

In the present embodiment, the two separating plates are spaced in parallel, the two separating plates include a first separating plate <NUM> and a second separating plate <NUM>, and the liquid intake hole <NUM> abuts the second separating plate <NUM>, that is, the distance between the liquid intake hole <NUM> and the first separating plate <NUM> is larger than the distance between the liquid intake hole <NUM> and the second separating plate <NUM>. In the working state, the first separating plate <NUM> may be located above the second separating plate <NUM>. In the solution, the liquid intake hole <NUM> abuts the second separating plate <NUM>, that is, the liquid intake hole <NUM> is disposed at a relatively lower position, to prevent bubbles in the solution to be tested from entering the testing section through the liquid intake hole <NUM>.

The outer cover <NUM> is made of lightproof materials. The bubble isolation shield <NUM> is made of lightproof elastic materials. The bubble isolation shield <NUM> may be made of elastic materials so that the bubble isolation shield <NUM> may buffer the acting force of the solution to be tested due to icing, so as to avoid the damages to the product caused by the acting force of the solution to be tested due to icing, In the present embodiment, the bubble isolation shield <NUM> is made of rubber.

The outer cover <NUM> is provided with a first exhaust hole <NUM> and the bubble isolation shield <NUM> is provided with a second exhaust hole <NUM>. The first exhaust hole <NUM> and the second exhaust hole 24intercommunicate. The first exhaust hole <NUM> and the second exhaust hole <NUM>, which intercommunicate, may be provided for cross-ventilation between the testing section and the outside, thereby ensuring that the solution to be tested may enter the testing section. In the present embodiment, the central axis of the first exhaust hole <NUM> and the central axis of the second exhaust hole <NUM> are a same straight line.

The optical concentration sensor protective casing further includes an air hole baffle plate <NUM>. The air hole baffle plate <NUM> covers the first exhaust hole <NUM> and an interstice exists between the air hole baffle plate <NUM> and the first exhaust hole <NUM>. The air hole baffle plate <NUM> may be disposed on the outer side of the first exhaust hole <NUM>, so as to prevent the solution to be tested from directly entering the testing section through the first exhaust hole <NUM> and prevent such pollutants as dust from entering the testing section through the first exhaust hole <NUM> and affecting the precision of the testing result, thereby ensuring the reliability of the testing result. In the present embodiment, the air hole baffle plate <NUM> is secured to the outer cover <NUM>.

An optical concentration testing device includes the above-mentioned optical concentration sensor protective casing and a sensor body <NUM>. The sensor body <NUM> is mounted in the interior of the optical concentration sensor protective casing, the sensor body <NUM> is provided with a testing gap <NUM>, and the testing gap <NUM> opens in the horizontal direction. The testing gap <NUM> is disposed on the horizontal side wall of the sensor body <NUM>, so that bubbles in the solution to be tested may float up and be discharged easily along the testing gap <NUM> and thus be eliminated, thereby improving the precision of the testing result. In the present embodiment, the sensor body <NUM> is mounted within the middle fixing frame <NUM>. The testing gap <NUM> is trapezoidal. The testing gap <NUM> of the sensor body <NUM> may open in the horizontal direction and the side walls of the testing gap <NUM> slant. In this way, if bubbles in the solution to be tested are not eliminated, the remaining bubbles will float up along the side walls of the testing gap <NUM> and be discharged from the second exhaust hole, thereby eliminating bubbles in the solution to be tested.

As shown in <FIG>, an optical concentration sensor protective casing includes an outer cover <NUM> and a bubble isolation shield <NUM>. The bubble isolation shield <NUM> is embedded on an inner side of the outer cover <NUM>. The optical concentration sensor protective casing further includes a middle fixing frame <NUM>, an upper fixing support <NUM>, a lower fixing support <NUM> and a fixing ring <NUM>. The outer cover <NUM> and the bubble isolation shield <NUM> are mounted at one end of the middle fixing frame <NUM>, the fixing ring <NUM> is mounted at the other end of the middle fixing frame <NUM>, and the upper fixing support <NUM> and the lower fixing support <NUM> are nested on the outer sides of the middle fixing frame <NUM>, The bubble isolation shield <NUM> and the inner space of the middle fixing frame <NUM> form a testing section for a solution to be tested.

In the present embodiment, the two separating plates are arranged in a splayed pattern. The separating plates may be disposed on a slant so that bubbles in the solution to be tested may float up and be discharged easily along the separating plates. The two separating plates include a first separating plate <NUM> and a second separating plate <NUM>, the liquid intake hole <NUM> is located at an end where a distance between the first separating plate <NUM> and the second separating plate <NUM> is larger, and the distance between the liquid intake hole <NUM> and the first separating plate <NUM> is equal to the distance between the liquid intake hole <NUM> and the second separating plate <NUM>.

In a testing process, the solution to be tested may enter the bubble separating cavity through the convection holes <NUM>; the solution to be tested in the bubble separating cavity is blocked by the separating plates and is forced to change the flow direction of the solution to be tested instead of directly entering the liquid intake hole <NUM>; after the solution to be tested flows to the end between the separating plates along the extending direction of the separating plates, the solution to be tested is on longer blocked by the separating plates and flows towards the liquid intake hole <NUM>. Because of the small density of bubbles, the doped bubbles in the solution to be tested float up and are discharged from the solution to be tested. After bubbles are eliminated, the solution to be tested enters the testing section through the liquid intake hole <NUM> and the concentration of the solution to be tested is tested by the sensor body <NUM>.

The terms "first" and "second" in the specification are only used for descriptive purposes and have no special meanings.

It is to be noted that the above technical solutions are merely embodiments of the present invention and, within the technical scope disclosed by the present invention, any change or substitution easily conceivable to those skilled in the art should fall within the protection scope of the present invention.

Claim 1:
An optical concentration testing device comprising an optical concentration sensor protective casing, wherein,
said optical concentration sensor protective casing comprises an outer cover (<NUM>), and a bubble isolation shield (<NUM>) embedded on an inner side of the outer cover (<NUM>);
the outer cover (<NUM>) is provided with a convection hole (<NUM>); and
the bubble isolation shield (<NUM>) is provided with a liquid intake hole (<NUM>);
said optical concentration sensor protective casing further comprises a middle fixing frame (<NUM>) and an air hole baffle plate (<NUM>),
wherein the outer cover (<NUM>) is provided with a first exhaust hole (<NUM>), the air hole baffle plate (<NUM>) covers the first exhaust hole (<NUM>), and an interstice exists between the air hole baffle plate (<NUM>) and the first exhaust hole (<NUM>),
wherein the bubble isolation shield (<NUM>) is provided with a second exhaust hole (<NUM>), the first exhaust hole (<NUM>) and the second exhaust hole (<NUM>) intercommunicate,
wherein the outer cover (<NUM>) and the bubble isolation shield (<NUM>) are mounted at one end of the middle fixing frame (<NUM>), the bubble isolation shield (<NUM>) and an inner space of the middle fixing frame (<NUM>) form a testing section for a solution to be tested,
said optical concentration testing device further comprises a sensor body (<NUM>) configured to test the concentration of the solution and mounted in the interior of the optical concentration sensor protective casing, and
characterized in that, the sensor body (<NUM>) is provided with a testing gap (<NUM>) opening in a horizontal direction and disposed on a horizontal side wall of the sensor body (<NUM>), the sensor body (<NUM>) is mounted within the middle fixing frame (<NUM>), and the testing gap (<NUM>) has slanted side walls, so that if bubbles in the solution to be tested are not eliminated and enter into the testing section, the remaining bubbles in the testing section will float up along the slanted side walls of the testing gap (<NUM>) and be discharged from the second exhaust hole (<NUM>).