CN212409942U - EGR differential pressure sensor - Google Patents

Abstract

The utility model relates to the technical field of pressure sensors, and discloses an EGR differential pressure sensor, wherein a detection unit comprises a detection core body and a drainage pipeline, wherein the detection core body comprises a sintering seat internally provided with a pressure detection element and metal pressure diaphragms arranged at two ends of the sintering seat; the drainage pipeline is connected at two ends of the detection core body and communicated with the pressure testing pipe orifice, and is used for draining the detected gas to the detection core body from the pressure testing pipe orifice, so that the particle pollutants such as carbon deposit and the like are far away from the detection core body. This EGR differential pressure sensor through add the drainage pipeline that has the direction drainage function to detecting the core, will be surveyed the gas and separate with the pressure detection component of sensor, only with the metal pressure diaphragm contact that detects the core, drainage pipeline's direction has the buffering effect to the gas of being surveyed that has great impact force, makes the long-pending charcoal particle adhere to at the drainage pipeline inner wall simultaneously, separates long-pending charcoal and detection core, avoids being corroded.

Description

EGR differential pressure sensor

Technical Field

The utility model relates to a pressure sensor technical field specifically is a EGR differential pressure sensor.

Background

An EGR differential pressure sensor is a sensor for measuring the difference between two pressures, and is generally used for measuring the pressure difference between the front and rear ends of a certain device or component, and the most typical application is the Exhaust Gas pressure difference for Exhaust Gas recirculation systems.

In the prior art, in the exhaust gas recirculation system of the vehicle, exhaust gas and carbon deposit, such as carbon monoxide CO, hydrocarbon HC, nitrogen oxide NOx, sulfide and PM (particulate matters are composed of heavy metal oxides such as soot and lead oxide, soot, oil vapor and the like), the exhaust gas temperature is high, the carbon deposit speed is high, the piezoresistive detection element is damaged by high-temperature exhaust gas and quick carbon deposit particles remained in an exhaust gas loop, meanwhile, the nitrogen oxide forms an acidic solution when meeting water vapor, and the piezoresistive detection element and a circuit of the corrosion-prone sensor are formed; therefore, it is desirable to isolate the piezoresistive detection element from the pollutants, and at the same time, the exhaust gas pressure in the exhaust gas loop is small, the use environment is severe, and a corrosion-resistant, high-temperature-resistant and accurate pressure measurement unit is needed, so as to accurately sense the pipeline pressure and protect the pressure detection unit, and thus an EGR differential pressure sensor is provided to solve the above-mentioned problems.

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved

The utility model provides a not enough to prior art, the utility model provides a EGR differential pressure sensor possesses advantages such as bearing big pressure impact and high-speed long-pending charcoal, and the EGR differential pressure sensor who has solved among the current technique is when using, and remaining high temperature waste gas and quick long-pending charcoal particle can make piezoresistive detecting element damage in the waste gas return circuit, and nitrogen oxide meets water vapor simultaneously and forms acid solution, the problem of the piezoresistive detecting element and the circuit of perishable sensor.

(II) technical scheme

For the purpose of realizing the above-mentioned big pressure impact of bearing and high-speed long-pending charcoal, the utility model provides a following technical scheme: an EGR differential pressure sensor comprises a shell and an upper cover covering the shell, wherein a detection unit is arranged in the shell, and an electrical connector electrically connected with the detection unit is arranged on the upper cover; still be equipped with two pressure test mouths of pipe in the shell for let in the gas of being surveyed to the detecting element, the detecting element is including detecting core and drainage pipeline, drainage pipeline connects at the both ends that detect the core to drainage pipeline still communicates with the pressure test mouth of pipe to be connected, drainage pipeline is used for leading to the detection gas that detects the core to the pressure test mouth of pipe drainage.

Preferably, the detection core body is vertically arranged inside the shell through a first clamping spring plate.

Preferably, the drainage pipeline comprises a drainage short pipe and a drainage long pipe, and the drainage short pipe is coaxially and hermetically connected to the lower end of the vertically arranged detection core body; the drainage long tube is connected to the upper end of the vertically arranged detection core body in a sealing mode.

Preferably, the drainage long tube is used for guiding and draining the tested gas led in from the pressure testing tube opening by one hundred eighty degrees; the drainage long tube comprises a first connecting tube, the two ends of the first connecting tube are respectively connected with a first sealing connector and a second sealing connector in a communicating manner, the first sealing connector and the second sealing connector are vertically arranged at the two ends of the first connecting tube, and openings of the first sealing connector and the second sealing connector are downward; the opening of the first sealed connector is hermetically connected with the upper end of the vertically arranged detection core body; the opening of the second sealing connector is communicated with the pressure testing pipe orifice.

Preferably, a third sealing joint is arranged in a pressure testing pipe orifice communicated with the second sealing joint in the shell, and the third sealing joint is in sealing connection with the second sealing joint.

Preferably, the first clamp spring plate is further connected with a fixing buckle, and the fixing buckle is used for reinforcing connection between the drainage long tube and the vertically arranged detection core body.

Preferably, the detection core body is horizontally arranged inside the shell through a second clamping spring plate.

Preferably, the drainage pipelines are two same drainage pipelines and are symmetrically and hermetically connected to two ends of the detection core body which is horizontally arranged.

Preferably, the drainage pipeline is used for guiding and draining the tested gas led in by the pressure testing pipe orifice by one hundred eighty degrees; the drainage pipeline comprises a second connecting pipe which is vertically arranged; the upper end of the second connecting pipe is closed, and the lower end of the second connecting pipe is opened; the opening of the second connecting pipe is coaxially connected with a third sealing connector, and the third sealing connector is communicated with the pressure testing pipe orifice; the pipe wall of the closed end of the second connecting pipe is communicated and connected with a fourth sealing joint; the second connecting pipe is horizontally arranged and is connected with two ends of the horizontally arranged detection core body in a sealing mode.

Preferably, the detection core body comprises a sintering seat with a pressure detection element arranged inside and metal pressure diaphragms arranged at two ends of the sintering seat.

(III) advantageous effects

Compared with the prior art, the utility model provides a EGR differential pressure sensor possesses following beneficial effect:

1. according to the EGR differential pressure sensor, the drainage pipeline with the guiding and drainage functions is additionally arranged on the detection core body, so that the detected gas is separated from other elements of the sensor and only contacts the detection part of the detection core body, and the corrosion is reduced; drainage tube's direction has the buffering effect to the measured gas that has great impact force, makes the long-pending charcoal particle adhere to at the drainage tube inner wall simultaneously, separates long-pending charcoal and detection core, avoids being corroded, in addition, because drainage tube's direction makes nitrogen oxide meet water vapour and form acid solution and be difficult to and detect the core contact to avoid being corroded, bear the influence of high-speed long-pending charcoal, improve life and measuring accuracy, increase the durability.

2. The EGR differential pressure sensor has the advantages that the metal pressure diaphragm arranged on the detection core body is in contact with the detected gas to avoid corrosion, and the EGR differential pressure sensor is impact-resistant.

3. According to the EGR differential pressure sensor, the connection mode of the detection core body, the shell and the flexible plate which are horizontally or vertically arranged is simple, and the production and the processing are convenient.

Drawings

Fig. 1 is a schematic overall structure diagram of a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of a detection unit and a housing in a first embodiment of the present invention.

Fig. 3 is a schematic structural diagram of the housing in the first embodiment of the present invention;

FIG. 4 is a schematic structural view of a detecting unit according to a first embodiment of the present invention

Fig. 5 is a schematic structural view of a detection core and a long drainage tube in the first embodiment of the present invention;

FIG. 6 is a schematic view of the structure of the long drainage tube in the first embodiment of the present invention

Fig. 7 is a schematic overall structure diagram of a second embodiment of the present invention;

FIG. 8 is a schematic structural view of a detecting unit and a housing according to a second embodiment of the present invention

Fig. 9 is a schematic structural diagram of a detecting unit in a second embodiment of the present invention;

FIG. 10 is a schematic structural view of a detecting unit according to a second embodiment of the present invention

In the figure: the device comprises a shell 1, an upper cover 2, an electrical connector 3, a first detection unit 4, a first clamp spring plate 41, a detection core body in a 42 vertical state, a 43 fixing buckle, a long drainage pipe 44, a first connecting pipe 441, a first sealed connecting head 442, a second sealed connecting head 443, a first flexible plate 45, a short drainage pipe 46, a metal pressure membrane 47, a second detection unit 5, a second clamp spring plate 51, a drainage pipeline 52, a second connecting pipe 521, a third sealed connecting head 522, a fourth sealed connecting head 523, a detection core body in a 53 horizontal state and a second flexible plate 54.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

An EGR differential pressure sensor comprises a shell 1 and an upper cover 2 covering the shell, wherein a detection unit is arranged in the shell 1, an electrical connector 3 electrically connected with the detection unit is arranged on the upper cover 2, two pressure test pipe orifices used for leading gas to be detected into the detection unit are arranged in the shell 1, the detection unit comprises a detection core body and a drainage pipeline, the detection core body comprises a sintering seat internally provided with a pressure detection element and metal pressure diaphragms arranged at two ends of the sintering seat, a pressure conduction medium is filled and sealed in the sintering seat, wherein the pressure detection element can be a piezoresistive detection element, the pressure transmission medium can be silicon oil, the sintering seat can be cylindrical, the metal pressure diaphragm and the sintering seat are sealed and fixedly connected, the pressure detection medium is sealed and stored in the sintering seat, when the pressure of the gas to be detected acts on the metal pressure diaphragm, the pressure is transmitted to the pressure detection element through the pressure transmission medium for detection; the drainage pipelines are connected to two ends of the detection core body and communicated with the pressure testing pipe orifice and are used for draining the detected gas from the pressure testing pipe orifice to the detection core body for detecting pressure and enabling carbon deposit generated at high speed to be far away from the detection core body so as to avoid corrosion; the specific structure of the detection core body and the drainage pipeline refers to the following two embodiments;

example one

In the first detection unit 4 shown in fig. 1-6, the drainage pipeline structure corresponding to the core body in the vertical arrangement state is detected;

the metal pressure membrane 47 on the vertical detection core body 42 protects the vertical detection core body, the vertical detection core body 42 is fixedly arranged on the shell 1 through the first clamp spring plate 41, and the first clamp spring plate 41 is matched with the shell 1; the drainage pipeline consists of a drainage short pipe 46 and a drainage long pipe 44, the drainage short pipe 46 is coaxially and hermetically connected to the lower end of the detection core body 42 in a vertical state and is communicated with one of the pressure testing pipe orifices 101 in the shell 1; the drainage long tube 44 is hermetically connected to the upper end of the vertical detection core 42 and is communicated with another pressure testing tube opening 102 in the shell 1, so that the gas to be detected is introduced into the vertical detection core 42; the first clamp spring plate 41 is also connected with a fixing buckle 43, and the fixing buckle 43 is used for reinforcing the connection between the drainage long tube 44 and the vertically arranged detection core body 42; the short drainage tube 46 is cylindrical, the long drainage tube 44 is cylindrical,

the drainage long tube 44 is used for guiding and draining one hundred eighty degrees of the gas to be tested, which is guided by the pressure testing tube opening 102, and the specific structure is that the drainage long tube 44 comprises a first connecting tube 441 which is horizontally arranged, two ends of the first connecting tube 441 are respectively connected with a first sealing connector 442 and a second sealing connector 443 in a communicating manner, the first sealing connector 442 and the second sealing connector 443 are vertically arranged at two ends of the first connecting tube 441, and the openings of the first sealing connector 442 and the second sealing connector 443 face downwards; the opening of the first sealed connector 442 is connected with the upper end of the vertically arranged detection core body 42; the opening of the second sealing connector 443 is communicated with the corresponding pressure testing pipe orifice 102; a third sealing joint 103 is arranged in the pressure testing pipe orifice 102 corresponding to the second sealing joint 443 in the casing 1, and the third sealing joint 103 is in sealing connection with the second sealing joint 443; therefore, the tested gas at the position of the pressure testing pipe opening 102 is guided in a drainage way, and the pipeline structure buffers the entering gas, so that the high-speed carbon deposit is attached to the drainage long pipe 44 and is far away from the vertically arranged detection core body 42; in addition, the nitrogen oxide forms an acidic solution with water vapor and is difficult to turn and flows down along the second sealing connector 443, so that the nitrogen oxide is difficult to contact the metal pressure membrane 47, and the nitrogen oxide is prevented from being corroded; in addition, the gas to be detected entering from the pressure testing pipe orifice 101 passes through the first connecting pipe 441 to partially protect the metal pressure diaphragm 47, and meanwhile, carbon deposit is attached, so that the two ends of the vertically arranged detection core body 42 are protected; corrosion-resistant gaskets and sealing rings are additionally arranged at the sealing joints;

in addition, the metal pressure diaphragm 47 can bear higher impact force and resist corrosion, and protects the sintering seat from being corroded; be equipped with on the first jump ring board 41 with the perpendicular first flexographic plate 45 that sets up detect core 42 electrical connection, be provided with circuit and circuit element on the first flexographic plate 45, first flexographic plate 45 still with electrical joint 3 electrical connection for the signal that the transmission detected, and avoid with the gas contact that is surveyed, finally make the detecting element can bear the influence of the high-speed long-pending charcoal in the waste gas return circuit and the influence that the aqueous vapor of nitrogen oxide formed the acid solution and corrodes, improve its life and increase and detect the precision, strengthen its durability.

Example two

As shown in fig. 7-10, the detection core in the second detection unit 5 is a drainage pipe structure corresponding to the detection core in a horizontal arrangement state; .

The horizontal detection core body 53 is internally provided with a metal pressure diaphragm 47 for protecting two ends of the horizontal detection core body, the horizontal detection core body 53 is arranged in the shell 1 through a second clamp spring plate 51, the second clamp spring plate 51 is matched with a sintering seat of the horizontal detection core body 53, and the second clamp spring plate 51 is provided with a mounting hole matched with the sintering seat; the drainage pipelines are symmetrically and hermetically connected to two ends of the horizontally arranged detection core body 53 and are communicated with the pressure testing pipe orifice 102 and the pressure testing pipe orifice 101;

the symmetrical drainage pipeline 52 is used for guiding and draining the tested gas introduced by the pressure testing pipe orifice 102 and the pressure testing pipe orifice 101 by one hundred eighty degrees; the symmetrical drainage pipeline comprises a second connecting pipe 521, the upper end of the second connecting pipe 521 is closed, the lower end of the second connecting pipe 521 is open, a third sealing connector 522 is coaxially connected to the opening of the second connecting pipe 521 and is communicated and connected with the pressure testing pipe orifice 102 or the pressure testing pipe orifice 101, and a fourth sealing connector 523 is communicated and connected to the pipe wall of the closed end of the second connecting pipe 521; the fourth sealing joint 523 is horizontally disposed and is hermetically connected to the horizontal detection core 53; the detection core body 53 that the level set up has second flexographic plate 54 of electric connection, is provided with circuit and circuit component on the second flexographic plate 54 and still connects with electrical joint 3 electric connection, and all add corrosion-resistant packing ring and sealing washer above the sealing connection department to cushion the waste gas in the vehicle exhaust gas recirculation system, make the carbon deposit keep away from the detection core body 53 that the level set up, make it increase life and increase and detect the precision.

When in use:

(1) the gas under test enters into and detects the drainage tube that the core both ends communicate respectively from pressure test mouth of pipe 101 and pressure test mouth of pipe 102 to detect the both ends of core and carry out the detection pressure, when the gas under test circulates in drainage tube, the long-pending charcoal that produces at high speed in the gas under test can be cushioned attached to on drainage tube's the pipe wall, thereby separates long-pending charcoal and detection core, avoids its influence to detect the effect.

(2) The guide structure of the drainage pipeline enables nitric oxide in the detected gas to form an acid solution when meeting water vapor, so that the detection core body is prevented from being corroded, and the detection core body of the metal pressure diaphragm is protected, so that the detection core body has corrosion resistance and impact resistance.

In conclusion, the problem that when the EGR differential pressure sensor in the prior art is used, the piezoresistive detection element can be damaged by high-temperature waste gas and quick carbon deposition particles remained in a waste gas loop, and meanwhile, nitrogen oxides form an acidic solution when meeting water vapor, so that the piezoresistive detection element and a circuit of the sensor are prone to corrosion is solved.

The utility model has the advantages that: a drainage pipeline with a guiding drainage function is additionally arranged on the detection core body, so that the detected gas is separated from other elements of the sensor and only contacts with the detection part of the detection core body, and the corrosion is reduced; the guide of the drainage pipeline has a buffering effect on the detected gas with larger impact force, and simultaneously, carbon deposit particles are attached to the inner wall of the drainage pipeline to separate the carbon deposit from the detection core body and avoid corrosion; the metal pressure diaphragm arranged on the detection core body is in contact with the detected gas to avoid corrosion and resist impact; the detection core body which is horizontally or vertically arranged is simple in connection with the shell and the flexible plate, and production and processing are facilitated.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (10)

1. An EGR differential pressure sensor comprises a shell (1) and an upper cover (2) covered on the shell, wherein a detection unit is arranged in the shell (1), and an electrical connector (3) electrically connected with the detection unit is arranged on the upper cover (2); still be equipped with two pressure test mouths of pipe in shell (1) for let in to the detecting element by the gas, its characterized in that: the detecting unit is including detecting core and drainage pipeline, drainage pipeline connects at the both ends that detect the core to drainage pipeline still communicates with the pressure test mouth of pipe to be connected, drainage pipeline is used for leading to the detection gas that detects the core to the pressure test mouth of pipe drainage.

2. An EGR differential pressure sensor according to claim 1, wherein: the detection core body is vertically arranged inside the shell (1) through a first clamp spring plate (41).

3. An EGR differential pressure sensor according to claim 2, wherein: the drainage pipeline comprises a drainage short pipe (46) and a drainage long pipe (44), and the drainage short pipe (46) is coaxially and hermetically connected to the lower end of the vertically arranged detection core body; the drainage long tube (44) is connected to the upper end of the vertically arranged detection core body in a sealing manner.

4. An EGR differential pressure sensor according to claim 3, wherein: the drainage long pipe (44) is used for guiding and draining the tested gas led in by the pressure testing pipe orifice by one hundred eighty degrees; the drainage long tube (44) comprises a first connecting tube (441), two ends of the first connecting tube (441) are respectively connected with a first sealing connector (442) and a second sealing connector (443) in a communicating manner, and the first sealing connector (442) and the second sealing connector (443) are vertically arranged at two ends of the first connecting tube (441) and have downward openings; the opening of the first sealing connector (442) is in sealing connection with the upper end of the vertically arranged detection core body; the opening of the second sealing connector (443) is communicated with the pressure testing pipe orifice.

5. An EGR differential pressure sensor, according to claim 4, wherein: and a third sealing joint (103) is arranged in a pressure testing pipe orifice communicated with the second sealing joint (443) in the shell (1), and the third sealing joint (103) is in sealing connection with the second sealing joint (443).

6. An EGR differential pressure sensor according to claim 2, wherein: the first clamp spring plate (41) is further connected with a fixing buckle (43), and the fixing buckle (43) is used for reinforcing connection between the drainage long tube (44) and the vertically arranged detection core body.

7. An EGR differential pressure sensor according to claim 1, wherein: the detection core body is horizontally arranged inside the shell (1) through a second clamp spring plate (51).

8. An EGR differential pressure sensor according to claim 7, wherein: the drainage pipeline is two identical drainage pipelines and is symmetrically and hermetically connected to two ends of the detection core body which is horizontally arranged.

9. An EGR differential pressure sensor according to claim 8, wherein: the drainage pipeline is used for guiding and draining the tested gas led in by the pressure testing pipe orifice by one hundred eighty degrees; the drainage pipeline comprises a second connecting pipe (521) which is vertically arranged; the upper end of the second connecting pipe (521) is closed, and the lower end of the second connecting pipe is opened; the opening of the second connecting pipe (521) is coaxially connected with a third sealing connector (522), and the third sealing connector (522) is communicated with the pressure testing pipe orifice; the pipe wall of the closed end of the second connecting pipe (521) is communicated and connected with a fourth sealing joint (523); the second connecting pipe (521) is horizontally arranged and is connected with two ends of the horizontally arranged detection core body in a sealing mode.

10. An EGR differential pressure sensor according to claim 1, wherein: the detection core body comprises a sintering seat and metal pressure diaphragms, wherein a pressure detection element is arranged in the sintering seat, and the metal pressure diaphragms are arranged at two ends of the sintering seat.

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