CN112546368B - Differential pressure type flow sensor and breathing machine - Google Patents
Differential pressure type flow sensor and breathing machine Download PDFInfo
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- CN112546368B CN112546368B CN202011369906.2A CN202011369906A CN112546368B CN 112546368 B CN112546368 B CN 112546368B CN 202011369906 A CN202011369906 A CN 202011369906A CN 112546368 B CN112546368 B CN 112546368B
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0003—Accessories therefor, e.g. sensors, vibrators, negative pressure
- A61M2016/003—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter
- A61M2016/0033—Accessories therefor, e.g. sensors, vibrators, negative pressure with a flowmeter electrical
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- Health & Medical Sciences (AREA)
- Emergency Medicine (AREA)
- Pulmonology (AREA)
- Engineering & Computer Science (AREA)
- Anesthesiology (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Hematology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Measuring Volume Flow (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
The invention relates to a differential pressure type flow sensor, which comprises a main body, wherein the main body is provided with a flow channel for circulating airflow, the flow channel comprises an inflow section, an outflow section and a throttling section for communicating the inflow section and the outflow section, the inner wall of the throttling section extends towards the axis of the throttling section to form a plurality of long rib plates and a plurality of short rib plates, the long rib plates are arranged at intervals around the axis of the throttling section, the short rib plates are arranged at intervals around the axis of the throttling section, and the long rib plates and the short rib plates are arranged at intervals around the axis of the throttling section; on any cross section perpendicular to the axis of the throttling section, the distance between the long ribbed plate and the axis of the throttling section is larger than the distance between the short ribbed plate and the axis of the throttling section. And then the atmospheric pressure value under the low flow can be measured to long floor, and short floor is because the distance from the throttle section axis is great, consequently can guarantee the unobstructed of air current, can not take place to block up to effectual contradiction between differential resolution ratio and the differential flow sensor air resistance under the low flow of having solved, make differential flow sensor's performance better.
Description
Technical Field
The invention relates to the technical field of differential pressure type sensors, in particular to a differential pressure type flow sensor and a breathing machine.
Background
Due to the characteristics of the differential pressure type flow sensor, the flow pressure difference curve is a concave parabola, the pressure difference rapidly increases along with the increase of the flow, and the whole breathing pipeline has a certain resistance limit value, so that a contradiction exists, namely the contradiction between the low-flow lower pressure difference resolution and the differential pressure type flow sensor air resistance, namely when the measurement precision in low flow can be met, the unsmooth air flow is easily caused, and when the air flow is smooth, the measurement precision in low flow cannot be realized.
Disclosure of Invention
The invention aims to provide a differential pressure type flow sensor and a breathing machine, which can accurately measure flow parameters under low flow.
According to an aspect of the present invention, there is provided a differential pressure type flow sensor, the differential pressure type flow sensor includes a main body having a flow passage for flowing air, the flow passage includes an inflow section, an outflow section and a throttle section communicating the inflow section and the outflow section, an inner wall of the throttle section extends towards an axis of the throttle section to form a plurality of long ribs and a plurality of short ribs, the plurality of long ribs are disposed around the axis of the throttle section at intervals, the plurality of short ribs are disposed around the axis of the throttle section at intervals, and the long ribs and the short ribs are disposed around the axis of the throttle section at intervals;
on any cross section perpendicular to the axis of the throttling section, the distance between the long ribbed plate and the axis of the throttling section is larger than the distance between the short ribbed plate and the axis of the throttling section.
As an embodiment of the present invention, the long ribs and the short ribs are arranged at regular intervals around the throttle section axis.
As an embodiment of the present invention, in any direction along the axial direction of the throttle section, the distance from the long rib to the axis of the throttle section gradually decreases and then gradually increases.
As an embodiment of the present invention, in any direction along the axial direction of the throttle section, the distance from the short rib to the axis of the throttle section gradually decreases and then gradually increases.
As an embodiment of the present invention, in any cross section perpendicular to the choke axis, a difference between a distance between the long rib and the choke axis and a distance between the short rib and the choke axis is equal.
As an embodiment of the present invention, the sampling device further comprises a first sampling tube and a second sampling tube, the first sampling tube has a first sampling passage, the second sampling tube has a second sampling passage, the first sampling passage is communicated with the inflow section, and the second sampling passage is communicated with the outflow section.
As an embodiment of the invention, the first sampling pipe is provided at an inlet end of the throttle section and the second sampling pipe is provided at an outlet end of the throttle section.
As an embodiment of the present invention, the throttling section is a laval flow passage.
As an embodiment of the invention, the wall thickness of each position of the throttling section is equal, the outer wall of the throttling section extends towards the direction far away from the axis of the throttling section to form a plurality of reinforcing ribs, and the plurality of reinforcing ribs are arranged at intervals around the axis of the throttling section.
According to another aspect of the present invention there is provided a ventilator comprising a differential pressure flow sensor as described in any of the embodiments above.
The embodiment of the invention has the following beneficial effects:
the differential pressure type flow sensor in the embodiment forms a plurality of long ribbed plates and a plurality of short ribbed plates by extending the inner wall of the throttling section towards the axis of the throttling section, the long ribbed plates and the short ribbed plates are arranged at intervals around the axis of the throttling section, and the long ribbed plates and the short ribbed plates have certain interference resistance on airflow, so that the air pressure value of the airflow can be measured. And then the long rib can measure the atmospheric pressure value under the low flow, and short rib is because the distance from throttle section axis is great, consequently can guarantee unobstructed of air current, can not take place to block up to effectual contradiction between differential resolution and the differential flow sensor air-resistor under the low flow of having solved, the performance that makes the differential flow sensor in this embodiment is better.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic diagram of a differential pressure flow sensor according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view of the differential pressure flow sensor of FIG. 1 in one direction;
FIG. 3 is a schematic view of the differential pressure flow sensor of FIG. 1 from one perspective;
wherein: 100. a main body; 101. a flow channel; 102. an inflow section; 103. an outflow section; 104. a throttling section; 210. a long rib plate; 220. short rib plates; 300. reinforcing ribs; 410. a first sampling tube; 411. a first sampling channel; 420. a second sampling tube; 421. a second sampling channel.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Referring to fig. 1 to 3, an embodiment of the present invention provides a differential pressure flow sensor, which includes a main body 100, the main body 100 has a flow channel 101 for flowing gas, the flow channel 101 is divided into at least three sections, which are an inflow section 102, an outflow section 103, and a throttling section 104 for communicating the inflow section 102 and the outflow section 103, respectively, the inflow section 102 is used for inputting a gas flow, the outflow section 103 is used for outputting a gas flow, and a desired parameter can be measured by taking pressure values at an inlet end and an outlet end of the throttling section 104, respectively.
Preferably, the flow channel 101 has a shape that is centrosymmetric with respect to the axis thereof, thereby ensuring stability of the flow rate flowing through the flow channel 101 to improve measurement accuracy.
Preferably, the restriction 104 is a laval flow passage 101. The specific structure of the laval flow passage 101 in this embodiment is: along any axial direction of the throttling section 104, the flow cross-sectional area of the throttling section 104 is gradually reduced and then gradually increased, and the throttling section 104 is set to be in the Laval flow channel 101 form, so that when airflow passes through the throttling section 104, the flow cross-sectional areas at all positions are different in size, and further the resistance to the airflow is different, and therefore the linearity of the differential pressure type flow sensor can be improved, the differential pressure resolution under low flow is improved, and the measurement accuracy of the differential pressure type flow sensor in the embodiment is higher.
Specifically, the inner wall of the throttle section 104 extends towards the axis of the throttle section 104 to form a plurality of long ribs 210 and a plurality of short ribs 220, the plurality of long ribs 210 are arranged around the axis of the throttle section 104 at intervals, the plurality of short ribs 220 are arranged around the axis of the throttle section 104 at intervals, and the long ribs 210 and the short ribs 220 are arranged around the axis of the throttle section 104 at intervals; in any cross section perpendicular to the axis of the throttle section 104, the distance between the long rib 210 and the axis of the throttle section 104 is greater than the distance between the short rib 220 and the axis of the throttle section 104. And then long rib 210 can measure the atmospheric pressure value under the low flow, and short rib 220 is because the distance from throttle section 104 axis is great, therefore can guarantee the unobstructed of air current, can not take place to block up to effectual the contradiction between differential resolution and the differential flow sensor air resistance under the low flow of having solved, make the performance of the differential flow sensor in this embodiment better.
Referring to fig. 3, in one embodiment, the long ribs 210 and the short ribs 220 are uniformly spaced around the axis of the throttle section 104. Through surrounding the even interval setting of throttle section 104 axis with long rib 210 and short rib 220, can make the stability of the air current of circulation better, the indirect measurement accuracy that can improve the differential pressure type flow sensor in this embodiment.
Referring to fig. 2, in one embodiment, the distance from the long rib 210 to the axis of the throttle section 104 gradually decreases and then gradually increases along any axial direction of the throttle section 104. In this embodiment, when the airflow passes through the throttle section 104, the resistance of each position of the long rib plate 210 to the airflow is different, so that the resolution of the differential pressure type flow sensor can be further improved.
It is also preferred that the short rib 220 is gradually smaller and then gradually larger toward the axis of the throttle section 104 in either axial direction of the throttle section 104. In this embodiment, when the airflow passes through the throttle section 104, the resistances of the positions of the short ribs 220 to the airflow are different, so that the resolution of the differential pressure type flow sensor can be further improved.
It should be noted that, in the differential pressure type flow sensor of the present embodiment, the distance from the long rib 210 to the axis of the throttle section 104 may gradually decrease and then gradually increase, the distance from the short rib 220 to the axis of the throttle section 104 may gradually decrease and then gradually increase, or the distance from both the long rib 210 and the short rib 220 to the axis of the throttle section 104 may gradually decrease and then gradually increase.
Further, in any cross section perpendicular to the axis of the throttle section 104, the distance between the long rib 210 and the axis of the throttle section 104 is equal to the difference between the distance between the short rib 220 and the axis of the throttle section 104, thereby further improving the stability of the airflow passing through the throttle section 104.
It should be noted that the distance between the long rib 210 and the axis of the throttle section 104 may be 0, and it is preferable that the distance between the long rib 210 and the axis of the throttle section 104 is not 0, for example, the distance between the long rib 210 and the axis of the throttle section 104 is 5-10mm.
In some embodiments, the positions of the long ribs 210 are equidistant from the axis of the throttle section 104, and likewise, the positions of the short ribs 220 are equidistant from the axis of the throttle section 104.
In some embodiments, the thickness of the long ribs 210 is 1-10mm, and preferably, the thickness of the long ribs 210 is 1-5mm. When the long rib 210 is within the thickness range, the effect of the long rib on the airflow passing through the throttle section 104 is most significant, and the resolution of the differential pressure flow sensor in this embodiment is kept high.
Also, the thickness of the short rib 220 is 1 to 10mm, and preferably, the thickness of the short rib 220 is 1 to 5mm. When the short rib 220 is within the thickness range, it has the most significant effect on the airflow passing through the throttle section 104, so that the resolution of the differential pressure flow sensor in this embodiment is kept high.
Based on the purpose of improving the resolution of the differential pressure type flow sensor in this embodiment, the wall thicknesses of the positions of the throttling section 104 are equal, because the throttling section 104 is of a structure of the laval flow passage 101, and further, the outer wall of the throttling section 104 is concave towards the axis of the throttling section 104, in order to ensure the strength of the throttling section 104, the outer wall of the throttling section 104 extends towards the direction away from the axis to form a plurality of reinforcing ribs 300, the plurality of reinforcing ribs 300 are arranged around the axis of the throttling section 104 at intervals, and the strength of the throttling section 104 can be obviously improved through the plurality of reinforcing ribs 300, so that the service life of the throttling section 104 is prolonged.
Preferably, the long rib 210, the short rib 220 and the main body 100 are integrally formed, thereby improving the structural stability thereof.
Further, the reinforcing rib 300 is integrally formed with the main body 100, thereby improving the structural stability thereof.
Referring to fig. 1, in an embodiment, the differential pressure type flow sensor further includes a first sampling tube 410 and a second sampling tube 420, the first sampling tube 410 has a first sampling channel 411, the second sampling tube 420 has a second sampling channel 421, the first sampling channel 411 is communicated with the inflow section 102, and the second sampling channel 421 is communicated with the outflow section 103. The inlet end of the throttle section 104 can be measured by a first sampling channel 411 and the outlet end of the throttle section 104 can be measured by a second sampling channel 421.
Preferably, the distance between the first sampling tube 410 and the throttle section 104 is equal to the distance between the second sampling tube 420 and the throttle section 104. In this embodiment, the first sampling tube 410 and the second sampling tube 420 are symmetric with respect to the throttle section 104, so that a user can perform two-way measurement, thereby increasing the convenience of installing the differential pressure type flow sensor in this embodiment.
Further, a first sampling tube 410 is disposed at the inlet end of the throttle section 104 and a second sampling tube 420 is disposed at the outlet end of the throttle section 104. The samples are respectively collected at the inlet end and the outlet end of the throttle section 104, and since the data of the position is relatively strong in representativeness, the first sampling pipe 410 is arranged at the inlet end of the throttle section 104, and the second sampling pipe 420 is arranged at the outlet end of the throttle section 104, so that the measurement accuracy of the differential pressure type flow sensor in the embodiment can be further improved.
An embodiment of the present invention further provides a ventilator, in which the ventilator in this embodiment includes the differential pressure type flow sensor in any embodiment, and because the linearity of the differential pressure type flow sensor in the above embodiment is better, the contradiction between the differential pressure resolution at low flow and the air resistance of the differential pressure type flow sensor is effectively solved, and the measurement accuracy at low flow is improved. Therefore, the monitoring performance of the respirator provided with the differential pressure type flow sensor is better, the use is safer, and the performance is better.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent should be subject to the appended claims.
Claims (9)
1. A differential pressure type flow sensor is characterized by comprising a main body, wherein the main body is provided with a flow channel for circulating airflow, the flow channel comprises an inflow section, an outflow section and a throttling section communicated with the inflow section and the outflow section, the inner wall of the throttling section extends towards the axis of the throttling section to form a plurality of long rib plates and a plurality of short rib plates, the long rib plates are arranged around the axis of the throttling section at intervals, the short rib plates are arranged around the axis of the throttling section at intervals, and the long rib plates and the short rib plates are arranged around the axis of the throttling section at intervals;
on any cross section perpendicular to the axis of the throttling section, the distance between the long rib plate and the axis of the throttling section is smaller than the distance between the short rib plate and the axis of the throttling section, along any direction of the axial direction of the throttling section, the distance from the long rib plate to the axis of the throttling section is gradually reduced and then gradually increased, and the distance from any position of the long rib plate to the axis of the throttling section is not zero.
2. A differential flow sensor as defined in claim 1 wherein said long ribs are evenly spaced from said short ribs about said choke section axis.
3. The differential pressure flow sensor of claim 1, wherein the short ribs progressively decrease in distance toward the axis of the flow restriction section and then progressively increase in distance in either axial direction of the flow restriction section.
4. A differential flow sensor as defined in claim 3 wherein the distance between the long rib and the choke section axis is equal to the difference between the distance between the short rib and the choke section axis on any cross-section perpendicular to the choke section axis.
5. The differential pressure flow sensor of claim 1, further comprising a first sampling tube having a first sampling passage and a second sampling tube having a second sampling passage, the first sampling passage in communication with the inflow section and the second sampling passage in communication with the outflow section.
6. The differential pressure flow sensor of claim 5, wherein the first sampling tube is disposed at an inlet end of the throttling section and the second sampling tube is disposed at an outlet end of the throttling section.
7. The differential flow sensor of claim 1, wherein the flow restriction is a Laval flow path.
8. The differential pressure flow sensor of claim 7, wherein the wall thickness of the throttling section is substantially equal at each location, and the outer wall of the throttling section extends away from the axis to form a plurality of ribs spaced around the axis of the throttling section.
9. A ventilator comprising a differential pressure flow sensor as claimed in any one of claims 1 to 8.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011369906.2A CN112546368B (en) | 2020-11-30 | 2020-11-30 | Differential pressure type flow sensor and breathing machine |
| PCT/CN2021/096580 WO2022110715A1 (en) | 2020-11-30 | 2021-05-28 | Differential pressure type flow sensor and ventilator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011369906.2A CN112546368B (en) | 2020-11-30 | 2020-11-30 | Differential pressure type flow sensor and breathing machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112546368A CN112546368A (en) | 2021-03-26 |
| CN112546368B true CN112546368B (en) | 2022-12-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011369906.2A Active CN112546368B (en) | 2020-11-30 | 2020-11-30 | Differential pressure type flow sensor and breathing machine |
Country Status (2)
| Country | Link |
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| CN (1) | CN112546368B (en) |
| WO (1) | WO2022110715A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112546368B (en) * | 2020-11-30 | 2022-12-23 | 深圳市科曼医疗设备有限公司 | Differential pressure type flow sensor and breathing machine |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4164144A (en) * | 1977-10-26 | 1979-08-14 | Eaton Corporation | Fluid flowmeter |
| JPH08285645A (en) * | 1995-04-13 | 1996-11-01 | Mitsubishi Heavy Ind Ltd | Double venturi type current meter |
| EP2072971A1 (en) * | 2007-12-17 | 2009-06-24 | Services Pétroliers Schlumberger | Variable throat venturi flow meter |
| CN101311683A (en) * | 2007-12-29 | 2008-11-26 | 北京谊安医疗***股份有限公司 | Breathing machine and its low differential pressure type flow quantity detection mechanism |
| EP3110485B1 (en) * | 2014-02-28 | 2022-06-01 | Breas Medical AB | Flow sensor for ventilator |
| CN204864416U (en) * | 2015-05-08 | 2015-12-16 | 濡新（北京）科技发展有限公司 | Throttling arrangement |
| US9597476B1 (en) * | 2015-06-09 | 2017-03-21 | Event Medical Ltd. | Flow sensor and method |
| CN107817026B (en) * | 2017-11-29 | 2023-10-10 | 吉林大学 | High-resolution differential pressure type flow sensor based on synchronous resonance and detection method |
| CN208059950U (en) * | 2018-02-23 | 2018-11-06 | 南京亿准纳自动化控制技术有限公司 | Orifice union, rectification and flow measurement device |
| CN108332807B (en) * | 2018-02-23 | 2021-03-02 | 南京亿准纳自动化控制技术有限公司 | Throttling assembly, rectification and flow measuring device |
| CN111426354A (en) * | 2020-04-15 | 2020-07-17 | 江苏鑫亚达仪表制造有限公司 | Flow measuring mechanism and measuring device |
| CN111351532B (en) * | 2020-04-29 | 2022-03-18 | 南京润楠医疗电子研究院有限公司 | Bidirectional double-pressure-difference type respiratory flow detection sensing device and method |
| CN112546368B (en) * | 2020-11-30 | 2022-12-23 | 深圳市科曼医疗设备有限公司 | Differential pressure type flow sensor and breathing machine |
-
2020
- 2020-11-30 CN CN202011369906.2A patent/CN112546368B/en active Active
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2021
- 2021-05-28 WO PCT/CN2021/096580 patent/WO2022110715A1/en active Application Filing
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| Publication number | Publication date |
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| WO2022110715A1 (en) | 2022-06-02 |
| CN112546368A (en) | 2021-03-26 |
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