Flow sensor and medical device
By designing a diaphragm and housing structure in the flow sensor, and using an extension and a first protrusion to guide the condensate, the influence of condensate on the monitoring values was resolved, the accuracy of tidal volume control was improved, and the patient's life safety was ensured.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- MEDCAPTAIN MEDICAL TECH
- Filing Date
- 2025-05-21
- Publication Date
- 2026-05-26
AI Technical Summary
When existing flow sensors are in use, the pressure sampling points in the airflow channel are easily affected by condensation, resulting in large deviations in the monitored values, affecting the control of tidal volume, and thus threatening the patient's life safety.
A flow sensor was designed, which adopts a diaphragm and housing structure, and is equipped with an extension and a first protrusion to guide condensate water to avoid condensate water clogging the sampling hole. The condensate water is discharged through a drainage channel to ensure the unobstructed flow of the sampling hole and the accuracy of the monitored values.
This effectively prevents condensation from affecting the monitoring values, improves the accuracy of tidal volume control, and ensures patient safety.
Smart Images
Figure CN224269882U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of sensor technology, and more particularly to a flow sensor and a medical device. Background Technology
[0002] Flow sensors are crucial components in anesthesia machines and ventilators. They monitor the patient's inspiratory and expiratory flow rates and feed the data back to the control system of the anesthesia machine or ventilator. This allows the system to control parameters such as the patient's respiratory flow and tidal volume, thereby ensuring the patient's safety.
[0003] However, when using current flow sensors, the pressure sampling points in the airflow channel are easily affected by condensation, which can lead to large deviations in the monitored values and affect the control of tidal volume. If the tidal volume does not match the set value, it can endanger the patient's life. Utility Model Content
[0004] The purpose of this application is to provide a flow sensor and medical device in which the pressure sampling point is not affected by condensation, which can prevent the monitoring value from deviating, increase the control accuracy of tidal volume, match the tidal volume with the set value, and thus protect the patient's life safety.
[0005] The first aspect of this application provides a flow sensor, including: a diaphragm and two housings connected to each other.
[0006] Each housing includes a free end and a connecting end disposed opposite to each other. The housing has an airflow channel and a sampling port. The airflow channel passes through both the free end and the connecting end. An extension protrudes from the top of the inner wall of the housing, extending towards the center of the airflow channel. The sampling port passes through the extension and the housing, and is connected to the airflow channel. A first protrusion protrudes from the side of the extension away from the inner wall of the housing. The first protrusion is located around the sampling port, and its position is lower than that of the sampling port.
[0007] The diaphragm has a slit that extends through the diaphragm along its thickness.
[0008] A diaphragm is placed between two housings, with the two sides of the diaphragm respectively attached to the connecting ends of the two housings along its thickness direction, and the gap connecting the airflow channels of the two housings.
[0009] In some embodiments, the length of the extension is parallel to the axial direction of the housing, and the sampling hole is located at the end of the extension facing the connection end. A first protrusion extends from one end of the extension to the other end.
[0010] Alternatively, the first protrusion may include multiple protrusions, which are arranged sequentially at intervals along the length of the extension.
[0011] In some embodiments, a second protrusion is provided on the inner wall surface of the housing, the second protrusion being located between the free end and the end of the extension facing the free end.
[0012] In some embodiments, the second protrusion extends from the free end to the end of the extension facing the free end.
[0013] In some embodiments, a drainage groove is recessed on the inner wall surface of the housing, and the drainage groove is located at the bottom of the inner wall surface of the housing. The drainage groove extends from the free end to the connecting end.
[0014] In some embodiments, the depth of the drainage groove gradually decreases from the free end to the connection end.
[0015] In some embodiments, the slit divides the diaphragm into a body portion and a valve portion, with one side of the valve portion connected to the body portion and the remaining side of the valve portion surrounded by the slit.
[0016] The inner wall of the housing is also provided with two first structural members. Each first structural member has a first limiting surface, which is flush with the connecting end. The first limiting surfaces of the two first structural members are located on both sides of the valve portion, with a portion of the first limiting surface contacting the surface of the main body portion and the other portion of the first limiting surface contacting the surface of the valve portion.
[0017] In some embodiments, the first structural member is further provided with a second limiting surface, and there is an avoidance gap between the second limiting surface and the connecting end.
[0018] The clearance and the valve are opposite each other. The valve can deform and extend into the clearance, and the second limiting surface stops the valve.
[0019] In some embodiments, the first structural member extends from the connecting end to the free end, and a first gap is formed between the first structural member and the inner wall surface of the housing, the first gap being used to form a flow stabilization channel.
[0020] In some embodiments, one housing has a first mis-proof part at its connecting end, the diaphragm has a second mis-proof part, and the other housing has a third mis-proof part at its connecting end. The first, second, and third mis-proof parts are connected sequentially.
[0021] In some embodiments, the first anti-mistake part includes two first anti-mistake holes, both of which are recessed in the connection end of one of the housings, and the line connecting the centers of the two first anti-mistake holes is offset from the center of the circle containing the airflow channel.
[0022] The second error prevention part includes two second error prevention holes, which penetrate the membrane along the thickness direction of the membrane.
[0023] The third anti-mistake part includes two anti-mistake components, both of which protrude from the connection end of another housing.
[0024] The positions of the anti-mistake component, the first anti-mistake hole, and the second anti-mistake hole are corresponding in sequence, and the anti-mistake component passes through the first anti-mistake hole and the second anti-mistake hole.
[0025] In some embodiments, at least one housing has a receiving groove at its connecting end, and the connecting ends of the two housings and the diaphragm are bonded together with adhesive. The receiving groove is used to receive the overflow portion of the adhesive.
[0026] In some embodiments, the inner wall of the housing is further provided with a flow stabilizer, which has a flow stabilizing channel. One end of the flow stabilizing channel is connected to the sampling port, and the other end of the flow stabilizing channel is connected to the airflow channel. The extension is located inside the flow stabilizing channel.
[0027] In some embodiments, the current stabilizer includes two first structural members and a second structural member.
[0028] Two first structural members are located on both sides of the extension member, and one side of each first structural member is fixed to the inner wall surface of the housing. A first gap is formed between the first structural members and the inner wall surface of the housing.
[0029] The second structural member is disposed at the end of the extension member facing the free end, and its two sides are respectively fixed to the other sides of the two first structural members. A second gap is formed between the second structural member and the inner wall surface of the housing. The second gap is connected to the first gap, and the flow stabilization channel includes the first gap and the second gap.
[0030] In some embodiments, the second structural member is an inclined plate such that the height of the second gap gradually increases along the direction from the free end to the connection end.
[0031] The second aspect of this application provides a medical device including a breathing circuit and a flow sensor provided in the first aspect of this application, wherein the flow sensor is connected to the breathing circuit.
[0032] The flow sensor and medical device provided in this application, when installed in an anesthesia machine or ventilator, have the sampling port located at the top of the flow sensor, with the first protrusion positioned lower than the bottom of the sampling port. Therefore, when airflow flows from the airflow channel into the sampling port, the moisture carried by the gas condenses on the first protrusion. This prevents condensation from blocking the sampling port inlet, avoids condensation affecting the accuracy of the monitoring values, increases the control precision of tidal volume, and ensures that the tidal volume matches the set value, thereby protecting the patient's life. Attached Figure Description
[0033] To more clearly illustrate the technical solution of this application, the accompanying drawings used in the embodiments will be briefly described below.
[0034] Figure 1 This is a schematic diagram of the flow sensor provided in an embodiment of this application.
[0035] Figure 2 This is a cross-sectional view of the flow sensor provided in the embodiments of this application.
[0036] Figure 3 This is a schematic diagram of the housing of the flow sensor provided in an embodiment of this application.
[0037] Figure 4 yes Figure 3 Enlarged view of point A.
[0038] Figure 5 This is a structural schematic diagram of the housing of the flow sensor provided in an embodiment of this application from another perspective.
[0039] Figure 6 This is a perspective sectional view of the housing of the flow sensor provided in the embodiments of this application.
[0040] Figure 7 This is a schematic diagram of the diaphragm structure of the flow sensor provided in the embodiments of this application.
[0041] Figure 8 This is a partial cross-sectional structural diagram of the flow sensor provided in the embodiment of this application.
[0042] Figure 9 This is a schematic diagram of another housing of the flow sensor provided in this application embodiment.
[0043] Explanation of reference numerals in the attached drawings: 1000 - Flow sensor, 100 - Housing, 101 - Free end, 102 - Connecting end, 103 - Airflow channel, 104 - Sampling hole, 105 - Flow channel, 110 - Extension, 120 - First protrusion, 130 - Flow stabilizer, 131 - Flow stabilizer channel, 140 - First structural component, 141 - First gap, 142 - First limiting surface, 143 - Second limiting surface, 144 - Clearance gap, 145 - First plate , 146-Second plate, 150-Second structural component, 151-Second spacer, 160-Second protrusion, 170-First anti-mistake part, 171-First anti-mistake hole, 180-Third anti-mistake part, 181-Anti-mistake component, 190-Connector, 191-Receiving groove, 200-Diaphragm, 210-Gap, 220-Body part, 230-Valve part, 231-Arm bridge, 232-Moving part, 240-Second anti-mistake part, 241-Second anti-mistake hole. Detailed Implementation
[0044] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0045] This application provides a medical device, which can be an anesthesia machine or a ventilator. The medical device includes a breathing circuit and a flow sensor, with the flow sensor connected to the breathing circuit. The flow sensor can monitor the patient's expiratory and inspiratory flow rates and feed the monitored values back to the control system of the medical device, so that the control system can control parameters such as the patient's expiratory flow rate, inspiratory flow rate, and tidal volume in real time, so that the tidal volume meets the set value.
[0046] refer to Figure 1 and Figure 2 This application provides a flow sensor 1000, including a diaphragm 200 and two housings 100 connected to each other. In some embodiments, the housing 100 is cylindrical, that is, the cross-section of the housing 100 is circular. The diaphragm 200 is a circular sheet. In other embodiments, the diaphragm 200 may also be triangular, square, elliptical, or other regular shapes, or it may be irregular; this application does not impose any limitations. The cross-section of the housing 100 may also be triangular, square, elliptical, or other regular shapes, or it may be irregular; this application does not impose any limitations.
[0047] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 Each housing 100 includes a free end 101 and a connecting end 102 disposed opposite to each other. The free end 101 and the connecting end 102 are specifically located on opposite sides of the housing 100 along its length direction, and the length direction of the housing 100 is perpendicular to the cross-section of the housing 100. When the cross-section of the housing 100 is circular, its length direction is also its axial direction.
[0048] The housing 100 is provided with an airflow channel 103, which extends through the free end 101 and the connecting end 102. That is, the airflow channel 103 extends along the length of the housing 100, and the length of the airflow channel 103 is the same as the length of the housing 100. The airflow channel 103 is used for gas flow.
[0049] An extension 110 protrudes from the top of the inner wall of the housing 100, extending towards the center of the airflow channel 103. The housing 100 also has a sampling hole 104, which penetrates the extension 110 and the housing 100, and is connected to the airflow channel 103. Specifically, the sampling hole 104 penetrates the inner wall of the housing 100, the outer wall of the housing 100, one end of the extension 110 connected to the inner wall of the housing 100, and the end of the extension 110 away from the inner wall of the housing 100. That is, the sampling hole 104 extends radially along the housing 100. The sampling hole 104 is used for sampling equipment to sample the gas within the airflow channel 103, so as to detect the pressure of the gas within the airflow channel 103.
[0050] The extension 110 extends towards the center of the airflow channel 103, allowing the airflow at the center of the airflow channel 103 to be sampled, thereby improving the accuracy of pressure detection. Specifically, refer to... Figure 2 The extension 110 has a radial width of H1 along the housing 100, and the airflow channel 103 has a radius of R. H1 and R satisfy the following condition: 0.5R≤H1≤1.5R. The width of the extension 110 is within the above range, which allows the sampling hole 104 to sample the gas in the middle of the airflow channel 103, thereby increasing the accuracy of pressure detection.
[0051] A first protrusion 120 protrudes from the side of the extension 110 away from the inner wall of the housing 100. The first protrusion 120 is located around the sampling hole 104, and its position is lower than that of the sampling hole 104. The first protrusion 120 being located around the sampling hole 104 means that the distance between the closest point of the first protrusion 120 to the sampling hole 104 and the edge of the sampling hole 104 is less than 5 mm. The first protrusion 120 serves to guide condensate from the gas, preventing condensate from clogging the sampling hole 104.
[0052] refer to Figure 7 The diaphragm 200 has a slit 210 that extends through the diaphragm 200 along its thickness direction. The width and shape of the slit 210 can be designed according to actual needs; for example, the shape of the slit 210 can be circular, square, triangular, or elliptical, or a combination of multiple shapes. This application is not limited to these shapes.
[0053] A diaphragm 200 is disposed between two housings 100. The diaphragm 200 is attached to the connecting ends 102 of the two housings 100 on opposite sides along its thickness direction. A gap 210 connects the airflow channels 103 of the two housings 100. The diaphragm 200 and the connecting ends 102 of the housings 100 can be bonded together using adhesive. Alternatively, the diaphragm 200 can be disposed between the connecting ends 102 of the two housings 100, and then the connecting ends 102 of the two housings 100 can be connected by threads. Alternatively, the diaphragm 200 can be disposed between the connecting ends 102 of the two housings 100, and then the connecting ends 102 of the two housings 100 can be welded together.
[0054] The breathing circuit of medical devices includes an expiratory end and an inspiratory end. To detect a patient's expiratory and inspiratory flow rates, a flow sensor 1000 needs to be installed at each end. The detection principle of the flow sensors 1000 at both the expiratory and inspiratory ends is the same. The following explanation uses the flow sensor 1000 at the inspiratory end to detect inspiratory flow rate as an example; the detection principle of the flow sensor 1000 at the expiratory end will not be elaborated upon.
[0055] When the patient inhales, the gas enters the airflow channel 103 from the free end 101 of one of the housings 100, and then passes through the gap 210 of the diaphragm 200 from the airflow channel 103 into the airflow channel 103 of the other housing 100.
[0056] In each flow sensor 1000, the sampling holes 104 of the two housings 100 are connected to sampling devices. The gas in the airflow channel 103 flows to the sampling devices through the sampling holes 104, so that the two sampling devices can detect the pressure of the gas in the airflow channel 103 of the two housings 100 respectively. The pressure values of the gas in the airflow channel 103 of the two housings 100 are sampled and then processed by an analog signal processor and converted into flow rate.
[0057] In this embodiment, when the flow sensor 1000 is installed at the exhalation or inhalation end, the sampling hole 104 on the housing 100 faces upwards, meaning the sampling hole 104 is located at the top of the housing 100. The top end of the sampling hole 104 is located outside the housing 100, and the bottom end of the sampling hole 104 is located on the side of the extension 110 away from the inner wall surface of the housing 100. By providing a first protrusion 120 on the side of the extension 110 away from the inner wall surface of the housing 100, and positioning the first protrusion 120 around the bottom end of the sampling hole 104, water droplets condensed in the gas inside the sampling hole 104 will flow to the first protrusion 120 under gravity, thereby preventing condensate from blocking the sampling hole 104, ensuring the sampling hole 104 is unobstructed, and thus ensuring the accuracy of the detection results of the sampling device.
[0058] refer to Figure 3 , Figure 4 and Figure 6 In some embodiments, the length direction of the extension 110 is parallel to the axial direction of the housing 100, and the sampling hole 104 is located at the end of the extension 110 facing the connecting end 102; the first protrusion 120 extends from one end of the extension 110 to the other end. That is, the first protrusion 120 can be a continuous elongated strip. The longer the length of the first protrusion 120, the longer the contact time between the gas and the first protrusion 120, and the more moisture in the gas accumulates on the first protrusion 120. When the gas enters the airflow channel 103, it will first contact the end of the first protrusion 120 away from the sampling hole 104, and gradually flow along the first protrusion 120 towards the sampling hole 104. That is, when the gas flows to the end of the extension 110 near the free end 101, it begins to contact the first protrusion 120, increasing the contact time between the gas and the first protrusion 120. After the moisture in the gas condenses, it accumulates on the lower-positioned first protrusion 120 under the action of gravity, thereby preventing condensate from clogging the sampling hole 104.
[0059] The number of first protrusions 120 can be one or more. Taking three first protrusions 120 as an example, the three first protrusions 120 are arranged alternately, with one first protrusion 120 located in the middle of the side of the extension 110 away from the inner wall surface of the housing 100, and the other two first protrusions 120 located at the edge of the side of the extension 110 away from the inner wall surface of the housing 100. Furthermore, the height of the two first protrusions 120 located at the edge is greater than the height of the first protrusion 120 located in the middle.
[0060] In other embodiments, the first protrusion 120 includes multiple protrusions arranged sequentially at intervals along the length of the extension 110. The shape of the protrusions can be a regular shape such as a circle, ellipse, triangle, or symmetrical shape, or it can be an irregular shape; this application is not limited to this. When gas enters the airflow channel 103, it will first contact the protrusions away from the sampling hole 104, and then gradually contact the protrusions closer to the sampling hole 104. The moisture carried by the gas gradually condenses and flows to the protrusions under the action of gravity, thereby preventing condensate from clogging the sampling hole 104.
[0061] refer to Figure 3 , Figure 5 and Figure 6 In some embodiments, a second protrusion 160 is provided on the inner wall surface of the housing 100, and the second protrusion 160 is located between the free end 101 and the end of the extension 110 facing the free end 101. Gas enters the airflow channel 103 from the free end 101 and flows towards the connecting end 102. When it flows near the connecting end 102, some gas enters the sampling hole 104. By providing the second protrusion 160 between the free end 101 and the extension 110, the gas first contacts the second protrusion 160, causing the moisture carried by the gas to condense on the second protrusion 160. Then, when the gas flows to contact the first protrusion 120, the remaining moisture carried by the gas condenses on the first protrusion 120, so that the gas flowing to the sampling hole 104 carries very little moisture, thereby preventing condensation from clogging the sampling hole 104.
[0062] refer to Figure 3 , Figure 5 and Figure 6 In some embodiments, the second protrusion 160 extends from the free end 101 to the end of the extension 110 facing the free end 101. The second protrusion 160 can be a continuous strip or include a plurality of spaced protrusions. The longer the second protrusion 160 extends, the longer the gas contacts the second protrusion 160, thereby allowing more water vapor to condense on the second protrusion 160.
[0063] refer to Figure 2 and Figure 5In some embodiments, a drainage groove 105 is recessed on the inner wall surface of the housing 100, and the drainage groove 105 is located at the bottom of the inner wall surface of the housing 100; the drainage groove 105 extends from the free end 101 to the connecting end 102. After the moisture carried by the gas becomes condensate, it will drip into the drainage groove 105. The drainage groove 105 can discharge the condensate into the airflow channel 103, preventing the condensate from accumulating near the diaphragm 200 and affecting the opening and closing of the diaphragm 200.
[0064] In some embodiments, reference is made to Figure 2 From the free end 101 to the connecting end 102, the depth of the drainage groove 105 gradually decreases. That is, the bottom surface of the drainage groove 105 is inclined relative to the axial direction of the housing 100, and the end of the drainage groove 105 facing the free end 101 is lower, while the end of the drainage groove 105 facing the connecting end 102 is higher. This can increase the discharge speed of condensate and prevent condensate from accumulating around the diaphragm 200.
[0065] In some other embodiments, the depth of the drainage groove 105 may remain constant from the free end 101 to the connecting end 102.
[0066] In some embodiments, reference is made to Figure 4 , Figure 6 and Figure 7 The slit 210 divides the diaphragm 200 into a body portion 220 and a valve portion 230. One side of the valve portion 230 is connected to the body portion 220, and the other side of the valve portion 230 is surrounded by the slit 210.
[0067] The inner wall of the housing 100 is also provided with two first structural members 140; the first structural member 140 is provided with a first limiting surface 142, the first limiting surface 142 is flush with the connecting end 102; the first limiting surfaces 142 of the two first structural members 140 are located on both sides of the valve portion 230, and a part of the first limiting surface 142 contacts the surface of the main body portion 220, and the other part of the first limiting surface 142 contacts the surface of the valve portion 230.
[0068] The first structural member 140 includes a first plate 145 and a second plate 146 connected in an L-shape. The side of the first plate 145 away from the second plate 146 is fixed to the inner wall surface of the housing 100. The second plates 146 of the two first structural members 140 are spaced apart and opposite to each other. The first limiting surface 142 includes a first sub-surface and a second sub-surface. The first sub-surface is located at the end of the first plate 145 facing the connecting end 102, and the second sub-surface is located at the end of the second plate 146 facing the connecting end 102. The first sub-surface contacts the surface of the body portion 220, and the second sub-surface contacts the surface of the valve portion 230.
[0069] The valve portion 230 includes a bridge 231 and a movable portion 232. Figure 7A dashed line is used as the dividing line between the main body 220, the arm bridge 231, and the movable part 232. The arm bridge 231 is rectangular, and the movable part 232 is triangular. The valve part 230 is located in the middle of the main body 220. One short side of the arm bridge 231 is fixedly connected to the main body 220, and one side of the movable part 232 is fixedly connected to the other short side of the arm bridge 231. The two long sides of the arm bridge 231 and the remaining sides of the movable part 232 are surrounded by a slot 210.
[0070] The portion between the outer edge of the main body 220 and the inner edge of the main body 220 near the bridge arm contacts the first sub-surface. The two side edges of the end of the bridge arm away from the movable part 232 contact the second sub-surface.
[0071] Using the first limiting surfaces 142 of the two first structural members 140 to limit the two sides of the body part 220 along its thickness direction, that is, to clamp the body part 220 between the two first limiting surfaces 142, can prevent the body part 220 from deforming due to large flow of gas and ensure the structural stability of the diaphragm 200.
[0072] If the edge of the valve portion 230 deforms, it can easily lead to instability in the width of the gap 210, and the change in the width of the gap 210 will affect the sampling accuracy. In the embodiments of this application, the first limiting surfaces 142 of the two first structural members 140 also restrict the movement of the two side edges of the valve portion 230, which can prevent the edge of the valve portion 230 from deforming, thereby ensuring the stability of the width of the gap 210, improving the sampling accuracy, and extending the service life of the flow sensor 1000. The first limiting surfaces 142 only restrict the two side edges of the valve portion 230, but do not restrict the middle part of the valve portion 230, so that the middle part of the valve portion 230 can deform, thereby meeting the needs of large flow of gas.
[0073] refer to Figure 6 and Figure 7 In some embodiments, the first structural member 140 is further provided with a second limiting surface 143, and a clearance gap 144 is provided between the second limiting surface 143 and the connecting end 102. Specifically, the second limiting surface 143 is located at the end of the second plate 146 facing the connecting end 102, and the second limiting surface 143 and the second sub-surface are distributed in a stepped manner, forming the clearance gap 144. The clearance gap 144 is opposite to the valve portion 230, and the valve portion 230 can deform and extend into the clearance gap 144, with the second limiting surface 143 stopping the valve portion 230.
[0074] When the gas flow rate is low, all the gas in the airflow channel 103 of one housing 100 can flow through the gap 210 of the diaphragm 200 to the airflow channel 103 of the other housing 100. When the gas flow rate is high, the gap 210 of the diaphragm 200 can no longer meet the gas flow requirements. At this time, the valve 230 will open and extend into the clearance gap 144, allowing the large flow of gas to flow into the airflow channel 103 of the other housing 100. The greater the degree to which the valve 230 opens, the greater the gas pressure difference in the airflow channels 103 of the two housings 100. When the valve 230 deforms to a certain extent, it will contact the second limiting surface 143. That is, the second limiting surface 143 will prevent the valve 230 from deforming further, preventing the valve 230 from being over-deformed and unable to return to its original position. This allows the valve 230 to return to its original position for the next use, thereby extending the life of the flow sensor 1000.
[0075] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the first structural member 140 extends from the connecting end 102 to the free end 101. Specifically, the end of the first structural member 140 facing the free end 101 is flush with the end of the extension member 110 facing the free end 101. A first gap 141 is formed between the first structural member 140 and the inner wall surface of the housing 100, and the first gap 141 is used to form a flow stabilizing channel 131. The first limiting surface 142 and the flow stabilizing channel 131 share the first structural member 140, which can reduce the number of parts in the flow sensor 1000 and simplify the structure of the flow sensor 1000.
[0076] In some embodiments, reference is made to Figure 3 One of the housings 100 has a first anti-fooling part 170 at its connecting end 102, for reference. Figure 7 The diaphragm 200 is provided with a second foolproof part 240, for reference. Figure 9 The connecting end 102 of the other housing 100 is provided with a third anti-mistake part 180; the first anti-mistake part 170, the second anti-mistake part 240, and the third anti-mistake part 180 are connected in sequence. The first anti-mistake part 170, the second anti-mistake part 240, and the third anti-mistake part 180 cooperate to ensure that the connecting ends 102 of the two housings 100 are connected to each other when the two housings 100 are installed. This avoids the housings 100 being installed in reverse, that is, it avoids connecting the free ends 101 of the two housings 100 to each other, and it also avoids connecting the free end 101 of one housing 100 to the connecting end 102 of the other housing 100 to each other.
[0077] In some embodiments, reference is made to Figure 9The first anti-mistake part 170 includes two first anti-mistake holes 171, both of which are recessed in the connecting end 102 of one of the housings 100. The line connecting the centers of the two first anti-mistake holes 171 is offset from the center of the circle containing the airflow channel 103. (Reference) Figure 7 The second anti-mistake part 240 includes two second anti-mistake holes 241, both of which penetrate the diaphragm 200 along its thickness direction. (Reference) Figure 3 The third anti-mistake part 180 includes two anti-mistake components 181, both of which protrude from the connection end 102 of another housing 100; the positions of the anti-mistake component 181, the first anti-mistake hole 171 and the second anti-mistake hole 241 are corresponding in sequence, and the anti-mistake component 181 passes through the first anti-mistake hole 171 and the second anti-mistake hole 241.
[0078] The first anti-mistake hole 171 and the second anti-mistake hole 241 can be in the shape of a regular shape such as a circle, square, triangle, or ellipse, or they can be irregular shapes. The shape of the anti-mistake component 181 is the same as that of the first anti-mistake hole 171. By setting the anti-mistake part as an anti-mistake hole and an anti-mistake component 181, the structure is simple and easy to connect.
[0079] In addition, the line connecting the centers of the two first anti-fool holes 171 and the center of the circle containing the airflow channel 103 are offset, which can ensure that the extensions 110 of the two housings 100 are in the same direction and avoid the extensions 110 of the two housings 100 being in opposite directions.
[0080] refer to Figure 3 and Figure 6 In some embodiments, at least one housing 100 has a receiving groove 191 at its connecting end 102. The connecting ends 102 of the two housings 100 and the diaphragm 200 are bonded and fixed together with adhesive. The receiving groove 191 is used to accommodate any overflow of adhesive. The receiving groove 191 can prevent adhesive overflow and avoid the adhesive from affecting the performance of the flow sensor 1000.
[0081] refer to Figure 6 and Figure 8In some embodiments, one of the housing 100's connecting ends 102 is provided with a connector 190, which surrounds the housing 100, facilitating the connection of the two housings 100. When adhesive is used to bond the connecting ends 102 of the two housings 100 and the diaphragm 200, the connecting end 102 of the housing 100 without the connector 190 extends into the connector 190, and the gap 210 between the outer wall surface of the housing 100 and the inner wall surface of the connector 190 can accommodate overflowing adhesive. Alternatively, the connecting end 102 of the housing 100 without the connector 190 extends into the connector 190, allowing the outer wall surface of the housing 100 and the inner wall surface of the connector 190 to be welded. Alternatively, an internal thread may be avoided in the connector 190, and an external thread may be provided on the outer wall of the housing 100 without the connector 190. The connecting end 102 of the housing 100 without the connector 190 may extend into the connector 190, and the internal and external threads may be screwed together to fix the two housings 100 together.
[0082] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the inner wall of the housing 100 is further provided with a flow stabilizer 130, which has a flow stabilizing channel 131. One end of the flow stabilizing channel 131 is connected to the sampling port 104, and the other end is connected to the airflow channel 103. The extension 110 is located inside the flow stabilizing channel 131. Gas first enters the airflow channel 103, then enters the flow stabilizing channel 131 from the airflow channel 103, and then enters the sampling port 104 from the flow stabilizing channel 131. The flow stabilizing channel 131 can guide gas into the sampling port 104 and stabilize the pressure of the gas entering the sampling port 104, thereby increasing the accuracy of pressure measurement.
[0083] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the flow stabilizer 130 includes two first structural members 140 and a second structural member 150. The two first structural members 140 are respectively located on both sides of the extension 110, and one side of each of the two first structural members 140 is fixed to the inner wall surface of the housing 100. A first gap 141 is formed between the first structural members 140 and the inner wall surface of the housing 100. Specifically, the first gap 141 is formed between the first plate 145 of the first structural member 140 and the inner wall surface of the housing 100. The extension 110 is located within the gap between the second plates 146 of the two first structural members 140, and the two second plates 146 are spaced apart from the opposite sides of the extension 110.
[0084] The second structural member 150 is disposed at one end of the extension 110 facing the free end 101, and both sides of the second structural member 150 are respectively fixed to the other side of the two first structural members 140. Specifically, both sides of the second structural member 150 are respectively fixed to the side of the second plate 146 away from the first plate 145. A second gap 151 is formed between the second structural member 150 and the inner wall surface of the housing 100. The second gap 151 communicates with the first gap 141, and the flow stabilizing channel 131 includes the first gap 141 and the second gap 151. It can be seen that, in addition to being provided with the first limiting surface 142, the second limiting surface 143 and the clearance gap 144, the first structural member 140 is also used to form the flow stabilizing member 130, reducing the number of parts in the flow sensor 1000. Furthermore, the flow stabilizing member 130 is shaped like an "airplane nose", with a simple structure, easy to process, and can accurately guide the gas into the sampling hole 104.
[0085] refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the second structural member 150 is an inclined plate, such that the height of the second interval 151 gradually increases along the direction from the free end 101 to the connecting end 102. As the height of the second interval 151 increases, the airflow tends to be smoother, which can increase the stability of the gas pressure and increase the accuracy of the sampled gas pressure.
[0086] The embodiments of this application have been described in detail above. Specific examples have been used in this article to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and central idea of this application.
Claims
1. A flow sensor, characterized in that, include: A diaphragm and two shells connected to each other; Each of the housings includes a free end and a connecting end disposed opposite to each other; the housing is provided with an airflow channel and a sampling hole, the airflow channel passing through the free end and the connecting end, and an extension protruding from the top of the inner wall of the housing, the extension extending toward the center of the airflow channel; The sampling hole penetrates the extension and the housing, and the sampling hole is connected to the airflow channel; a first protrusion is provided on the inner wall side of the extension away from the housing, the first protrusion is located around the sampling hole, and the position of the first protrusion is lower than the position of the sampling hole; The diaphragm has a slit that extends through the diaphragm along its thickness direction; The diaphragm is disposed between the two housings, and the two opposite sides of the diaphragm along its thickness direction are respectively attached to the connecting ends of the two housings, and the gap connects the airflow channels of the two housings.
2. The flow sensor according to claim 1, characterized in that, The length direction of the extension is parallel to the axial direction of the housing, and the sampling hole is located at one end of the extension facing the connecting end; the first protrusion extends from one end of the extension to the other end. Alternatively, the first protrusion may include a plurality of protrusions, which are arranged sequentially at intervals along the length of the extension.
3. The flow sensor according to claim 2, characterized in that, The inner wall surface of the housing has a second protrusion, which is located between the free end and the end of the extension facing the free end.
4. The flow sensor according to claim 1, characterized in that, The inner wall of the housing is recessed with a drainage groove, which is located at the bottom of the inner wall of the housing; the drainage groove extends from the free end to the connecting end.
5. The flow sensor according to any one of claims 1 to 4, characterized in that, The slit divides the diaphragm into a body portion and a valve portion, with one side of the valve portion connected to the body portion and the remaining side of the valve portion surrounded by the slit; The inner wall of the housing is also provided with two first structural members; the first structural members are provided with first limiting surfaces, which are flush with the connecting end; the first limiting surfaces of the two first structural members are located on both sides of the valve portion, and a part of the first limiting surface contacts the surface of the body portion, while the other part of the first limiting surface contacts the surface of the valve portion.
6. The flow sensor according to claim 5, characterized in that, The first structural component is also provided with a second limiting surface, and there is an avoidance gap between the second limiting surface and the connecting end; The clearance gap and the valve portion are opposite each other. The valve portion can deform and extend into the clearance gap. The second limiting surface stops the valve portion.
7. The flow sensor according to claim 5, characterized in that, The first structural member extends from the connecting end to the free end, and a first gap is formed between the first structural member and the inner wall surface of the housing, the first gap being used to form a stable flow channel.
8. The flow sensor according to any one of claims 1 to 4, characterized in that, One of the housings has a first anti-mistake part at its connecting end, the diaphragm has a second anti-mistake part, and the other housing has a third anti-mistake part at its connecting end; the first anti-mistake part, the second anti-mistake part, and the third anti-mistake part are connected in sequence.
9. The flow sensor according to claim 8, characterized in that, The first anti-mistake part includes two first anti-mistake holes, both of which are recessed in the connection end of one of the housings, and the line connecting the centers of the two first anti-mistake holes is offset from the center of the circle in which the airflow channel is located. The second anti-mistake part includes two second anti-mistake holes, both of which penetrate the membrane along the thickness direction of the membrane; The third anti-mistake part includes two anti-mistake components, both of which protrude from the connection end of the other housing. The positions of the error-proof component, the first error-proof hole, and the second error-proof hole are corresponding in sequence, and the error-proof component passes through the first error-proof hole and the second error-proof hole.
10. The flow sensor according to any one of claims 1 to 4, characterized in that, The inner wall of the housing is also provided with a flow stabilizer, the flow stabilizer is provided with a flow stabilizer channel, one end of the flow stabilizer channel is connected to the sampling hole, and the other end of the flow stabilizer channel is connected to the airflow channel; the extension is located inside the flow stabilizer channel.
11. The flow sensor according to claim 10, characterized in that, The current stabilizing component includes two first structural components and a second structural component; The two first structural members are respectively located on both sides of the extension member, and one side of each of the two first structural members is fixed to the inner wall surface of the housing; a first gap is formed between the first structural members and the inner wall surface of the housing; The second structural member is disposed at one end of the extension member facing the free end, and the two sides of the second structural member are respectively fixed to the other side of the two first structural members; a second gap is formed between the second structural member and the inner wall surface of the housing; the second gap and the first gap are connected, and the flow stabilization channel includes the first gap and the second gap.
12. A medical device, characterized in that, It includes a breathing circuit and a flow sensor according to any one of claims 1 to 11, wherein the flow sensor is connected to the breathing circuit.