WO2023165386A1 - Gear-adjustable constant flow valve, and measurement apparatus - Google Patents

Abstract

A gear-adjustable constant flow valve, and a measurement apparatus. The gear-adjustable constant flow valve (1) comprises: a first valve body (11), a first gear portion (112) and a second gear portion (113) being provided on an inner wall of the first valve body (11); a second valve body (12), the first valve body (11) and the second valve body (12) cooperating with each other to form an airflow channel (111), and the first valve body (11) being capable of moving relative to the second valve body (12); and a valve flap (13), the valve flap (13) being arranged in the airflow channel (111), the valve flap (13) being provided with a free end (131) and a fixed end (132), and the free end (131) being capable of rotating around the fixed end (132), wherein as the pressure difference between two sides of the valve flap (13) gradually increases, the rotation angle of the valve flap (13) increases, and the distance between the free end (131) and the first gear portion (112) or the second gear portion (113) gradually decreases; and the valve flap (13) can be arranged opposite the first gear portion (112) or the second gear portion (113) by moving the first valve body (11), so that the airflow channel (111) is in a first gear state or a second gear state, and the flow of a first airflow through the airflow channel (111) in the first gear state is different from the flow of a second airflow through the airflow channel (111) in the second gear state. The constant flow valve can control the flow at a plurality of gears, a gear shift can be directly realized in one gear-adjustable constant flow valve, and thus the gear-adjustable constant flow valve is simple and easy to operate.

Description

Adjustable gear constant flow valve and testing equipment

This application claims the priority of the Chinese patent application with the application number 202210195442.0 and the title of the invention "Constant flow valve and detection equipment with adjustable gear position" submitted to the China Patent Office on March 1, 2022, the entire contents of which are incorporated by reference in this application.

technical field

The present application relates to the technical field of medical detection, in particular to a constant flow valve with adjustable gears and detection equipment.

Background technique

Exhaled nitric oxide (FeNO) is produced by airway cells, and the concentration of exhaled nitric oxide (FeNO) is related to the number of inflammatory cells, which can reflect the human respiratory inflammation. Therefore, exhaled nitric oxide (FeNO) test can be used for Pre-diagnose the inflammation of the respiratory tract and identify respiratory diseases such as asthma. The exhaled nitric oxide (FeNO) test requires a person to exhale a steady airflow of 50±5ml/s and 200±20ml/s at an exhalation pressure of at least 5cmH2O (water) to detect lower respiratory tract and lung diseases respectively. However, for children and patients with respiratory diseases, it is difficult to exhale a constant flow of airflow, and certain measures need to be taken to assist the human body to easily exhale a constant flow of airflow.

Contents of the invention

The present application provides a constant flow valve with adjustable gears. The constant flow valve with adjustable gears includes: a first valve body, the first valve body has an inner wall, and the inner wall is provided with a first gear part and the second gear part; the second valve body, the first valve body cooperates with the second valve body to form an airflow channel, and the first valve body can move relative to the second valve body; A valve disc, the valve disc is arranged in the air flow channel, the valve disc is provided with a free end and a fixed end, and the free end can rotate around the fixed end; wherein, the air flow channel is provided with an air inlet and a fixed end. Air outlet, the direction from the air inlet to the air outlet, as the pressure difference on both sides of the valve flap gradually increases, the rotation angle of the valve flap increases, and the free end and the first The distance between the shift portion or the second shift portion decreases gradually; by moving the first valve body, the valve flap can be opposite to the first shift portion or the second shift portion It is set so that the air flow channel is in the first gear state or the second gear state, the first air flow rate passing through the air flow channel in the first gear state is different from that in the second gear state The flow rates of the second airflow that can pass through the airflow channels are different.

In this application, the valve flap is installed in the airflow channel, and the user exhales toward the airflow channel. Air pressure changes the rotation angle of the valve disc in the air flow channel to change the area of the air flow channel blocked by the valve disc along the flow direction of the air flow, thereby changing the flow area of the air flow in the air flow channel. That is, when the user's exhalation pressure increases, the pressure difference between the front and rear sides of the valve disc increases, the rotation angle of the valve disc in the airflow channel increases, and the area occupied by the valve disc in the airflow channel increases, resulting in the airflow channel The flow area of the internal air flow decreases; when the user exhales pressure, the pressure difference between the front and rear sides of the valve disc decreases, the rotation angle of the valve disc in the air flow channel decreases, and the area occupied by the valve disc in the air flow channel decreases , leading to a reduction in the flow area of the airflow in the airflow channel. The air flow discharged from the air flow channel to the detection device can be controlled by the relationship between the air pressure difference between the front and rear sides of the valve disc in the air flow channel and the air flow area, so that a constant air flow out of the air flow channel can be kept as much as possible so that the user can quickly blow the air. The specified flow rate is increased to improve the reliability of exhaled breath detection.

Moreover, the constant flow valve with adjustable gear position can also be provided with a gear position, and the valve disc is set opposite to the gear position. After the user exhales toward the air flow channel, the air flow rate discharged from the air flow channel to the detection device remains constant. gear status. Alternatively, the constant flow valve with adjustable gears can also be provided with three or more gears, that is, the first gear, the second gear, the third gear, the third gear, etc. are set on the first valve body. For multiple gears such as four gears, moving the first valve body can make the valve disc correspond to one of the gears, so that the air flow channel 111 is in the first gear state or the second gear state or the third position state or the Nth gear state, etc., and the air flow rate passing through the airflow channel 111 is different in each gear state. For example, the air flow rate corresponding to the first gear part is 50ml/s±10%, and the air flow rate corresponding to the second gear part is 200ml/s±10%. When the valve flap is set opposite to the first gear part, the airflow channel is in the first gear state, and after the user exhales into the airflow channel, the air flow rate discharged from the airflow channel to the detection device remains at 50ml/s±10%. When the first valve body is moved and the valve disc is set opposite to the second gear, the airflow channel is in the second gear position. After the user exhales toward the airflow channel, the air flow rate discharged from the airflow channel to the detection device remains at 200ml/s ±10%. In this embodiment, the constant flow valve with adjustable gears can be set with multiple gears to control the flow of multiple gears, and the gear shift can be directly realized in one constant flow valve with adjustable gears, which is easy and convenient to operate.

In a possible design, the first gear part includes a first curved surface, and the distance between the first curved surface and the valve flap gradually increases from the air inlet to the air outlet, And during the rotation process of the valve flap corresponding to the first curved surface, the flow rate of the first airflow in the airflow channel remains unchanged;

The second gear part includes a second curved surface, and the distance from the second curved surface to the valve flap gradually decreases from the air inlet to the air outlet, and the valve flap corresponds to the During the rotation process of the second curved surface, the flow rate of the second airflow in the airflow channel remains unchanged;

The first curved surface is connected to the near end of the second curved surface, and the first curved surface is closer to the valve disc relative to the second curved surface.

In this application, the slope of the first curved surface gradually decreases from the air inlet to the air outlet, through the change of the curvature of the first curved surface, to match the angle change during the rotation of the valve clack and to allow the flow of airflow in the airflow channel The airflow area to ensure a constant airflow out of the airflow channel as much as possible. From the air inlet to the air outlet, the slope of the second curved surface gradually increases, through the change of the curvature of the second curved surface, to match the angle change during the rotation of the valve flap and the airflow area in the airflow channel that can circulate the airflow, To ensure a constant airflow out of the airflow channel as much as possible.

In a possible design, the shape variation law of the first curved surface and the second curved surface conforms to Formula 1 and Formula 2;

In the formula, Q is the flow rate, C is the throttling coefficient, A is the flow area, ΔP is the pressure difference between the front and rear sides of the valve disc, ρ is the fluid density, L is the width of the air flow channel, d is the distance between the valve disc and the side wall of the air flow channel, and H is The height of the air flow channel, B is the length of the disc, and θ is the rotation angle of the disc. Among them, θ is the angle at which the pressure difference pushes the disc to balance with the first elastic member, and the stiffness of the first elastic member is set by simulation to fit the height H of the air flow channel.

In a possible design, the gear-adjustable constant flow valve includes a first elastic member, and one of the first elastic members One end is connected to the valve flap, and the other end of the first elastic member is connected to the second valve body;

When the airflow flows through the airflow channel, the airflow can overcome the elastic force of the first elastic member to push the valve clack to rotate;

When there is no airflow in the airflow channel, the first elastic member drives the valve clack to reset by its resilience force.

In this application, during the process of the airflow pushing the valve clack to rotate, the valve clack can overcome the reverse thrust applied by the first elastic member to rotate, and the force of the airflow is balanced with the elastic force of the first elastic member; when the airflow disappears, the valve clack will The thrust force of the first elastic member disappears, and the first elastic member pushes the valve clack back to the initial position through its own elastic force, and the structure is simple. When the valve clack is in balance with the first elastic member, the angle between the valve clack and the second valve body is not greater than 90°.

Wherein, the first elastic member may be a torsion spring.

In a possible design, the gear-adjustable constant flow valve further includes a seal, and the seal seals a connection position between the first valve body and the second valve body.

In the present application, the airtightness of the airflow channel is ensured by the sealing member, which reduces the risk of part of the airflow in the airflow channel leaking along the gap where there is a gap at the connection position between the first valve body and the second valve body. The sealing member can be a rubber ring, and a sealing ring is placed on the outer ring of the first valve body or the second valve body, or sealing oil is provided at the connecting position of the first valve body and the second valve body.

In a possible design, the first valve body is connected to the second valve body along the height direction of the gear-adjustable constant flow valve to form the airflow channel.

In this application, the first valve body and the second valve body have a U-shaped structure, and the two are spliced to form an air flow channel. After the first valve body and the second valve body are spliced, the first valve body can move relative to the second valve body. The first valve body realizes gear shifting. The first valve body and the second valve body are connected by splicing, which facilitates their assembly. The first valve body and the second valve body may also be connected by other connection methods, which are not limited in this embodiment.

In a possible design, the constant flow valve with adjustable gears further includes a pusher, and the constant flow valve with adjustable gears also includes a pusher. When the pusher is pushed, the pusher can drive the first valve body to move.

In the present application, the pusher and the first valve body may be fixedly connected, and the pusher is pushed so that the pusher drives the first valve body to move relative to the second valve body, thereby realizing shifting of gears. Wherein, the pushing member and the first valve body may be fixedly connected in the direction of buckle or thread.

Alternatively, the pusher is provided with a slider, and the first valve body is provided with a slideway matched with the slideway, and the slider can slide along the slideway. When the slider moves to abut against the side wall of the slideway, the pusher drives the first A valve body movement.

In a possible design, the constant flow valve with adjustable gears includes a casing, the first valve body and the second valve body are installed in the casing, and the first valve body can described shell movement;

The constant flow valve with adjustable gear also includes a first limiter and a second limiter, the first limiter and the second limiter are installed on the housing, and the first valve The body is provided with a first matching portion and a second matching portion;

When the first limiting part cooperates with the first matching part, the air flow channel is in the first gear state; when the second limiting part cooperates with the second matching part, the airflow channel The channel is in the second gear state.

In the present application, the housing is provided with an opening, at least part of the pusher extends out of the housing along the opening, and the pusher can slide along the opening to drive the first valve body to move. The first limiting part and the second limiting part are connected to the inner wall of the shell, and the pushing part is located between the first limiting part and the second limiting part. The first matching portion and the second matching portion are arranged on the outer wall of the first valve body. When the first limiting member cooperates with the first fitting part, the valve flap is opposite to the first gear part, so that the air flow channel is in the first gear state. Move the first valve body, the first stopper is separated from the first matching part, and the second stopper is matched with the second matching part, and the valve flap is opposite to the second gear part, so that the air flow channel is in the second gear bit state. Among them, the distance between the first limiter and the second limiter The distance is smaller than the distance between the first matching portion and the second matching portion. Through the cooperation of the first limiter and the first matching part, the cooperation of the second limiter and the second matching part, the user is prompted to reach the shift position, and the first valve body is restricted from continuing to move, so as to ensure the air flow when the user exhales The channel is always in this gear state to keep the air flow channel out of the airflow channel as constant as possible. When shifting gears, the first limiting member can be disengaged from the first matching portion or the second limiting member can be disengaged from the second matching portion only by slightly increasing the driving force, so as to achieve the effect of displacement adjustment.

When the distance between the first fitting part and the second fitting part is long and the stroke of the pusher is greater than the displacement of the pipe, the length of the slideway can be increased so that the slider slides along the slideway for a period of time. Invalid displacement, when the slider abuts against the side wall of the slideway, the slider pushes the first valve body to move.

Specifically, the first limiting part and the second limiting part may be bent elastic pieces, the limiting part of the elastic part is a tapered structure, and the first matching part and the second matching part are grooves. When the first valve body is moved, the side wall of the groove squeezes the elastic piece to make the elastic piece break away from the groove, and the elastic piece is always in a compressed state during the movement of the first valve body. When the other groove moves under the other elastic piece, the elastic piece is partially locked in the groove by its own elastic force.

Alternatively, the first limiting member and the second limiting member are spheres, and the housing has an accommodation cavity for placing the sphere, the sphere can roll in the accommodating cavity, and the opening of the accommodating cavity is smaller than the diameter of the sphere, so as to limit the falling of the sphere. The depth is greater than the diameter of the sphere, so that the sphere can be retracted into the receiving chamber. When the first valve body is moved, the ball can be retracted into the accommodation cavity, and when the first stopper (second stopper) cooperates with the first fitting part (second fitting part), part of the ball falls into the groove .

In a possible design, at least part of the second valve body is sheathed on the first valve body along the flow direction of the air flow to form the air flow channel.

In the present application, the first valve body is nested in the second valve body, and the shifting of gears is realized by changing the depth at which the first valve body enters the second valve body. Wherein, the first valve body can be a fixed part, and the second valve body can be moved to switch gears, or the second valve body can be a fixed part, and the first valve body can be moved to switch gears, and the second valve body can be pushed without setting other matching parts. A valve body or a second valve body reduces manufacturing cost.

In a possible design, the constant flow valve with adjustable gear further includes a third limiter, the third limiter is connected with the second valve body, and the first valve body is provided with The third matching part and the fourth matching part;

When the third limiting member cooperates with the third matching portion, the airflow channel is in the first gear state, and when the third limiting member cooperates with the fourth matching portion, the airflow passage The channel is in the second gear state.

In the present application, the third matching portion and the fourth matching portion are arranged on the outer wall of the first valve body. When the third limiting part cooperates with the third fitting part, the valve disc is opposite to the first gear part, so that the air flow channel is in the first gear state. Move the first valve body, the third stopper is separated from the third fitting part, and the third stopper is moved to the fourth fitting part along with the first valve body, so that the third stopper is matched with the fourth fitting part, and the valve The flap is opposite to the second gear part, so that the air flow channel is in the second gear state. Through the cooperation between the third limiter and the third matching part, and the cooperation between the third limiter and the fourth matching part, the user is prompted to reach the shift position, and the first valve body is restricted from continuing to move, so as to ensure the air flow when the user exhales The channel is always in this gear state to keep the air flow channel out of the airflow channel as constant as possible. When shifting gears, the third limiting member can be disengaged from the third matching portion or the fourth matching portion only by slightly increasing the driving force.

In a possible design, the second valve body is provided with a receiving groove, and the third limiting member is arranged in the receiving groove;

During the movement of the first valve body, the third limiting member shrinks into the receiving groove;

When the airflow channel is in the first gear state or the second gear state, at least a part of the third limiting member is engaged with the third matching portion or the fourth matching portion.

In this application, when the first valve body needs to be shifted (such as shifting from the first gear state to the second gear state), the side wall of the third matching part pushes the third stopper out and shrinks into the receiving groove. During the movement of the first valve body, the third stopper abuts against the outer wall of the first valve body and shrinks into the receiving groove all the time, and when the fourth fitting part moves below the third stopper, the third stopper The whereabouts of the bit parts are set at the fourth matching part. By setting the accommodating groove, when the third limiting member is not clamped on the third fitting portion or the fourth fitting portion, it is set in the accommodating groove, thereby no need to provide a movement space for the third limiting member, reducing possible The overall volume of the constant flow valve for gear adjustment is convenient for storage.

Wherein, the third limiting member may include a limiting block and a spring, one end of the spring is connected to the bottom wall of the receiving groove, the other end of the spring is connected to the limiting block, and the third matching portion and the fourth matching portion are grooves. When the first valve body is moved, the side wall of the groove pushes the limit block out of the groove, and at the same time the limit block presses the spring. When the other groove moves below the limit block, the limit block does not press against the spring, and the spring pushes the limit block into the groove by its resilience. Alternatively, the third limiting member is a sphere, the sphere can roll in the holding groove, the opening of the holding groove is smaller than the diameter of the sphere to limit the falling of the sphere, and the depth of the accommodating groove is greater than the diameter of the sphere, so that the sphere can shrink into the holding groove Inside. When the first valve body is moved, the sphere can be retracted into the receiving groove, and when the third limiting part cooperates with the third matching part (fourth matching part), part of the sphere falls into the groove.

The present application also provides a detection device for detecting nitric oxide content, the detection device comprising:

A constant flow valve with adjustable gear position, the constant flow valve is the above-mentioned constant flow valve with adjustable gear position;

A detection device, the detection device is used to detect the gas passing through the constant flow valve.

It is to be understood that both the foregoing general description and the following detailed description are exemplary only and are not restrictive of the application.

Description of drawings

FIG. 1 is a schematic structural view of a specific embodiment of a constant flow valve with adjustable gears provided by the present application;

Fig. 2 is a schematic diagram of part of the structure in Fig. 1;

Fig. 3 is a schematic cross-sectional view of the constant flow valve with adjustable gear position in the first gear position in Fig. 1;

Fig. 4 is a schematic cross-sectional view of the constant flow valve with adjustable gear position in the second gear position in Fig. 1;

Fig. 5 is a schematic cross-sectional view of the constant flow valve with adjustable gears provided by the present application in the first gear state in another specific embodiment;

Fig. 6 is a schematic cross-sectional view of the constant flow valve with adjustable gear position in the second gear position in Fig. 5;

Fig. 7 is a simple cross-sectional schematic diagram of a constant flow valve with adjustable gears provided by the present application;

Fig. 8 is a schematic diagram of the detection equipment provided in the present application.

Reference signs:

1-constant flow valve with adjustable gear position, 11-first valve body, 111-air flow channel, 111a-inlet port, 111b-air outlet port, 112-first gear part, 113-second gear part, 114-first fitting part, 115-second fitting part, 116-third fitting part, 117-fourth fitting part, 12-second valve body, 121-accommodating groove, 13-disc, 131-free end, 132-fixed end, 14-first elastic member, 15-pushing member, 16-shell, 17-first limiting member, 18-second limiting member, 19-third limiting member;

2- detection equipment, 21- detection device;

L-air flow channel width, d-valve disc and air channel side wall distance, H-air flow channel height, B-valve disc height, θ-valve disc rotation angle.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description serve to explain the principles of the application.

Detailed ways

In order to better understand the technical solutions of the present application, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

Terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of this application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

It should be understood that the term "and/or" used herein is only an association relationship describing associated objects, which means that there may be three relationships, for example, A and/or B, which may mean that A exists alone, and A and B exist simultaneously. B, there are three situations of B alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

It should be noted that the orientation words such as "up", "down", "left", and "right" described in the embodiments of the present application are described from the angles shown in the drawings, and should not be interpreted as limiting the implementation of the present application. Example limitations. Furthermore, in this context, it also needs to be understood that when it is mentioned that an element is connected "on" or "under" another element, it can not only be directly connected "on" or "under" another element, but can also To be indirectly connected "on" or "under" another element through an intervening element.

Exhaled nitric oxide (FeNO) is produced by airway cells and is a biomarker of airway inflammation. It is widely used in the diagnosis and treatment of respiratory diseases and the identification of respiratory diseases such as asthma. The exhaled nitric oxide (FeNO) test requires a person to exhale a steady airflow of 50±5ml/s and 200±20ml/s at an exhalation pressure of at least 5cmH2O (water) to detect lower respiratory tract and lung diseases respectively. However, for children and patients with respiratory diseases, it is difficult to exhale a constant flow of airflow, and certain measures need to be taken to assist the human body to easily exhale a constant flow of airflow.

The existing way to keep the user exhaling a constant airflow is to adjust the expiratory airflow according to the user's own reaction ability according to the device's feedback on the image and sound of the airflow change. However, some users who adopt this method will have a certain hysteresis due to poor self-response ability, and when they receive feedback for adjustment, their own exhalation control ability will be insufficient, causing the expiratory flow to exceed in a short period of time. or below the desired flow range. Although this method can prompt the user to control the expiratory flow, it involves a high degree of user participation, low reliability, and unstable expiratory flow.

There is also an electronically controlled air flow adjustment device, which obtains the flow rate in the pipeline through the sensor, and after the data is sent back for processing, the motor is controlled to adjust the opening of the valve, so that the user's exhalation flow can be stabilized in a range Inside. However, when the user starts blowing with a larger exhalation pressure, the motor will be turned off to the minimum state, causing the user to be difficult to exhale continuously due to the excessive air resistance. In addition, for the air flow detection device, realizing the constant current function with a complete electric drive control system will lead to a significant increase in cost.

There are also constant flow valves with self-operated adjustable gears, which can realize the control of exhalation flow through mechanical methods. With the help of the pressure difference between the inlet and outlet of the adjustable gear constant flow valve, the flow area of the pipeline is changed by deforming/displacing the valve disc, so as to achieve the effect of controlling the air flow. However, the existing constant flow valves with adjustable gears need to rely on the pressure difference to generate deformation/displacement inside, often requiring multiple structural components to be installed inside the pipeline, and the working principle and structure are relatively complicated. Moreover, the existing constant flow valve with adjustable gear can only control the flow of one gear, and two constant flow valves with adjustable gear may be needed to meet the detection of exhaled nitric oxide (FeNO) at 50ml/s and 200ml The two gears of /s require that not only the cost will be all Improvement is also unfavorable for the portability of the exhaled nitric oxide (FeNO) detection device.

In order to solve the above technical problems, this embodiment provides a detection device, which is a nitric oxide content detection device, including a constant flow valve 1 with an adjustable gear position and a detection device, and the constant flow valve 1 with an adjustable gear position It is connected with the detection device so that the gas flowing out along the adjustable constant flow valve 1 can enter the detection device for detection.

As shown in Figures 1 and 2, the constant flow valve 1 with adjustable gears includes a first valve body 11, a second valve body 12 and a valve flap 13, the first valve body 11 has an inner wall, and the inner wall is provided with a first gear position Part 112 and second gear part 113, the first valve body 11 cooperates with the second valve body 12 to form an air flow passage 111, and the first valve body 11 can move relative to the second valve body 12; the valve flap 13 is arranged in the air flow passage 111 , the valve flap 13 is provided with a free end 131 and a fixed end 132 , and the free end 131 can rotate around the fixed end 132 . Wherein, the air flow channel 111 is provided with an air inlet 111a and an air outlet 111b. From the air inlet 111a to the air outlet 111b, as the pressure difference on both sides of the valve disc 13 gradually increases, the rotation angle of the valve disc 13 increases. The distance between the free end 131 and the first shift portion 112 or the second shift portion 113 decreases gradually. By moving the first valve body 11, the valve disc 13 can be arranged opposite to the first gear part 112 or the second gear part 113, so that the air flow channel 111 is in the first gear state or the second gear state, and the first gear position The first air flow rate passing through the air flow channel 111 in the state is different from the second air flow rate passing through the air flow channel 111 in the second gear state.

In this embodiment, the valve flap 13 is installed in the airflow passage 111, and the user exhales toward the airflow passage 111, and the air pressure acts on the airflow passage 111, causing a pressure difference between the front and rear sides of the valve flap 13, pushing the valve flap 13 in the airflow passage. Rotate within 111, change the rotation angle of the valve flap 13 in the airflow passage 111 through the user's exhalation pressure, so as to change the area of the airflow passage 111 blocked by the valve flap 13 along the airflow direction, and then change the airflow flow area in the airflow passage 111 . That is, when the user's exhalation pressure increases, the pressure difference between the front and rear sides of the valve flap 13 increases, the rotation angle of the valve flap 13 in the airflow passage 111 increases, and the area occupied by the valve flap 13 in the airflow passage 111 increases. Larger, resulting in the reduction of the air flow area in the air flow channel 111; when the user's exhalation pressure decreases, the pressure difference between the front and rear sides of the valve flap 13 decreases, and the rotation angle of the valve flap 13 in the air flow channel 111 decreases, and the air flow channel The area occupied by the valve disc 13 in 111 is reduced, resulting in the reduction of the air flow area in the air flow channel 111 . The air flow discharged from the air flow channel 111 to the detection device is controlled by the relationship between the air pressure difference between the front and rear sides of the valve flap 13 in the air flow channel 111 and the air flow flow area, so as to keep the air flow channel 111 flowing out of a constant air flow as much as possible, so that the user can quickly Stable blowout brake flow, improve the reliability of exhaled breath detection.

Moreover, the constant flow valve 1 with adjustable gear position can also be provided with a gear position, and the valve disc 13 is arranged opposite to the gear position. After the user exhales toward the air flow channel 111, the air flow channel 111 is discharged to the air flow of the detection device. The flow is maintained at a constant gear state. Alternatively, the constant flow valve 1 with adjustable gears can also be provided with at least three or more gears, that is, the first valve body 11 is provided with a first gear 112 , a second gear 113 , and a second gear. By moving the first valve body 11, the valve disc 13 can be set correspondingly to one of the gear parts, such as the third gear part, the fourth gear part, etc., so that the air flow channel 111 is in the first gear state or the second gear position. The second gear state, the third gear state, or the Nth gear state, etc., and the air flow rate passing through the airflow channel 111 is different in each gear state. For example, the first gear part 112 corresponds to an airflow rate of 50ml/s±10%, and the second gear part 113 corresponds to an airflow rate of 200ml/s±10%. When the valve disc 13 is set opposite to the first gear part 112, the airflow channel 111 is in the first gear position, and after the user exhales into the airflow channel 111, the air flow rate discharged from the airflow channel 111 to the detection device is maintained at 50ml/s± 10%. When the first valve body 11 is moved, when the valve flap 13 is set opposite to the second gear part 113, the airflow channel 111 is in the second gear position state, and after the user exhales into the airflow channel 111, the airflow channel 111 is discharged to the airflow of the detection device. The flow rate is kept at 200ml/s±10%. In this embodiment, the constant flow valve 1 with adjustable gears can be set with multiple gears to control the flow of multiple gears, and the gear shift can be directly realized in one constant flow valve 1 with adjustable gears, and the operation is simple. convenient.

Further, as shown in FIG. 3 , the constant flow valve 1 with adjustable gear position includes a first elastic member 14, the first elastic member 14 One end is connected with the valve disc 13, and the other end of the first elastic member 14 is connected with the second valve body 12; when the air flow flows through the air flow passage 111, the air flow can overcome the elastic force of the first elastic member 14 to push the valve disc 13 to rotate; the air flow passage 111 has no When the air flow is flowing, the first elastic member 14 drives the valve clack 13 to reset by its resilience force. During the rotation process of the airflow pushing the valve flap 13, the valve flap 13 can overcome the reverse thrust applied by the first elastic member 14 to rotate, and the force of the airflow is balanced with the elastic force of the first elastic member 14; when the airflow disappears, the valve flap 13 The thrust on the first elastic member 14 disappears, and the first elastic member 14 pushes the valve clack 13 back to the initial position by its own resilience, which has a simple structure and reduces the manufacturing cost of the adjustable constant flow valve 1 . When the valve flap 13 is in balance with the first elastic member 14, the angle between the valve flap 13 and the second valve body 12 is not greater than 90°.

Wherein, the first elastic member 14 may be a torsion spring.

The constant flow valve 1 with adjustable gear position also includes a seal, which seals the connection position between the first valve body 11 and the second valve body 12, ensures the airtightness of the air flow channel 111, and reduces the gap between the first valve body 11 and the second valve body 12. There is a gap at the connection position of the valve body 12 , and there is a risk of part of the airflow in the airflow passage 111 leaking along the gap. The sealing member can be a rubber ring, and a sealing ring is placed on the outer ring of the first valve body 11 or the second valve body 12, or sealing oil is set at the connecting position of the first valve body 11 and the second valve body 12, etc. The embodiment does not limit the sealing method.

As shown in FIGS. 1 to 4 , in a possible design, the first valve body 11 is connected to the second valve body 12 along the height direction of the gear-adjustable constant flow valve 1 to form an air flow channel 111 . In this embodiment, the first valve body 11 and the second valve body 12 have a U-shaped structure, and the two are spliced together to form an air flow channel 111 . After the first valve body 11 is spliced with the second valve body 12 , the first valve body 11 can move relative to the second valve body 12 to move the first valve body 11 to realize gear shifting. The first valve body 11 and the second valve body 12 are connected by splicing, which facilitates their assembly. The first valve body 11 and the second valve body 12 can also be connected by other connection methods, which are not limited in this embodiment.

Further, as shown in FIGS. 1 to 4 , the constant flow valve 1 with adjustable gear position also includes a pusher 15, and the constant flow valve 1 with adjustable gear position also includes a pusher 15. When the pusher 15 is pushed, the pusher 15 can drive the first valve body 11 to move. In this embodiment, the pusher 15 and the first valve body 11 can be fixedly connected, and the pusher 15 is pushed, so that the pusher 15 drives the first valve body 11 to move relative to the second valve body 12, thereby realizing the shifting of gears. Wherein, the pushing member 15 and the first valve body 11 can be fixedly connected in the direction of buckle or thread.

Or, the pusher 15 is provided with a slider, and the first valve body 11 is provided with a slideway matched with the slideway, the slider can slide along the slideway, and when the slider moves to abut against the side wall of the slideway, the pusher 15 drives the first valve body 11 to move.

As shown in FIG. 3 and FIG. 4 , the constant flow valve 1 with adjustable gear position includes a housing 16 , the first valve body 11 and the second valve body 12 are installed in the housing 16 , and the first valve body 11 can move relative to the housing 16 ; The constant flow valve 1 with adjustable gear also includes a first limiter 17 and a second limiter 18, the first limiter 17 and the second limiter 18 are mounted on the casing 16, and the first valve body 11 is provided with The first matching part 114 and the second matching part 115; when the first limiting part cooperates with the first matching part 114, the airflow channel 111 is in the first gear state, and when the second limiting part cooperates with the second matching part 115, The airflow channel 111 is in the second gear state.

In this embodiment, the housing 16 is provided with an opening, at least part of the pusher 15 extends out of the housing 16 along the opening, and the pusher 15 can slide along the opening to drive the first valve body 11 to move. The first limiting member 17 and the second limiting member 18 are connected to the inner wall of the casing 16 , and the pushing member 15 is located between the first limiting member 17 and the second limiting member 18 . The first matching portion 114 and the second matching portion 115 are disposed on the outer wall of the first valve body 11 . When the first limiting member 17 cooperates with the first matching portion 114 , the valve disc 13 is opposite to the first gear portion 112 , so that the air flow channel 111 is in the first gear state. Moving the first valve body 11, the first stopper 17 is disengaged from the first matching part 114, and the second stopper 18 is matched with the second matching part 115, and the valve flap 13 is opposite to the second gear part 113, so that Make the airflow channel 111 in the second gear state. Wherein, the first limiting member 17 and The distance between the second limiting parts 18 is smaller than the distance between the first matching portion 114 and the second matching portion 115 . Through the cooperation of the first stopper 17 and the first matching part 114, the cooperation of the second stopper 18 and the second matching part 115 prompts the user to reach the shift position, and restricts the first valve body 11 from continuing to move, ensuring the use When the patient exhales, the airflow channel 111 is always in this gear state, so as to keep the airflow channel 111 flowing out of a constant air flow as much as possible. When shifting gears, the first limiting member 17 can be disengaged from the first matching portion 114 or the second limiting member 18 can be disengaged from the second matching portion 115 only by slightly increasing the driving force to achieve the effect of displacement adjustment.

When the distance between the first fitting part 114 and the second fitting part 115 is long and the stroke of the pusher 15 is required to be greater than the displacement of the pipeline, the length of the slideway can be increased to make the slider slide along the slideway The center is an invalid displacement, when the slider abuts against the side wall of the slideway, the slider pushes the first valve body 11 to move.

Specifically, as shown in Figure 3 and Figure 4, the first limiting member 17 and the second limiting member 18 can be bent elastic pieces, the limiting part of the elastic member is a tapered structure, the first matching part 114 and The second matching portion 115 is a groove. When the first valve body 11 is moved, the side wall of the groove squeezes the elastic piece to make the elastic piece break away from the groove, and the elastic piece is always in a compressed state during the movement of the first valve body 11 . When the other groove moves under the other elastic piece, the elastic piece is partially locked in the groove by its own elastic force.

Or, the first limiting member 17 and the second limiting member 18 are spheres, and the housing 16 has a housing cavity for placing the sphere, the sphere can roll in the housing cavity, and the opening of the housing cavity is smaller than the diameter of the sphere to limit the sphere from falling. The depth of the accommodating cavity is greater than the diameter of the sphere, so that the sphere can shrink into the accommodating cavity. When the first valve body 11 is moved, the ball can be retracted into the accommodating cavity, and when the first stopper 17 (the second stopper 18) cooperates with the first matching part 114 (the second matching part 115), part of the ball falls off. fall into the groove.

As shown in FIG. 5 and FIG. 6 , in another possible design, at least a part of the second valve body 12 is sheathed on the first valve body 11 along the flow direction of the air flow to form an air flow channel 111 . In this embodiment, the first valve body 11 is nested in the second valve body 12 , and by changing the depth at which the first valve body 11 enters the second valve body 12 , gear shifting is realized. Wherein, the first valve body 11 can be a fixed part, and the second valve body 12 can be moved to switch gears, or the second valve body 12 can be a fixed part, and the first valve body 11 can be moved to switch gears, and there is no need to set other The matching part pushes the first valve body 11 or the second valve body 12, which reduces the manufacturing cost.

As shown in Figure 5 and Figure 6, further, the constant flow valve 1 with adjustable gear also includes a third stopper 19, the third stopper 19 is connected with the second valve body 12, the first valve body 11 is set There are a third matching part 116 and a fourth matching part 117; when the third limiting part 19 cooperates with the third matching part 116, the airflow channel 111 is in the first gear state, and the third limiting part 19 and the fourth matching part 117 When mated, the airflow channel 111 is in the second gear state.

In this embodiment, the third matching portion 116 and the fourth matching portion 117 are disposed on the outer wall of the first valve body 11 . When the third limiting member 19 cooperates with the third matching portion 116 , the valve disc 13 is opposite to the first gear portion 112 , so that the air flow channel 111 is in the first gear state. Moving the first valve body 11, the third stopper 19 is disengaged from the third fitting part 116, and the third stopper 19 is moved to the fourth fitting part 117 along with the first valve body 11, so that the third stopper 19 and The fourth matching part 117 is matched, and the valve flap 13 is opposite to the second gear part 113 , so that the air flow channel 111 is in the second gear state. Through the cooperation of the third stopper 19 and the third matching part 116, the cooperation of the third stopper 19 and the fourth matching part 117 prompts the user to reach the shift position, and restricts the first valve body 11 from continuing to move, ensuring the use When the patient exhales, the airflow channel 111 is always in this gear state, so as to keep the airflow channel 111 flowing out of a constant air flow as much as possible. When shifting gears, the third limiting member 19 can be disengaged from the third matching portion 116 or the fourth matching portion 117 only by slightly increasing the driving force.

Specifically, as shown in Figure 5 and Figure 6, the second valve body 12 is provided with a receiving groove 121, and the third stopper 19 is arranged in the receiving groove 121. in the receiving groove 121; during the movement of the first valve body 11, the third limiting member 19 shrinks into the receiving groove 121; At least a part of the position member 19 is engaged with the third matching portion 116 or the fourth matching portion 117 . In this embodiment, when the first valve body 11 needs to be shifted (such as shifting from the first gear state to the second gear state) to move the first valve body 11, the side wall of the third fitting part 116 pushes the third stopper 19 out and shrinks to In the accommodating groove 121, during the movement of the first valve body 11, the third stopper 19 abuts against the outer wall of the first valve body 11 and shrinks into the accommodating groove 121 all the time. When the limiting member 19 is below, the third limiting member 19 falls and is locked on the fourth matching portion 117 . By setting the accommodating groove 121, when the third limiting member 19 is not clamped on the third fitting portion 116 or the fourth fitting portion 117, it is set in the accommodating groove 121, thus there is no need to provide movement for the third limiting member 19 space, reducing the overall volume of the constant flow valve 1 with adjustable gears, which is convenient for storage.

Wherein, the third limiting member 19 may include a limiting block and a spring, one end of the spring is connected to the bottom wall of the receiving groove 121, the other end of the spring is connected to the limiting block, the third matching portion 116 and the fourth matching portion 117 are groove. When the first valve body 11 is moved, the side wall of the groove pushes the limit block out of the groove, and at the same time the limit block presses the spring. When the other groove moves below the limit block, the limit block does not press against the spring, and the spring pushes the limit block into the groove by its resilience.

Or the third stopper 19 is a sphere, the sphere can roll in the receiving groove 121, the opening of the accommodating groove 121 is smaller than the diameter of the sphere, to limit the sphere from falling, and the depth of the accommodating groove 121 is greater than the diameter of the sphere, so that the sphere can Shrink into the receiving groove 121. When the first valve body 11 is moved, the ball can be retracted into the receiving groove 121 , and when the third limiting portion cooperates with the third matching portion 116 (fourth matching portion 117 ), part of the ball falls into the groove.

In a possible design, the first gear part 112 includes a first curved surface, and the distance from the first curved surface to the valve disc 13 gradually increases from the air inlet 111a to the air outlet 111b, and the valve disc 13 corresponds to the first curved surface. During the rotation of a curved surface, the flow rate of the first airflow in the airflow channel 111 remains unchanged. The second gear part 113 includes a second curved surface. From the air inlet 111a to the air outlet 111b, the distance between the second curved surface and the valve flap 13 gradually decreases, and the valve flap 13 rotates corresponding to the second curved surface. The flow rate of the second airflow in 111 remains unchanged. The first curved surface is connected to the near end of the second curved surface, and the first curved surface is closer to the valve disc 111 relative to the second curved surface.

In this embodiment, from the air inlet 111a to the air outlet 111b, the slope of the first curved surface gradually decreases, through the change of the curvature of the first curved surface, to match the angle change during the rotation of the valve disc 13, and the air flow channel The airflow area capable of circulating the airflow in the airflow channel 111 is to ensure a constant airflow out of the airflow channel 111 as much as possible. From the air inlet 111a to the air outlet 111b, the slope of the second curved surface gradually increases, through the change of the curvature of the second curved surface, to match the angle change during the rotation of the valve disc 13, and to allow airflow to flow through the airflow channel 111 The airflow area of the airflow channel 111 is guaranteed to flow out of a constant airflow as much as possible.

Further, as shown in Figure 2 and Figure 7,

According to the formula (where Q is the flow rate, C is the throttling coefficient, A is the flow area,

ΔP is the pressure difference between the front and back sides of the disc 13, and ρ is the fluid density. ) shows that at the air inlet 111a, as the air flow velocity increases, the pressure difference ΔP on both sides of the valve disc 13 increases/decreases, the rotation angle of the valve disc 13 increases/decreases, and the distance between the free end 131 and the first gear The distance of the portion 112 is reduced/increased, resulting in a decrease/increase of the flow area A in the airflow passage 111, thereby maintaining the air flow Q flowing through the airflow passage 111 when the airflow passage 111 is in the first gear state. As the air flow velocity decreases, the pressure difference ΔP on both sides of the valve disc 13 increases/decreases, the rotation angle of the valve disc 13 increases/decreases, the distance between the free end 131 and the second gear part 113 decreases/increases, Cause the flow area A in the airflow channel 111 to decrease/increase, thereby keeping the airflow channel 111 in the second gear state The flow rate Q of the air flow that circulates at that time. Furthermore, the curvature change law of the first curved surface of the first gear part 112 and the second curved surface of the second gear part 113 conforms to Formula 1 and Formula 2:

Note: Formula 1 can be obtained according to A=LH-Bsin(θ(P))(L-2d)

Note: Formula 2 can be based on get

In the formula, Q is the flow rate, C is the throttling coefficient, A is the flow area, ΔP is the pressure difference between the front and rear sides of the disc 13, ρ is the fluid density, L is the width of the airflow channel 111, and d is the side wall of the valve disc 13 and the airflow channel 111 The spacing, H is the height of the airflow channel 111, B is the length of the valve disc 13, θ is the rotation angle of the valve disc 13, which is related to ΔP. Wherein, θ is the angle at which the pressure difference pushes the disc 13 to balance with the first elastic member 14 , and the stiffness of the first elastic member 14 is simulated to fit the height H of the airflow channel 111 .

In a possible design, the constant flow valve with adjustable gear can also be used for pipeline gas output or water output, such as in natural gas pipelines or water pipelines, so that it can flow out constant fluid under different pressures.

As shown in Figure 8, this embodiment also provides a detection device 2 for detecting the content of nitric oxide. The detection device 2 includes: a constant flow valve 1 with adjustable gears, and a constant flow valve 1 with adjustable gears It is the constant flow valve 1 with adjustable gear position in the above-mentioned embodiments; the detection device 21 is used to detect the gas (such as nitric oxide gas) passing through the constant flow valve 1 with adjustable gear position, so as to Diagnose disease.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims (13)

1. A constant flow valve with adjustable gear position, characterized in that the constant flow valve with adjustable gear position includes:

   A first valve body; the first valve body has an inner wall, and the inner wall is provided with a first gear part and a second gear part;

   a second valve body, the first valve body cooperates with the second valve body to form an airflow passage, and the first valve body can move relative to the second valve body;

   Valve clack, the valve clack is arranged in the air flow passage, the valve clack is provided with a free end and a fixed end, and the free end can rotate around the fixed end; the air flow passage is provided with an air inlet and an air outlet , from the air inlet to the air outlet, as the pressure difference on both sides of the valve flap gradually increases, the rotation angle of the valve flap increases, and the free end and the first gear position The distance between the parts or the second gear part gradually decreases;

   Wherein, by moving the first valve body, the valve disc can be arranged opposite to the first gear part or the second gear part, so that the air flow channel is in the first gear state or the second gear state. In the gear state, the first airflow flow rate passing through the airflow passage in the first gear state is different from the second airflow flow rate that can pass through the airflow passage in the second gear state.
2. The constant flow valve with adjustable gear position according to claim 1, wherein the first gear position part comprises a first curved surface, and the direction from the air inlet to the air outlet, the first The distance between the curved surface and the valve flap gradually increases, and the first air flow in the airflow channel remains unchanged during the rotation of the valve flap corresponding to the first curved surface;

   The second gear part includes a second curved surface, and the distance from the second curved surface to the valve flap gradually decreases from the air inlet to the air outlet, and the valve flap corresponds to the During the rotation process of the second curved surface, the flow rate of the second airflow in the airflow channel remains unchanged;

   The first curved surface is connected to the near end of the second curved surface, and the first curved surface is closer to the valve disc relative to the second curved surface.
3. According to the constant flow valve with adjustable gears according to claim 2, it is characterized in that, the curvature change law of the first curved surface and the second curved surface conforms to Formula 1 and Formula 2:
   
   

   In the formula, Q is the flow rate, C is the throttling coefficient, A is the flow area, ΔP is the pressure difference between the front and rear sides of the valve disc, ρ is the fluid density, L is the width of the air flow channel, d is the distance between the valve disc and the side wall of the air flow channel, and H is The height of the air flow channel, B is the length of the disc, and θ is the rotation angle of the disc.
4. The constant flow valve with adjustable gear according to any one of claims 1-3, wherein the first valve body further comprises one or more gears.
5. The constant flow valve with adjustable gear according to any one of claims 1-4, characterized in that, the constant flow valve with adjustable gear includes a first elastic member, and one end of the first elastic member connected with the valve clack, and the other end of the first elastic member is connected with the second valve body;

   When the airflow flows through the airflow channel, the airflow can overcome the elastic force of the first elastic member to push the valve clack to rotate;

   When there is no airflow in the airflow channel, the first elastic member drives the valve clack to reset by its resilience force.
6. The constant flow valve with adjustable gear position according to any one of claims 1 to 5, characterized in that, the constant flow valve with adjustable gear position further comprises a seal, and the seal seals the first The valve body is connected to the second valve body.
7. The constant flow valve with adjustable gear according to any one of claims 1-6, characterized in that, along the height direction of the constant flow valve with adjustable gear, the first valve body and the second The two valve bodies are connected to form the air flow channel.
8. The constant flow valve with adjustable gear according to claim 7, characterized in that, the constant flow valve with adjustable gear further includes a pusher, and the constant flow valve with adjustable gear further includes a pusher, When the pusher is pushed, the pusher can drive the first valve body to move.
9. The constant flow valve with adjustable gear according to claim 7, characterized in that, the constant flow valve with adjustable gear includes a casing, and the first valve body and the second valve body are installed on the In the casing, the first valve body can move relative to the casing;

   The constant flow valve with adjustable gear also includes a first limiter and a second limiter, the first limiter and the second limiter are installed on the housing, and the first valve The body is provided with a first matching portion and a second matching portion;

   When the first limiting part cooperates with the first matching part, the air flow channel is in the first gear state; when the second limiting part cooperates with the second matching part, the airflow channel The channel is in the second gear state.
10. The constant flow valve with adjustable gear according to any one of claims 1 to 3, characterized in that, along the flow direction of the air flow, at least part of the second valve body is sleeved on the first valve body to form a the airflow channel.
11. The constant flow valve with adjustable gear position according to claim 10, characterized in that, the constant flow valve with adjustable gear position further comprises a third limiter, and the third limiter is connected to the second limiter. The valve body is connected, and the first valve body is provided with a third matching part and a fourth matching part;

    When the third limiting member cooperates with the third matching portion, the airflow channel is in the first gear state, and when the third limiting member cooperates with the fourth matching portion, the airflow passage The channel is in the second gear state.
12. The constant flow valve with adjustable gear according to claim 11, wherein the second valve body is provided with a receiving groove, and the third limiting member is arranged in the receiving groove;

    During the movement of the first valve body, the third limiting member shrinks into the receiving groove;

    When the airflow channel is in the first gear state or the second gear state, at least a part of the third limiting member is engaged with the third matching portion or the fourth matching portion.
13. A detection device, characterized in that the detection device comprises:

    A constant flow valve with adjustable gear, the constant flow valve is the constant flow valve with adjustable gear according to any one of claims 1-12;

    A detection device, the detection device is used to detect the gas passing through the constant flow valve.