CN114810668A

CN114810668A - Turbine and breathing machine

Info

Publication number: CN114810668A
Application number: CN202210268011.2A
Authority: CN
Inventors: 罗磊; 杜巍; 罗千千
Original assignee: Harbin Institute of Technology
Current assignee: Harbin Institute of Technology
Priority date: 2022-03-17
Filing date: 2022-03-17
Publication date: 2022-07-29

Abstract

The invention discloses a turbine and a breathing machine, wherein the turbine comprises a volute and an impeller; the volute comprises a spiral volute chamber, and the spiral volute chamber is provided with an annular gas inlet; the impeller includes rim plate body and a plurality of blade, and the rim plate body includes the chassis and follows the shaft hole that the chassis central line set up, the edge of the gaseous entry of periphery butt on chassis, and a plurality of blades are radial distribution and locate the chassis, and the blade includes leading edge portion and trailing edge portion, and the leading edge portion sets up towards the edge extension of chassis along the periphery in shaft hole, and the trailing edge portion is connected in the periphery on chassis, and the tip of trailing edge portion sets up towards gaseous entry, and the height of trailing edge portion is unanimous with the width of gaseous entry. According to the technical scheme, the diffusion section is omitted, so that the size of the turbine is reduced, and the noise and the production cost are reduced.

Description

Turbine and breathing machine

Technical Field

The invention relates to the technical field of medical instruments, in particular to a turbine and a breathing machine.

Background

In modern clinical medicine, a ventilator is used for respiratory failure caused by various reasons, anesthesia respiratory management during major operations, respiratory support therapy and emergency resuscitation as an effective means capable of providing energy through the outside to replace self-ventilation of a human body, and occupies a very important position in the modern medical field.

The key part of the breathing machine is a turbine, the turbine comprises a volute and an impeller, the impeller is driven by a motor shaft, gas is sucked from an inlet under the action of the impeller, acts through the impeller to obtain kinetic energy and boost pressure, and then is further converted into required high-pressure gas through a flow passage of the volute. The existing breathing machine turbine needs to be provided with a diffusion section at an impeller gas outlet and a volute gas inlet because the pressure rise of gas passing through an impeller is insufficient, and is used for the pressure rise of the gas.

Disclosure of Invention

The main object of the present invention is to propose a turbine aimed at reducing the volume of the turbine.

To achieve the above object, the present invention provides a turbine comprising:

a volute comprising a spiral volute chamber provided with an annular gas inlet; and

the impeller, the impeller includes rim plate body and a plurality of blade, the rim plate body includes the chassis and follows the shaft hole that the chassis central line set up, the periphery butt on chassis the edge of gas inlet, it is a plurality of the blade is radially distributed and locates the chassis, the blade includes leading edge portion and trailing edge portion, the leading edge portion is followed the periphery in shaft hole is towards the edge extension setting of chassis, trailing edge portion connect in the periphery on chassis, the trailing edge portion orientation gas inlet sets up, the height of trailing edge portion with gas inlet's width is unanimous.

Optionally, a side surface of the blade away from the base plate is a blade tip, and a contour line of the front edge part is a straight line.

Optionally, the trailing edge portion is a plane, and the plane is arranged in parallel with a center line of the chassis.

Optionally, two opposite surfaces of the blade are a suction surface and a pressure surface, respectively, the impeller rotates clockwise, the suction surface protrudes towards the rotation direction to form a curved surface, and the pressure surface sinks towards the rotation direction to form a curved surface.

Optionally, the spiral volute is circular in transverse cross-section;

and/or the cross section of the spiral vortex chamber in the anticlockwise direction is in a growing trend.

Optionally, the surface of one side of the blade, which is far away from the chassis, is a blade tip, and a first circle is formed by taking the distance from the intersection point of the contour line of the front edge part and the blade tip to the center line of the chassis as a radius, and the diameter of the first circle ranges from 10mm to 20 mm;

and/or the surface of one side of the blade close to the chassis is a blade root, a second circle is formed by taking the distance from the intersection point of the contour line of the front edge part and the blade root to the central line of the chassis as a radius, and the diameter range of the second circle is 3mm to 5 mm.

Optionally, the volute further comprises a diffuser connected to the tail of the spiral volute, and the transverse cross section of the diffuser is circular.

Optionally, the length of the diffuser pipe ranges from 33mm to 34 mm;

and/or the cross section of the diffuser pipe increases from one end connected with the tail part of the spiral volute to the other end.

Optionally, the volute further comprises a volute tongue, and the upper edge and the lower edge of the volute tongue are on the same vertical curved surface.

The invention further provides a breathing machine which comprises the turbine and the motor, wherein the rotating shaft of the motor is inserted into the shaft hole.

According to the technical scheme, the impeller is adopted to meet the regulation of the gas boosting of the turbine, the arrangement of the diffusion section is omitted, the chassis of the impeller can be directly connected with the spiral volute chamber, the height of the tail edge part of the blade is consistent with the width of the gas inlet, the boosting gas generated by the impeller can directly enter the volute chamber, the size of the turbine is reduced due to the elimination of the diffusion section, and the noise and the production cost are reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural view of a turbine according to an embodiment of the present invention;

FIG. 2 is a schematic view of another aspect of the turbine according to the present invention;

FIG. 3 is an enlarged view of a portion of FIG. 2 at A;

FIG. 4 is a top view of an embodiment of a turbine of the present invention;

FIG. 5 is a top view of an impeller of the turbine shown in FIG. 1;

FIG. 6 is a schematic illustration of the construction of the impeller of the turbine shown in FIG. 1;

FIG. 7 is a schematic view of the structure of the impeller in the turbine of the present invention in the direction of contact with the gas flow;

FIG. 8 is a sectional view of an embodiment of a turbine of the present invention;

FIG. 9 is a schematic view of a radial subdivision of the volute and a partial enlargement at the volute tongue in a turbine according to the present invention;

FIG. 10 is a schematic view of a radial subdivision of a volute without a volute tongue in a turbine according to the present invention;

FIG. 11 is a schematic circumferential subdivision of the volute chamber of the turbine of the present invention;

FIG. 12 is a schematic circumferential subdivision of a volute diffuser in a turbine according to the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				1	Turbine wheel	10	Spiral casing
11	Spiral volute chamber	13	Gas inlet
				15	Diffusion tube	17	Vortex tongue
30	Impeller wheel	31	Wheel disc body
				311	Chassis	313	Shaft hole
33	Blade	331	Front edge part
				333	Trailing edge part	335	Suction surface
337	Pressure surface

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between the embodiments may be combined with each other, but must be based on the realization of the technical solutions by a person skilled in the art, and when the technical solutions are contradictory to each other or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The invention proposes a turbine 1.

In the embodiment of the present invention, as shown in fig. 1 to 6, the turbine 1 includes a volute 10 and an impeller 30; the volute 10 comprises a spiral volute chamber 11, and the spiral volute chamber 11 is provided with an annular gas inlet 13; the impeller 30 includes a disk body 31 and a plurality of blades 33, the disk body 31 includes a chassis 311 and a shaft hole 313 arranged along the center line of the chassis 311, the periphery of the chassis 311 abuts against the edge of the gas inlet 13, the plurality of blades 33 are radially distributed on the chassis 311, the blades 33 include a front edge portion 331 and a tail edge portion 333, the front edge portion 331 extends along the periphery of the shaft hole 313 toward the edge of the chassis 311, the tail edge portion 333 is connected to the periphery of the chassis 311, the tail edge portion 333 is arranged toward the gas inlet 13, and the height of the tail edge portion 333 is consistent with the width of the gas inlet 13.

The micro turbine 1 operates in the following manner: the turbine 1 communicates with a motor, a rotation shaft of the motor is connected to a shaft hole 313 provided in the impeller 30, and the rotation of the rotation shaft rotates the impeller 30. When the outside air enters the turbine 1, the outside air is conveyed towards the impeller 30 from a direction perpendicular to the base plate 311, the air is conveyed to the impeller 30, and firstly contacts with the front edge portion 331, the impeller 30 is driven by the motor to rotate, the air flows to the tail edge portion 333 along the blades 33, the tail edge portion 333 applies work to the air, because the total pressure and the static pressure of the air flow of the tail edge portion 333 are higher than those of the front edge portion 331, when the air flow flows to the tail edge portion 333 from the front edge portion 331, the blades 33 play a role of increasing the kinetic energy and the pressure of the air flow, and further the pressure of the air flow is increased; the gas flow is boosted by the work of the impeller 30 and flows to the gas inlet 13, then passes through the spiral volute chamber 11, the section area of the spiral volute chamber 11 is gradually increased, the gas flow passes through the gradually increased spiral volute chamber 11, the gas speed is reduced, the pressure is increased, the kinetic energy is converted into pressure energy, and the gas flows out from the outlet of the volute 10 after double boosting.

The periphery of the chassis 311 is abutted against the edge of the gas inlet 13, the tail edge part 333 is connected with the periphery of the chassis 311, the height of the tail edge part 333 is consistent with the width of the gas inlet 13, and then gas can directly flow from the front edge part 331 to the tail edge part 333 to do work and enter the spiral volute 11 after being boosted, so that the requirement of boosting the gas flow is met, the arrangement of a diffusion section can be cancelled, and the gas flow is not required to be further boosted by the diffusion section; the elimination of the diffuser section enables the periphery of the base plate 311 to be directly abutted against the volute 10, so that the volume of the spiral volute chamber 11 is reduced, the step of utilizing the diffuser section to boost the gas is solved, the noise generated during the working of the diffuser section is reduced, and the noise is reduced. The height of the trailing edge part 333 is consistent with the width of the gas inlet 13, so that gas can directly enter the gas inlet 13 when flowing through the trailing edge part 333 and flowing out of the impeller 30, the impact and the slowing of the gas are reduced, the flowing effect of the gas flow is improved, and the boosting effect of the gas is kept.

Further, as shown in fig. 8, the outlet width b of the impeller 30, i.e., the height of the trailing edge part 333 of the vane 33, can be adjusted according to the required inlet flow rate and flow velocity, and in this embodiment, the outlet width b is 3 mm. The width b3 of the gas inlet 13 can be calculated according to the formula, in the formula, b is the outlet width of the impeller 30, that is, the height of the tail part 333 of the blade 33, S is the cover plate thickness of the impeller 30, C is a constant, generally, C is 5-20 mm, and optionally, the value of C is selected according to specific situations. The specific rotating speed is lower, and the impeller is used for 30 hours, and a small value is taken; otherwise, it takes a large value, and thus in the present embodiment, the width b3 of the gas inlet 13 is 3mm, and further the height of the trailing edge portion 333 coincides with the width of the gas inlet 13.

Further, as shown in fig. 5, the number of the blades 33 is plural, and it is preferable that the number of the blades 33 of the impeller 30 is 8 to 15 by calculation. In this embodiment, the number of the blades 33 is 15, and the blades 33 are set to 15, so that enough blades 33 can work on the gas flow when the impeller 30 rotates, and the pressure increase requirement of the impeller 30 on the gas is met. It will be appreciated that the required strength of the vanes 33, the size and number of the impellers 30 affect the thickness selection of the vanes 33, and when the number of vanes 33 is 15, the thickness d of the vanes 33 is preferably 0.5mm to 1 mm.

Further, the thickness of the chassis 311 determines the strength of the chassis 311, in this embodiment, the thickness of the chassis 311 is 0.4mm to 0.8mm, and the thickness of the chassis 311 is 0.4mm to 0.8mm, so that on one hand, the strength of the chassis 311 can be ensured, the chassis can still maintain a good shape in a high-strength working state, the service life of the turbine 1 is prolonged, on the other hand, insufficient strength of the chassis 311 caused by too small thickness can be avoided, and the increase of the volume of the impeller 30 caused by too large thickness can be avoided, further the volume of the turbine 1 is increased, and the reasonable volume distribution of the turbine 1 is realized.

According to the technical scheme, the impeller 30 is adopted to meet the regulation of the gas boosting of the turbine 1, the arrangement of a diffusion section is omitted, the base plate 311 of the impeller 30 can be directly connected with the spiral volute 11, the height of the tail edge part 333 of the blade 33 is consistent with the width of the gas inlet 13, the boosting gas generated by the impeller 30 can directly enter the volute, the size of the turbine 1 is reduced due to the elimination of the diffusion section, and the noise and the production cost are reduced.

In an embodiment of the present invention, as shown in fig. 1 to 7, the contour line of the front edge portion 331 is a straight line.

The contour line of the front edge part 331 is a straight line, the front edge part 331 of the blade 33 is a connecting line between the blade top and the shaft hole 313, and the front edge part 331 with the straight contour line can make the inlet airflow passing through the front edge part 331 more uniform, increase the stability of the impeller 30, improve the stability margin, reduce the impact of the front edge part 331 on the airflow and improve the stability of the input airflow into the impeller 30.

Further, as shown in fig. 5 to 7, the inlet airflow direction at the blade root of the leading edge portion 331 has an angle β 1h with the tangent line of the blade root circle of the leading edge portion 331 at the leading edge blade root, the inlet airflow direction at the blade tip of the leading edge portion 331 has an angle β 1s with the tangent line of the blade tip circle of the leading edge portion 331 at the leading edge blade tip, and the outlet airflow direction at the trailing edge portion 333 has an angle β 2 with the tangent line of the blade tip circle of the trailing edge portion 333 at the trailing edge. The flow direction of the airflow and the profile of the blade 33 can be determined by β 1h, β 1s, and β 2, and since the blade 33 applies work to the airflow and the blade 33 receives the reaction force of the airflow, the blade 33 may not meet the strength requirement if it is too bent, optionally, the range of β 1h is not more than 50 °, the range of β 2 is not less than 75 °, and β 1s can be determined by the specific values of β 1h and β 2 and the specific shape of the leading edge of the blade 33, where the specific values of β 1h and β 2 are not listed one by one.

In one embodiment of the present invention, as shown in fig. 6 and 7, the trailing edge 333 is a plane, and the plane is parallel to the center line of the chassis.

The tail edge part 333 is of a plane structure, and the plane is parallel to the central line of the base plate 311, so that the tail edge part 333 can be ensured to be parallel to the gas inlet 13, on one hand, the tail edge part 333 is ensured not to be in contact with the gas inlet 13, the stability and independence of the operation of the impeller 30 and the volute 10 are ensured, on the other hand, the connectivity of the tail edge part 333 and the gas inlet 13 is maintained, gas can be ensured to flow from the impeller 30 to the gas inlet 13 and enter the spiral volute chamber 11, and the projections of the upper end part and the lower end part of the tail edge part 333, which are positioned on the base plate 311, are not overlapped, the rotation angle of the blade 33 is increased, and the boosting effect is improved.

In an embodiment of the present invention, as shown in fig. 6, the two opposite surfaces of the vane 33 are a suction surface 335 and a pressure surface 337, respectively, the impeller 30 rotates in a clockwise direction, the suction surface 335 is convex toward the rotation direction to form a curved surface, and the pressure surface 337 is concave toward the rotation direction to form a curved surface.

The suction surface 335 and the pressure surface 337 of the blade 33 are two opposite surfaces between the blade tip and the blade root, the suction surface 335 and the pressure surface 337 are connected to the upper surface of the base plate 311 along the molded line direction of the blade 33, and the intersection line of the trailing edge 333 and the suction surface 335 and the pressure surface 337 has a rounded corner. It will be appreciated that the suction side 335 of one blade 33 is opposite the pressure side 337 of another blade 33, the suction side 335 may be used to increase the suction of the blade 33 to the gas so that the gas flow may quickly enter the impeller 30, and the pressure side 337 may be used to increase the work done by the blade 33 to the gas so that the gas is pressurized and the gas pressure is increased.

In one embodiment of the present invention, as shown in fig. 11, the spiral volute 11 has a circular transverse cross-section;

and/or the cross section of the spiral volute 11 in the anticlockwise direction is in a growing trend.

The spiral line of the spiral volute 11 is formed by using the Pleiderer theory based on the speed, the transverse section of the spiral volute 11 is circular, and the spiral volute 11 is formed by sweeping the spiral line and the circular formed at the corresponding position and the gas inlet 13. Thus, the radial dimension of the outer wall of the volute increases progressively along the direction of gas flow in the volute, the increasing proportion being formed by the velocity-based Pleiderer theory, as a function of the flow rate of the centrifugal compressor and the proportional relationship of the sections. So set up, can satisfy the air current and reach the effect that steps up when passing through spiral volute 11, satisfy gaseous demand that steps up.

In an embodiment of the present invention, as shown in fig. 1 to 8, a surface of the blade 33 away from the bottom plate 311 is a blade tip, and a first circle is formed by taking a distance from an intersection point of a contour line of the front edge portion 331 and the blade tip to a center line of the bottom plate 311 as a radius, and a diameter of the first circle ranges from 10mm to 20 mm;

and/or, the surface of the blade 33 close to the chassis 311 is a blade root, and a second circle is formed by taking the distance from the contour line of the front edge part 331 to the intersection point of the blade root and the central line of the chassis 311 as a radius, and the diameter of the second circle ranges from 3mm to 5 mm.

As shown in fig. 8, in accordance with the required inlet flow rate and flow velocity, and in order to satisfy the requirement of small portable volume, a first circle is formed with a radius of the distance from the intersection point of the contour line of the leading edge portion 331 and the tip of the blade to the center line of the base plate 311, the diameter of the first circle is D1, preferably, the range of D1 is 10mm to 20 mm; a second circle is formed by taking the distance from the contour line of the front edge part 331 to the intersection point of the blade root and the blade root as a radius, the diameter of the second circle is D0, and preferably, the range of D0 is 3 mm-5 mm.

Further, as shown in fig. 8, the diameter of a circle formed by using the distance from the trailing edge 333 to the center line of the base 311 as a radius is D2, the range of D2 is 24mm to 50mm, and D2 determines the radial dimension of the centrifugal impeller 30.

In an embodiment of the present invention, as shown in fig. 12, a diffuser 15 is connected to the rear portion of the spiral scroll 11, and the diffuser 15 has a circular transverse cross-section.

The discharge port equivalent diameter Dd, which is the outlet diameter of the spiral volute 11, can be selected according to the design of the impeller 30. In the embodiment of the present invention, the equivalent diameter Dd of the discharge port ranges from 14mm to 16mm, and specific values of Dd are not listed.

In one embodiment of the present invention, as shown in FIG. 10, the length of the diffuser 15 ranges from 33mm to 34 mm;

and/or the cross section of the diffuser 15 increases from one end connected with the tail part of the spiral volute 11 to the other end.

The height L of the diffusion pipe 15 is measured to be a small value to reduce the size of the air compressor under the condition of ensuring the diffusion angle and the installation requirement, the range of the height L of the diffusion pipe 15 is 33 mm-34 mm, and the specific values of L are not listed.

Further, the transverse section of the diffusion pipe 15 is circular, so that the effect of boosting when the air flow passes through the spiral vortex chamber 11 can be achieved, and the boosting requirement of the gas can be met.

In an embodiment of the present invention, as shown in fig. 1 to 4, the volute casing 10 further includes a volute tongue 17, and an upper edge and a lower edge of the volute tongue 17 are on the same vertical curved surface.

The upper edge and the lower edge of the vortex tongue 17 are on the same vertical curved surface, that is, the radial offset of the vortex tongue 17 is 0, according to experimental data, the smaller the radial offset of the vortex tongue 17 is, the higher the efficiency of the micro-turbine 1 is, and when the radial offset is 0, the highest efficiency is obtained. When the radial offset is 0, the offset of the vortex tongue 17 is reduced to reduce the obstruction to the airflow channel, so that the impact of the airflow on the vortex tongue 17 is small, the pulsation can be reduced, and the service life of the micro turbine 1 is prolonged.

Further, as shown in FIG. 10, the vortex tongue 17 has a spiral angle α ₀ The included angle between the tangent of the spiral line and the tangent of the base circle at the initial point of the spiral line of the vortex chamber. To allow the gas to pass from the impeller 30 into the volute without impingement, α is optionally generally selected ₀ The angle of the flow, equal to the absolute velocity of the impeller 30 just after its exit, is 3.14 ° for the pitch angle α 0 of the volute tongue 17 in the schematic representation of the invention.

Further, as shown in fig. 9, the setting angle of the volute tongue 17 is phi 0, and theoretically, the volute tongue 17 should be on the base circle D3 of the starting point of the volute spiral, but this will make the gap between the volute tongue 17 and the impeller 30 too small, easily generating vibration and noise, and the volute tongue 17 too thin, so the volute tongue 17 is generally moved phi 0 along the volute spiral. Optionally, the setting angle of the vortex tongue 17 is selected according to the specific rotation speed. The radius r3 of the vortex tongue 17 is determined by the rotation angle phi 0 of the vortex tongue 17 and the setting angle phi 0 of the vortex tongue 17 of the vortex chamber and the relevant parameters of the diffuser 15, and the setting angle phi 0 of the vortex tongue 17 of the vortex chamber is 32.9 degrees in the schematic view of the present invention.

The invention further provides a respirator, which comprises a turbine 1 and a motor, wherein a rotating shaft of the motor is inserted in the shaft hole 313, the specific structure of the turbine 1 refers to the above embodiments, and the respirator adopts all technical solutions of all the above embodiments, so that all beneficial effects brought by the technical solutions of the above embodiments are at least achieved, and details are not repeated herein.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A turbine for a ventilator, the turbine comprising:

2. The turbine of claim 1, wherein the contour of the leading edge portion is a straight line.

3. The turbine of claim 2, wherein the trailing edge portion is a plane disposed parallel to a centerline of the chassis.

4. The turbine of claim 2, wherein the opposite surfaces of the blade are a suction surface and a pressure surface, respectively, and the impeller rotates in a clockwise direction, the suction surface is convex toward the rotation direction to form a curved surface, and the pressure surface is concave toward the rotation direction to form a curved surface.

5. The turbine of claim 1, wherein the spiral volute is circular in transverse cross-section;

6. The turbine of claim 2, wherein a side surface of the blade away from the base plate is a blade tip, and a first circle having a diameter in a range of 10mm to 20mm is formed by taking a distance from an intersection point of a contour line of the leading edge portion and the blade tip to a center line of the base plate as a radius;

7. The turbine of claim 1, wherein the volute further comprises a diffuser connected to an aft portion of the spiral volute, the diffuser having a circular transverse cross-section.

8. The turbine of claim 7, wherein the diffuser has a length in the range of 33mm to 34 mm;

9. The turbine of claim 1, wherein the volute further comprises a volute tongue, wherein an upper edge and a lower edge of the volute tongue are on the same vertical curved surface.

10. A ventilator comprising the turbine according to any one of claims 1 to 9 and a motor having a rotating shaft inserted into the shaft hole.