BLOWER FOR RESPIRATOR DEVICE

Abstract

A pressurized treatment gas supply device has a lower enclosure and an upper enclosure. The air outlet is formed by part of the upper enclosure and lower enclosure and the gas outlet direction is tangent to the outer surface of the enclosure. The lower enclosure is has an annular wall A and an outer wall. The space between the outer wall and the upper enclosure wall forms a gas path leading to the gas outlet. A motor is located on the inner side of the lower enclosure. The output shaft end of motor is arranged on the lower enclosure and output shaft of the motor is connected to an impeller. An gas inlet structural member is arranged on the lower enclosure, the end that opposite to impeller is axial air inlet end. The noise silencing chamber is formed between the top of air inlet structural member and the annular frame.

Claims

1. A blower for respirator device, comprising: motor (2), impeller (3), lower enclosure (4), upper enclosure (5) and air inlet structure (6), among them, lower enclosure (4) is assembled to the upper enclosure (5), the air outlet (13) is formed by part of the upper enclosure and lower enclosure (5,4); The end of lower enclosure (4) is open, top of it has a annular frame (404), the motor (2) is located on the inner side of the lower enclosure (4), the output shaft end is arranged on the lower enclosure (4). Output shaft (206) of the motor (2) is connected to an impeller (3), which is positioned between the annular frame (404) and a top plate (504) of upper enclosure (5); The air inlet structural member (6) arranged on the lower enclosure (4), its end opposite to impeller (3) is axial air inlet end, the noise silencing chamber (8) is formed between the top of air inlet structural member (6) and the annular frame (404), when the motor (2) driving impeller (3), the external cold air flows through air inlet structural member (6), and enters into the noise silencing chamber (8) along the axial direction of the enclosure, then flows through the surface of motor (2) for heat exchange, the gas after heat exchange flows out through the described air outlet (13).

2. The blower according to the claim 1, wherein the air inlet structural member (6) includes flat plate (601) and air inlet tube (602), the flat plat is annular type, which mounted on the lower enclosure (4), there are many inlet hole B(604) along with circumferential direction on the flat plate (601). The bottom of the inlet tube (602) connected to inlet hole B(604) and top of it with annular frame (404) formed noise silencing chamber (8).

3. The blower according to the claim 2, wherein the flat plate (601) has drainage holes (603) arranged.

4. The blower according to the claim 2, wherein the flat plat (601) has a motor support ring (7), this motor support ring (7) and flat plate (601) work together as motor (2) supporting structure of motor's non-output shaft end.

5. A blower for respirator device comprising: motor (2), impeller (3), lower enclosure (4), upper enclosure (5) and sound absorbing foam (11). Among them, lower enclosure (4) is connected to an upper enclosure (5), air outlet (13) are formed by part of the upper enclosure and lower enclosure (5, 4). The end of lower enclosure (4) is open ends, top of it has a annular frame (404), the motor (2) is located on the inner side of the lower enclosure (4), the output shaft (206) end is arranged on the lower enclosure (4) output shaft of the motor (2) is connected to an impeller (3), which is positioned between the annular frame (404) and a top plate (504) of upper enclosure (5); The sound absorbing foam (11) is arranged on the lower enclosure (4). The air inlet channel (12) formed by the sound absorbing foam (11) and outer surface of motor (2). When the motor (2) is rotating and driving impeller (3), air flows through air inlet channel (12), and the surface of motor (2) for heat exchange, the air after heat exchange flows out through the air outlet (13).

6. The blower according to claim 5, wherein the sound absorbing foam (11) is made of PE or EVA open foaming.

7. The blower according to claim 5, wherein the sound absorption coefficient of sound absorbing foam (11) is between 0.8 to 1 when frequency is between 500 to 4 KHz.

8. The blower according to claim 5, wherein the length to diameter ratio of the non-shaft part of the motor (2) rotor is between 3:1 to 6:1;

9. The blower according to claim 5, wherein the outer housing of motor (2) is made of thermal conductive material, to transfer the heat from the inside of the motor (2).

10. The blower according to claim 9, wherein the tubular motor housing (201) of motor (2) is made of aluminum alloy.

11. The blower according to claim 1, wherein the motor (2) coil (203) is slot-less tubular, mounted on the magnetic core of stator (202). The magnetic core of stator (202) uses low loss stamped silicon steel slot-less sheet stacked to form the tubular shape, this magnetic core of stator (202) is mounted on the tubular motor housing (201) of motor (2).

12. The blower according to claim 1, wherein the motor (2) is equipped with temperature sensor (211). The tubular motor housing (201), back cover (204), front cover (205) and printed circuit board (209) transfer heat from other parts of motor to the temperature sensor (211) to provide a temperature signal to the control center.

13. The blower according to claim 1, wherein the output shaft of motor (2) has water prove washer (9) and/or soft washer (10).

14. The blower according to claim 1, wherein the impeller (3) is made of material that density less than 1 g/mm.sup.3.

15. The blower according to claim 1, wherein the back plate of impeller (3) has at least one annular protuberance (306), which can improve the structural strength.

16. The blower according to claim 1, wherein the impeller (3) is affixed to the output shaft (206) of motor (2) directly, the output shaft (206) of motor (2) and impeller (3) contact part is serrated.

17. The blower according to claim 1, wherein the air outlet plan of blower is staggered from plane of impeller (3) blades.

18. The blower according to claim 1, wherein the lower enclosure (4) has an annular wall A(401) and an outer wall (402). The lower end of the annular wall A (401) and the lower end of the outer wall (402) are open. The upper end of the annular wall A(401) and the upper end of the outer wall (402) are provided with an annular frame (404), a space between the outer wall (402) and the upper enclosure (5) forms a gas path to the air outlet (13), a motor (2) is located on the inner side of the annular wall A (401), the output shaft end is arranged on the lower enclosure (4); The gas inlet structural member (6) is mounted between the annular wall A (401) and the outer wall (402).

19. The blower according to claim 1, wherein the inner ring of the annular frame (404) go inwards extend along downward, formed support rib (405), space between two adjacent support ribs (405) forms inlet hole A (406), the inner side of annular wall A (401) has motor mounting frame (407), which connected to support rib (405), the output shaft side of motor (2) fixed on the motor mounting frame (407); the bottom side of outer wall (402) outer edge formed half of outlet channel A (403).

20. The blower according to claim 1, wherein the upper enclosure (5) includes annular wall B (501), outlet channel B (502) and top plate (504). Once annular wall B (501) is mounted to the lower enclosure (4), it is located on the outside of outer wall (402). The top plate (504) on the annular wall B (501), the bottom side are open. The bottom side of annular wall B (501) outer edge forms half of outlet channel B (502).

21. The blower according to claim 1, wherein the annular flow channel between annular wall B(501) and outer wall (402) has 1 to 2 degree angle relative to axial, to make the outlet path increase the air flow cross area gradually to adapt to outlet tube cross section area.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0050] FIG. 1 is a three-dimensional view of the present invention;

[0051] FIG. 2A is a sectional view of the internal structure of the invention that the upper enclosure is coupled to the lower enclosure;

[0052] FIG. 2B is a also a sectional view of the internal structure of the first embodiment of the present invention;

[0053] FIG. 3A is exploded view of the first embodiment of present invention;

[0054] FIG. 3B is second exploded view of first embodiment of present invention;

[0055] FIG. 4 is the internal structure sectional view of the lower enclosure of the present invention;

[0056] FIG. 5 is the internal structure sectional view of the upper enclosure of the present invention;

[0057] FIG. 6 is an internal structure sectional view of the motor of the present invention;

[0058] FIG. 7 is an internal structure sectional view of the rotor of the present invention;

[0059] FIG. 8A is the first three-dimensional structure sectional view of the impeller of the present invention;

[0060] FIG. 8B is second three-dimensional structure sectional view of the impeller of the present invention;

[0061] FIG. 8C is third three-dimensional structure sectional view of the impeller of the present invention;

[0062] FIG. 9A is first three-dimensional structure sectional view of the air inlet structural part of first embodiment of the present invention;

[0063] FIG. 9B is second three-dimensional structure sectional view of the air inlet structural part of first embodiment of the present invention;

[0064] FIG. 10 is an internal structure sectional view of first embodiment of the present invention with impeller removed;

[0065] FIG. 11 is an internal structure sectional view of motor mounted to lower enclosure of the present invention;

[0066] FIG. 12 is another internal structure sectional view of motor mounted to lower enclosure of second embodiment of the present invention;

[0067] Where: 1 is blower, 2 is motor, 201 is tubular motor housing, 202 is magnetic core of stator, 203 is coil, 204 is back cover, 205 is front cover, 206 is output shaft, 207 is permanent magnets, 208 is balancing ring, 209 is printed circuit board, 210 is bearing, 211 is temperature sensor, 212 is wire mount, 213 is electrical wire, 214 is Y type connected coil terminal wires, 215 is bearing preload spring;

[0068] 3 is impeller, 301 is main blade, 302 is splitter blade, 303 is impeller hub, 304 is through hole, 305 is back plate, 306 is the annular protuberance;

[0069] 4 is lower enclosure, 401 is annular wall A, 402 is outer wall, 403 is outlet channel A, 404 is the annular frame, 405 is the support rib, 406 is the inlet hole A, 407 is the motor mounting frame;

[0070] 5 is upper enclosure, 501 is annular wall B, 502 is outlet channel B, 503 is mounting ear, and 504 is top plate;

[0071] 6 is air inlet structure, 601 is the flat plate, 602 is inlet tube, 603 is drainage hole, and 604 is inlet hole B;

[0072] 7 is motor support ring, 8 is noise silencing chamber, 9 is water prevent washer, 10 is soft washer, 11 is sound absorbing foam, 12 is air inlet channel, and 13 is air outlet;

DETAILED IMPLEMENTATION

[0073] The invention is further described with the following figures.

[0074] As shown in FIGS. 1 to 11, the blower 1 in this instance includes motor 2, impeller 3, lower enclosure 4, upper enclosure 5, air inlet structure 6 and motor support ring 7, in addition, lower enclosure 4 and upper enclosure 5 assembled together and forming blower 1 housing; the part of the upper enclosure 5 with lower enclosure 4 formed air outlet 13 as well, the air flow direction of air outlet 13 is tangent to outer surface of housing.

[0075] The lower enclosure 4 (from inside to outside) has annular wall A401 and outer wall 402, the bottom side of annular wall A and outer wall 402 is open, on the top is annular frame 404, outer wall 402 and annular wall A401 are coaxial; the inner ring of annular frame 404 extend downward to form support rib 405, two adjacent support ribs 405 forms inlet hole A406, the inner side of annular wall A401 has motor mounting frame 407, which connected to support rib 405, the output shaft side of motor 2 fixed on the motor mounting frame 407; the part of bottom side of outer wall 402 forms ½ outlet A403. The space between outer wall 402 and upper enclosure 5 connect with air outlet 13. The motor 2 located inner side of annular wall A401, output shaft fixed on the motor mounting frame 407.

[0076] The upper enclosure 5 includes annular wall B501, outlet channel B502, mounting ear 503 and top plate 504. Once annular wall B501 is connected to the lower enclosure 4, it is located on the outside of outer wall 402, and is coaxial setting with outer wall 402, annular wall A401; the top plate 504 is on the annular wall B501, the bottom side is open, the outer surface of annular wall B501 has mounting ears 503 align to circumferential direction, the bottom side of annular wall B501 outer edge forms half of outlet channel B as part of air outlet 13. the outlet channel B502 on the upper enclosure 5 close together with the outlet channel A403 on the lower enclosure forms the complete air outlet 13.

[0077] Unlike common impeller 3 installation method where a copper tube is embedded in the impeller 3 and then mounted on motor shaft, in this embodiment, impeller 3 is installed directly on the output shaft 206 of motor 2 in order to reduce total inertia. The meeting part of the motor 2 output shaft 206 and impeller 3 are serrated, increase touching area, to deal with the stress of acceleration and deceleration. The impeller 3 is placed in between the annular frame 404 and top plate 504 of upper enclosure 5. The impeller 3 includes main blades 301, splitter blades 302, wheel-hub 303 and back plate 305. There is a through hole 304 on the center of wheel-hub 303, one end of the wheel-hub 303 connect to the output shaft 206 of motor 2, another end fixed on the center of back plate 305 via structural ribs. On the back plate 305, around the wheel-hub 303, along the circumference direction evenly distributed many main blades 301 and splitter blades 302, the main blades 301 and splitter blades 302 are interlaced. One end of main blade 301 is located on the outer edge of the back plate 305. Another end connected to wheel-hub 303; one end of splitter blade 302 placed outer edge of back plate 305, another end of it has a gap to the wheel-hub 303. The thickness of the back plate 305 in this embodiment of the present invention is limited within 0.8 mm; the number of total number of blades is limited to under 17 (16 in this embodiment), main blade 301 is connected to the wheel-hub 303, the length of splitter blades 302 is ⅔ length of main blades 301. The thickness of splitter blade 302 is limited within 0.8 mm. The impeller 3 in this embodiment constructed with lightest engineering plastic (the density is less than or equal to 1 g/mm.sup.3, for example, polypropylene, LDPE, HDPE, TPV etc), and it can also satisfy the stress requirements when the impeller is working at high pressure, high rate of acceleration and deceleration. The diameter of impeller 3 is limited within the 50 mm. In order to prevent impeller 3 that made of low density plastic deforming under stress for a long time, improve the structural strength of the impeller 3, at least one annular protuberance 306 will be on the other side of back plate 305. There are three annular protuberances 306 in this embodiment, and are concentric setting with cross-section shaped inverted triangle.

[0078] Between the annular wall A401 and outer wall 402, there is a air inlet structure 6 on the lower enclosure, which is coaxial with the motor, and with annular frame 404. The above together forms noise silencing chamber 8, in order to reduce the airflow radiated noise of motor blower 1. The air inlet structure 6 includes flat plate 601 and inlet tube 602. The flat plate 601 is annular and can be affixed to the bottom of lower enclosure by ultrasonic or friction welding. Motor support ring 7 is fixed on the inner hole of flat plate 601. This motor support ring 7 and flat plate 601 together form supporting structure of non-output shaft end of motor 2. The motor support ring 7 in this design is made of soft biomedical compatible flexible silicon, over molded on the flat plate 601. There are number of inlet holes B604 on the flat plate 601 along the circumference direction, each hole has a connected inlet tube 602, and every inlet tube 602 placed in the space between annular wall A401 and outer wall 402. The space between inlet tube 602 top side and the frame 404 forms noise silencing chamber 8. Drainage holes 603 are provided on the flat plate 601.

[0079] At the output shaft end of motor 2 (the side connected to the impeller 3), the soft mounting can be used. In this embodiment, the motor 2 is mounted to the motor mounting shelf 407 by a washer 10, which made of a soft material (e.g. silicone). In this way, both ends of motor 2 are “soft” mounted on the housing, which can reduce the unbalanced vibration of rotor and impeller 3 to other parts in the blower 1 that increase radiate noise, then further reduce the total blower noise.

[0080] The output shaft end of motor 2 could also be mounted on a water seal circle washer 9. The inner circle extends outwards along axial direction; this water seal washer 9 will reduce the opportunity of water leaking into the bearing 210 part of motor 2, and also act as mounting washer of motor 2.

[0081] The output end of shaft of motor 2 is fixed on the motor mounting frame 407 of lower enclosure 4. As shown as FIGS. 6 and 7. The motor 2 includes rotor (includes two pole permanent magnets 207, output shaft made of stainless steel 206 and balancing ring 208), tubular toothless magnetic core of stator 202, tubular coil 203, tubular housing of motor 20, bearing 210, front cover 205 made of aluminum alloy, back cover 204 made of aluminum alloy, wire mount 212, printed circuit board 209, electrical wire 213, bearing preload spring 215 and temperature sensor 211, magnetic core of stator 202 that is fixed with high thermal conductivity of epoxy resin to inside the tubular motor housing 201. The coil 203 is a tubular, three phase two pole toothless. The magnetic core of stator 202 is built by low loss stamped steel sheet, toothless, multi-layered, tubular, and has low thermal resistance. The motor 2 is Brushless DC motor (BLDC). The coil 203 mounted on the inside of magnetic core of stator 202, use high thermal conductivity epoxy resin gluing on the magnetic core of stator 202, forms a low thermal resistance system that can disperse heat from coils 203 and magnetic stator core 202 for effective cooling. The rotor has an ultra-low inertia/power ratio, and the ratio of the length and diameter of non-shaft part of the rotor is 3:1-6:1.

[0082] The rotor is supported by two bearings mounted between the front cover 205 and back cover 204. Spring 215 provides preloading force to improve rotation accuracy, accurate shaft positioning, eliminate and reduce bearing 210 sliding, provides better control and reduces axial and radial displacements in the load condition such as high speed, high frequency acceleration, deceleration, and also reduce the motor driven blower vibration and noise. preloading on bearing 210 is critical to the performance and life span.

[0083] The electrical wire 213 soldered to the printed circuit board 209, the printed circuit board 209 is supported by a wire mount 212 that made of high thermal conductive plastic material. The wire mount 212 is fitted to the tubular motor housing 201 and fixed by heat conduction glue. There are three Y type connected coil terminal wires 214 pass printed circuit board 209, connect to the electrical wire 213, through the electrical wire 213 connect to external driver. The electrical wire 213 is soft flexible type and heat-resistant silicone insulated wire, has low noise, long life cycle and biocompatibility.

[0084] The temperature sensor 211 mounted on the printed circuit board 209, high thermal conductively tubular motor housing 201 can conduct heat from other parts of the motor to the temperature sensor 211, so that the temperature sensor can sense the motor's temperature accurately and indirectly, then this temperature signal is sent to the controller (e.g. processor). The printed circuit board 209 substrate is made of high thermal conductivity material (e.g. Aluminum sheet or FR4), and also connect to the electrical wire 213 that is used for temperature monitoring and safety protection of motor 2. The above mentioned motor structure provides low thermal resistance between all heat sources such as magnetic core of stator 202, coil 203, rotor and tubular motor housing 201, and temperature sensor 211. It has two advantages: The first is rapid heat dissipation from motor 2's heat source to tubular motor housing 201, make effective cooling; The second is more accuracy internal temperature sensing for monitoring the motor life and unsafe events, protect patients. In the case of temperature rising, the temperature sensor 211 will provide a high reliable signal to the control center, which is used to control the motor 2 to stop working when the motor 2 temperature is higher than the set value, so as to prevent bearing 210 damage, lubricant drying, end of the motor 2 life, or other safety risks caused by fault events.

[0085] In this embodiment, the air outlet 13 of blower 1 horizontal plane is not at same plane as blade of impeller 3. To eliminate tonal noise caused by pressure fluctuations in between the impeller blade and volute tongue. The annular flow channel between the annular wall B501 and outer wall 402 has 1-2° relative to the axial direction. By increasing the cross section area of airflow to transit gradually to the air outlet 13's cross section area.

[0086] The working principle of the embodiment:

[0087] The blower 1 in this embodiment is a high performance, single-stage axial air inlet, tangential direction air outlet 13. Has built-in noise reduction function. The blower 1 is used as a pressure and flow generator for Bi-level respirators for COPD or severe OSA. High flow treatment device, CPAP or any other respiratory device.

[0088] When motor 2 works, it drives the impeller 3 to rotate, the cold gas is driven by the impeller 3 of motor 2 through each inlet tube 602 of air inlet structure 6 along the housing's axial direction enters into the noise silencing chamber 8, then through the motor 2 surface for heat exchange. The curved channel is formed between the outer wall 402 of lower enclosure 4 and annular wall B501 of upper enclosure 5 (as shown in the curved arrow in FIG. 2A), which is used to receive and slow down the air flow from the impeller 3 to generate pressure. In this embodiment, the gas flow output of the impeller 3 is unlike the flow of most existing blower, which flows to the air outlet 13 immediately, instead the compressed airflow will rotate along the center axis of enclosure first, then through the space between annular frame 404 and top plate 504, and flow downwards to the space between outer wall 402 of lower enclosure 4 and annular wall B501 of upper enclosure 5, finally it flows out from air outlet 13; By this way, it can eliminate noise generated by pressure fluctuations between the impeller 3 blade and volute tongue. In this embodiment, structure of impeller 3 can minimize the rotor inertia, so as to improve the response speed of the Bi-level respirator system.

[0089] Inlet hole A406 is one of the major noise sources and outwards transmission points of blower 1. The gas flow path of impeller 3 is designed in such a away to: reduce thereby produced noise and gas flow resistance as much as possible due to the interaction between potential non-uniform flow fields, turbulence, turbulence and rigid structure. One of the important sources of noise is sudden changes in flow profile (shape and speed), in order to reduce the noise, slowly changes the flow curve along the inlet flow path (see the arrow in FIG. 8C), and then gas enter the pressure formation zone.

[0090] This embodiment, the current popular single large round air inlet hole is replaced by multiple small holes. Gas flow enters the noise silencing chamber 8 through many inlet tube 602, the space between the annular wall A401 and outer wall 402 with inlet tube 602 together forms the gas flow rectifier and noise trap, reduces the inlet flow noise effectively. In order to optimize the noise reduction effect and inlet resistance index, we define all the total inlet tube 602's cross section area is the equivalent area of the blower's cross section area of gas exhaust tube (air outlet 13).

[0091] The inlet airflow from the noise trap region flows along surface of the motor 2, provide effective cooling air for the motor 2 (shown as the arrows in FIG. 2B). The surface of the motor 2 can also be made with fins to further improve the heat exchange rate. The greater the gas movement load of the impeller 3, the greater the heat generated by motor 2. But meanwhile, the added heat will be carried away by increased cold gas flow. Thus, this approach will keep the motor effective cooling under all operation conditions.

[0092] A drainage hole 603 in the flat plate 601 provides a drainage solution that when water accidentally pours back into the blower 1 from the humidifier, the water will first fill the space formed between the annular wall A401 and outer wall 402 that could store certain amount of water. If the amount of water poured back exceeds the containing volume, the additional water will flow along the arrow in the FIG. 10, filling the gap between the blower enclosure and drainage hole 603 and slowly draining the water.

Second Embodiment

[0093] As shown in FIG. 12, the difference between first embodiment and second embodiment is that the second embodiment removed the air inlet structure 6, instead the sound absorbing foam 11 is mounted on the inner face of annular wall A401 of the lower enclosure 4. The air inlet channel 12 is formed in between the sound absorbing foam 11 and outer surface of motor 2. The outside air enters from bottom of lower enclosure 4, heat is exchanged with the surface of motor 2 through air inlet channel 12, the sound absorbing foam can reduce the noise. In the second embodiment, the sound absorbing foam is made of PE or EVA open foaming, the sound absorption coefficient of the air inlet sound absorbing foam is 0.8-1 between the frequency of 500-4 KHz.

[0094] The blower provided by this invention can be applied to where the fast response time, easy to drive and control, higher output pressure, high flow rate, safety and high reliability, low noise, small size, low cost pressurized treatment gas source is required, for example, BiPAP.