US20090169399A1

US20090169399A1 - Ultra-thin miniature pump

Info

Publication number: US20090169399A1
Application number: US12/005,348
Authority: US
Inventors: Xin-Yi Wu; Tsung-Wen Huang; Kuo-Feng Chen; Yih-Ru Jiang
Original assignee: Metal Industries Research and Development Centre
Current assignee: Metal Industries Research and Development Centre
Priority date: 2007-12-27
Filing date: 2007-12-27
Publication date: 2009-07-02

Abstract

An ultra-thin miniature pump applied to transport a fluid includes a main body, a rotor, and a stator. The main body includes a cover part and a bottom part. A joint surface between the cover part and the bottom part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body. The rotor disposed in the chamber includes a magnet set, an impeller, and a central shaft. The magnet set is connected on the surface of the impeller, and the impeller with the magnet set is aligned by the central shaft and rotates in coaxial. The stator disposed in the chamber includes a plurality of coils corresponding to the magnet set axially. The coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port.

Description

BACKGROUND OF THE INVENTION

1. Field of Invention
The present invention relates to an ultra-thin miniature pump, especially for an ultra-thin miniature pump, which utilizes a design of axial-flux micromotor and possesses advantages of structure miniaturization, high rotating torque, high head rise, and excellent heat dissipation capability.
2. Related Art
Miniature pumps are very important units which are employed in various fields such as liquid cooling systems, transporting devices of fuel cells, and artificial hearts. Therefore, it is a general objective of designers and manufacturers to design and manufacture the miniature pumps which include advantages of good anti-leakage capability, high rotating torque, high head rise, excellent heat dissipation capability, and structure miniaturization.
A centrifugal pump mainly includes coils of a stator, magnets of a rotor, and an impeller. The centrifugal pump utilizes the flow of electric currents in the coils of the stator to create magnetic fields. Then, the magnetic fields act upon the magnets of the rotor to generate a magnetic force, and the impeller is rotated by the magnetic force to transport fluids. According to various motor disposing types of the pumps, the pumps could be divided into external motor pumps and internal motor pumps. The external motor pumps and the internal motor pump are described respectively as following:

- a. The external motor pump has some features that its motor and pump are split and a transmission shaft between the motor and the pump is utilized to transmit motive force. There are advantages of the external motor pump that the external motor pump is easy to be assembled and the pump has a low leakage rate. However, due to the longer transmission shaft between the pump and the motor, the external motor pump would need bigger space for assembling. Moreover, it is more difficult to align a shaft of the pump with a shaft of the motor. If the shaft of the pump is not aligned with the shaft of the motor, the external motor pump will generate more vibratile noise and has a shorter lifetime.
- b. The internal motor pump has a feature that its motor is disposed inside the pump and located in the center of an impeller. Since a diameter of the motor is restricted with the shape of vanes of the impeller, rotating torsion of the motor will be constricted. If the diameter of the motor is increased, the size of the vanes will be constricted and the flow rate or output flow pressure will be limited. Moreover, since the motor is located in the center of the impeller, heat of the motor is difficult to dissipate and a lifetime of the motor will be influenced.

Accordingly, the miniature pumps of the prior art mostly belong to the internal motor pumps for reasons of structure miniaturization and little vibratile noise. However, the miniature pumps of the prior -art, which are disclosed by Taiwan Patent Issued No. 00587784, M321653 and United States Patent Issued No. 20030072656A1, generally adopt a design of radial-flux motor and they are hard to avoid some drawbacks of low rotating torque as well as low head rise and poor heat dissipation capability of their motors. The above drawbacks are difficult problems what the people of the related fields want to solve.

SUMMARY OF THE INVENTION

In view of the above problems, an object of the present invention is to provide an ultra-thin miniature pump to solve drawbacks of miniature pumps of the prior art, such as low rotating torque, low head rise and poor heat dissipation capability of pumps, and achieve structure miniaturization.
According to one embodiment of the present invention, an ultra-thin miniature pump is provided. The ultra-thin miniature pump of the present invention is applied to transport a fluid and comprises a main body, a rotor, and a stator. The main body includes a cover part and a bottom part. A joint surface between the cover part and the bottom part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body. The rotor disposed in the chamber includes a magnet set, an impeller, and a central shaft. The magnet set is connected on a surface of the impeller, and the impeller with the magnet set is aligned by the central shaft and rotates in coaxial manner. The stator disposed in the chamber includes a plurality of coils corresponding to the magnet set axially. The coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port. A sealing layer seals the stator, and the fluid and the coil are isolated by this sealing layer.
According to another embodiment of the present invention, an ultra-thin miniature pump is provided. The ultra-thin miniature pump of the present invention is applied to transport a fluid and comprises a main body, a rotor, a stator, and a sealing layer. The main body includes a cover part, a body part, and a bottom part combined in sequence. A joint surface between the cover part and the body part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body. The rotor disposed in the chamber includes a magnet set, an impeller, and a central shaft. The magnet set is connected on a surface of the impeller, and the impeller and the magnet set are aligned by the central shaft and rotate in coaxial manner. The stator disposed in the chamber of the body part and the bottom part includes a plurality of coils corresponding to the magnet set axially. The coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port. The sealing layer located in a portion of the chamber of the body part and the bottom part seals the coils and prevents the fluid from leaking through a joint surface between the body part and the bottom part.
The ultra-thin miniature pump of the present invention utilizes a design of axial-flux micromotor. Since the magnet set is integrated with the impeller and the coils are axially aligned with the magnet set, the ultra-thin miniature pump of the present invention is light in weight and compact in size. Furthermore, since the magnet set is designed according to the shape of impeller of vortex pumps, there is more space for a motor of the ultra-thin miniature pump to increase its diameter and then the rotating torque and the head rise of the pump are promoted. Moreover, since the motor has larger dissipation space, it will prevent the motor from overheating and increase the lifetime of the motor.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given herein below for illustration only, and which thus is not limitative of the present invention, and wherein:

FIG. 1 is a schematic diagram of an ultra-thin miniature pump according to a first exemplary embodiment of the present invention;

FIG. 2 is an exploded diagram of the ultra-thin miniature pump according to the first exemplary embodiment of the present invention; and

FIG. 3 is an exploded diagram of an ultra-thin miniature pump according to a second exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The features and practice of the present invention will be illustrated below in detail through preferred embodiments with reference to the accompanying drawings.
Referring to FIG. 1, FIG. 1 illustrates a schematic diagram of an ultra-thin miniature pump according to a first exemplary embodiment of the present invention. As shown in FIG. 1, an ultra-thin miniature pump 10 according to a first exemplary embodiment of the present invention is utilized to transport a fluid (not shown in FIG. 1). The fluid could be coolant of liquid cooling systems, fuel of fuel cells, or blood of artificial hearts, etc.
Referring to FIG. 2, FIG. 2 illustrates an exploded diagram of the ultra-thin miniature pump according to the first exemplary embodiment of the present invention. As shown in FIG. 2, the ultra-thin miniature pump 10 according to the first exemplary embodiment of the present invention comprises a main body 12, a rotor 14, and a stator 16. The main body 12 includes a cover part 18 and a bottom part 20. Therein, a joint surface 22 between the cover part 18 and the bottom part 20 possesses an anti-leakage device, such as an O-ring gasket 24 which is disposed in a groove 26 between the cover part 18 and the bottom part 20 of the first embodiment. A plurality of screws 28 are utilized to bolt and fix the cover part 18 and the bottom part 20, and then the O-ring gasket 24 is compressed to keep an anti-leakage condition of the main body 12. Furthermore, a chamber (not shown in FIG. 2) including a suction port 30 and a discharge port 32 is formed inside the main body 12, and the suction port 30 and the discharge port 32 are disposed in a side of the cover part 18. The bottom part 20 includes a fixed base 34, and a bearing 36, such as an oil-free lubrication bearing, is disposed in the fixed base 34. It is noted that the suction port 30 and the discharge port 32 are not restricted to be disposed in the cover part 18. In other embodiments, the suction port 30 and the discharge port 32 may be disposed in the bottom part 20 depending on various designs. Moreover, the fixed base 34 is not restricted to be disposed in the bottom part 20. In other embodiments, the fixed base 34 may be disposed in the cover part 18 depending on various designs, or the fixed base 34 may be disposed in both of the cover part 18 and the bottom part 20.
As shown in FIG. 2, the rotor 14 is disposed in the chamber, and it includes a magnet set 38, an impeller 40, and a central shaft 42. Therein, the magnet set 38 could be an annular magnet, and the annular magnet is fixed on a downward surface (not shown in FIG. 2) of the impeller 40 and located between the plurality of vanes 44 of the impeller 40 and the central shaft 42. The downward surface of the impeller 40 includes an annular cavity (not shown in FIG. 2) located between the vanes 44 of the impeller 40 and the central shaft 42, and the annular magnet is corresponding to the annular cavity and fixed in the annular cavity by adhering or embedding. Moreover, the central shaft 42 is connected to the bearing 36, which is disposed in the fixed base 34, for rotating, and the impeller 40 with the magnet set 38 are connected to the central shaft 42 and aligned by the central shaft 42. Then, the impeller 40 and the magnet set 38 rotate in coaxial manner.
As shown in FIG. 2, the stator 16 is disposed inside a cavity 46 of the chamber in the bottom part 20, and it includes a plurality of coils 48 corresponding to the magnet set 38 axially and a substrate 50 for disposing the coils 48. Therein, the coils 48 and the magnet set 38 generate an axial magnetic flux to make the impeller 40 rotate for transporting the fluid from the suction port 30 to the discharge port 32. It is noted that the magnet set 38 may include a plurality of magnets, and the magnets are corresponding to the coils 48 respectively and fixed on the downward surface of the impeller 40.
As shown in FIG. 2, the main body 12 further includes at least an opening (not shown in FIG. 2), and the coils 48 are electrically connected outside of the main body 12 through the opening. Furthermore, a sealing layer (not shown in FIG. 2) covers the cavity 46 to seal the coils 48 and the opening to prevent the fluid from leaking through the opening, and the fluid and the coils 48 are isolated by the sealing layer. Moreover, there is a stripper (not shown in FIG. 2) disposed between an inside wall of the main body 12 and the impeller 40. The stripper is an isolating wall located between the suction port 30 and the discharge port 32 to prevent the pressurized fluid in the outlet region(not shown in FIG. 2) from flowing into the inlet region(not shown in FIG. 2) at low pressure. The ultra-thin miniature pump 10 of the present invention utilizes a driver (not shown in FIG. 2), which is disposed outside of the main body 12 or on the substrate 50, to make the coils 48 generate an axial magnetic flux, and then the axial magnetic flux make the magnet set 38, which is connected on the impeller 40, rotate for transporting the fluid from the suction port 30 to the discharge port 32.
Referring to FIG. 3, FIG. 3 illustrates an exploded diagram of an ultra-thin miniature pump according to a second exemplary embodiment of the present invention. As shown in FIG. 3, an ultra-thin miniature pump 60 according to a second exemplary embodiment of the present invention is utilized to transport a fluid (not shown in FIG. 3), and it comprises a main body 62, a rotor 64, a stator 66, and a sealing layer (not shown in FIG. 3).
As shown in FIG. 3, the main body 62 includes a cover part 68, a body part 70, and a bottom part 72. Therein, a joint surface 74 between the cover part 68 and the body part 70 possesses an anti-leakage device, such as an O-ring gasket 76 which is disposed in a groove 78 between the cover part 68 and the body part 70 of the present embodiment. A plurality of screws 80 are utilized to bolt and fix the cover part 68, the body part 70, and the bottom part 72, and then the O-ring gasket 76 is compressed to keep an anti-leakage condition of the main body 62. Furthermore, a chamber (not shown in FIG. 3) including a suction port 82 and a discharge port 84 is formed inside the main body 62, and the suction port 82 and the discharge port 84 are disposed in a side of the cover part 68. The bottom part 72 includes a fixed base 86, and a bearing 88, such as an oil-free lubrication bearing, is disposed in the fixed base 86. It is noted that the suction port 82 and the discharge port 84 are not restricted to be disposed in the cover part 68. In other embodiments, the suction port 82 and the discharge port 84 may be disposed in the body part 70 depending on various designs. Moreover, the fixed base 86 is not restricted to be disposed in bottom part 72. In other embodiments, the fixed base 86 may be disposed in the cover part 68 depending on various designs, or the fixed base 86 may be disposed in both of the cover part 68 and the bottom part 72.
As shown in FIG. 3, the rotor 64 is disposed in the chamber, and it includes a magnet set 90, an impeller 92, and a central shaft 94. Therein, the magnet set 90 could be an annular magnet, and the annular magnet is fixed on a downward surface (not shown in FIG. 3) of the impeller 92 and located between the plurality of vanes 96 of the impeller 92 and the central shaft 94. The downward surface of the impeller 92 includes an annular cavity (not shown in FIG. 3) located between the vanes 96 of the impeller 92 and the central shaft 94, and the annular magnet is corresponding to the annular cavity and fixed in the annular cavity by adhering or embedding. Moreover, the central shaft 94 is connected to the bearing 88, which is disposed in the fixed base 86, for rotating, and the impeller 92 with the magnet set 90 are connected to the central shaft 94 and aligned by the central shaft 94. Then, the impeller 92 and the magnet set 90 rotate in coaxial manner.
As shown in FIG. 3, the stator 66 is disposed inside a cavity 98 of the chamber in the body part 70 and the bottom part 72, and it includes a plurality of coils 100 corresponding to the magnet set 90 axially and a substrate 102 for disposing the coils 100. Therein, the coils 100 and the magnet set 90 generate an axial magnetic flux to make the impeller 92 rotate for transporting the fluid from the suction port 82 to the discharge port 84. It is noted that the magnet set 90 may include a plurality of magnets, and the magnets are corresponding to the coils 100 respectively and fixed on the downward surface of the impeller 92.
As shown in FIG. 3, the main body 62 further includes at least an opening 104 disposed in the bottom part 72, and the coils 100 are electrically connected outside of the main body 62 through the opening 104. The opening 104 is not restricted to be disposed in the bottom part 72. In other embodiment, the opening 104 may be disposed in a side of the body part 70.
As shown in FIG. 3, the sealing layer is located in a portion of the chamber of the body part 70 and the bottom part 72 and it covers the cavity 98 to seal the coils 100 and the opening 104 to prevent the fluid from leaking through the opening 104 and a joint surface 106 between the body part 70 and the bottom part 72, and the fluid and the coils 100 are isolated by the sealing layer. Moreover, there is a stripper (not shown in FIG. 3) disposed between an inside wall of the main body 62 and the impeller 92. The stripper is an isolating wall located between the suction port 82 and the discharge port 84 to prevent the pressurized fluid in the outlet region(not shown in FIG. 3) from flowing into the inlet region(not shown in FIG. 3) at low pressure. The ultra-thin miniature pump 60 of the present invention utilizes a driver (not shown in FIG. 3), which is disposed outside of the main body 62 or on the substrate 102, to make the coils 100 generate an axial magnetic flux, and then the axial magnetic flux make the magnet set 90, which is connected on the impeller 92, rotate for transporting the fluid from the suction port 82 to the discharge port 84.
Compared to the prior art, the ultra-thin miniature pump of the present invention utilizes a design of axial magnetic flux. Since the magnet set is integrated with the impeller and the coils are axially aligned with the magnet set, the ultra-thin miniature pump of the present invention is light in weight and compact in size. Furthermore, since the magnet set is designed according to the shape of impeller of vortex pumps, there is more space for a motor of the ultra-thin miniature pump to increase its diameter and then the rotating torque and the head rise of the pump are promoted. Moreover, since the motor has larger dissipation space, it will prevent the motor from overheating and increase the lifetime of the motor.

Claims

1. An ultra-thin miniature pump, which is applied to transport a fluid, comprising:

a main body including a cover part and a bottom part, wherein a joint surface between the cover part and the bottom part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is disposed inside the main body;

a rotor being disposed in the chamber and including a magnet set, an impeller, and a central shaft, wherein the magnet set is connected on a surface of the impeller, and the impeller and the magnet set are aligned by the central shaft and rotate in coaxial manner; and

a stator being disposed in the chamber and including a plurality of coils corresponding to the magnet set axially, wherein the coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port.

2. The ultra-thin miniature pump as claimed in claim 1, wherein the cover part includes a fixed base and a bearing disposed in the fixed base, and the central shaft is connected to the bearing for rotating.

3. The ultra-thin miniature pump as claimed in claim 1, wherein the bottom part includes a fixed base and a bearing disposed in the fixed base, and the central shaft is connected to the bearing for rotating.

4. The ultra-thin miniature pump as claimed in claim 1, wherein the anti-leakage device is a gasket which is disposed between the cover part and the bottom part.

5. The ultra-thin miniature pump as claimed in claim 1, wherein the magnet set is an annular magnet, and the annular magnet is fixed on the surface of the impeller and located between a plurality of vanes of the impeller and the central shaft.

6. The ultra-thin miniature pump as claimed in claim 5, wherein the surface of the impeller includes an annular cavity located between the vanes of the impeller and the central shaft, and the annular magnet is corresponding to the annular cavity and fixed therein.

7. The ultra-thin miniature pump as claimed in claim 1, wherein the magnet set includes a plurality of magnets, and the magnets are corresponding to the coils respectively and fixed on the surface of the impeller.

8. The ultra-thin miniature pump as claimed in claim 1, wherein the coils are sealed by a sealing layer.

9. The ultra-thin miniature pump as claimed in claim 8, wherein the main body further includes at least an opening, the coils electrically connect outside of the main body, and the coils and the opening are sealed by the sealing layer.

10. The ultra-thin miniature pump as claimed in claim 1, wherein a stripper is disposed between an inside wall of the main body and the impeller, and the stripper is located between the suction port and the discharge port to prevent a pressurized fluid in an outlet region from flowing into an inlet region at low pressure.

11. An ultra-thin miniature pump, which is applied to transport a fluid, comprising:

a main body including a cover part, a body part, and a bottom part combined in sequence, wherein a joint surface between the cover part and the body part possesses an anti-leakage device, and a chamber including a suction port and a discharge port is formed inside the main body;

a rotor being disposed in the chamber and including a magnet set, an impeller, and a central shaft, wherein the magnet set is connected on a surface of the impeller, and the impeller and the magnet set are aligned by the central shaft and rotate in coaxial manner;

a stator being disposed in the chamber of the body part and the bottom part and including a plurality of coils corresponding to the magnet set axially, wherein the coils and the magnet set generate an axial magnetic flux to make the impeller rotate for transporting the fluid from the suction port to the discharge port; and

a sealing layer located in a portion of the chamber of the body part and the bottom part for sealing the coils and preventing the fluid from leaking through a joint surface between the body part and the bottom part.

12. The ultra-thin miniature pump as claimed in claim 11, wherein the cover part includes a fixed base and a bearing disposed in the fixed base, and the central shaft is connected to the bearing for rotating.

13. The ultra-thin miniature pump as claimed in claim 11, wherein the bottom part includes a fixed base and a bearing disposed in the fixed base, and the central shaft is connected to the bearing for rotating.

14. The ultra-thin miniature pump as claimed in claim 11, wherein the anti-leakage device is a gasket which is disposed between the cover part and the body part.

15. The ultra-thin miniature pump as claimed in claim 11, wherein the magnet set is an annular magnet, and the annular magnet is fixed on the surface of the impeller and located between a plurality of vanes of the impeller and the central shaft.

16. The ultra-thin miniature pump as claimed in claim 15, wherein the surface of the impeller includes an annular cavity located between the vanes of the impeller and the central shaft, and the annular magnet is corresponding to the annular cavity and fixed in the annular cavity.

17. The ultra-thin miniature pump as claimed in claim 11, wherein the magnet set includes a plurality of magnets, and the magnets are corresponding to the coils respectively and fixed on the surface of the impeller.

18. The ultra-thin miniature pump as claimed in claim 11, wherein the main body further includes at least an opening, the coils electrically connect outside of the main body, and the coils and the opening are sealed by the sealing layer.

19. The ultra-thin miniature pump as claimed in claim 11, wherein a stripper is disposed between an inside wall of the main body and the impeller, and the stripper is located between the suction port and the discharge port to prevent a pressurized fluid in an outlet region from flowing into an inlet region at low pressure.