Fluid pump and use thereof for cooling electric vehicle charging pile

Abstract

A fluid pump, capable of being used for cooling an electric vehicle charging pile. The fluid pump comprises a high-pressure fluid region (30) produced by a pump head (20) and a low-pressure fluid region (40) surrounding the high-pressure fluid region (30); fluid is adapted to be discharged via the high-pressure fluid region (30) from the low-pressure fluid region (40); and a rotor (11) of a motor is cooled by low-pressure fluid within the low-pressure fluid region (40). The fluid pump has low requirements on the compression resistance of a rotor material. Even if internal leakage occurs in the high-pressure fluid region, the fluid pump can still work without failure.

Description

Fluid pump and its use for cooling electric vehicle charging pile Technical Field

[0001] The present invention relates to a pump, in particular to a fluid pump and an application thereof in cooling an electric vehicle charging pile. Background Art

[0002] A fluid pump typically consists of a motor and a pump head. Its operating principle is that the motor's shaft drives the impeller inside the pump head, causing the liquid to swirl, thereby drawing in and out. Because the high-speed rotation of the motor's rotor generates a large amount of heat, liquid is often used to cool the rotor. However, the rotors of existing fluid pumps are typically cooled by high-pressure fluid pressurized by the impeller. This not only places high demands on the rotor material's compressive strength, but also makes the pump prone to internal leakage and subsequent failure.

[0003] Summary of the Invention

[0004] In view of this, the present invention aims to provide a fluid pump and its use for cooling an electric vehicle charging pile.

[0005] To this end, on one hand, the present invention provides a fluid pump, which includes a high-pressure fluid area generated by the pump head and a low-pressure fluid area surrounding the high-pressure fluid area, the fluid is suitable for being discharged from the low-pressure fluid area via the high-pressure fluid area, and the rotor of the motor is cooled by the low-pressure fluid in the low-pressure fluid area.

[0006] On the other hand, the present invention provides use of the fluid pump for cooling an electric vehicle charging pile.

[0007] Compared to existing technologies, the rotor of the fluid pump of the present invention is cooled by a low-pressure fluid, effectively reducing the pressure resistance requirements of the rotor material. More importantly, even if a leak occurs in the high-pressure fluid area, the leaked fluid will flow into the low-pressure fluid area because the high-pressure fluid area is surrounded by the low-pressure fluid area, and the fluid pump will continue to operate without failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG1 is a perspective schematic diagram of a fluid pump according to a first embodiment of the present invention;

[0009] FIG2 is a schematic diagram of the interior of the fluid pump shown in FIG1 ;

[0010] FIG3 is a schematic internal diagram of a fluid pump according to a second embodiment of the present invention.

[0011] DETAILED DESCRIPTION

[0012] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments to make the technical solutions and beneficial effects of the present invention more clearly understood. It should be understood that the drawings are provided for reference and illustration only and are not intended to limit the present invention. The dimensions shown in the drawings are only for the purpose of clarification and do not limit the proportional relationship.

[0013] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the invention.

[0014] 1 and 2 , a fluid pump according to a first embodiment of the present invention includes a motor 10 and a pump head 20. The fluid pump includes a high-pressure fluid region 30 (roughly corresponding to the region within the dashed box shown in FIG2 ) generated by the pump head 20 and a low-pressure fluid region 40 (roughly corresponding to the region outside the dashed box shown in FIG2 ) surrounding the high-pressure fluid region 30. Fluid is adapted to be discharged from the low-pressure fluid region 40 through the high-pressure fluid region 30. The rotor 11 of the motor 10 is cooled by the low-pressure fluid within the low-pressure fluid region 40, thereby reducing the pressure resistance requirements for the rotor 11 material. Specifically, the low-pressure fluid region 40 surrounds the high-pressure fluid region 30. Thus, even if a leak occurs in the high-pressure fluid region 30, since the high-pressure fluid region 30 is surrounded by the low-pressure fluid region 40, the leaked fluid will flow into the low-pressure fluid region 40, and the fluid pump can continue to operate without failure.

[0015] Specifically, in this embodiment, the motor 10 includes the rotor 11 and a stator 12 surrounding the rotor 11. An annular air gap 13 is defined between the stator 12 and the rotor 11, thereby enabling the rotor 11 to rotate relative to the stator 12. The low-pressure fluid region 40 includes the annular air gap 13 between the stator 12 and the rotor 11 of the motor 10. As a result, the rotor 11 can be cooled by the low-pressure fluid in the low-pressure fluid region 40 (specifically, the annular air gap 13).

[0016] More specifically, in this embodiment, the rotor 11 includes a rotor core 110 and a rotating shaft 112 connected to the rotor core 110 for synchronous rotation. The stator 12 includes a sleeve-shaped stator housing 120, a stator core, and windings (not shown) housed within the stator housing 120. The stator housing 120 includes an inner cylinder 121, an outer cylinder 122, and an annular end wall 123 connecting one end of the inner cylinder 121 and one end of the outer cylinder 122. The rotor core 110 is housed within the inner cylinder 121 of the stator housing 120, forming the annular air gap 13 therebetween. In this embodiment, a cavity 111 is defined between the axial top end of the rotor core 110 and the annular end wall 123, communicating with the annular air gap 13.

[0017] In this embodiment, the pump head 20 includes a pump housing 21, an end cover 22, a front cover 23, an impeller 24, a rear cover 25, and a sealing cover 26. A liquid outlet pipe 216 is provided on one radial side of the pump housing 21. The end cover 22 and the stator housing 120 are respectively located at the axial ends of the pump housing 21 and are fixedly connected (e.g., by screws). A liquid inlet pipe 222 is provided on the end of the end cover 22 facing away from the pump housing 21. The front cover 23 and the rear cover 25 are fixedly connected to the pump housing 21 (e.g., by screws), and the front cover 23 and the rear cover 25 together enclose a receiving chamber 250 for accommodating the impeller 24. The sealing cover 26 is fixedly connected to the rear cover 25 (e.g., by screws). The rotating shaft 112 of the rotor 11 passes through the front cover 23 and is connected to the impeller 24 to drive the impeller 24 to rotate.

[0018] In this embodiment, in addition to the annular air gap 13, the low-pressure fluid region 40 also includes an annular cavity 41 surrounding the high-pressure fluid region 30. In this embodiment, the annular cavity 41 is enclosed by the stator housing 120, the pump housing 21, the end cover 22, the front cover 23, and the sealing cover 26.

[0019] Specifically, the annular cavity 41 includes a liquid inlet cavity 221 formed by the end cover 22 and the sealing cover 26, one or more first through holes 212 axially penetrating the pump housing 21 and distributed circumferentially, and a radial flow channel 125 formed by the front cover 23 and the annular end wall 123 of the stator housing 120, wherein the tube cavity of the liquid inlet pipe 222 is connected to the liquid inlet cavity 221, the liquid inlet cavity 221 is connected to the axial upper end of the first through hole 212, the axial lower end of the first through hole 212 is connected to the radial flow channel 125, and the radial flow channel 125 is connected to the annular air gap 13 located at the axial lower end of the annular cavity 41 through the cavity 111.

[0020] In this embodiment, the front cover 23 is provided with a liquid inlet 231 that penetrates the front cover 23 at least in the axial direction. The liquid inlet 231 is axially adjacent to the annular air gap 13 and communicates with the cavity 111 and / or the radial flow channel 125. The rear cover 25 is provided with a liquid outlet 251 that penetrates the rear cover 25 at least in the axial direction and is axially away from the annular air gap 13. Both the liquid outlet 251 and the liquid inlet 231 communicate with the receiving cavity 250.

[0021] Preferably, in order to improve the fluid dynamics of the fluid in the receiving chamber 250, the end face of the front cover 23 and the end face of the rear cover 25 are respectively recessed corresponding to the receiving chamber 250 to form an annular fluid groove 234, 252, and the liquid inlet 231 is preferably arranged at the starting point of the corresponding fluid groove 234, and the liquid outlet 251 is preferably arranged at the end point of the corresponding fluid groove 252.

[0022] In this embodiment, the rear cover 25 and the sealing cover 26 together enclose a liquid outlet cavity 254, which is in communication with the liquid outlet 251 and the liquid outlet pipe 216. It is not difficult to find that in this embodiment, the liquid inlet cavity 221 and the liquid outlet cavity 254 are respectively located at the axial ends of the sealing cover 26.

[0023] Preferably, the pump head 20 further includes a relief valve 50, which is located between the high-pressure fluid region 30 and the low-pressure fluid region 40. When the fluid pressure in the high-pressure fluid region 30 exceeds a rated value, the relief valve 50 opens, allowing a small amount of fluid to leak from the high-pressure fluid region 30 into the low-pressure fluid region 40, thereby reducing the fluid pressure in the high-pressure fluid region 30. When the fluid pressure in the high-pressure fluid region 30 returns to below the rated value, the relief valve 50 closes.

[0024] Specifically, in this embodiment, the relief valve 50 is disposed on the sealing cover 26. A second through hole 263 is provided in the middle of the sealing cover 26, extending axially therethrough. The relief valve 50 is disposed within the second through hole 263 of the sealing cover 26. When the relief valve 50 is closed, the liquid outlet chamber 254 and the liquid inlet chamber 221 are not directly connected to each other. When the relief valve 50 is open, the liquid outlet chamber 254 is directly connected to the liquid inlet chamber 221 via the second through hole 263.

[0025] When the fluid pump of this embodiment is in use, fluid enters the liquid inlet chamber 221 from the liquid inlet pipe 222, then passes through the first through-hole 212, the radial flow channel 125, and the cavity 111 into the annular air gap 13 to cool the rotor 11. (Because the overflow valve 50 is normally closed, the fluid cannot directly enter the liquid outlet chamber 254 from the liquid inlet chamber 221.) During this process, the fluid is in a low-pressure state. In other words, in this embodiment, the fluid enters the annular air gap 13 from the annular cavity 41 to cool the rotor 11.

[0026] The fluid then flows back into the annular cavity 41 (specifically, the radial flow channel 125), enters the receiving chamber 250 through the liquid inlet 231, and is driven by the impeller 24 to become a high-pressure fluid. The fluid then flows out of the liquid outlet 251 into the liquid outlet chamber 254, and is finally discharged from the liquid outlet pipe 216. During this process, the fluid is in a high-pressure state. Therefore, it can be said that the high-pressure fluid region 30 in this embodiment includes the receiving chamber 250 and the liquid outlet chamber 254.

[0027] It is not difficult to find that in this embodiment, the low-pressure fluid region 40 surrounds the high-pressure fluid region 30 circumferentially via the first through-hole 212, surrounds the high-pressure fluid region 30 at the axial upper end via the liquid inlet cavity 221, and surrounds the high-pressure fluid region 30 at the axial lower end via the radial flow channel 125, the cavity 111, and the annular air gap 13, thereby achieving full omnidirectional encirclement of the high-pressure fluid region 30. Therefore, even if the fluid pressure in the high-pressure fluid region 30 exceeds the rated value, the relief valve 50 opens, and some fluid flows from the liquid outlet cavity 254 into the liquid inlet cavity 221 (i.e., leakage occurs in the high-pressure fluid region 30), since the high-pressure fluid region 30 is fully surrounded by the low-pressure fluid region 40, the leaked fluid will also flow into the low-pressure fluid region 40, and the fluid pump can still operate without failure.

[0028] It will be appreciated that the specific structures of the low-pressure fluid region 40 and the high-pressure fluid region 30 and the specific fluid flow paths described above are shown for illustrative purposes only. In other embodiments, the low-pressure fluid region 40 may not include the cavity 111, or the low-pressure fluid region 40 may employ alternative structures to the first through-hole 212 to connect the liquid inlet cavity 221 and the annular air gap 13. In some embodiments, the high-pressure fluid region 30 may include only a single cavity, rather than being divided into the aforementioned receiving cavity 250 and liquid outlet cavity 254.

[0029] Please refer to Figure 3. The fluid pump of the second embodiment of the present invention is substantially the same as the fluid pump of the first embodiment described above. The similarities are not repeated here. The main difference between the two is that the rotor 11 of this embodiment is cooled by a portion of the fluid from the high-pressure fluid region 30 being decelerated and then entering the annular air gap 13.

[0030] Specifically, a third through hole 113 is provided in the rotating shaft 112 and penetrates the rotating shaft 112 axially. Part of the fluid in the high-pressure fluid area 30 (specifically the receiving chamber 250 ) is suitable for flowing axially downward through the third through hole 113 to the bottom of the rotating shaft 112 and then flowing radially outward, and then flowing axially upward to decelerate and pass through the annular air gap 13 to cool the rotor 11.

[0031] In this embodiment, the motor 10 further includes a first bearing 114 and a second bearing 115 sleeved on the rotating shaft 112. The first bearing 114 and the second bearing 115 are respectively located at the axial ends of the rotor core 110. In this embodiment, the first bearing 114 and the second bearing 115 serve as bushings. The first bearing 114 maintains a first gap 116 with the rotating shaft 112 and is tightly fitted with the inner cylinder 121 of the stator housing 120. The second bearing 115 maintains a second gap 117 with the rotating shaft 112 and is tightly fitted with the inner cylinder 121 of the stator housing 120.

[0032] When the fluid pump of this embodiment is in use, the fluid enters the liquid inlet chamber 221 from the liquid inlet pipe 222, then enters the receiving chamber 250 through the first through hole 212, the radial flow channel 125, and the liquid inlet 231, and is driven by the impeller 24 to become a high-pressure fluid. At this time, most of the fluid flows out to the liquid outlet chamber 254 through the liquid outlet 251 and is discharged from the liquid outlet pipe 216. However, a small amount of fluid in the receiving chamber 250 flows axially downward through the third through hole 113 of the rotating shaft 112 to the bottom of the rotating shaft 112 and then flows radially outward, then flows axially upward through the first gap 116 to decelerate, then enters the annular air gap 13 to cool the rotor 11 of the motor, and then flows back to the annular chamber 41 (specifically the radial flow channel 125) through the second gap 117, and enters the receiving chamber 250 through the liquid inlet 231, then flows out to the liquid outlet chamber 254 through the liquid outlet 251, and finally is discharged from the liquid outlet pipe 216.

[0033] The fluid pump of the above embodiment is preferably suitable for cooling an electric vehicle charging pile, in particular for cooling the cable of the electric vehicle charging pile. Of course, in other embodiments, the fluid pump can also be used to cool other objects.

[0034] The above description is only a preferred specific embodiment of the present invention. The scope of protection of the present invention is not limited to the embodiments listed above. Any simple changes or equivalent replacements of the technical solutions that can be obviously obtained by any technician familiar with this technical field within the technical scope disclosed in the present invention fall within the scope of protection of the present invention.

Claims

1. A fluid pump, comprising a motor and a pump head, characterized in that, The fluid pump includes a high-pressure fluid region generated by the pump head and a low-pressure fluid region surrounding the high-pressure fluid region. The fluid is adapted to be discharged from the low-pressure fluid region via the high-pressure fluid region, and the rotor of the motor is cooled by the low-pressure fluid within the low-pressure fluid region.

2. The fluid pump according to claim 1, wherein, The pump head includes a relief valve located between the high-pressure fluid region and the low-pressure fluid region. When the fluid pressure in the high-pressure fluid region is greater than the rated value, the relief valve opens, and part of the fluid flows from the high-pressure fluid region into the low-pressure fluid region.

3. The fluid pump according to claim 1, characterized in that, The low-pressure fluid region includes an annular cavity surrounding the high-pressure fluid region and an annular air gap between the stator and the rotor of the motor. The annular air gap is located at one axial end of the annular cavity and communicates with the annular cavity.

4. The fluid pump according to claim 3, characterized in that, The inlet of the high-pressure fluid region is axially adjacent to the annular air gap between the stator and the rotor of the motor, and the outlet of the high-pressure fluid region is axially away from the annular air gap between the stator and the rotor of the motor.

5. The fluid pump according to claim 3, characterized in that, The fluid is adapted to enter the annular air gap between the stator and the rotor of the motor from the annular cavity to cool the rotor of the motor, and then flow back to the annular cavity and be discharged via the high-pressure fluid region.

6. The fluid pump according to claim 3, characterized in that, Part of the fluid in the high-pressure fluid region decelerates and then enters the annular air gap between the stator and the rotor of the motor to cool the rotor of the motor, and then flows back to the annular cavity and is discharged via the high-pressure fluid region.

7. The fluid pump according to claim 6, wherein A through hole axially penetrating through itself is provided in the rotating shaft of the motor. Part of the fluid in the high-pressure fluid region is adapted to flow axially downward through the through hole to the lower side of the rotating shaft and then radially outward, and then flow axially upward to decelerate and pass through the annular air gap between the stator and the rotor of the motor to cool the rotor of the motor.

8. The fluid pump according to claim 7, wherein The motor further includes a first bearing and a second bearing sleeved on the rotating shaft. A first gap is maintained between the first bearing and the rotating shaft, and a second gap is maintained between the second bearing and the rotating shaft. The fluid from the through hole in the rotating shaft is adapted to flow axially upward through the first gap to decelerate and pass through the annular air gap between the stator and the rotor of the motor to cool the rotor of the motor, and then flow back to the annular cavity through the second gap.

9. The fluid pump according to claim 3, characterized in that, The high-pressure fluid region is surrounded by the annular cavity of the low-pressure fluid region both circumferentially and axially.

10. Use of the fluid pump according to any one of claims 1 to 9 for cooling an electric vehicle charging pile.

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