Impeller for hydrogen circulating pump and hydrogen circulating pump

Abstract

The utility model relates to an impeller for a hydrogen circulating pump and the hydrogen circulating pump. The impeller comprises a hub, a rotor and a rotor, wherein the hub is used for being mounted on a motor shaft of the hydrogen circulating pump so as to be driven to rotate through rotation of the motor shaft; the blades extend from the hub in the radial direction of the impeller and are uniformly distributed in the circumferential direction of the impeller; each blade is divided into two halves by an imaginary central plane extending perpendicular to the axis of rotation of the impeller, a first half and a second half, the line of intersection of the first and second halves on said imaginary central plane defining a ridge, the first and second halves being inclined from the ridge toward the same inner side at an angle, the first half part and the second half part define two impeller channels which are located on the two sides of the imaginary center plane respectively and used for fluid flowing when the impeller is matched with a pump shell of the hydrogen circulating pump. According to the impeller, the open design with the two channels is provided, on one hand, water gathering at the bottom of the impeller is avoided, and on the other hand, the fluid flow rate of the pump is increased.

Description

Technical Field

[0001] The present application relates to fuel cell technology, and in particular to an impeller in a hydrogen circulation pump for a fuel cell system. Background Art

[0002] The hydrogen circulation pump is used to circulate hydrogen at the anode end of the hydrogen fuel cell. Its function is to pressurize and transport the unreacted hydrogen at the outlet of the fuel cell stack to the inlet of the fuel cell stack for recovery, so as to fully reuse the hydrogen. Usually, the hydrogen circulation pump has a motor and a pump head. The motor is associated with the impeller in the pump head through the motor shaft, so that the rotation of the motor shaft drives the impeller to rotate, thereby circulating the hydrogen.

[0003] In the current anode loop of the fuel cell engine, liquid water is an inevitable medium based on the reaction process of the fuel cell. The prior art hydrogen circulation pump generally uses a single-channel impeller, whose blade shape is semicircular, and the tail end of the blade is fixed by an end plate, and a semicircular flow channel for gas transportation is formed between the semicircular blade and the pump housing. In this way, due to the limitation of this semicircular single gas flow channel, water will continue to accumulate at the bottom of the impeller. When the vehicle is in a low temperature environment, the water accumulated at the bottom of the impeller is easy to freeze, so that the impeller cannot rotate due to the small gap between the impeller and the pump housing, resulting in the failure of the start-up of the hydrogen circulation pump. In addition, this single-channel impeller has only one gas flow channel, and the gas flow rate that can be provided is limited, which often cannot meet production requirements.

[0004] Therefore, it is necessary to provide an impeller structure that can effectively increase the gas flow rate while preventing the hydrogen circulation pump from being unable to start normally due to water accumulating and then freezing between the bottom of the impeller and the pump housing. Utility Model Content

[0005] The present application aims to provide an impeller structure which can effectively increase the gas flow rate while preventing ice from forming at low temperatures due to water accumulation between the bottom of the impeller and the pump housing.

[0006] To achieve the above-mentioned purpose, the present application provides an impeller for a hydrogen circulation pump, the impeller comprising: a hub for being mounted on the motor shaft of the hydrogen circulation pump so as to be driven to rotate by the rotation of the motor shaft; a plurality of blades extending from the hub along the radial direction of the impeller and evenly distributed along the circumferential direction of the impeller; each of the blades is divided into two halves by an imaginary center plane extending perpendicular to the rotation axis of the impeller, namely a first half and a second half, the intersection of the first half and the second half on the imaginary center plane defines a ridge, the first half and the second half are inclined at a certain angle from the ridge toward the same side, and the first half and the second half define two impeller channels for fluid flow, which are respectively located on both sides of the imaginary center plane when the impeller is matched with the pump housing of the hydrogen circulation pump.

[0007] Optionally, the first half and the second half of the blade are arranged symmetrically about the imaginary central plane.

[0008] Optionally, the ridge is in a straight line shape, or alternatively, the ridge is in a curved line shape.

[0009] Each of the blades is bent in the same direction and at the same angle along the circumferential direction of the impeller.

[0010] Optionally, the distal end of the blade is a free end with an open structure.

[0011] Optionally, it also includes reinforcing ribs extending from the hub along the radial direction of the impeller between two adjacent blades to strengthen the blades.

[0012] Optionally, the thickness of the reinforcing rib gradually decreases from the hub to the distal end of the reinforcing rib.

[0013] The present application also relates to a hydrogen circulation pump, which comprises: an impeller as described above; and a pump casing for accommodating the impeller, wherein the impeller is rotatably mounted in the pump casing, a portion of the outer contour of the pump casing corresponds to the shape of the distal end of the blade, and the pump casing cooperates with the first half and the second half of the impeller to define the two impeller channels.

[0014] Optionally, the pump housing is divided into a first housing and a second housing along the imaginary central plane, and the first housing and the second housing respectively accommodate a first half and a second half of the blade.

[0015] Optionally, at the intersection of the first shell and the second shell, at a position corresponding to the distal end of the blade and the ridge, a guide member is provided which protrudes toward the distal end of the blade for guiding the fluid.

[0016] According to the present application, by changing the shape and structure of the impeller, the impeller can provide a dual-channel structure for gas flow, so that moisture will not accumulate at the bottom of the shell to avoid freezing at low temperatures, and the gas flow rate is effectively increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other aspects of the present application will be more clearly understood in conjunction with the accompanying drawings. It should be noted that the drawings are only schematic and are not drawn to scale. In the drawings:

[0018] Figure 1 Schematically shows a partially cutaway perspective view of an impeller for a hydrogen circulation pump according to the present application;

[0019] Figure 2 Schematically shows Figure 1 A cross-sectional view of the impeller when it is assembled in the pump housing of the hydrogen circulation pump;

[0020] Figure 3 A perspective view schematically shows an impeller for a hydrogen circulation pump according to the present application. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present application are described in detail below in conjunction with examples. It should be understood by those skilled in the art that these embodiments are not intended to limit the present application in any way, and the features in the various embodiments may be combined with each other. In different drawings, the same components are represented by the same reference numerals, and for the sake of brevity, some components are omitted, but this does not mean that other components are excluded. It should be understood that the size, proportional relationship and number of components of the various components in the drawings are not intended to limit the present application.

[0022] As mentioned above, the impeller in the existing hydrogen circulation pump usually includes semicircular blades, and the distal ends of the blades are fixed together by outer ring end plates. Therefore, water in the anode loop can easily accumulate at the bottom of the impeller. If the vehicle is in a low temperature environment, especially after the engine is shut down in winter, for example, when the ambient test temperature is below 0°C, the water retained at the bottom of the impeller of the hydrogen circulation pump may be frozen, thereby causing the hydrogen circulation pump to fail to start. In addition, the semicircular blades limit the impeller to only provide one impeller channel for gas flow.

[0023] Figure 1 A partial cutaway view of an impeller for a hydrogen circulation pump of the present application is shown, Figure 3A perspective view of the impeller for a hydrogen circulation pump of the present application is shown. As shown in the figure, the impeller of the present application adopts an open impeller design. The impeller has a hub 1 and a plurality of blades 2 extending radially outward from the hub 1 along the impeller. The hub 1 and the blades 2 can be designed as an integral part, for example, they are made of one material. When metal materials are used, they can be integrally formed using a mold. When materials such as resins are used, they can be made by injection molding, or they can be made by insert molding using metal materials and resin materials.

[0024] Optionally, the hub 1 and the blades 2 may also be made into separate components, and then connected using means known in the prior art such as welding, thermal fusion, etc.

[0025] In the present application, each blade 2 may extend outwardly along the radial direction of the impeller and be evenly distributed along the circumferential direction of the impeller. The number of blades 2 may be set according to actual needs and is not specifically limited. The blades 2 may have a shape that is symmetrical about an imaginary central plane 21 extending perpendicular to the rotation axis of the impeller, that is, the imaginary central plane 21 divides each blade into two symmetrical halves, such as a first half 22 and a second half 23, and the portion where the first half 22 and the second half 23 intersect on the imaginary central plane 21 forms a curve that may also be referred to as a ridge 25, such as Figure 3 As shown in FIG. 1 , the first half 22 and the second half 23 of each blade intersect at the ridge 25, and the first half 22 and the second half 23 are bent toward the same side from the ridge 25, for example, Figure 1 The first half 22 and the second half 23 of the lowermost blade 2 are inclined inward from the paper surface from the ridge 25, Figure 1 The first half 22 and the second half 23 of the uppermost blade 2 are inclined outward from the paper surface from the ridge 25, so that the first half 22 and the second half 23 of each blade 2 have a shape similar to a roof ridge.

[0026] Of course, the first half 22 and the second half 23 may also be arranged asymmetrically with respect to the imaginary center plane 21 .

[0027] Since the first half 22 and the second half 23 intersect along the imaginary center plane 21 to form a curved ridge 25, the entire blade group 2 is curved in the same direction along the circumferential direction when viewed from the radial direction of the impeller. Figure 1 Observe from the left and Figure 3 When viewed from the upper middle side, the tail ends or distal ends of all blades 2 are bent in the clockwise direction. Of course, the bending direction may be the opposite, that is, bent in the counterclockwise direction when viewed from the same viewing direction, depending on the direction in which the impeller is to be installed in the pump housing in the hydrogen circulation pump.

[0028] Although Figure 1 and 3 The ridge 25 shown in the figure is in the shape of a curve, but the ridge 25 can also be in a straight line, so that the entire group of blades 3 will not be bent in the clockwise or counterclockwise direction as mentioned above, but all blades 3 will extend radially along the radial direction of the impeller and be evenly distributed, but the first half 22 and the second half 23 of each blade are still bent at an angle toward the same side.

[0029] As described above, each blade 2 is formed by protruding and extending from the hub 1 along the radial direction of the impeller. However, the thickness of the blade 2 is usually thin and easy to deform. In order to ensure that the blade 2 can be stable and not deformed and damaged during the rotation process, a reinforcing rib 24 is further provided between each blade 2. Figure 3 As shown, the reinforcing ribs 24 may extend from the hub 1 and extend between adjacent blades 2, so that the hub 1, the blades 2 and the reinforcing ribs 24 are integrated. When the impeller is made of polyester material, the reinforcing ribs 24 may be integrally molded during the molding of the impeller. When the impeller is made of metal material, the reinforcing ribs 24 may be integrally formed with the hub 1 and the blades 2, such as by casting, etc., or may be formed separately, and the various parts may be connected together, such as by welding, etc.

[0030] The reinforcing rib 24 may be in the shape of a plate with uniform thickness, or in the shape of a wedge that gradually becomes thinner from the wheel hub 1 toward the tip or distal end of the reinforcing rib 24 .

[0031] The length of the reinforcing rib 24 along the radial direction of the impeller can be set as needed, for example, it can be 1 / 4-1 / 2 of the length of the blade 2, etc. It can be set according to specific design requirements, but is not limited thereto.

[0032] Although it is described above that the two halves of the impeller blade 2 are symmetrical about the imaginary center plane 21, the present application is not limited thereto, and on the contrary, the first half 22 and the second half 23 may have an asymmetrical shape, for example, the area of ​​the first half 22 may be larger than the area of ​​the second half, or vice versa.

[0033] The first half portion 22 and the second half portion 23 may both be, for example, substantially rectangular in shape, or may be other shapes, such as a trapezoid, etc., but are not limited thereto.

[0034] Although the first half 22 and the second half 23 are inclined from the ridge 25 toward the same side at the same angle as described above, the present application is not limited thereto, and the first half 22 and the second half 23 may be inclined from the ridge at the same angle or at different angles.

[0035] Figure 2, a cross-sectional view along the radial direction of the impeller is shown in the state where the impeller is assembled with the pump housing 3 of the hydrogen circulation pump. Corresponding to the blades 2 of the impeller, the pump housing 3 also includes two housing halves, namely the first housing 32 and the second housing 33. The overall cross-sectional shape of the pump housing 3 along the radial direction of the impeller is roughly double-cylindrical, namely the first housing 32 and the second housing 33 are respectively a part of the cylinder, the parts of the first housing 32 and the second housing 33 that accommodate the blades 2 correspond to the shape of the tail of the blades 2, and the remaining parts are formed into spaces 34 and 35 for the flow of the pumped fluid, such as hydrogen. Figure 3 A first space 34 and a second space 35 are shown in FIG.

[0036] exist Figure 3 The first space 34 and the second space 35 are shown as two spaces with semicircular cross-sections. However, according to actual needs, the pump housing 3 can be designed to be non-cylindrical, such as an elliptical shape. Accordingly, the first space 34 and the second space 35 can be other shapes, such as a semi-elliptical shape.

[0037] Between the first space 34 and the second space 35 of the pump housing 3, on both sides of the imaginary central plane 21, at positions corresponding to the first half 22 and the second half 23 of the blade 2, two impeller channels for fluid circulation, namely the first channel 36 and the second channel 37, are formed. The first channel 36 and the second channel 37 are generated by the first half 22 and the second half 23 of the blade 2 rotating in the pump housing 3 to drive the fluid flow, that is, during the rotation of the blade 2, the pumped fluid, such as hydrogen, will be guided by the first half 22 and the second half 23 of the blade 2, pass through the first channel 36 and the second channel 37, and then enter the first space 34 and the second space 35, and finally be transported from the pump outlet to where it is needed.

[0038] exist Figure 1 and 3 The distal ends of the blades 2 of the impeller shown in the figure are not provided with peripheral end plates to connect and fix the blades 2 like the impeller with semicircular blades in the prior art. On the contrary, the distal ends of the blades 2 in the present application are open, that is, the distal ends of the blades 2 are free ends and are not connected to any other parts. In this way, no water will be gathered at the bottom of the impeller at the distal ends of the blades 2, thereby avoiding the phenomenon in the prior art that water gathers at the bottom of the impeller at the distal ends of the blades 2, thereby causing the impeller to freeze at low temperatures, which will make the start-up of the hydrogen circulation pump fail.

[0039] In the case of such an open distal end design of the blade 2 in the present application, the pump housing 3 of the hydrogen circulation pump in the present application can be designed to be at the connection between the first housing 32 and the second housing 33, at a position corresponding to the distal end of the blade 2 and the ridge 25, a guide member 31 protruding from the pump housing 3 toward the blade 2 is provided, which serves as a fluid baffle or guide element for guiding the smooth flow of the fluid along the radial direction of the impeller.

[0040] It is described above that the first half 22 and the second half 23 of the blade 2 extend from the ridge 25 toward the same side at a certain angle, and the angle can be specifically adjusted according to the design requirements of the hydrogen circulation pump. In addition, the first half 22 and the second half 23 can also be set to extend from the ridge 25 along the axial direction of the impeller, that is, not extending at an angle, or the inclination angle is set to 0. When the inclination angle is 0, the ridge 25 can be a straight line or a curve. When the ridge 25 is a straight line, the first half 22 and the second half 23 of the blade become a flat plate extending on a blade plane. When the ridge 25 is a curve, the blade 2 is a plate-like shape that is bent only in the circumferential direction.

[0041] There is no clear limitation on the thickness of the blade 2 in the present application, as long as the mechanical strength requirement of the blade 2 is met, that is, the blade 2 does not deform or break during the rotation of the impeller.

[0042] Thus, in the present application, the impeller blade 2 is set to have two halves, and each half has a specific angle, so that when the impeller cooperates with the pump housing 3, a double impeller channel for fluid flow, namely the first channel 36 and the second channel 37, is formed, and then the outer peripheral end of the impeller blade 2 can be designed as an open structure, so that no water will accumulate at the bottom of the impeller, which can avoid the hydrogen circulation pump from freezing due to the accumulated water at low temperatures, thereby ensuring the normal start-up of the hydrogen circulation pump at low temperatures. Moreover, since the impeller adopts the above-mentioned double impeller channel structure design, the fluid flow rate that the impeller can provide is twice the flow rate of the existing single-channel design of semicircular blades, further increasing the working efficiency of the entire hydrogen circulation pump.

[0043] The present application has been described in detail above in conjunction with specific embodiments. Obviously, the above description and the embodiments shown in the accompanying drawings should be understood as exemplary and do not constitute a limitation to the present application. For those skilled in the art, various modifications or changes can be made to the present application without departing from the spirit of the present application, and these modifications or changes do not depart from the scope of the present application.

Claims

1. An impeller for a hydrogen circulation pump, characterized in that: The impeller comprises: A wheel hub (1) for being mounted on the motor shaft of the hydrogen circulation pump so as to be driven to rotate by the rotation of the motor shaft; A plurality of blades (2) extending from the hub (1) in the radial direction of the impeller and evenly distributed in the circumferential direction of the impeller; Each of the blades (2) is divided into two halves, namely a first half (22) and a second half (23), by an imaginary center plane (21) extending perpendicularly to the rotation axis of the impeller. The intersection of the first half (22) and the second half (23) on the imaginary center plane (21) defines a ridge (25). The first half (22) and the second half (23) are inclined at a certain angle toward the same side from the ridge (25). When the impeller is matched with the pump housing of the hydrogen circulation pump, the first half (22) and the second half (23) define two impeller channels (36, 37) for fluid flow, which are respectively located on both sides of the imaginary center plane (21).

2. The impeller according to claim 1, characterized in that: The first half (22) and the second half (23) of the blade are arranged symmetrically about the imaginary center plane (21).

3. The impeller according to claim 1, characterized in that: The ridge (25) is in a straight line shape.

4. The impeller according to claim 1, characterized in that: The ridge (25) is in a curved shape.

5. The impeller according to claim 4, characterized in that: Each blade (2) is bent in the same direction and at the same angle along the circumferential direction of the impeller.

6. The impeller according to any one of claims 1 to 5, characterized in that: The distal end of the blade (2) is a free end with an open structure.

7. The impeller according to claim 1, characterized in that It also includes a reinforcing rib (24) extending from the hub (1) along the impeller radial direction between two adjacent blades (2) to reinforce the blades (2).

8. The impeller according to claim 7, characterized in that The thickness of the reinforcing rib (24) gradually decreases from the hub (1) to the distal end of the reinforcing rib.

9. A hydrogen circulation pump, characterized in that: The hydrogen circulation pump comprises: An impeller according to any one of claims 1 to 8; and A pump housing (3) for accommodating the impeller, wherein the impeller is rotatably mounted in the pump housing (3), a portion of the outer contour of the pump housing (3) corresponds to the shape of the distal end of the blade (2), and the pump housing (3) cooperates with the first half (22) and the second half (23) of the impeller to define the two impeller channels (36, 37).

10. The hydrogen circulation pump according to claim 9, characterized in that: The pump housing (3) is divided into a first housing (32) and a second housing (33) along the imaginary central plane (21), wherein the first housing (32) and the second housing (33) respectively accommodate a first half (22) and a second half (23) of the blade (2).

11. The hydrogen circulation pump according to claim 10, characterized in that: At the intersection of the first shell (32) and the second shell (33), at a position corresponding to the distal end of the blade (2) and the ridge (25), a guide (31) is provided which protrudes toward the distal end of the blade (2) for guiding fluid.

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