A sealed drainage structure for a fuel cell hydrogen circulation pump

Abstract

The present invention belongs to the technical field of hydrogen fuel automobile parts and components. A water-spinning trough (9) is arranged at the joint of the impeller root (16) and the impeller body (17) of the impeller (7) of the fuel cell hydrogen circulation pump sealing and drainage structure, and a bell mouth (10) is arranged at the water-spinning trough (9) facing the pump body (1). The piston ring (12) in the mounting groove (18) of the impeller root (16) fits the inner wall of the sealing ring cavity (19) of the pump body (1), and a drainage port (15) is arranged at the cover plate (2) near the bottom (20) of the air cavity. The fuel cell hydrogen circulation pump sealing and drainage structure of the present invention can block water from entering the bearing and the motor during the operation of the hydrogen circulation pump, thereby preventing the bearing and the motor from rusting and being damaged. At the same time, the blocked water can be discharged from the hydrogen circulation pump, thereby preventing the hydrogen circulation pump from freezing due to water accumulation at low temperature, reliably protecting the circulation pump, and improving the service life and working reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen fuel automobile parts, and more specifically, relates to a sealing and drainage structure of a fuel cell hydrogen circulation pump. Background Art

[0002] Fuel cells generate electricity through the electrochemical reaction between hydrogen and oxygen in the air. It is a process of converting chemical energy into electrical energy, accompanied by the production of water. In practical applications, the supply of hydrogen is generally greater than the demand for electrochemical reactions. In order to save energy and prevent hydrogen from being directly discharged into the air to cause environmental pollution and the risk of explosion, this part of hydrogen needs to be recycled and reused through a hydrogen circulation pump. Since the recycled hydrogen contains a large amount of water vapor and even liquid water, in the working process of the hydrogen circulation pump, water vapor and liquid water will gather in the air cavity on the one hand. In a low temperature environment, water condenses into ice, which will hinder the rotation of the impeller, causing a relatively large power loss under the cold start of the hydrogen circulation pump, and even causing it to fail to start; on the other hand, water will pass through the air seal into the bearing and the motor, causing rust and damage to the bearing and the motor. In order to solve this technical problem, some products use ceramic bearings to prevent rust, while others use motor waterproof coatings to prevent rust. Regardless of the method, passive waterproofing is the main method, which does not fundamentally prevent the entry of water and is costly. Summary of the invention

[0003] The technical problem to be solved by the present invention is: in view of the deficiencies in the prior art, a fuel cell hydrogen circulation pump sealing and drainage structure with a simple structure is provided, which can block moisture from entering the bearings and the inside of the motor during the operation of the hydrogen circulation pump to prevent the bearings and the motor from rusting and being damaged, and can also discharge the blocked moisture from the hydrogen circulation pump to prevent the hydrogen circulation pump from being stuck due to water accumulation and freezing at low temperatures, thereby reliably protecting the circulation pump and improving the service life and working reliability.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is:

[0005] The present invention is a sealing and drainage structure for a fuel cell hydrogen circulation pump. An air cavity is formed between one side of a pump body of the circulation pump and a cover plate. A motor is installed on the other side of the pump body. An impeller is installed at one end of a motor rotor shaft of the motor extending into the air cavity. The impeller 7 includes an impeller root protruding toward the motor. A recessed water-shedding trough is arranged at the joint between the impeller root and the impeller body. A protruding bell-mouth portion is arranged at the water-shedding trough opposite to the pump body. The extended line of the groove edge of the water-shedding trough intersects with the bell-mouth portion. An installation groove is arranged along the impeller root at the impeller root. A piston ring is installed in the installation groove. The piston ring fits the inner wall of the sealing ring cavity of the pump body. A drainage port is arranged at the cover plate near the bottom of the air cavity.

[0006] An axial gap is provided between the piston ring side surface and the mounting groove side surface of the fuel cell hydrogen circulation pump sealing and drainage structure, and a radial gap is provided between the piston ring bottom surface and the mounting groove bottom surface.

[0007] An air inlet and an air outlet are arranged on the cover plate.

[0008] The outer surface of the piston ring protrudes from the root surface of the impeller.

[0009] The impeller is configured to be a structure capable of rotating and transporting hydrogen under the drive of the motor rotor shaft of the motor.

[0010] An air seal is also installed on the motor rotor shaft. The air seal is located on one side of the impeller and fits the inner wall of the sealing ring cavity of the pump body.

[0011] A bearing is also installed on the motor rotor shaft, and the bearing fits the inner wall of the sealing ring cavity of the pump body.

[0012] The gas seal side surface is simultaneously pressed against and limited on a first limit platform protruding from the inner wall of the sealing ring cavity; the bearing side surface is simultaneously pressed against and limited on a second limit platform protruding from the inner wall of the sealing ring cavity.

[0013] The impeller is interference fit with the motor rotor shaft.

[0014] Two or more drain outlets are provided.

[0015] The technical solution of the present invention is adopted, and the working principle and beneficial effects are as follows:

[0016] In the sealing and drainage structure of the fuel cell hydrogen circulation pump described in the present invention, the impeller is installed on the motor rotor shaft through an interference fit. During the operation of the hydrogen circulation pump, the impeller rotates and transports hydrogen under the drive of the motor. Since the fuel cell generates electricity through the electrochemical reaction of hydrogen and oxygen, water is also generated. After the water is mixed with the excess hydrogen, it enters the air cavity through the air inlet of the hydrogen circulation pump. On the one hand, it will gather in the air cavity. In a low temperature environment, the water condenses into ice, which will hinder the rotation of the impeller, causing the hydrogen circulation pump to lose power during cold start at the least, and even fail to start at the worst. On the other hand, water will pass through the air seal and enter the inside of the bearing and the motor, causing the bearing and the inside of the motor to rust and damage. The above technical problems, the present invention realizes the waterproof function from three aspects: first, a recessed water-spurting groove is set at the joint of the impeller root and the impeller body. Under the centrifugal force of the impeller water-spurting groove, most of the liquid water is thrown to the bell mouth of the pump body, and then the liquid water thrown to the bell mouth will flow into the bottom of the air cavity along the end face of the pump body; in addition, a part of the liquid water flowing to the motor side under the pressure of the air cavity flows back to the bottom of the air cavity under the blocking effect of the piston ring; finally, all the liquid water accumulated at the bottom of the air cavity is discharged from the hydrogen circulation pump through the drain port under the action of gravity. The drain port is used in combination with the electromagnetic valve, and the electromagnetic valve can control the opening and closing of the drain port as needed, and the timed drainage function can be realized by electric control. Two or more drain ports can be set, and the pump body and the motor are designed with uniformly distributed bolts. In this way, when the cover plate is connected to the pump body, the relative position of the two can be changed, and it is always ensured that there is a drain port at the lowest position. In this way, the installation direction of the air inlet is adjustable, and the drain port at the lowest point of the bottom of the air cavity has a drainage function, which comprehensively solves the existing problems. The fuel cell hydrogen circulation pump sealing and drainage structure of the present invention has a simple structure and can block moisture from entering the bearings and the inside of the motor during the operation of the hydrogen circulation pump to prevent the bearings and the motor from rusting and being damaged. At the same time, it can discharge the blocked moisture from the hydrogen circulation pump to prevent the hydrogen circulation pump from being stuck due to water accumulation and freezing at low temperatures, thereby reliably protecting the circulation pump and improving its service life and working reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following is a brief description of the contents and symbols in the drawings of this specification:

[0018] Figure 1 This is a schematic structural diagram of the sealing and drainage structure of the fuel cell hydrogen circulation pump according to the present invention;

[0019] Figure 2 It is a schematic diagram of the internal cross-sectional structure of the sealing and drainage structure of the fuel cell hydrogen circulation pump of the present invention;

[0020] Figure 3 for Figure 2 A schematic diagram of a partial cross-sectional structure of the sealing and drainage structure of the fuel cell hydrogen circulation pump;

[0021] The marks in the attached drawings are respectively: 1, pump body; 2, cover plate; 3, air cavity; 4, motor; 5, air inlet; 6, air outlet; 7, impeller; 8, motor rotor shaft; 9, water trough; 10, bell mouth; 11, groove edge; 12, piston ring; 13, bearing; 14, air seal; 15, drain outlet; 16, impeller root; 17, impeller body; 18, mounting groove; 19, sealing ring cavity; 20, bottom of air cavity; 21, first limit platform; 22, second limit platform; 23, groove edge extension line; A, axial clearance; B, radial clearance. DETAILED DESCRIPTION

[0022] The following is a further detailed description of the specific implementation of the present invention, such as the shape, structure, mutual position and connection relationship between the various components involved, the function and working principle of each part, etc., through the description of the embodiments with reference to the accompanying drawings:

[0023] As attached Figure 1 -Attached Figure 3As shown, the present invention is a sealing and drainage structure of a fuel cell hydrogen circulation pump. An air cavity 3 is formed between one side of the pump body 1 of the circulation pump and the cover plate 2. A motor 4 is installed on the other side of the pump body 1. An impeller 7 is installed at one end of the motor rotor shaft 8 of the motor 4 extending into the air cavity 3. The impeller 7 includes an impeller root 16 protruding toward the motor 4. A recessed water-spinning groove 9 is provided at the joint of the impeller root 16 and the impeller body 17. A protruding bell-mouth portion 10 is provided at the position of the water-spinning groove 9 facing the pump body 1. The groove edge extension line 23 of the water-spinning groove intersects with the bell-mouth portion. An installation groove 18 is provided along the impeller root 16. A piston ring 12 is installed in the installation groove 18. The piston ring 12 fits the inner wall of the sealing ring cavity 19 of the pump body 1. A drainage port 15 is provided at the cover plate 2 near the bottom 20 of the air cavity. The above structure proposes an improved technical solution to address the deficiencies in the prior art. The impeller 7 is installed on the motor rotor shaft 8 by interference fit. During the operation of the hydrogen circulation pump, the impeller 7 is driven by the motor 4 to rotate and transport hydrogen. Since the fuel cell generates electricity through the electrochemical reaction of hydrogen and oxygen, it will also produce water. After the water is mixed with the excess hydrogen, it enters the air cavity 3 through the hydrogen circulation pump inlet 5. On the one hand, it will gather in the air cavity 3. In a low temperature environment, water condenses into ice, which will hinder the rotation of the impeller 7. At the least, it will cause a large power loss during the cold start of the hydrogen circulation pump, and at worst, it will cause it to fail to start. On the other hand, water will pass through the air seal 14 and enter the inside of the bearing 13 and the motor 4, causing the bearing 13 and the motor 4 to rust and be damaged. In view of the above technical problems, the present invention has three aspects: The waterproof function is realized in the following aspects: first, a recessed water-spinning groove 9 is set at the joint of the impeller root 16 and the impeller body 17. Under the centrifugal force of the impeller water-spinning groove 9, most of the liquid water is thrown to the bell mouth 10 of the pump body, and then the liquid water thrown to the bell mouth will flow into the bottom 20 of the air cavity along the end face of the pump body; in addition, a part of the liquid water flowing to the motor side under the pressure of the air cavity will flow back to the bottom 20 of the air cavity under the blocking effect of the piston ring 12; finally, all the liquid water accumulated at the bottom 20 of the air cavity is discharged from the hydrogen circulation pump through the drain port 15 under the action of gravity. The drain port 15 is used in combination with the electromagnetic valve. The electromagnetic valve can control the opening and closing of the drain port as needed, and the timed drainage function can be realized by electric control. Two or more drain ports 15 can be set, and the pump body and the motor are designed with uniformly distributed bolts to realize the adjustable installation direction of the air inlet 5. Obviously, the drain port 15 located at the lowest point of the air cavity 3 has a drainage function, which comprehensively solves the existing problems. The fuel cell hydrogen circulation pump sealing and drainage structure of the present invention has a simple structure and can block moisture from entering the bearings and the inside of the motor during the operation of the hydrogen circulation pump to prevent the bearings and the motor from rusting and being damaged. At the same time, it can discharge the blocked moisture from the hydrogen circulation pump to prevent the hydrogen circulation pump from being stuck due to water accumulation and freezing at low temperatures, thereby reliably protecting the circulation pump and improving its service life and working reliability.

[0024] An axial gap A is provided between the side of the piston ring 12 and the side of the mounting groove 18 of the fuel cell hydrogen circulation pump sealing and drainage structure, and a radial gap B is provided between the bottom of the piston ring 12 and the bottom of the mounting groove 18. The axial gap is 0.01-0.03 mm, and the radial gap is 0.2-0.4 mm.

[0025] The axial clearance A is set to achieve a sealing effect through clearance fit and play a waterproof role. The radial clearance B is set to prevent the piston ring from contacting the bottom surface of the installation groove to avoid jamming.

[0026] The cover plate 2 is provided with an air inlet 5 and an air outlet 6. In the above structure, the air inlet is used for air intake and the air outlet is used for exhaust, which meets the working requirements of the entire hydrogen circulation pump.

[0027] The outer surface of the piston ring 12 protrudes from the surface of the impeller root 16. In the above structure, the outer surface of the piston ring 12 protrudes from the surface of the impeller root 16 and is arranged in close contact with the inner wall of the sealing ring cavity 19, thereby effectively blocking a part of the liquid water flowing to the motor side under the pressure of the air cavity, and the liquid water flows back to the bottom 20 of the air cavity under the blocking effect of the piston ring 12, and then drains the water.

[0028] The impeller 7 is configured to be a structure capable of rotating and transporting hydrogen under the drive of the motor rotor shaft 8 of the motor 4 .

[0029] An air seal 14 is also installed on the motor rotor shaft 8. The air seal 14 is located on one side of the impeller 7, and the air seal 14 fits the inner wall of the sealing ring cavity 19 of the pump body 1. A bearing 13 is also installed on the motor rotor shaft 8, and the bearing 13 fits the inner wall of the sealing ring cavity 19 of the pump body 1. The side of the air seal 14 is simultaneously pressed against a first limit platform 21 protruding from the inner wall of the sealing ring cavity 19; the side of the bearing 13 is simultaneously pressed against a second limit platform 22 protruding from the inner wall of the sealing ring cavity 19. In the above structure, the first limit platform 21 can reliably limit the axial position of the air seal 14, ensuring that the installation position is accurate and will not move easily. The second limit platform 22 can reliably limit the axial position of the bearing 13, ensuring that the installation position is accurate and will not move easily.

[0030] The impeller 7 and the motor rotor shaft 8 are interference fit.

[0031] The drain ports 15 are provided with two or more. The drain ports are sealed by plugs or connected to electromagnetic valves. In the above structure, the drain ports are provided along the cover plate near the edge, and the pump body and the motor are evenly bolted to realize the adjustable installation direction of the air inlet 5. No matter how the cover plate is connected to the pump body, there is always a drain port located at the lowest position. In this way, the drain port 15 located at the lowest point of the air cavity 3 obviously has the function of drainage. The electromagnetic valve controls the on and off of the drain port.

[0032] In the sealing and drainage structure of the fuel cell hydrogen circulation pump described in the present invention, the impeller is installed on the motor rotor shaft through an interference fit. During the operation of the hydrogen circulation pump, the impeller rotates and transports hydrogen under the drive of the motor. Since the fuel cell generates electricity through the electrochemical reaction of hydrogen and oxygen, water is also generated. After the water is mixed with the excess hydrogen, it enters the air cavity through the air inlet of the hydrogen circulation pump. On the one hand, it will gather in the air cavity. In a low temperature environment, the water condenses into ice, which will hinder the rotation of the impeller, causing the hydrogen circulation pump to lose power during cold start at the least, and even fail to start at the worst. On the other hand, water will pass through the air seal and enter the inside of the bearing and the motor, causing the bearing and the inside of the motor to rust and damage. The above technical problems, the present invention realizes the waterproof function from three aspects: first, a recessed water-spurting groove is set at the joint of the impeller root and the impeller body. Under the centrifugal force of the impeller water-spurting groove, most of the liquid water is thrown to the bell mouth of the pump body, and then the liquid water thrown to the bell mouth will flow into the bottom of the air cavity along the end face of the pump body; in addition, a part of the liquid water flowing to the motor side under the pressure of the air cavity flows back to the bottom of the air cavity under the blocking effect of the piston ring; finally, all the liquid water accumulated at the bottom of the air cavity is discharged from the hydrogen circulation pump through the drain port under the action of gravity. The drain port is used in combination with the electromagnetic valve, and the electromagnetic valve can control the opening and closing of the drain port as needed, and the timed drainage function can be realized by electric control. Two or more drain ports can be set, and the pump body and the motor are designed with uniformly distributed bolts. In this way, when the cover plate is connected to the pump body, the relative position of the two can be changed, and it is always ensured that there is a drain port at the lowest position. In this way, the installation direction of the air inlet is adjustable, and the drain port at the lowest point of the bottom of the air cavity has a drainage function, which comprehensively solves the existing problems. The fuel cell hydrogen circulation pump sealing and drainage structure of the present invention has a simple structure and can block moisture from entering the bearings and the inside of the motor during the operation of the hydrogen circulation pump to prevent the bearings and the motor from rusting and being damaged. At the same time, it can discharge the blocked moisture from the hydrogen circulation pump to prevent the hydrogen circulation pump from being stuck due to water accumulation and freezing at low temperatures, thereby reliably protecting the circulation pump and improving its service life and working reliability.

[0033] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A fuel cell hydrogen circulation pump sealing and drainage structure, characterized in that: An air cavity (3) is formed between one side of a pump body (1) and a cover plate (2) of a circulation pump, a motor (4) is installed on the other side of the pump body (1), an impeller (7) is installed at one end of a motor rotor shaft (8) of the motor (4) extending into the air cavity (3), the impeller (7) comprises an impeller root (16) protruding in the direction of the motor (4), a recessed water-shedding trough (9) is arranged at a junction of the impeller root (16) and an impeller body (17), a protruding bell-mouth portion (10) is arranged at a position of the water-shedding trough (9) facing the pump body (1), an extension line of the groove edge of the water-shedding trough (9) intersecting with the bell-mouth portion (10), an installation groove (18) is arranged along a circle of the impeller root (16) at the position of the impeller root (16), a piston ring (12) is installed in the installation groove (18), the piston ring (12) is in contact with the inner wall of a sealing ring cavity (19) of the pump body (1), and a drainage port (15) is arranged at a position of the cover plate (2) close to a bottom (20) of the air cavity; An axial gap (A) is provided between the side surface of the piston ring (12) and the side surface of the mounting groove (18) of the fuel cell hydrogen circulation pump sealing and drainage structure, and a radial gap (B) is provided between the bottom surface of the piston ring (12) and the bottom surface of the mounting groove (18); the axial gap (A) is provided to achieve a sealing effect through clearance fit and to play a waterproof role; the radial gap (B) is provided to prevent the piston ring from contacting the bottom surface of the mounting groove to avoid jamming; The outer surface of the piston ring (12) protrudes from the surface of the impeller root (16).

2. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 1, characterized in that: An air inlet (5) and an air outlet (6) are provided on the cover plate (2).

3. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 1 or 2, characterized in that: The impeller (7) is configured as a structure capable of rotating and transporting hydrogen under the drive of the motor rotor shaft (8) of the motor (4).

4. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 1 or 2, characterized in that: An air seal (14) is also installed on the motor rotor shaft (8). The air seal (14) is located on one side of the impeller (7). The air seal (14) fits against the inner wall of the sealing ring cavity (19) of the pump body (1).

5. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 4, characterized in that: A bearing (13) is also mounted on the motor rotor shaft (8), and the bearing (13) fits against the inner wall of the sealing ring cavity (19) of the pump body (1).

6. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 5, characterized in that: The side surface of the gas seal (14) is simultaneously abutted against a first limit platform (21) protruding from the inner wall of the sealing ring cavity (19) for position limiting; the side surface of the bearing (13) is simultaneously abutted against a second limit platform (22) protruding from the inner wall of the sealing ring cavity (19) for position limiting.

7. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 1 or 2, characterized in that: The impeller (7) and the motor rotor shaft (8) are interference fit.

8. The fuel cell hydrogen circulation pump sealing and drainage structure according to claim 1 or 2, characterized in that: Two or more drainage outlets (15) are provided.

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