Centrifugal fuel pump

Abstract

The invention discloses a centrifugal fuel pump and belongs to the field of aerospace. The centrifugal fuel pump comprises a front cover, a shell, an impeller, a boss nut, a prime motor transmission shaft, a rear cover, a screw and a locking nut. A flat key connection mode of the impeller and the transmission shaft is omitted, the machining manufacturability and the assembly manufacturability of the impeller and the motor transmission shaft can be improved, and the product maintainability is improved; the dynamic balance grade of the impeller and the motor transmission shaft during working can be improved, vibration and noise caused by uneven mass distribution are reduced, the performance of the electric fuel pump is improved, and the service life of the electric fuel pump is prolonged.

Description

Technical Field

[0001] This invention patent belongs to the field of aerospace, and specifically relates to a centrifugal fuel pump. Background Art

[0002] Centrifugal fuel pumps have the characteristics of large flow rate, simple structure, and strong anti-pollution ability, and are widely used in aviation fuel systems.

[0003] The impeller of a conventional centrifugal fuel pump is connected to the motor shaft through a flat key, and then axially positioned using a lock nut. In this connection method, when installing, it is necessary to ensure both the clearance between the impeller and the drive shaft and the installation and fitting dimensions of the flat key. When disassembling, it is extremely easy to cause the impeller to jam with the motor shaft, and the assembly processability is poor; it is difficult to meet the dynamic balance levels of the drive shaft and the impeller, affecting the working reliability and life of the electric fuel pump.

[0004] The present invention proposes a new connection method between the impeller of a centrifugal fuel pump and the motor shaft, which can improve the processability, meet the dynamic balance requirements of the impeller, and improve the working performance, reliability, and life of the centrifugal fuel pump. Summary of the Invention

[0005] Aiming at the above problems, the purpose of this invention patent is to provide a centrifugal fuel pump, which improves the processing technology, assembly technology, reliability, and service life of the centrifugal fuel pump from the design source, reduces the production and processing costs of the centrifugal fuel pump, and shortens the production cycle.

[0006] The technical solution of the present invention:

[0007] A centrifugal fuel pump, which includes a front cover 1, a housing 2, an impeller 3, a boss nut 4, a prime mover drive shaft 6, a rear cover 7, a screw 10, and a lock nut 11.

[0008] The rear cover 7 and the front cover 1 of the centrifugal fuel pump are connected to the middle housing 2 through screws 10.

[0009] Furthermore, the impeller 3 adjusts the clearance between the impeller 3 and the front cover 1 and the rear cover 7 through an adjustment gasket 5; the front cover 1 and the housing 2 are sealed through a sealing rubber ring B9, and the rear cover 7 and the housing 2 are sealed through a sealing rubber ring A8.

[0010] The drive shaft 6 of the prime mover is connected to the impeller 3, and the connection between the drive shaft 6 of the prime mover and the impeller 3 is a clearance fit of hole and shaft; four impeller grooves are machined at the end face of the impeller 3 near one end of the front cover 1 for connecting with the boss nut 4. The impeller grooves are evenly distributed in the circumferential direction of the end face of the impeller 3, and the direction is along the axial direction of the end of the impeller 3; a thread of a certain length is machined at the end face of the drive shaft 6 of the prime mover near one end of the front cover 1; after the impeller 3 is installed on the drive shaft 6 of the prime mover, the boss nut 4 is screwed onto the drive shaft 6 of the prime mover and fitted with the impeller grooves on the impeller 3. The impeller 3 and the drive shaft 6 of the prime mover are fixedly connected by tightening the boss nut 4. Then, the lock nut 11 is screwed onto the drive shaft 6 of the prime mover and tightened to prevent the boss nut 11 from loosening from the drive shaft 6 of the prime mover during the operation of the electric fuel pump, enhancing the connection reliability.

[0011] Further, four convex blocks are provided on the end face of the boss nut 4. The convex blocks are evenly distributed in the circumferential direction of the end face of the boss nut 4, and the direction is set along the axial direction of the end of the boss nut 4. The size of the convex blocks is the same as that of the impeller grooves on the impeller 3. The convex blocks are snapped into the impeller grooves on the impeller 3 to achieve fixation.

[0012] Advantages of the present invention for invention patent:

[0013] 1. The present invention for invention patent cancels the flat key connection mode between the impeller and the drive shaft, which can improve the machining processability and assembly processability of the impeller and the motor drive shaft, and enhance the maintainability of the product;

[0014] 2. The present invention for invention patent can improve the dynamic balance level of the impeller and the motor drive shaft during operation, reduce vibration and noise caused by uneven mass distribution, and improve the performance and service life of the electric fuel pump. Description of the drawings

[0015] Figure 1 It is a two-dimensional sectional view of the centrifugal fuel pump of the present invention.

[0016] Figure 2 It is a schematic diagram of the impeller of the present invention.

[0017] Figure 3 It is a schematic diagram of the boss nut of the present invention.

[0018] Figure 4 It is a schematic diagram of the assembly of the boss nut and the impeller of the present invention.

[0019] Figure 5 It is a schematic diagram of the assembly of the boss nut, the drive shaft of the prime mover and the impeller of the present invention.

[0020] In the figure: 1 front cover, 2 housing, 3 impeller, 4 boss nut, 5 adjusting gasket, 6 drive shaft of the prime mover, 7 rear cover, 8 sealing rubber ring A, 9 sealing rubber ring B, 10 screw, 11 self-locking nut. Detailed implementation manners

[0021] The following further describes the present invention patent in conjunction with the accompanying drawings and embodiments.

[0022] As Figure 1 shown, a centrifugal fuel pump includes a front cover 1, a housing 2, an impeller 3, a boss nut 4, an adjusting gasket 5, a prime mover drive shaft 6, a rear cover 7, a sealing rubber ring A 8, a sealing rubber ring B 9, a screw 10, and a locking nut 11.

[0023] A centrifugal fuel pump, the centrifugal fuel pump comprising a front cover 1, a housing 2, an impeller 3, a boss nut 4, an adjusting gasket 5, a prime mover drive shaft 6, a rear cover 7, a sealing rubber ring A 8, a sealing rubber ring B 9, a screw 10, and a locking nut 11.

[0024] The rear cover 7 and the front cover 1 of the centrifugal fuel pump are connected to the intermediate housing 2 by screws 10, and the clearance between the impeller 3 and the front cover 1 and the rear cover 7 is adjusted by the adjusting gasket 5; the front cover 1 and the housing 2 are sealed by the sealing rubber ring B 9, and the rear cover 7 and the housing 2 are sealed by the sealing rubber ring A 8.

[0025] The prime mover drive shaft 6 is connected to the impeller 3, and the connection between the prime mover drive shaft 6 and the impeller 3 is a clearance fit of hole and shaft; four impeller grooves are machined at the end face of the impeller 3 near the front cover 1 for connection with the boss nut 4, and the impeller grooves are evenly distributed circumferentially on the end face of the impeller 3 and are opened axially along the end of the impeller 3; a certain length of thread is machined at the end face of the prime mover drive shaft 6 near the front cover 1; after the impeller 3 is installed on the prime mover drive shaft 6, the boss nut 4 is screwed onto the prime mover drive shaft 6 and fitted with the impeller grooves on the impeller 3, and the impeller 3 and the prime mover drive shaft 6 are fixedly connected by tightening the boss nut 4; four convex blocks are provided on the end face of the boss nut 4, the convex blocks are evenly distributed circumferentially on the end face of the boss nut 4 and are set axially along the end of the boss nut 4, and the size of the convex blocks is the same as that of the impeller grooves on the impeller 3. The convex blocks are snapped into the impeller grooves on the impeller 3 to achieve fixation. Then the locking nut 11 is screwed onto the prime mover drive shaft 6 and tightened to prevent the boss nut 11 from loosening from the prime mover drive shaft 6 during the operation of the electric fuel pump and enhance the connection reliability.

[0026] During use, the prime mover drive shaft 6 rotates to drive the boss nut 4 to rotate. Since the boss of the boss nut 4 is engaged with the impeller groove, the impeller 3 is further driven to rotate.

[0027] The above is only the specific implementation manner of the present invention patent, but the protection scope of the present invention patent is not limited thereto. Any change or replacement that can be thought of without creative labor should be covered within the protection scope of the present invention patent. Therefore, the protection scope of the present invention patent should be subject to the protection scope defined by the claims.

Claims

1. A centrifugal fuel pump, characterized in that, The centrifugal fuel pump includes a front cover (1), a housing (2), an impeller (3), a boss nut (4), a prime mover drive shaft (6), a rear cover (7), screws (10), and a lock nut (11). The rear cover (7) and the front cover (1) of the centrifugal fuel pump are connected to the intermediate housing (2) by screws (10). The prime mover drive shaft (6) is connected to the impeller (3), and the connection between the prime mover drive shaft (6) and the impeller (3) is a clearance fit of hole and shaft; four impeller grooves are machined at the end face of the impeller (3) near the front cover (1) for connection with the boss nut (4). The impeller grooves are evenly distributed circumferentially on the end face of the impeller (3) and are opened axially along the end of the impeller (3); a thread of a certain length is machined at the end face of the prime mover drive shaft (6) near the front cover (1); after the impeller (3) is installed on the prime mover drive shaft (6), the boss nut (4) is screwed onto the prime mover drive shaft (6) and fitted with the impeller grooves on the impeller (3). The impeller (3) and the prime mover drive shaft (6) are fixedly connected by tightening the boss nut (4). Then, the lock nut (11) is screwed onto the prime mover drive shaft (6) and tightened to prevent the boss nut 11 from loosening from the prime mover drive shaft (6) when the electric fuel pump is working, enhancing the connection reliability.

2. The centrifugal fuel pump according to claim 1, characterized in that, The clearance between the impeller (3) and the front cover (1) and the rear cover (7) is adjusted by an adjusting gasket (5); the front cover (1) and the housing (2) are sealed by a sealing rubber ring B (9), and the rear cover (7) and the housing (2) are sealed by a sealing rubber ring A (8).

3. A centrifugal fuel pump according to claim 1, characterized in that, Four convex blocks are provided on the end face of the boss nut (4). The convex blocks are evenly distributed circumferentially on the end face of the boss nut (4) and are set axially along the end of the boss nut (4). The size of the convex blocks is the same as that of the impeller grooves on the impeller (3); the convex blocks are snapped into the impeller grooves on the impeller (3) to achieve fixation.

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