Gear pump

Patent metadata

Field	Value
Publication number	US-10415566-B2
Application number	US-201514885748-A
Country	US
Kind code	B2
Filing date	Oct 16, 2015
Priority date	Oct 16, 2014
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

A gear pump has a pump body, a pump cylinder connected with the pump body, a driving gear and a driven gear meshed with each other and disposed in the pump cylinder, and a motor driving the driving gear through a driving shaft. The pump cylinder is located between the pump body and the motor. The driving gear is mounted to or integrally formed with the driving shaft. A first bearing and a second bearing are disposed on respectively sides of the driving gear, one end of driving shaft is received in the first bearing, and the other end of the driving shaft extends through the second bearing and into the motor and forms a shaft of the motor.

First claim

The invention claimed is:

1. A gear pump comprising:
a pump cylinder, comprising:
a driving gear; and
a driven gear, the driving gear and the driving gear being meshed with each other and disposed in the pump cylinder;

a driving shaft, rotatably supported by the pump cylinder, and the driving gear being mounted to or integrally formed with the driving shaft; and
a motor, comprising:
a rotor attach to the driving shaft;
a stator surrounding the rotor; and
a sealing member disposed between the rotor and the stator, a gap being formed between the sealing member and the rotor to allow the rotor to rotate,

wherein the sealing member is a cylindrical structure with an open end and an opposite closed end, an end of the pump cylinder is inserted into the open end of the sealing member to contact an inner surface of the sealing member, and the open end of the sealing member is connected with the pump cylinder to prevent a leakage of a fluid in the gear pump,
wherein the driving shaft and the rotor are rotatable along with each other,
wherein the driving shaft and the rotor are engaged to permit a relative movement in an axial direction without permitting a relative movement in a circumferential direction after the driving shaft is assembled to the rotor,
wherein the end of the pump cylinder has an annular flange axially protrudes therefrom, and the annular flange is inserted into the open end of the sealing member to contact the inner surface of the sealing member,
wherein the end of the pump cylinder facing the motor further comprises at least one baffle block which extends radially inwardly from the annular flange and axially to form a gap between the baffle block and the rotor, and the fluid rotating along with the rotor impinges on the at least one baffle block to form turbulence in the fluid, and
wherein two baffle blocks are symmetrically disposed with respect to the driving shaft, and a radial distance between the at least one baffle block and the driving shaft gradually increases in a direction away from the pump cylinder.

2. The gear pump of claim 1 , wherein the sealing member is made of a non-magnetic metal material.

3. The gear pump of claim 1 , wherein the motor further comprises an outer housing, an end of the outer housing adjacent to the pump cylinder has a through hole, and the open end of the sealing member extends out of the outer housing via the through hole to connect the pump cylinder.

4. The gear pump of claim 1 , wherein the end of the pump cylinder further has an end surface located outside the annular flange, the sealing member further comprises a radial flange which extends radially outwardly from the open end of the sealing member, the radial flange is attached to the end surface of the pump cylinder, and a sealing ring is disposed between the end surface of the pump cylinder and the radial flange of the sealing member.

5. The gear pump of claim 1 , wherein an outer diameter of the annular flange is substantially the same as an inner diameter of the open end of the sealing member.

6. The gear pump of claim 1 , wherein a radial inner end of the at least one baffle block is spaced a distance from the driving shaft rotor to form a fluid channel therebetween to allow passage of the fluid.

7. The gear pump of claim 1 , wherein the annular flange of the pump cylinder is an outer annular flange, the pump cylinder further has an inner annular flange located inside the outer annular flange, the inner annular flange has a driving shaft hole configured to allow passage of the driving shaft, a radial inner end of the at least one baffle block is spaced a distance from the inner annular flange to form a fluid channel therebetween to allow passage of the fluid.

8. The gear pump of claim 1 , further comprising a pump body connected with the pump cylinder,
wherein the driving shaft extends into the pump body and further rotatably supported by the pump body.

9. The gear pump of claim 8 , wherein the pump body has a fluid inlet and a fluid outlet via which the fluid flows into and out of the pump body, respectively.

10. The gear pump of claim 8 , wherein a first washer is disposed between the pump body and one end surface of the driving gear, a second washer is disposed between the pump cylinder and the other end surface of the driving gear, and the first washer and the second washer are made from stainless steel.

11. The gear pump of claim 1 , wherein the rotor comprises a housing, a rotor core received in the housing, a magnet disposed between the rotor core and the housing, and an insulating member, the insulating member is directly formed over the housing, rotor core and magnet to form an integral structure by a molding process, the magnet and rotor core are sealed in a closed space formed by the housing and the insulating member, and the insulating member forms a through hole for receiving the driving shaft.

12. The gear pump of claim 11 , wherein the housing is made of a non-magnetic metal material.

13. The gear pump of claim 1 , wherein the rotor defines therein a through hole, a portion of the through hole has a non-circular cross section, a portion of the driving shaft received in the through hole has a corresponding cross section, such that relative rotation between the rotor and the driving shaft is limited.

14. The gear pump of claim 1 , wherein the rotor defines therein a through hole and a keyway in communication with the through hole, a key is disposed in the keyway, the driving shaft forms a cutting groove at a location corresponding to the key, matching surfaces of the key and the driving shaft are planar surfaces, such that relative rotation between the rotor and the driving shaft is limited.

15. The gear pump of claim 14 , wherein an axial height of the cutting groove is greater than an axial height the key, a locking groove is formed in the driving shaft corresponding to the cutting groove, the locking groove is located on a side of the rotor remote from the pump cylinder, and a retaining ring is disposed in the locking groove to limit axial movement of the rotor.

16. The gear pump of claim 1 , wherein a clearance is formed between the driving shaft and a driving shaft hole of the pump cylinder, and a fluid in the pump cylinder is driven to enter the sealing member via the clearance.

Assignees

• Johnson Electric Int Ag

Inventors

• Ramadoss Mohanlal
• Liu Wu
• Ngai Chi Hang

Classifications

• F04C15/008 Primary

  Prime movers · CPC title

• F04C2/18

  with similar tooth forms (F04C2/16 takes precedence) · CPC title

• F04C2240/10

  Stators · CPC title

• F04C2240/30

  Casings or housings · CPC title

• F04C2240/40

  Electric motor · CPC title