Nested motor pump with self-pressurization function

Abstract

The nested motor pump with the self-pressurization function comprises a shell, a motor and a gear pump, an inner rotor and an outer rotor of the motor are designed to be of an integrated detachable structure, the gear pump is embedded in the shell, the inner rotor drives the outer rotor and a driving wheel of the gear pump to rotate at the same time, the outer rotor rotates in the rotating process, and the gear pump rotates in the rotating process. The spiral blades on the outer rotor can convey and pressurize the oil liquid, and the oil liquid is stably conveyed to the gear pump. The motor pump solves the problems of negative pressure and insufficient oil supply during high-speed operation of a motor pump in the prior art under the condition that the motor pump is not externally connected with an independent supercharging device, and the overall structure of the motor pump is more compact.

Description

Technical Field

[0001] The invention belongs to the technical field of fluid machinery, and in particular relates to a nested motor pump with a self-pressurizing function. Background Art

[0002] Traditional hydraulic power units usually adopt a "three-stage" structure, that is, they are composed of an independent electric motor (or internal combustion engine), a coupling and an independent hydraulic pump. This structure is large in size and weight, which increases the complexity and cost of the system. The cooling fan in the independent electric motor also increases the noise of the entire power unit, and there are external leakage paths. In addition, when the traditional gear pump is running at high speed, it is easy to have insufficient oil absorption, resulting in negative pressure in the pump body, affecting the stability and service life of the pump. In recent years, people's requirements for hydraulic equipment have been continuously improved, and integrated, silent, and high-speed motor pumps have become an important direction for the innovation and development of hydraulic technology.

[0003] Through searching the existing patent documents, it is found that some of the prior art discloses motor pumps that can solve the problems of insufficient oil suction, high noise, and low efficiency at high speeds, but at high speeds, an external booster pump is required, which increases the complexity of the system. Other prior art discloses that the gear pump structure is more compact and reasonable by placing the outer rotor motor into the inner cavity of the driving gear, and the gear pump motor and the pump body are integrated. However, its radial size is large, and it is easy to have insufficient oil suction at high speeds.

[0004] In summary, there is a need for a motor pump that has a compact structure, can stably supply oil at high speeds, has reliable performance, and has a wide range of applications. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a nested motor pump with a self-pressurizing function, which combines a motor with a gear pump to form a motor pump device with high integration and low noise.

[0006] The present invention is achieved through the following technical solutions: A nested motor pump with a self-pressurizing function comprises a housing, a motor and a gear pump, wherein the housing comprises a first cylindrical shell and a first shell cover, wherein one end of the first shell is open and sealed by the first shell cover, and the motor is built into an inner cavity of the first shell; The motor comprises an outer rotor, an inner rotor and a stator which are coaxially arranged, the area between the outer rotor and the housing forms an oil chamber, the stator is sleeved in the inner chamber of the outer rotor, the inner rotor is sleeved in the inner chamber of the stator and forms an electromagnetic coupling relationship with the stator, and the outer rotor rotates as the inner rotor rotates; A pump body mounting hole connected with the first housing is provided on the side wall at the other end of the first housing, and the gear pump is embedded in the pump body mounting hole. The gear pump comprises a pump body, a driven wheel and a driving wheel, and the driving wheel is coaxial with the inner rotor. The driving wheel rotates with the rotation of the inner rotor, thereby driving the driven wheel to engage in transmission. The liquid enters the motor pump through the housing oil inlet provided on the cylinder of the first housing, and under the action of the outer rotor, flows into the gear pump inlet from the first oil outlet connected with the pump body mounting hole, and under the action of the gear meshing rotation, the oil flows out from the second oil outlet connected with the pump body mounting hole, thereby realizing the transportation of the oil.

[0007] Furthermore, the first shell and the first shell cover are connected by bolts, the outer rotor and the inner rotor are fixed to the first shell cover via a first bearing and a second bearing respectively, and the stator is fixed to the first shell cover via a stator bracket.

[0008] Furthermore, a first bearing mounting hole is correspondingly opened on the first shell cover, and the first bearing is axially fixed by a sealing device; a second bearing mounting hole is correspondingly opened on the first shell cover, and the second bearing is axially fixed by a retaining spring; a stator support hole is also correspondingly opened on the first shell cover for supporting the stator support frame.

[0009] Furthermore, the first shell cover is connected to the first shell body through bolts at the bolt hole A1; and is connected to the sealing device at the bolt hole B1.

[0010] Furthermore, the outer rotor includes a second shell and a second shell cover, the second shell cover is located at one end close to the gear pump and is connected to the second shell by bolts, and the second shell cover includes two symmetrical semicircular shell covers fixed on the inner rotor shaft.

[0011] Furthermore, spiral blades are processed on the outer surface of the second shell to transport oil through rotation.

[0012] Furthermore, one end of the gear pump is connected to the inner side of a section of the first housing through a left end cover, and the other end of the gear pump is connected to the outer side of the first housing through a right end cover, thereby sealing the pump body mounting hole.

[0013] Furthermore, the outer rotor is connected by a second shell and a second shell cover by bolts at bolt holes A2, the second shell is provided with a sealing ring groove for circumferential sealing of the second shell and the second shell cover, the second shell cover is connected by bolts at the bolt holes by two identical parts, and the second shell cover is also provided with a sealing groove for radial sealing between the second shell and the second shell cover.

[0014] Furthermore, the second shell cover is provided with an axial hole, which is used for positioning and fixing the outer rotor and the inner rotor through the positioning hole and the bolt hole, so that the outer rotor rotates with the inner rotor.

[0015] Furthermore, the pump body is provided with an oil inlet and an oil outlet, and the oil inlet and the oil outlet are respectively connected with the first oil outlet and the second oil outlet.

[0016] The beneficial effects of the present invention are: 1. The present invention applies a dual-rotor structural design to the motor pump structure, making the motor pump structure more compact, simplifying the structure and improving the integration.

[0017] 2. The spiral blades on the outer rotor are used to transport oil, which increases the flow rate and avoids the generation of negative pressure. At the same time, there is no external booster device, which improves the compactness, stability and service life of the pump body.

[0018] 3. When the motor pump does not need to work at a high speed, the outer rotor can be removed and a common housing can be installed, which reduces friction loss and improves the overall efficiency of the motor pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the principle diagram of the nested motor pump of the present invention; Figure 2 It is the overall assembly diagram of the present invention; Figure 3 It is a structural diagram of the motor pump housing of the present invention; Figure 4 is a schematic diagram of a first shell of the present invention; Figure 5 The structure diagram of the outer rotor and the partial view of the outer rotor of the present invention; Figure 6 It is a structural diagram of the gear pump of the present invention; Figure numerals: 1, right end cover, 2, gear pump, 21, pump body, 22, driven wheel, 23, driving wheel, 24, sliding bearing, 25, sliding bearing sealing ring, 26, pump body sealing ring, 2a, oil inlet, 2b, suction chamber, 2c, discharge chamber, 2d, oil outlet, 2g, inlet sealing groove, 2f, outlet sealing groove, 3, left end cover, 4, housing, 41, first housing, 42, first housing cover, 4a, bolt hole A1, 4b, bolt hole B1, 4c, first bearing mounting hole, 4d, stator support hole, 4f, Second bearing mounting hole, 4h, housing oil inlet, 4k, first oil outlet, 4j, pump body mounting hole, 4i, second oil outlet, 5, outer rotor, 51, second housing, 52, spiral blade, 53, second housing cover, 5a, bolt hole A2, 5b, sealing ring groove, 5c, positioning hole, 5d, shaft hole, 5g, bolt hole, 5f, sealing groove, 6, inner rotor, 7, stator, 8, stator support frame, 9, sealing device, 10, first bearing, 11, second bearing, 12, retaining ring, 13, oil chamber, 14, sealing ring. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0021] like Figures 1 to 6 As shown, the nested motor pump with self-pressurization function of the present invention comprises a right end cover 1, a gear pump 2, a left end cover 3, a housing 4, an outer rotor 5, an inner rotor 6, a stator 7, a stator support frame 8, a sealing device 9, a first bearing 10, a second bearing 11, and an oil chamber 13; The housing 4 includes a first housing 41 and a first housing cover 42, and the first housing 41 and the second housing cover 42 are connected by bolts; the right end cover 1 and the first housing cover 42 are both connected and sealed with the first housing 4 by bolts, and a pump body sealing ring 26 is also provided at the connection between the right end cover 1 and the first housing 4; the gear pump 2 is embedded in the pump body mounting hole on the right side of the first housing 41, and the left end cover 3 is connected with the gear pump 2 and the first housing 41 by bolts to seal the gear pump 2; the inner rotor 6 is sleeved in the inner cavity of the stator 7, and the inner rotor 6 is connected to the second shaft The bearing 11 is fixed on the left side to the first shell cover 41; the stator 6 is fixed on the first shell cover 42 through the stator support frame 8; the outer rotor 5 is fixed on the first shell cover 42 on the left side through the first bearing 10, and is fixed on the inner rotor 6 shaft on the right side through bolts and locating pins. The area between the outer rotor 5 and the shell 4 forms an oil chamber 13, which is connected to the shell oil inlet 4h. The oil flows in the oil chamber 13, and the outer rotor 5 rotates with the rotation of the inner rotor 6. The spiral blades 52 on the outer rotor 5 supply fluid to the gear pump 2 during the rotation process. When the motor pump does not need to work at a higher speed, the outer rotor 5 can be disassembled and a common shell can be installed, which reduces friction loss and improves the overall efficiency of the motor pump.

[0022] In order to improve the overall efficiency of the motor pump, an appropriate gap should be maintained between the inner and outer rotors of the motor and between the stator 7 and the inner rotor 6 to reduce friction loss. At the same time, the gear clearance of the gear pump should also be accurately adjusted to ensure the sealing performance of the pump body and the flow stability.

[0023] like Figure 2 and Figure 3As shown, the first shell cover 42 is connected to the first shell 41 by bolts at the bolt hole A1 4a; it is connected to the sealing device 9 at the bolt hole B1 4b, and a first bearing mounting hole 4c is provided on the first shell cover 42, and the first bearing 10 is axially fixed by the sealing device 9; a second bearing mounting hole 4f is provided on the first shell cover 42, and the second bearing 11 is axially fixed by the retaining ring 12; a stator support hole 4d is provided on the first shell cover 42 for supporting the stator support frame 8; the first shell 41 is provided with a shell oil inlet 4h, a first oil outlet 4k, a pump body mounting hole 4j, and a second oil outlet 4i; a heat sink is processed on the first shell 41 to ensure that the motor works within the normal temperature range.

[0024] like Figure 5 and Figure 6 As shown, the outer rotor 5 is connected by bolts at bolt hole A2 5a by the second housing 51 and the second housing cover 53. The second housing 51 is provided with a sealing groove 5b for sealing the second housing 51 and the second housing cover 53 in the circumferential direction. The second housing cover 53 is connected by bolts at bolt hole 5g by two identical parts. The second housing cover 53 is provided with a sealing groove 5f for sealing the second housing 51 and the second housing cover 53 in the radial direction. The second housing cover 53 is provided with an axial hole 5d, which is used for positioning and fixing the outer rotor 5 and the inner rotor 6 through the positioning hole 5c and the bolt hole 5g, so that the outer rotor 5 can rotate with the inner rotor 6. The second housing is processed with a spiral blade 52. The second housing 51 and the spiral blade 52 are of an integrated structure design. When the inner rotor 6 drives the outer rotor 5 to rotate, the spiral blade 52 pressurizes the oil chamber 13, increases the flow rate and avoids negative pressure, thereby providing stable oil supply to the gear pump 2. The arrangement of the spiral blades can also optimize the flow path of the oil and improve the delivery efficiency. In order to avoid negative pressure in the pump body, the spiral blades should be designed to ensure that the fluid can be continuously transported from the inlet to the outlet of the pump body during the operation of the motor to keep the pressure in the pump body stable.

[0025] like Figure 3 , Figure 4 and Figure 6As shown, the gear pump 2 is embedded in the pump body mounting hole 4j, and the gear pump 2 includes a pump body 21, a driving wheel 23, a driven wheel 22, and a sliding bearing 24. The sliding bearing 24 is also connected to a sliding bearing sealing ring 25. The tooth profiles of the driving wheel 23 and the driven wheel 22 are designed to be specific arc tooth profiles to reduce vibration and noise during meshing. The driving wheel rotates with the rotation of the inner rotor, thereby driving the driven wheel to mesh and transmit. An oil inlet 2a and an oil outlet 2d are provided on the pump body 21. The oil inlet 2a is communicated with the first oil outlet 4k, and the oil outlet 2d is communicated with the second oil outlet 4 i is connected, the oil flows in from the shell oil inlet port 4a on the oil inlet side of the shell, is pressurized and transported by the spiral blades 52 on the outer rotor 5, flows to the oil outlet side of the shell, and then flows out from the first oil outlet port 4k, enters the oil inlet port 2a, and flows to the suction chamber 2b. The oil enters the oil discharge chamber 2c along with the meshing transmission of the driving wheel 23 and the driven wheel 22 of the gear pump 2, flows out from the oil outlet port 2d, passes through the second oil outlet port 4i, and finally flows out of the motor pump, thereby realizing the input and output of the oil. An oil inlet sealing groove 2g and an oil outlet sealing groove 2f are provided on the pump body 21 for sealing between the pump body 21 and the first shell 41.

[0026] The working process is as follows: Open the oil tank. When the motor is powered on, the inner rotor 6 starts to rotate. Since the inner rotor 6 and the driving wheel 23 of the gear pump 2 share a common shaft, the driving wheel 23 also rotates. In the gear pump 2 part, the driven wheel 22 meshing with the driving wheel 23 also starts to rotate. At this time, the sealed working chamber in the pump body 21 is divided into two parts: the suction chamber 2b and the discharge chamber 2c, in preparation for the suction of oil. When the driving wheel 23 and the driven wheel 22 exit the meshing state, a partial vacuum is formed, and the oil flows into the oil chamber 13 from the shell oil inlet 4h on the shell 4, and the outside Under the action of atmospheric pressure, the oil continuously flows to the oil discharge side of the oil chamber 13. Since the first oil outlet 4k on the first housing 41 is connected to the oil inlet 2a on the pump body 21, the oil flows out from the first oil outlet 4k, passes through the oil inlet 2a, and enters the suction chamber 2b of the pump body 21. Under the action of the driving wheel 23 and the driven wheel 22, the oil enters the discharge chamber 2c. Since the oil outlet 2d on the pump body 21 is connected to the first oil outlet 4i on the first housing 41, the oil finally flows out from the oil outlet 2d, and is discharged to the outside of the motor pump through the second oil outlet 4i. In the process of the oil flowing from the oil inlet side of the oil chamber 13 to the oil discharge side, the outer rotor 5 rotates simultaneously with the rotation of the inner rotor 6, and the spiral blades 52 thereon also rotate accordingly, thereby pressurizing and delivering the oil, avoiding the occurrence of negative pressure and insufficient oil supply, and smoothly delivering the oil to the oil discharge side, ensuring the long-term stable operation of the motor pump.

[0027] It should be noted that although the present invention is described by the above embodiments, the present invention may also have other various embodiments. Without departing from the spirit and scope of the present invention, it is obvious that those skilled in the art may make various corresponding changes and deformations to the present invention, but these changes and deformations should all fall within the scope of protection of the appended claims of the present invention and their equivalents.

Claims

1. A nested motor pump with self-pressurization function, characterized in that: It comprises a housing (4), a motor and a gear pump (2); the housing (4) comprises a first cylindrical shell (41) and a first shell cover (42); one end of the first shell (41) is open and is sealed by the first shell cover (42); the motor is built into the inner cavity of the first shell (41); The motor comprises an outer rotor (5), an inner rotor (6) and a stator (7) which are coaxially arranged, the area between the outer rotor (5) and the outer casing (4) forming an oil chamber (13), the stator (7) being sleeved in the inner chamber of the outer rotor (5), the inner rotor (6) being sleeved in the inner chamber of the stator (7) and forming an electromagnetic coupling relationship with the stator (7), and the outer rotor (5) rotating as the inner rotor (6) rotates; A pump body mounting hole (4j) connected to the first housing (41) is provided on the side wall at the other end of the first housing (41). The gear pump (2) is embedded in the pump body mounting hole (4j). The gear pump (2) comprises a pump body (21), a driven wheel (22), and a driving wheel (23). The driving wheel (23) is coaxial with the inner rotor (6). The driving wheel (23) rotates as the inner rotor (6) rotates, thereby driving the driven wheel (22) to mesh and transmit. Liquid enters the motor pump through a housing oil inlet (4h) provided on the cylinder of the first housing (41). Under the action of the outer rotor (5), the liquid flows into the gear pump inlet from a first oil outlet (4k) connected to the pump body mounting hole (4j). Under the action of the meshing rotation of the gears, the oil flows out from a second oil outlet (4i) connected to the pump body mounting hole (4j), thereby realizing the transportation of the oil.

2. A nested motor pump with self-pressurization function according to claim 1, characterized in that: The first housing (41) and the first housing cover (42) are connected by bolts, the outer rotor (5) and the inner rotor (6) are fixed to the first housing cover (42) via a first bearing (10) and a second bearing (11) respectively, and the stator (6) is fixed to the first housing cover (42) via a stator support frame (8).

3. A nested motor pump with self-pressurization function according to claim 2, characterized in that: A first bearing mounting hole (4c) is correspondingly formed on the first shell cover (42), and the first bearing (10) is axially fixed by a sealing device (9); a second bearing mounting hole (4f) is correspondingly formed on the first shell cover (42), and the second bearing (11) is axially fixed by a retaining spring (12); and a stator support hole (4d) is also correspondingly formed on the first shell cover (42), and is used to support the stator support frame (8).

4. The nested motor pump with self-pressurization function according to claim 2, characterized in that: The first shell cover (42) is connected to the first shell body (41) via bolts at the bolt hole A1 (4a); and is connected to the sealing device (9) at the bolt hole B1 (4b).

5. The nested motor pump with self-pressurization function according to claim 1, characterized in that: The outer rotor (5) comprises a second housing (51) and a second housing cover (53); the second housing cover (53) is located at one end close to the gear pump (2) and is connected to the second housing (51) by bolts; the second housing cover (53) comprises two symmetrical semicircular housing covers fixed on the shaft of the inner rotor (6).

6. The nested motor pump with self-pressurization function according to claim 5, characterized in that: The outer surface of the second shell (51) is machined with spiral blades (52) for conveying oil by rotating.

7. The nested motor pump with self-pressurization function according to claim 1, characterized in that: One end of the gear pump (2) is connected to the inner side of a section of the first housing (41) via a left end cover (3), and the other end of the gear pump (2) is connected to the outer side of the first housing (41) via a right end cover (1), thereby sealing the pump body mounting hole (4j).

8. The nested motor pump with self-pressurization function according to claim 5, characterized in that: The outer rotor (5) is connected by bolts at a bolt hole A2 (5a) with a second housing (51) and a second housing cover (53); the second housing (51) is provided with a sealing ring groove (5b) for sealing the second housing and the second housing cover in a circumferential direction; the second housing cover (53) is connected by bolts at a bolt hole (5g) with two identical parts; the second housing cover (53) is also provided with a sealing groove (5f) for sealing the second housing (51) and the second housing cover (53) in a radial direction.

9. The nested motor pump with self-pressurization function according to claim 5, characterized in that: The second shell cover (53) is provided with an axial hole (5d) which is used for positioning and fixing the outer rotor (5) and the inner rotor (6) through the positioning hole (5c) and the bolt hole (5g), so that the outer rotor (5) rotates with the inner rotor (6).

10. The nested motor pump with self-pressurization function according to claim 1, characterized in that: The pump body (21) is provided with an oil inlet (2a) and an oil outlet (2d), and the oil inlet (2a) and the oil outlet (2d) are respectively connected to the first oil outlet (4k) and the second oil outlet (4i).

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