An internal gear electro-hydraulic pump

Abstract

This invention discloses an internal meshing gear electro-hydraulic pump, comprising: a pump housing, a motor, and temperature sensors; the pump housing has oil outlets at both ends and an oil inlet on its surface; the motor is disposed inside the pump housing, the motor stator is connected to the pump housing, and an internal meshing gear assembly is disposed inside the motor stator; at least one fan-shaped flow channel is arranged on the inner wall of the pump housing along the circumference of the motor stator, the inlet of the fan-shaped flow channel is connected to the oil inlet, and the outlet of the fan-shaped flow channel is connected to the low-pressure oil suction area of ​​the internal meshing gear assembly; multiple temperature sensors are evenly arranged along the circumference of the motor stator for real-time monitoring of the temperature of the motor stator. The electro-hydraulic pump of this invention, by opening the fan-shaped channels, can both cool the motor and heat the oil, increasing its fluidity.

Description

Technical Field

[0001] This invention relates to the field of electro-hydraulic pump technology, and more specifically to an internal gear electro-hydraulic pump. Background Technology

[0002] Internal gear pumps are widely used in hydraulic systems, lubrication systems, and cooling systems due to their compact structure, low flow pulsation, and low noise. With the increasing demands for miniaturization and integration in equipment, electro-hydraulic pump technology has emerged, integrating the motor with the internal gear pump into a single unit.

[0003] However, existing internal gear electro-hydraulic pumps still have the following technical problems in practical applications:

[0004] First, in highly integrated electro-hydraulic pumps, the motor stator core generates a significant amount of heat during operation, while the pump body has limited internal space and poor heat dissipation. Prolonged continuous operation or high-load conditions can lead to excessive motor temperature rise, causing a decline in the performance of the permanent magnets or even demagnetization, thus affecting the reliability and lifespan of the electro-hydraulic pump.

[0005] Secondly, there is a lack of real-time monitoring of the motor's thermal state. Most existing electro-hydraulic pumps are not equipped with temperature monitoring devices, making it impossible to obtain real-time temperature information of the motor stator core or other key internal components. This makes it difficult to achieve intelligent diagnosis and flexible control of the electro-hydraulic pump's operating status, and to adjust operating parameters or issue early warnings in a timely manner based on temperature changes.

[0006] Therefore, developing an internal gear electro-hydraulic pump that can cool the motor and extend its service life is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides an internal gear electro-hydraulic pump that can cool the motor and extend its service life.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: An internal gear electro-hydraulic pump, comprising: The pump housing has oil outlets at both ends and an oil inlet on its surface. An electric motor is disposed inside the pump housing. The motor stator is connected to the pump housing, and an internal meshing gear assembly is disposed inside the motor stator. At least one fan-shaped flow channel is disposed on the inner wall of the pump housing along the circumferential direction of the motor stator. The inlet of the fan-shaped flow channel is connected to the oil inlet, and the outlet of the fan-shaped flow channel is connected to the low-pressure oil suction zone of the internal meshing gear assembly. A portion of the oil entering through the oil inlet exchanges heat with the motor stator when flowing through the fan-shaped flow channel, and then enters the low-pressure oil suction zone of the internal meshing gear assembly. Another portion of the oil directly enters the low-pressure oil suction zone of the internal meshing gear assembly, and then enters the high-pressure oil discharge zone, and is discharged from the oil outlet. A plurality of temperature sensors are evenly arranged along the circumference of the motor stator for real-time monitoring of the motor stator temperature.

[0009] Preferably, the internal meshing gear assembly includes: a gear, a crescent block, and a fusion rotor; the fusion rotor is placed inside the motor stator and rotates relative to the motor stator; an internal gear ring is provided inside the fusion rotor, the gear is eccentrically arranged inside the fusion rotor and meshes with the internal gear ring; the crescent block is placed in the cavity between the gear and the internal gear ring, and divides the cavity into a low-pressure oil suction zone and a high-pressure oil discharge zone.

[0010] Preferably, a permanent magnet is provided on the outer circumferential surface of the fusion rotor.

[0011] Preferably, the surface of the permanent magnet is coated with epoxy resin.

[0012] Preferably, end caps are provided at both ends of the pump casing.

[0013] Preferably, a baffle is provided at one end of the end cap facing the pump housing, and the central shaft of the gear is rotatably connected to the baffle; the surface of the baffle is provided with an oil inlet groove and an oil outlet groove, the oil inlet groove is connected to the low-pressure oil suction area and the oil inlet or the low-pressure oil suction area and the end of the fan-shaped flow channel; the oil outlet groove is connected to the high-pressure oil discharge area and the oil outlet.

[0014] Preferably, bearings are provided at the connection points between the outer ends of the fusion rotor and the pump casing.

[0015] Preferably, a sealing ring is provided at the contact points between the pump body and the end cover.

[0016] Preferably, the device also includes a controller, which is connected to the temperature sensor signal and is used to adjust the motor speed according to the temperature signal fed back by the temperature sensor.

[0017] Preferably, a lifting ring is provided on the outside of the pump casing.

[0018] As can be seen from the above technical solution, compared with the prior art, the present invention discloses an internal meshing gear electro-hydraulic pump, the beneficial effects of which are: (1) By setting a fan-shaped flow channel between the inner wall of the pump casing and the motor stator, a portion of the oil entering through the inlet flows through the fan-shaped flow channel and exchanges heat with the motor stator, thereby achieving active cooling of the motor stator, effectively reducing the motor temperature rise, preventing the permanent magnet from demagnetizing due to high temperature, and improving the reliability and service life of the electro-hydraulic pump; at the same time, this portion of oil is preheated before entering the low-pressure oil suction zone, which improves the fluidity of the oil in the low-temperature environment and reduces the oil suction resistance. (2) Multiple temperature sensors are evenly arranged along the circumference of the motor stator, which can monitor the temperature distribution of the motor stator in real time. Combined with the controller, the motor speed can be adjusted according to the temperature signal to achieve flexible flow control and adapt to different working conditions. (3) The fusion rotor structure is adopted, and the permanent magnet is directly embedded on the outer circumference of the fusion rotor as the rotor of the motor. This eliminates the need for the traditional external shaft and coupling, resulting in a highly integrated structure and eliminating the risk of external leakage. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 A schematic diagram of the structure of the electro-hydraulic pump provided by the present invention; Figure 2 Right view of the electro-hydraulic pump provided by the present invention; Figure 3 This is a schematic diagram of the internal structure of the end cap provided by the present invention; Figure 4 This is an internal sectional view of the electro-hydraulic pump provided by the present invention. Figure 5 Top view of the electro-hydraulic pump provided by the present invention; Figure 6 Provided by the present invention Figure 5 Sectional view at point AA; Figure 7 Provided by the present invention Figure 5 Sectional view at point BB; Figure 8 Provided by the present invention Figure 5 Sectional view at CC; Figure 9 Provided by the present invention Figure 5 Sectional view at point DD; Figure 10 This is a schematic diagram of the structure of the motor stator provided by the present invention; Figure 11 A schematic diagram of the fusion rotor provided by the present invention; Figure 12 A side view of the fusion rotor provided by the present invention.

[0021] In the figure, 1-Pump housing; 11-Oil outlet; 12-Oil inlet; 13-Fan-shaped flow channel; 14-Low-pressure oil suction zone; 15-High-pressure oil discharge zone; 2-Motor stator; 3-Internal meshing gear assembly; 31-Gear; 32-Crescent block; 33-Merged rotor; 4-Temperature sensor; 5-Permanent magnet; 6-End cover; 61-Baffle; 62-Oil inlet groove; 63-Oil discharge groove; 7-Bearing; 8-Lifting ring; 9-Sealing ring. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figures 1 to 12 As shown in the figure, an embodiment of the present invention discloses an internal meshing gear electro-hydraulic pump, including: a pump housing 1, a motor and a temperature sensor 4.

[0024] The pump casing 1 has oil outlets 11 at both ends and an oil inlet 12 on its outer circumferential surface. A lifting ring 8 is also provided on the outside of the pump casing 1 for easy handling and installation. A flow divider is provided inside the pump casing 1, and the oil inlet 12 is connected to the flow divider. After the oil flows in from the oil inlet 12, it passes through the flow divider, causing a portion of the oil to enter the fan-shaped flow channel 13, while the other portion directly enters the low-pressure suction zone 14 at the left end of the pump casing 1. The fan-shaped flow channel serves to dissipate heat from the stator, provide low-temperature preheating, and supply oil to the pump.

[0025] The motor is located inside the pump casing 1. The motor includes a motor stator 2 and a fused rotor 33. The motor stator 2 is fixedly connected to the pump casing 1, and an internal meshing gear assembly 3 is provided inside the motor stator 2.

[0026] The internal meshing gear assembly 3 includes a gear 31, a crescent block 32, and a fusion rotor 33. The fusion rotor 33 is located inside the motor stator 2 and can rotate relative to the motor stator 2. An internal gear ring is provided inside the fusion rotor 33, and the gear 31 is eccentrically arranged inside the fusion rotor 33 and meshes with the internal gear ring. The crescent block 32 is placed in the cavity between the gear 31 and the internal gear ring, and divides the cavity into a low-pressure oil suction zone 14 and a high-pressure oil discharge zone 15. When the fusion rotor 33 rotates, it drives the gear 31, which meshes with its internal gear ring, to rotate, realizing the exchange of oil from the low-pressure oil suction zone to the high-pressure oil discharge zone.

[0027] The integrated rotor 33 can serve as the rotor of the motor. This integrated design not only improves space utilization but also eliminates the connecting component of the external shaft of the internal gear pump, thus completely eliminating external leakage.

[0028] Involute internal gear pairs are used to improve gear meshing efficiency and reduce energy loss. The displacement of the gear pump is increased by appropriately increasing the tooth width, while gear parameters, including the number of teeth, module, and tooth profile, are precisely calculated to ensure efficient gear operation.

[0029] Multiple permanent magnets 5 are embedded on the outer circumference of the fusion rotor 33. The surface of the permanent magnets 5 is coated with epoxy resin, and the magnetization method is parallel magnetization. When the motor stator 2 is energized, the permanent magnets 5 interact with the motor stator 2 to generate rotational force, which drives the fusion rotor 33 to rotate. The fusion rotor 33 drives the gear 31 to rotate, thereby realizing the suction and discharge of oil.

[0030] At least one fan-shaped flow channel 13 is provided on the inner wall of the pump casing 1 along the circumferential direction of the motor stator 2. In this embodiment, there are 6 fan-shaped flow channels 13 (e.g., ...). Figure 6-9 As shown), and evenly arranged along the outer circumference of the motor stator 2. The inlet of the fan-shaped flow channel 13 is connected to the oil inlet 12, and the outlet of the fan-shaped flow channel 13 is connected to the low-pressure oil suction area 14 at the right end of the internal meshing gear assembly 3.

[0031] During operation, the oil entering through inlet 12 is divided into two paths: one part of the oil enters the fan-shaped flow channel 13, where it exchanges heat with the motor stator 2, absorbing the heat generated by the stator 2 and cooling it down. Simultaneously, this portion of oil itself experiences a temperature increase and improved flowability (achieving low-temperature preheating), before entering the low-pressure suction zone 14 at the right end of the pump casing 1. The other part of the oil bypasses the fan-shaped flow channel 13 and directly enters the low-pressure suction zone 14 at the left end of the pump casing 1. In the low-pressure suction zone 14, both paths of oil are forced into the high-pressure discharge zone 15 through the meshing of gear 31 with the internal gear ring of the fused rotor 33, and finally discharged from the outlets 11 at both ends of the pump casing 1. During the suction and discharge process, the flowing oil continuously lubricates the bearings of the fused rotor and gears, extending their service life.

[0032] The design employs a fully enclosed structure where the motor and gear pump share a common housing, completely eliminating the traditional gear pump's external power shaft and its dynamic sealing components. This design transforms what is traditionally considered "external leakage" into "internal leakage" within the pump casing, which can be recovered through internal flow channels, fundamentally eliminating the risk of lubricating medium leakage.

[0033] Multiple temperature sensors 4 are evenly arranged along the circumference of the motor stator 2 (e.g.) Figure 10 As shown in the figure, it is used to monitor the temperature of the motor stator 2 in real time. The temperature sensor 4 can be a thermocouple or a thermistor, and its signal line is led out to an external controller.

[0034] End caps 6 are provided at both ends of the pump casing 1. A baffle 61 is provided at the end of the end cap 6 facing the pump casing 1 (e.g., Figure 3 (As shown). The central shaft of gear 31 is rotatably connected to baffle 61. The surface of baffle 61 is provided with an oil inlet groove 62 and an oil outlet groove 63. The oil inlet groove 62 of the left end cover connects to the inlet of the low-pressure oil suction zone 14 and the fan-shaped flow channel 13 at the left end; the oil outlet groove 63 at the left end connects to the high-pressure oil discharge zone 15 and the left oil outlet 11 at the left end cover. The oil inlet groove 62 of the right end cover connects to the outlet of the low-pressure oil suction zone 14 and the fan-shaped flow channel 13 at the right end; the oil outlet groove 63 at the right end connects to the high-pressure oil discharge zone 15 and the right oil outlet 11 at the right end cover. Baffle 61 serves both as a flow distributor and a support.

[0035] Bearings 7 are installed at the connection points between the external ends of the fusion rotor 33 and the pump housing 1. In this embodiment, the bearings 7 adopt a composite bearing design: a sliding bearing is used at the position supporting the central shaft of the gear 31, and a rolling bearing (such as a needle roller bearing) is used at the position supporting the fusion rotor 33. This combination improves load-bearing capacity and stability, and reduces wear.

[0036] Sealing rings 9 are provided at the contact points between the pump body 1 and the end cover 6, as well as at other mating surfaces where leakage may occur, to ensure that the whole machine has no external leakage.

[0037] It also includes a controller (not shown in the figure), which is connected to temperature sensor 4 and is used to adjust the motor speed based on the temperature signal fed back by temperature sensor 4. For example, when the temperature of motor stator 2 is detected to be too high, the controller can reduce the motor speed to reduce heat generation or issue an alarm signal; when it is necessary to increase the output flow, the controller can increase the motor speed. The controller can also communicate with a host computer to realize intelligent lubrication management.

[0038] To meet the low-pressure, high-flow requirements of the integrated thin oil lubrication system, the gear 31 in this embodiment can have its tooth width appropriately increased. Compared with conventional internal gear pumps, by increasing the tooth width of the gear, the basic displacement can be effectively increased without increasing the radial dimension.

[0039] As a further optimization, the outlet end of the fan-shaped flow channel 13 can be extended to the location of the bearing 7 (that is, some branch oil passages of the fan-shaped flow channel 13 first flow through the bearing 7 and then undergo heat exchange), so that the oil flowing through the fan-shaped flow channel 13 can cool the motor and also force lubricate the bearing 7, thereby further improving the bearing life.

[0040] The number and cross-sectional shape of the fan-shaped flow channels 13 can be adjusted according to the heat distribution of the motor stator 2. For example, wider fan-shaped flow channels can be provided in areas with higher heat generation.

[0041] Summary of working principles When the motor is started, the motor stator 2 generates a rotating magnetic field, driving the fused rotor 33, which is embedded with permanent magnets 5, to rotate. The internal gear ring of the fused rotor 33 drives the gear 31 to rotate. Oil enters the pump housing 1 from the oil inlet 12. Part of it enters the fan-shaped flow channel 13, flows along the surface of the motor stator 2, absorbs heat from the motor, and its temperature rises and viscosity decreases before entering the low-pressure oil suction zone 14. The other part directly enters the low-pressure oil suction zone 14. In the low-pressure oil suction zone 14, the oil fills the tooth grooves of the gear 31 and the internal tooth grooves of the fused rotor 33. As the gear 31 and the fused rotor 33 mesh and rotate, the inter-tooth volume decreases, the oil is compressed to form high pressure, enters the high-pressure oil discharge zone 15, and is finally discharged from the pump through the oil discharge groove 63 on the baffle 61 and the oil outlet 11. Throughout the process, the temperature sensor 4 monitors the temperature of the motor stator 2 in real time, and the controller adjusts the motor speed according to the temperature signal to achieve dual control of flow rate and temperature.

[0042] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0043] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An internal gear electro-hydraulic pump, characterized in that, include: The pump housing has oil outlets at both ends and an oil inlet on its surface. An electric motor is disposed inside the pump housing. The motor stator is connected to the pump housing, and an internal meshing gear assembly is disposed inside the motor stator. At least one fan-shaped flow channel is disposed on the inner wall of the pump housing along the circumferential direction of the motor stator. The inlet of the fan-shaped flow channel is connected to the oil inlet, and the outlet of the fan-shaped flow channel is connected to the low-pressure oil suction zone of the internal meshing gear assembly. A portion of the oil entering through the oil inlet exchanges heat with the motor stator when flowing through the fan-shaped flow channel, and then enters the low-pressure oil suction zone of the internal meshing gear assembly. Another portion of the oil directly enters the low-pressure oil suction zone of the internal meshing gear assembly, and then enters the high-pressure oil discharge zone, and is discharged from the oil outlet. A plurality of temperature sensors are evenly arranged along the circumference of the motor stator for real-time monitoring of the motor stator temperature.

2. The internal gear electro-hydraulic pump according to claim 1, characterized in that, The internal meshing gear assembly includes: a gear, a crescent block, and a fusion rotor; the fusion rotor is placed inside the motor stator and rotates relative to the motor stator; an internal gear ring is provided inside the fusion rotor, the gear is eccentrically arranged inside the fusion rotor and meshes with the internal gear ring; the crescent block is placed in the cavity between the gear and the internal gear ring, and divides the cavity into a low-pressure oil suction zone and a high-pressure oil discharge zone.

3. The internal gear electro-hydraulic pump according to claim 2, characterized in that, A permanent magnet is provided on the outer circumference of the fusion rotor.

4. The internal gear electro-hydraulic pump according to claim 3, characterized in that, The surface of the permanent magnet is coated with epoxy resin.

5. The internal gear electro-hydraulic pump according to claim 1, characterized in that, The pump casing is provided with end caps at both ends.

6. The internal gear electro-hydraulic pump according to claim 5, characterized in that, A baffle is provided at one end of the end cap facing the pump housing, and the central shaft of the gear is rotatably connected to the baffle; an oil inlet groove and an oil outlet groove are provided on the surface of the baffle, the oil inlet groove is connected to the low-pressure oil suction area and the oil inlet or the low-pressure oil suction area and the end of the fan-shaped flow channel; the oil outlet groove is connected to the high-pressure oil discharge area and the oil outlet.

7. An internal gear electro-hydraulic pump according to claim 2, characterized in that, Bearings are provided at the connection points between the outer ends of the fusion rotor and the pump casing.

8. An internal gear electro-hydraulic pump according to claim 5, characterized in that, The contact points between the pump body and the end cover are all equipped with sealing rings.

9. An internal gear electro-hydraulic pump according to claim 1, characterized in that, It also includes a controller, which is connected to the temperature sensor signal and is used to adjust the motor speed according to the temperature signal fed back by the temperature sensor.

10. An internal gear electro-hydraulic pump according to claim 1, characterized in that, The pump casing is equipped with lifting rings on its exterior.

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