Bidirectional cycloid oil pump

Abstract

The utility model discloses a bidirectional cycloid oil pump, and belongs to the technical field of oil pumps. The inner rotor and the outer rotor are installed in the pump body assembly, the oil pump shaft is connected with an external power shaft, the inner rotor is fixedly installed on the oil pump shaft, the inner rotor is sleeved with the outer rotor, outer teeth of the inner rotor are meshed with inner teeth of the outer rotor, and inner teeth of the outer rotor and outer teeth of the inner rotor form a cycloid meshing structure; a reversing disc is arranged on the outer rotor in a sliding mode, a positioning pin is arranged on one end face of the reversing disc, a limiting groove is formed in the inner side of the pump body, the positioning pin slides in the limiting groove, and the sliding stroke of the positioning pin is limited to be 180 degrees. On the premise of not depending on an external independent oil pump unit, the oil pump can adapt to positive and negative rotation of the motor, it is ensured that lubricating oil can be stably provided for the gearbox in different steering directions, meanwhile, the function stability of the oil suction cavity and the oil outlet cavity is maintained, the structure of a marine power system is simplified, and cost and operation complexity are reduced.

Description

Technical Field

[0001] This utility model mainly relates to the field of oil pump technology, specifically a bidirectional cycloidal oil pump. Background Technology

[0002] Currently, common types of oil pumps that supply working oil include external gear pumps, internal gear pumps, cycloidal rotor pumps (referred to as rotor pumps), vane pumps, and plunger pumps. These oil pumps all use a method of suction at one end and discharge at the other end, that is, they are equipped with one suction pipe and one discharge pipe.

[0003] With the development of clean energy, electric propulsion has been applied in fields such as water transportation. Electric motors, as prime movers, together with gearboxes and propellers, form marine propulsion units for water navigation. Because electric motors can rotate instantly in either direction, conventional gearboxes do not require clutches or reversing devices, thus simplifying their structure. However, gearboxes still require lubricating oil during operation to lubricate the gears and bearings, and this lubricating oil needs to be cooled by a cooler, which relies on an oil pump to circulate the lubricating oil.

[0004] In existing technology, the oil pump, gearbox, and motor shaft are typically connected on the same axis and rotate together. When the motor rotates forward, the oil pump operates in a predetermined direction of rotation, and its suction and discharge pipes are fixed in position. However, when the motor rotates in reverse, because the oil pipes are fixedly installed, they cannot rotate in reverse, causing the oil pump to fail to properly draw in and discharge oil.

[0005] The current practical solution involves designing a dedicated oil pump unit outside the gearbox. This unit includes a motor with an external power supply and an oil pump connected to it. The oil pump draws oil from the gearbox oil sump and then delivers the oil back to the gearbox to achieve lubrication or cooling. When the motor, gearbox, and propeller are operating, the oil pump motor needs to be started first to ensure the oil pump is operational and meets the lubrication requirements of the main propulsion motor, gearbox, and propeller.

[0006] However, this existing technical solution has many drawbacks, such as high operating costs, requiring an additional oil pump motor unit, which increases equipment and maintenance costs; inconvenient operation, requiring separate operation of the oil pump motor to start and stop, which increases the operation steps and complexity; and a complex overall system structure that occupies a large amount of space on board, which is not conducive to the lightweighting and space optimization of ships.

[0007] In summary, existing technologies have many shortcomings in meeting the requirements for lubricating oil supply and cooling in marine gearboxes, and there is an urgent need for an oil pump solution that can adapt to bidirectional motor rotation, has a simple structure, low cost, and is easy to operate. Utility Model Content

[0008] This invention solves the problem of reversed oil suction and discharge directions caused by bidirectional rotation of the input shaft in ordinary oil pumps by using a dynamic limiting coupling mechanism between the commutator and the outer rotor. The oil pump structure of this invention simplifies marine power units, giving the gearbox a complete integrated structure, ensuring the transmission of motor functions and the integrity of gearbox functions, without relying on an external oil pump for gearbox lubrication and cooling.

[0009] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0010] This utility model provides a bidirectional cycloidal oil pump, including a pump body assembly, an oil pump shaft, an inner rotor, an outer rotor, and a reversing disc. The pump body assembly is bolted together with a front cover, a pump body, and a rear cover to form a sealed chamber. The oil pump shaft passes through the pump body and is supported by a front bearing and a rear bearing; the inner rotor is fixed in the middle of the shaft, and it meshes eccentrically with the outer rotor to form a suction chamber and an outlet chamber with varying volumes.

[0011] An inner rotor is fixedly mounted on the pump shaft, and an outer rotor is fitted onto the inner rotor. The outer teeth of the inner rotor mesh with the inner teeth of the outer rotor, and the inner teeth of the outer rotor and the outer teeth of the inner rotor form a cycloidal meshing structure. A reversing disc is slidably mounted on the outer rotor, and the two form a friction transmission pair through a clearance fit. The outer wall of the reversing disc is clearance-fitted with the pump body cavity to ensure that the two can rotate relative to each other with a limited angle.

[0012] Furthermore, a locating pin is fixed on the commutator, which is inserted into the arc-shaped limiting groove of the pump rear cover. The central angle of the limiting groove is 180°, so that the maximum rotation angle of the commutator during forward and reverse rotation is half a revolution.

[0013] The inner rotor and outer rotor mesh with cycloidal tooth meshing, and the inner rotor has one less tooth than the outer rotor. The eccentricity is equal to the height of a single tooth. In the involute gear meshing structure, the difference in the number of teeth between the inner rotor and the outer rotor is designed according to the actual gear oil pump requirements, and the two adopt an eccentric internal meshing layout.

[0014] Preferably, the pump front cover and pump body are sealed by a first sealing ring, and a second sealing ring is provided between the pump shaft and the pump front cover and pump rear cover. Two fan-shaped oil grooves are symmetrically arranged on the inner side of the pump rear cover, respectively connecting the fixed oil suction port and oil outlet port. The geometric dimensions of the oil grooves match the flow channel window of the reversing disc. The transition area between the oil suction chamber and the oil outlet chamber is provided with a gradually curved surface or a flow guiding structure to reduce the turbulence of the oil flow.

[0015] The oil pump shaft input end is preferably coaxially connected to the gearbox input shaft of the ship's power system. When the ship's motor drives the propeller to rotate forward or reverse, the oil pump can continuously supply lubricating oil to the gearbox without switching pipelines, and the oil flow direction at the oil inlet and outlet is consistent with the direction of the external port.

[0016] When the pump shaft rotates forward, the outer rotor drives the reversing disc to rotate synchronously through friction. The locating pin slides to the left end of the limiting groove, and the oil suction chamber connects to the oil suction port through the left window of the reversing disc, while the oil discharge chamber discharges oil to the oil discharge port through the right window. The reversing disc is forced to stop due to obstruction at the right end of the limiting groove. When the input shaft rotates in reverse, the phase reversal of the outer rotor turns the original oil suction chamber into an oil discharge chamber. However, since the window position of the pump body is fixed, the actual oil discharge path still outputs from the original oil discharge port. At this time, the outer rotor and the reversing disc slide relative to each other, rotating 180° in the opposite direction. This maintains a constant oil circuit direction.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] This invention achieves automatic switching of the oil pump's suction and discharge chamber functions during forward and reverse rotation through the gap friction transmission between the reversing disc and the outer rotor, as well as the mechanical linkage structure between the positioning pin and the 180° limiting groove. This ensures that the flow direction of the oil inlet and outlet remains constant, overcoming the problems of complex structure and high failure rate caused by traditional solutions that rely on external reversing valves or electronic control systems.

[0019] This invention addresses the shortcomings of traditional bidirectional oil pumps, which rely on external valve groups and have poor adaptability. It innovatively designs a dynamic limit linkage mechanism for the reversing disc, achieving self-correction of the oil circuit through a purely mechanical structure. This enables the oil pump to supply oil when the oil pump shaft linked to the gearbox input shaft rotates left, and simultaneously drives the oil pump to supply oil when the oil pump shaft linked to the gearbox input shaft rotates right. This meets the requirements of current new energy sources for power propulsion on water, and satisfies the lubrication and cooling needs of the gearbox when driven by an electric motor.

[0020] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0021] Figures 1-4 This is a detailed illustration of the cycloidal rotor oil pump rotating to the left in an embodiment of this utility model.

[0022] in, Figure 1 This is a partially enlarged schematic diagram of the meshing structure of the inner and outer rotors when the cycloidal rotor oil pump rotates to the left in this embodiment of the present invention.

[0023] Figure 2 This is a cross-sectional view of the cycloidal rotor oil pump rotating to the left in this embodiment of the present invention.

[0024] Figure 3 is a diagram showing the positional relationship between the reversing disc and the positioning pin of the cycloidal rotor oil pump rotating to the left in an embodiment of this utility model.

[0025] Figure 4 This is a schematic diagram showing the position of the steering wheel positioning pin in the pump body and the oil flow path when the cycloidal rotor oil pump rotates to the left in this embodiment of the utility model.

[0026] Figures 5-7 This is a detailed illustration of the cycloidal rotor oil pump rotating to the right in an embodiment of this utility model.

[0027] in Figure 5 This is a partially enlarged structural diagram of the inner and outer rotors meshing when the cycloidal rotor oil pump rotates to the right in an embodiment of this utility model.

[0028] Figure 6 This is a diagram showing the positional relationship between the cycloidal rotor oil pump and the reversing disc and locating pin when rotating to the right in an embodiment of this utility model.

[0029] Figure 7 This is a schematic diagram showing the position of the steering wheel positioning pin in the pump body and the oil flow path when the cycloidal rotor oil pump rotates to the right in this embodiment of the present invention. It can be seen that... Figure 4 In comparison, the positions of the oil suction chamber and the oil outlet chamber are swapped, but the positions of the external oil suction port and the oil outlet port remain unchanged.

[0030] 1. Bolt; 2. Pump front cover; 3. Oil pump shaft; 4. First sealing ring; 5. Bearing; 6. Pump body; 7. Reversing plate; 8. Pump rear cover; 9. Bearing; 10. Inner rotor; 11. Second sealing ring; 12. Outer rotor; 13. Positioning pin; 14. Oil suction chamber; 141. Oil suction port; 15. Oil discharge chamber; 151. Oil discharge port; 16. Limiting groove. Detailed Implementation

[0031] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in different forms and is not limited to the embodiments described in the text. On the contrary, these embodiments are provided to make the disclosure of the utility model more thorough and comprehensive.

[0032] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical", "horizontal", "first", "second" and similar expressions used in this document are for illustrative purposes only.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] Example: This example provides a bidirectional cycloidal oil pump with a cycloidal structure. Through the linkage design of the reversing disc 7, the oil pump shaft 3, the inner rotor 10, and the outer rotor 12, the oil pump suction chamber 14 and the oil outlet chamber 15 are automatically switched when the input shaft rotates forward and backward, ensuring that the position and flow direction of the external suction port 141 and the oil outlet 151 are constant.

[0035] The pump assembly includes a sealed cavity formed by bolts 1 connecting the front cover 2, the pump body 6, and the rear cover 8. The pump shaft 3 is supported by the front bearing 5 and the rear bearing 9 and passes through the pump body. An inner rotor 10 with external teeth is fixed in the middle of the shaft, eccentrically meshing with an outer rotor 12 with internal teeth. A reversing disc 7 is fitted around the outer circumference of the outer rotor 12, and the two are clearance-fitted and can slide relative to each other. The positioning pin 13 of the reversing disc 7 is embedded in the 180° arc-shaped limiting groove 16 of the rear cover 8, limiting its rotation range. Symmetrical fan-shaped grooves, the suction chamber 14 and the discharge chamber 15, are arranged on the inner side of the rear cover 8 and are linked to the flow channel of the reversing disc 7. The opening direction of these grooves is dynamically adjusted according to the position of the reversing disc.

[0036] When the input shaft rotates forward, the outer rotor 12 rotates synchronously with the reversing disk 7, and the positioning pin 13 slides to the left end of the limiting groove 16, connecting the oil suction chamber 14 with the left oil suction port 141. In reverse rotation, the reversing disk 7 rotates 180° in the opposite direction with the outer rotor 12, stopping within the limiting groove at the position of the positioning pin. The oil chamber functions are interchanged, but the positions of the oil suction port 141 and the oil outlet 151 remain constant. This invention, through a purely mechanical reversing logic combined with a symmetrical oil chamber design, avoids the pipeline reversing problem caused by steering switching in traditional oil pumps, making it suitable for bidirectional drive scenarios such as marine power systems.

[0037] Please refer to this carefully. Figures 1-7 As shown, the oil pump shaft 3 passes through the pump body assembly. The inner rotor 10 adopts an external cycloidal tooth profile, for example, 6 teeth, while the inner gear ring of the outer rotor 12 adopts a cycloidal tooth profile with 7 teeth. The eccentricity between the two is equal to the single tooth height. Figure 1 The meshing point of the inner and outer rotors shifts periodically with eccentric rotation, and the volume of the inter-tooth cavity gradually expands from its minimum to its maximum to form an oil suction area, then compresses back to its minimum to complete the oil discharge. Figure 2 Cross-section. The reversing disc 7, which is slidably mounted on the outer circumference of the outer rotor 12, is clearance-fitted with the pump body. The locating pin 13 at the end of the reversing disc 7 is inserted into the 180° arc-shaped limiting groove 16 of the pump rear cover 8. This structure ensures that the reversing disc only rotates half a revolution during forward and reverse rotation to lock in position. Figure 3 The pump rear cover 8 has symmetrically designed fan-shaped grooves for the oil suction chamber 14 and the oil discharge chamber 15, with their openings corresponding to the left and right flow channel windows of the reversing disc 7. The transition area between the oil suction chamber 14 and the oil discharge chamber 15 is provided with a gradually curved surface to avoid pressure fluctuations caused by sudden changes in oil flow.

[0038] Furthermore, the pump front cover 2, pump body 6, and pump rear cover 8 form a multi-stage seal with the oil pump shaft 3 through the second sealing ring 11, a compact sealing design that reduces the risk of leakage.

[0039] Working principle:

[0040] (1) Forward rotation condition: Please refer to the appendix Figure 1-4 As shown, the input shaft drives the oil pump shaft 3 to rotate clockwise, and the inner rotor 10 drives the outer rotor 12 to rotate in the same direction. The reversing disk 7 rotates synchronously due to friction and is limited by the positioning pin 13, which has slid to the first position. At this time, the positioning pin 13 is located at the left end of the limiting groove 16. At this time, the inter-tooth cavity on the left side of the meshing point of the inner and outer rotors gradually expands, and the oil enters the left suction port 141 of the pump rear cover 8 through the window on the left side of the reversing disk 7; the right cavity is compressed, and the oil is forced into the right outlet port 151. Because the suction and discharge chambers are fixedly mapped to the external port, the oil path direction is constant.

[0041] (2) Reverse operation: Please refer to the appendix. Figure 5-7 As shown, when the input shaft rotates counterclockwise, the outer rotor 12 initially rotates in the opposite direction with the inner rotor 10. The reversing disk 7 rotates synchronously due to friction and is limited by the positioning pin 13, which has slid to the second position. At this time, the positioning pin 13 is located at the right end of the limiting groove 16. The outer rotor 12 and the reversing disk 7 generate sliding friction and rotate 180° in the opposite direction to adjust the meshing phase. At this time, the original right-side cavity becomes the oil suction area, but the reversing disk 7 is already positioned at the right end of the limiting groove. Its left window connects to the oil suction port 141 of the pump rear cover 8, and its right window connects to the oil outlet 151, maintaining the direction of the external oil passage.

[0042] The bidirectional cycloidal oil pump of this invention adjusts the meshing phase by rotating the outer rotor 12 in the opposite direction. It can achieve adaptive steering compensation without stopping or auxiliary control logic. In addition, the continuous volume change characteristics of the cycloidal rotor meshing reduce oil pressure fluctuations and achieve low-pulsation oil supply.

[0043] The present invention has been described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A bidirectional cycloidal oil pump, comprising: The pump body assembly, the inner rotor (10) and the outer rotor (12) installed in the pump body assembly, and the oil pump shaft (3) connected to the external power shaft are characterized in that: the inner rotor (10) is fixedly mounted on the oil pump shaft (3), the outer rotor (12) is sleeved on the inner rotor (10), the outer teeth of the inner rotor (10) mesh with the inner teeth of the outer rotor (12), and the inner teeth of the outer rotor (12) and the outer teeth of the inner rotor (10) form a cycloidal meshing structure; the reversing disk (7) is slidably provided on the outer rotor (12), the reversing disk (7) is provided with a positioning pin (13) on one end face, the pump body is provided with a limiting groove (16), and the positioning pin (13) slides in the limiting groove (16), and its sliding stroke is limited to 180°.

2. The bidirectional cycloidal oil pump according to claim 1, characterized in that, The difference in the number of teeth between the outer teeth of the inner rotor (10) and the inner teeth of the outer rotor (12) is at least 1.

3. The bidirectional cycloidal oil pump according to claim 1, characterized in that, The meshing centers of the inner rotor (10) and the outer rotor (12) are offset, and when they rotate relative to each other, the volume of the inter-tooth cavity is periodically changed to achieve oil suction and oil pressure.

4. The bidirectional cycloidal oil pump according to claim 1, characterized in that, The pump assembly includes a front cover (2), a pump body (6), and a rear cover (8), which are fixed together by bolts (1) to form a sealed cavity.

5. The bidirectional cycloidal oil pump according to claim 1, characterized in that, The oil pump shaft (3) is supported by the front bearing (5) and the rear bearing (9) and passes through the pump body.

6. The bidirectional cycloidal oil pump according to claim 2, characterized in that, It also includes an oil suction chamber (14), the shape of which is adapted to the meshing area of ​​the inner rotor (10) and the outer rotor (12), and the connection between the oil suction chamber (14) and the oil outlet chamber (15) adopts a gradual transition design.

7. The bidirectional cycloidal oil pump according to claim 6, characterized in that, The oil suction chamber (14) and the oil outlet chamber (15) are symmetrically distributed fan-shaped grooves, and the rotation of the commutator (7) is on the fan-shaped grooves.

8. The bidirectional cycloidal oil pump according to claim 1, characterized in that, The pump front cover (2) is sealed to the pump body (6) by a first sealing ring (4), and a second sealing ring (11) is provided between the oil pump shaft (3) and the pump front cover (2) and the pump rear cover (8).

9. The bidirectional cycloidal oil pump according to any one of claims 1-8, characterized in that, The oil pump is integrated into the ship's power system and is coaxially connected to the gearbox input shaft or the motor drive shaft.

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