Underground generator rotor assembly structure

Abstract

The utility model discloses an underground generator rotor assembly structure, which relates to the field of underground generators and comprises a rotor shaft with a hollow structure, the rotor shaft is a step shaft, the top end of the rotor shaft is a hexagonal shaft structure, and an inner magnetic coupling body assembly is arranged outside the hexagonal shaft. The motor further comprises a rotor shaft magnet assembly arranged below the inner magnetic coupling body assembly, bearing assemblies are arranged above and below the rotor shaft magnet assembly, and when the inner magnetic coupling body assembly rotates, the rotor shaft, the rotor shaft magnet assembly and the bearing assemblies rotate synchronously. According to the utility model, through the combined arrangement of the internal magnetic coupling magnet assembly, the rotor shaft magnet assembly and the rotor shaft, a plurality of internal magnetic coupling magnets and rotor shaft magnets can be limited, so that the stability of the two groups of magnets is ensured; the internal magnetic coupling magnets and the rotor shaft magnets are effectively prevented from deviating and throwing under the action of centrifugal force generated by high-speed rotation, and the running stability of the whole rotor assembly structure is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of downhole generators, and in particular to a rotor assembly structure for a downhole generator. Background Technology

[0002] In the development of oil and gas, measurement-while-drilling (MWD) instruments are indispensable measuring equipment during drilling. These instruments require power from a downhole turbine generator. The working principle of the downhole turbine generator is that the mud drives the external turbine rotor of the generator to rotate, which, through a magnetic coupling mechanism, drives the internal rotor of the generator to rotate. The rotating rotor cuts the magnetic induction lines of the stator coil, generating alternating current.

[0003] In the working environment of underground development, vibrations are easily generated in the external environment as machinery operates continuously, thus affecting the stability of the external environment. The generator rotor assembly located underground is mostly in a high-speed operating state. Therefore, based on this working environment, the underground generator rotor assembly is easily affected by the external environment during operation, which leads to a decrease in its stability and easily affects the stability of the generator during operation. Utility Model Content

[0004] To address the aforementioned issues, this application provides a rotor assembly structure for an underground generator.

[0005] To achieve the above objectives, this application provides the following technical solution: a rotor assembly structure for an underground generator, including a rotor shaft with a hollow structure, the rotor shaft being a stepped shaft design, and the top of the rotor shaft having a hexagonal shaft structure, with an internal magnetic coupling assembly provided outside the hexagonal shaft.

[0006] It also includes a rotor shaft magnet assembly located below the inner magnetic coupler assembly. Bearing assemblies are provided above and below the rotor shaft magnet assembly. When the inner magnetic coupler assembly rotates, the rotor shaft, rotor shaft magnet assembly and bearing assembly rotate synchronously.

[0007] Furthermore, the inner magnetic coupling assembly includes multiple inner magnetic coupling magnets, inner magnetic coupling outer retaining rings respectively interference-fitted onto the inner magnetic coupling magnets above and below the inner magnetic coupling magnets, inner magnetic coupling inner retaining rings, and an inner magnetic coupling magnet outer cover fixed to the outside of the inner magnetic coupling magnets.

[0008] The hexagonal shaft is provided with a first mating surface and a second mating surface that are adapted to the outer retaining ring of the inner magnetic coupling and the inner retaining ring of the inner magnetic coupling.

[0009] Furthermore, the number of magnets in the internal magnetic coupling magnet is even, and the magnetic field directions of two adjacent internal magnetic coupling magnets are opposite.

[0010] Furthermore, the rotor shaft magnet assembly includes multiple rotor magnets, magnetic isolation strips disposed within two adjacent rotor magnets, external retaining rings of the rotor magnets disposed above and below the rotor magnets, internal retaining rings of the rotor magnets, and an outer cover of the rotor magnets fixed to the outside of the rotor magnets.

[0011] The rotor shaft is provided with multiple adhesive surfaces adapted to the rotor magnets, and there is a mounting groove between two adjacent adhesive surfaces that is recessed toward the central axis of the rotor shaft. The magnetic shielding strips are all located inside the mounting groove.

[0012] Furthermore, the number of magnets in the rotor magnet is even, and the magnetic field directions of two adjacent rotor magnets are opposite.

[0013] Furthermore, the bearing assembly located above the rotor shaft magnet assembly consists of an upper bearing disposed outside the rotor shaft and a first bearing retaining ring disposed below the upper bearing. The rotor shaft is provided with an upper end shoulder that abuts against the top end of the upper bearing and a bearing mounting surface that is assembled with the upper bearing.

[0014] Furthermore, the bearing assembly located above the rotor shaft magnet assembly consists of a lower bearing disposed outside the rotor shaft and a second bearing retaining ring disposed below the lower bearing. The rotor shaft is provided with a lower end shoulder that abuts against the lower bearing and a bearing mounting surface that assembles with the lower bearing.

[0015] In summary, the technical effects and advantages of this utility model are as follows:

[0016] This invention, through the combination of the internal magnetic coupling body assembly, the rotor shaft magnet assembly, and the rotor shaft, can limit the movement of multiple internal magnetic coupling magnets and rotor shaft magnets, ensuring the stability of the two sets of magnets. It effectively prevents the multiple internal magnetic coupling magnets and rotor shaft magnets from shifting or being thrown off under the centrifugal force generated by high-speed rotation, ensuring the stability of the entire rotor assembly structure and thus improving the stability of power generation operation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a cross-sectional structural diagram of the present invention.

[0019] Figure 2 This is a three-dimensional structural diagram of the present invention.

[0020] Figure 3This is a schematic diagram of the internal magnetic coupler assembly of this utility model after being cut open.

[0021] Figure 4 This is a schematic diagram of the rotor shaft magnet assembly of this utility model after being cut open.

[0022] In the diagram: 1. Rotor shaft; 11. Hexagonal shaft; 12. First mating surface; 13. Second mating surface; 14. Upper shaft shoulder; 15. Bearing mounting surface one; 16. Mounting groove; 17. Adhesive surface; 18. Lower shaft shoulder; 19. Bearing mounting surface two; 21. Inner magnetic coupling magnet; 22. Inner magnetic coupling outer retaining ring; 23. Inner magnetic coupling inner retaining ring; 24. Inner magnetic coupling magnet outer cover; 31. Rotor magnet; 32. Magnetic isolation strip; 33. Rotor magnet outer retaining ring; 34. Rotor magnet inner retaining ring; 35. Rotor magnet outer cover; 41. Upper bearing; 42. Lower bearing; 43. First bearing retaining ring; 44. Second bearing retaining ring. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] Example: Reference Figure 1-2 The diagram shows a rotor assembly structure for an underground generator, including a hollow rotor shaft 1. The rotor shaft 1 is designed as a stepped shaft, and the top of the rotor shaft 1 is a hexagonal shaft 11 structure. An internal magnetic coupling assembly is provided outside the hexagonal shaft 11.

[0025] It also includes a rotor shaft magnet assembly located below the inner magnetic coupler assembly. Bearing assemblies are located above and below the rotor shaft magnet assembly. When the inner magnetic coupler assembly rotates, the rotor shaft magnet assembly and bearing assemblies rotate synchronously under the connection of the rotor shaft 1. The rotating rotor shaft magnet assembly cuts the magnetic induction lines of the stator coil, generating alternating current.

[0026] like Figure 3 As shown, the inner magnetic coupling assembly includes multiple inner magnetic coupling magnets 21, inner magnetic coupling outer retaining rings 22 and inner magnetic coupling inner retaining rings 23 respectively interference-fitted onto the upper and lower parts of the inner magnetic coupling magnets 21, and an inner magnetic coupling magnet outer cover 24 fixed to the outside of the inner magnetic coupling magnets 21. The inner magnetic coupling magnet outer cover 24 is made of non-magnetic stainless steel and has a thin-walled structure.

[0027] The hexagonal shaft 11 is provided with a first mating surface 12 and a second mating surface 13 that are adapted to the outer retaining ring 22 and the inner retaining ring 23 of the inner magnetic coupling.

[0028] The inner magnetic coupling magnet 21 is made of cobalt-32 permanent magnet with high temperature resistance, high magnetic energy level and coercivity. The number of magnets in the inner magnetic coupling magnet 21 is even, and the magnetic field directions of two adjacent inner magnetic coupling magnets 21 are opposite.

[0029] like Figure 3 As shown, in the actual installation process, firstly, the inner magnetic coupling inner retaining ring 23 is interference-fitted with the second mating surface 13 on the hexagonal shaft 11, and the shaft shoulder is installed in place. Six inner magnetic coupling magnets 21 are prepared, of which three magnets are magnetized from the inside out as N / S poles, and the other three magnets are magnetized from the inside out as SN poles. The six inner magnetic coupling magnets are bonded to the hexagonal shaft 11 using high-temperature epoxy adhesive, with magnets of different magnetic field directions arranged adjacent to each other. Ensure that one end face of the magnet abuts against the inner magnetic coupling inner retaining ring 23.

[0030] Next, the outer retaining ring 22 of the inner magnetic coupling is interference-fitted to the first mating surface 12 on the hexagonal shaft 11, ensuring that one end face of the outer retaining ring 22 abuts against the other end face of the magnet. Finally, high-temperature epoxy adhesive is applied to the outer ring of the inner magnetic coupling magnet, and the outer cover 24 of the inner magnetic coupling magnet is fitted onto the inner magnetic coupling magnet 21, with its end face abutting against the shoulder face of the inner retaining ring. This avoids the risk of the inner magnetic coupling magnet 21 being thrown out due to centrifugal force at high speeds, ensuring the stability of the inner magnetic coupling assembly during operation.

[0031] like Figure 4 As shown, the rotor shaft magnet assembly includes multiple rotor magnets 31, magnetic isolation strips 32 disposed within two adjacent rotor magnets 31, external retaining rings 33 disposed above and below the rotor magnets 31, internal retaining rings 34 disposed within the rotor magnets, and an outer cover 35 fixed to the outside of the rotor magnets 31. The outer cover 35 is made of non-magnetic stainless steel and has a thin-walled structure.

[0032] The rotor shaft 1 has multiple bonding surfaces 17 that are adapted to the rotor magnets 31. Between two adjacent bonding surfaces 17, there is a recessed mounting groove 16 facing the central axis of the rotor shaft 1. The magnetic isolation strips 32 are all disposed inside the mounting grooves 16. The setting of the magnetic isolation strips 32 can avoid mutual interference between multiple rotor magnets 1 and ensure the stability of the magnetic field.

[0033] The rotor magnet 31 is made of cobalt permanent magnet with high temperature resistance, high magnetic energy level and coercivity. The number of magnets in the rotor magnet 31 is even, and the magnetic field directions of two adjacent rotor magnets 31 are opposite.

[0034] As attached Figure 4As shown, in the actual installation process, the inner retaining ring 34 of the rotor magnet is first interference-fitted to the mating surface of the rotor shaft 1. Then, four magnetic isolation strips 32 are interference-fitted into the mounting groove 16 on the outer circumference of the rotor shaft 1. There are four rotor magnets 31, two of which are magnetized from the inside out as N / S poles, and the other two are magnetized from the inside out as SN poles. The four rotor magnets 31 are bonded to the bonding surface 17 with high-temperature epoxy adhesive, with magnets of different magnetic field directions arranged adjacent to each other. This ensures that one end face of the rotor magnet 31 abuts against the inner retaining ring 34 of the rotor magnet.

[0035] Next, the outer retaining ring 33 of the rotor magnet is interference-fitted to the rotor shaft 1, ensuring that one end face of the outer retaining ring 33 abuts against the other end face of the rotor magnet 31. Finally, high-temperature epoxy adhesive is applied to the outer ring of the rotor magnet 31, and the outer cover of the rotor magnet is fitted onto the rotor magnet, with its end face abutting against the shoulder face of the inner retaining ring of the rotor magnet. This avoids the risk of the rotor magnet 31 being thrown out due to centrifugal force at high speeds, ensuring the stability of the rotor shaft magnet assembly during operation.

[0036] like Figure 1 As shown, the bearing assembly located above the rotor shaft magnet assembly consists of an upper bearing 41 located outside the rotor shaft 1 and a first bearing retaining ring 43 located below the upper bearing 41. The rotor shaft 1 is provided with an upper end shoulder 14 that abuts against the top end of the upper bearing 41 and a bearing mounting surface 15 that is assembled with the upper bearing 41.

[0037] The bearing assembly located above the rotor shaft magnet assembly consists of a lower bearing 42 located outside the rotor shaft 1 and a second bearing retaining ring 44 located below the lower bearing 42. The rotor shaft 1 is provided with a lower end shoulder 18 that abuts against the lower bearing 42 and a bearing mounting surface 19 that is assembled with the lower bearing 42.

[0038] During the installation of the bearing assembly, the upper bearing 41 is first interference-fitted onto the bearing mounting surface 15, abutting against the upper shaft shoulder 14. Then, the first bearing retaining ring 43 is installed below the upper bearing 41 to limit the upper bearing 41 and maintain its stability.

[0039] Subsequently, the lower bearing 42 is installed on the bearing mounting surface 19, abutting against the lower end shoulder 18. Then, the second bearing retaining ring 44 is installed at the bottom end of the lower bearing 42 to limit the lower bearing 42 and maintain its stability. Both the upper bearing 41 and the lower bearing 42 are deep groove ball bearings capable of achieving high speeds and withstanding radial and axial loads.

[0040] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A rotor assembly structure for an underground generator, characterized in that: It includes a hollow rotor shaft (1), which is designed as a stepped shaft, and the top of the rotor shaft (1) is a hexagonal shaft (11) structure, with an inner magnetic coupling assembly on the outside of the hexagonal shaft (11); It also includes a rotor shaft magnet assembly located below the inner magnetic coupler assembly. The rotor shaft magnet assembly is provided with bearing assemblies above and below it. When the inner magnetic coupler assembly rotates, the rotor shaft (1), the rotor shaft magnet assembly and the bearing assembly rotate synchronously.

2. The downhole generator rotor assembly structure according to claim 1, characterized in that: The inner magnetic coupling assembly includes multiple inner magnetic coupling magnets (21), inner magnetic coupling outer retaining rings (22) respectively interference-fitted on the upper and lower sides of the inner magnetic coupling magnets (21), inner magnetic coupling inner retaining rings (23), and inner magnetic coupling magnet outer cover (24) fixed on the outside of the inner magnetic coupling magnets (21). The hexagonal shaft (11) is provided with a first mating surface (12) and a second mating surface (13) that are adapted to the outer retaining ring (22) and the inner retaining ring (23) of the inner magnetic coupling.

3. The downhole generator rotor assembly structure according to claim 2, characterized in that: The number of magnets in the internal magnetic coupling magnet (21) is even, and the magnetic field directions of two adjacent internal magnetic coupling magnets (21) are opposite.

4. The downhole generator rotor assembly structure according to claim 1, characterized in that: The rotor shaft magnet assembly includes multiple rotor magnets (31), magnetic isolation strips (32) disposed in two adjacent rotor magnets (31), external retaining rings (33) of the rotor magnets disposed on the upper and lower sides of the rotor magnets (31), internal retaining rings (34) of the rotor magnets, and an outer cover (35) of the rotor magnets fixed to the outside of the rotor magnets (31). The rotor shaft (1) is provided with multiple adhesive surfaces (17) that are adapted to the rotor magnet (31). Between two adjacent adhesive surfaces (17), there is a mounting groove (16) recessed towards the central axis of the rotor shaft (1). The magnetic strips (32) are all located inside the mounting groove (16).

5. The downhole generator rotor assembly structure according to claim 4, characterized in that: The number of rotor magnets (31) is even, and the magnetic field directions of two adjacent rotor magnets (31) are opposite.

6. The downhole generator rotor assembly structure according to claim 1, characterized in that: The bearing assembly located above the rotor shaft magnet assembly consists of an upper bearing (41) located outside the rotor shaft (1) and a first bearing retainer (43) located below the upper bearing (41). The rotor shaft (1) is provided with an upper end shoulder (14) that abuts against the top end of the upper bearing (41) and a bearing mounting surface (15) that is assembled with the upper bearing (41).

7. The downhole generator rotor assembly structure according to claim 1, characterized in that: The bearing assembly located above the rotor shaft magnet assembly consists of a lower bearing (42) located outside the rotor shaft (1) and a second bearing retainer (44) located below the lower bearing (42). The rotor shaft (1) is provided with a lower end shoulder (18) that abuts against the lower bearing (42) and a bearing mounting surface (19) that is assembled with the lower bearing (42).

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