Downhole speed reducer

Abstract

The invention relates to the technical field of speed reducers, in particular to an underground speed reducer which comprises a shell, a sealing cavity is formed in the shell, a first annular sliding sleeve and a second annular sliding sleeve are arranged at the two ends of the sealing cavity respectively, a first piston is slidably and hermetically connected into the first annular sliding sleeve, and a first spring is axially arranged in the first annular sliding sleeve; the input shaft penetrates through the middle of the first piston, a second piston is connected into the second annular sliding sleeve in a sliding and sealing mode, a second spring is arranged in the second annular sliding sleeve in the axial direction, and the output shaft penetrates through the middle of the second piston. When the pressure difference is generated between the sealing cavity and the outside of the shell, the first piston and the second piston can compress or enlarge the space of the sealing cavity, then the pressure in the sealing cavity is increased or reduced till the pressure inside and outside the speed reducer is balanced, the working performance and reliability of the speed reducer in the underground severe environment are improved, and the service life of the speed reducer is prolonged. Pressure difference inside and outside the speed reducer can be balanced, and sealing performance is good.

Description

Technical Field

[0001] The present invention relates to the technical field of speed reducers, and in particular to an underground speed reducer. Background Art

[0002] In the field of modern industrial production and mining, reducers, as an important part of mechanical equipment, are widely used in various occasions where speed reduction and torque increase are required. Especially in underground working environments, reducers must not only withstand harsh working conditions, but also ensure long-term stable operation. However, existing reducers face many challenges in underground applications.

[0003] In the underground environment, due to the presence of a large amount of dust and moisture, and the high external pressure, higher requirements are placed on the sealing performance of the reducer. At the same time, due to the high temperature underground, the pressure of the lubricating oil in the reducer will also increase. The sealing structure of the traditional reducer is relatively simple. When the external pressure is greater than the pressure inside the reducer, external pollutants can easily invade the reducer, causing problems such as lubricating oil pollution and increased wear of parts. When the internal pressure of the reducer is greater than the external pressure, the lubricating oil inside the reducer is easy to seep out. The existing reducer cannot balance the pressure difference inside and outside the reducer, and the reliability is poor, making it difficult to ensure the working performance of the reducer. Summary of the invention

[0004] The present invention aims to at least solve the technical problems existing in the prior art. To this end, the present invention proposes a downhole reducer, which improves the working performance and reliability of the reducer in the harsh environment of the downhole, can balance the pressure difference inside and outside the reducer, has good sealing performance, and ensures the cleanliness of the inside of the reducer.

[0005] According to some embodiments of the present invention, a downhole reducer comprises a housing, an input shaft and an output shaft are respectively provided at two ends of the housing, a planetary gear reduction mechanism is provided between the input shaft and the output shaft, the input shaft is connected to the input end of the planetary gear reducer, and the output shaft is connected to the output end of the planetary gear reduction mechanism, a sealing chamber is provided inside the housing, the planetary gear reduction mechanism is located in the sealing chamber, a first annular sleeve and a second annular sleeve are respectively provided at two ends of the sealing chamber, a first piston is slidingly and sealably connected in the first annular sleeve, a first spring is axially provided in the first annular sleeve, the first spring is connected to the first piston, the input shaft is penetrated through the middle part of the first piston, the second annular sleeve is slidingly and sealably connected in the second piston, a second spring is axially provided in the second annular sleeve, the second spring is connected to the second piston, and the output shaft is penetrated through the middle part of the second piston.

[0006] A downhole speed reducer according to some embodiments of the present invention has at least the following beneficial effects:

[0007] The present invention is connected with the output end of the planetary gear reduction mechanism through an output shaft, a sealing chamber is arranged inside the shell, the planetary gear reduction mechanism is located in the sealing chamber, lubricating oil is injected into the sealing chamber before use to ensure the performance of the reducer, and at the same time, a first annular sleeve and a second annular sleeve are arranged, a first piston is slidingly and sealably connected in the first annular sleeve, a first spring is axially arranged in the first annular sleeve, the first spring is connected to the first piston, an input shaft is passed through the middle of the first piston, a second piston is slidingly and sealably connected in the second annular sleeve, a second spring is axially arranged in the second annular sleeve, the second spring is connected to the second piston, and the output shaft is passed through the middle of the second piston. When a pressure difference is generated between the sealing chamber and the outside of the shell, the first piston and the second piston will move in the first annular sleeve and the second annular sleeve respectively, compressing or enlarging the space of the sealing chamber, thereby increasing or decreasing the pressure in the sealing chamber until the pressure inside and outside the reducer is balanced. The present invention improves the working performance and reliability of the reducer in a harsh underground environment, can balance the pressure difference inside and outside the reducer, has good sealing performance, and ensures the cleanliness inside the reducer.

[0008] According to a downhole reducer of some embodiments of the present invention, a first connecting block is protruded on the inner wall of one end of the first annular sleeve, and two ends of the first spring are respectively connected to the first connecting block and the first piston.

[0009] According to a downhole reducer of some embodiments of the present invention, a step portion is provided at one end of the input shaft close to the planetary gear reduction mechanism, the step portion is located on a side of the first annular sleeve close to the planetary gear reduction mechanism, and the first piston is located between the step portion and the first connecting block.

[0010] According to a downhole reducer of some embodiments of the present invention, a second connecting block is protruded on the inner wall of one end of the second annular sleeve, and two ends of the second spring are respectively connected to the second connecting block and the second piston.

[0011] According to a downhole reducer of some embodiments of the present invention, a retaining spring is provided on the output shaft, the retaining spring is located at an end of the second annular sleeve away from the second connecting block, and the second piston is located between the retaining spring and the second connecting block.

[0012] According to a downhole reducer of some embodiments of the present invention, an abutment plate is slidably provided in the second annular sleeve, the abutment plate is located between the second spring and the second piston, and the second spring is connected to the abutment plate.

[0013] According to some embodiments of the present invention, a downhole reducer is provided with a first bearing and a second bearing on the inner wall of the housing, the input shaft is passed through the first bearing, the output shaft is passed through the second bearing, and the first bearing and the second bearing are both located in the sealing cavity.

[0014] According to some embodiments of the present invention, a downhole reducer, the housing includes a first shell, a second shell and a third shell connected in sequence, the first bearing is arranged on the inner wall of the first shell, the planetary gear reduction mechanism is located in the second shell, and the second bearing is arranged on the inner wall of the third shell.

[0015] According to some embodiments of the present invention, a downhole reducer, the planetary gear reduction mechanism includes a driving wheel, three planetary wheels and a ring gear, the middle part of the input shaft is connected to the driving wheel, the three planetary wheels are evenly distributed on the outer periphery of the driving wheel, the ring gear is sleeved on the outer periphery of the three planetary gears, the driving wheel is meshed with the three planetary wheels, the three planetary wheels are all meshed with the ring gear, the middle parts of the three planetary wheels are rotatably connected to the output shaft, and the ring gear is arranged on the inner wall of the housing.

[0016] According to a downhole reducer in some embodiments of the present invention, an oil injection hole is provided on the housing, and the oil injection hole is communicated with the sealing cavity.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0020] Figure 2 It is a cross-sectional view of an embodiment of the present invention.

[0021] Figure 3 4 is a cross-sectional view of a planetary gear reduction mechanism according to an embodiment of the present invention.

[0022] Figure numerals: 1, housing, 2, input shaft, 3, output shaft, 4, planetary gear reduction mechanism, 5, sealing chamber, 6, first annular sleeve, 7, second annular sleeve, 8, first piston, 9, first spring, 10, second piston, 11, second spring, 12, first connecting block, 13, step portion, 14, second connecting block, 15, retaining spring, 16, abutment plate, 17, first bearing, 18, second bearing, 19, first outer shell, 20, second outer shell, 21, third outer shell, 22, driving wheel, 23, planetary gear, 24, ring gear, 25, oil filling hole. DETAILED DESCRIPTION

[0023] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0024] In the description of the present invention, it should be understood that the descriptions involving orientations, such as up, down, left, right, front, back, etc., and the orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the modules or components referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In the description of the present invention, if there is a description of first and second, it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0027] like Figure 1-Figure 3 As shown, an embodiment of the present invention provides a downhole speed reducer.

[0028] A downhole reducer comprises a housing 1, wherein an input shaft 2 and an output shaft 3 are respectively arranged at both ends of the housing 1, a planetary gear reduction mechanism 4 is arranged between the input shaft 2 and the output shaft 3, the input shaft 2 is connected to the input end of the planetary gear reduction mechanism 4, and the output shaft 3 is connected to the output end of the planetary gear reduction mechanism 4, a sealing chamber 5 is arranged inside the housing 1, and the planetary gear reduction mechanism 4 is located in the sealing chamber 5, and a first annular sleeve 6 and a second annular sleeve 7 are respectively arranged at both ends of the sealing chamber 5, a first piston 8 is slidingly and sealably connected in the first annular sleeve 6, a first spring 9 is axially arranged in the first annular sleeve 6, and the first spring 9 is connected to the first piston 8, the input shaft 2 is penetrated in the middle of the first piston 8, a second piston 10 is slidingly and sealably connected in the second annular sleeve 7, a second spring 11 is axially arranged in the second annular sleeve 7, and the second spring 11 is connected to the second piston 10, and the output shaft 3 is penetrated in the middle of the second piston 10.

[0029] The present invention is connected with the output end of the planetary gear reduction mechanism 4 through the output shaft 3, the interior of the housing 1 is provided with a sealed chamber 5, the planetary gear reduction mechanism 4 is located in the sealed chamber 5, and lubricating oil is injected into the sealed chamber 5 before use to ensure the performance of the reducer, and at the same time, a first annular sleeve 6 and a second annular sleeve 7 are provided, a first piston 8 is connected in a sliding seal in the first annular sleeve 6, a first spring 9 is axially provided in the first annular sleeve 6, and the first spring 9 is connected to the first piston 8, the input shaft 2 is passed through the middle of the first piston 8, a second piston 10 is connected in a sliding seal in the second annular sleeve 7, and a second piston 10 is connected in the second annular sleeve 7. A second spring 11 is axially arranged, the second spring 11 is connected to the second piston 10, and the output shaft 3 is passed through the middle of the second piston 10. When a pressure difference is generated between the sealing chamber 5 and the outside of the housing 1, the first piston 8 and the second piston 10 will move in the first annular sleeve 6 and the second annular sleeve 7 respectively, compressing or enlarging the space of the sealing chamber 5, thereby increasing or decreasing the pressure in the sealing chamber 5 until the pressure inside and outside the reducer is balanced. The present invention improves the working performance and reliability of the reducer in harsh underground environments, can balance the pressure difference inside and outside the reducer, has good sealing performance, and ensures the cleanliness of the inside of the reducer.

[0030] In the downhole reducer described in this embodiment, a first connecting block 12 is convexly provided on the inner wall of one end of the first annular sleeve 6, and the two ends of the first spring 9 are respectively connected to the first connecting block 12 and the first piston 8. Specifically, by providing the first connecting block 12 on the inner wall of one end of the first annular sleeve 6, and connecting the two ends of the first spring 9 to the first connecting block 12 and the first piston 8, the axial support effect of the first spring 9 on the first piston 8 can be ensured, and good sealing performance can be maintained.

[0031] In the downhole speed reducer described in this embodiment, a step portion 13 is provided at one end of the input shaft 2 close to the planetary gear reduction mechanism 4, the step portion 13 is located on the side of the first annular sleeve 6 close to the planetary gear reduction mechanism 4, and the first piston 8 is located between the step portion 13 and the first connecting block 12. Specifically, by providing the step portion 13 at one end of the input shaft 2 close to the planetary gear reduction mechanism 4 and placing the first piston 8 between the step portion 13 and the first connecting block 12, the step portion 13 can be used to limit the maximum displacement of the first piston 8, thereby preventing the piston from over-displacement and causing sealing failure, and also helps to improve the axial positioning accuracy of the input shaft 2.

[0032] In the downhole speed reducer described in this embodiment, a second connecting block 14 is convexly provided on the inner wall of one end of the second annular sleeve 7, and the two ends of the second spring 11 are respectively connected to the second connecting block 14 and the second piston 10. Specifically, by providing the second connecting block 14 on the inner wall of one end of the second annular sleeve 7, and connecting the two ends of the second spring 11 to the second connecting block 14 and the second piston 10, the axial support effect of the second spring 11 on the second piston 10 can be ensured, and good sealing performance can be maintained.

[0033] In the downhole speed reducer described in this embodiment, a retaining spring 15 is provided on the output shaft 3, the retaining spring 15 is located at the end of the second annular sleeve 7 away from the second connecting block 14, and the second piston 10 is located between the retaining spring 15 and the second connecting block 14. Specifically, by providing the retaining spring 15 on the output shaft 3 and placing it at the end of the second annular sleeve 7 away from the second connecting block 14, the second piston 10 is restricted between the retaining spring 15 and the second connecting block 14, the retaining spring 15 can be used to limit the maximum displacement of the second piston 10, prevent the piston from over-displacement and cause sealing failure, and also help to improve the axial positioning accuracy of the output shaft 3.

[0034] In the downhole speed reducer described in this embodiment, an abutment plate 16 is slidably provided in the second annular sleeve 7, the abutment plate 16 is located between the second spring 11 and the second piston 10, and the second spring 11 is connected to the abutment plate 16. Specifically, since one end of the output shaft 3 is more susceptible to the risk of intrusion of external mud, sand and water vapor in actual work, by providing the abutment plate 16 in the second annular sleeve 7 and placing it between the second spring 11 and the second piston 10, the contact stability between the second piston 10 and the second spring 11 can be further enhanced, the stability of the second piston 10 when sliding can be ensured, and the sealing effect can be improved.

[0035] In the downhole reducer described in this embodiment, a first bearing 17 and a second bearing 18 are arranged on the inner wall of the housing 1, the input shaft 2 is inserted through the first bearing 17, and the output shaft 3 is inserted through the second bearing 18, and the first bearing 17 and the second bearing 18 are both located in the sealed cavity 5. Specifically, by arranging the first bearing 17 and the second bearing 18 on the inner wall of the housing 1, and inserting the input shaft 2 and the output shaft 3 through these two bearings respectively, good radial support can be provided when the input shaft 2 and the output shaft 3 rotate, the radial runout of the shaft can be reduced, and the rotation stability and bearing life can be improved. It can be understood that in some embodiments, two first bearings 17 and two second bearings 18 are arranged in parallel.

[0036] In the downhole reducer described in this embodiment, the housing 1 includes a first housing 19, a second housing 20 and a third housing 21 connected in sequence, the first bearing 17 is arranged on the inner wall of the first housing 19, the planetary gear reduction mechanism 4 is located in the second housing 20, and the second bearing 18 is arranged on the inner wall of the third housing 21. Specifically, by dividing the housing 1 into the first housing 19, the second housing 20 and the third housing 21, and respectively arranging the first bearing 17, the planetary gear reduction mechanism 4 and the second bearing 18, a modular design can be achieved, which is convenient for assembly and maintenance of the reducer, and also convenient for replacement or inspection of internal parts.

[0037] In the downhole reducer described in this embodiment, the planetary gear reduction mechanism 4 includes a driving wheel 22, three planetary wheels 23 and a ring gear 24, the middle part of the input shaft 2 is connected to the driving wheel 22, the three planetary wheels 23 are evenly spaced on the outer periphery of the driving wheel 22, the ring gear 24 is sleeved on the outer periphery of the three planetary gears 23, the driving wheel 22 is meshed with the three planetary wheels 23, the three planetary wheels 23 are all meshed with the ring gear 24, the middle part of the three planetary wheels 23 is rotatably connected to the output shaft 3, and the ring gear 24 is arranged on the inner wall of the housing 1. Specifically, by setting a planetary gear reduction mechanism 4, including a driving wheel 22, three planetary wheels 23 and a ring gear 24, and connecting the input shaft 2 with the driving wheel 22, the three planetary wheels 23 are evenly spaced on the outer periphery, meshing with the driving wheel 22 and the ring gear 24, efficient torque transmission can be achieved, and at the same time, the uniform distribution of the planetary wheels 23 ensures the stability of the reducer operation and reduces vibration and noise.

[0038] It can be understood that the components inside the reducer that need to be soaked in lubricating oil are the first bearing 17, the second bearing 18 and the planetary gear reduction mechanism 4. The first bearing 17, the second bearing 18 and the planetary gear reduction mechanism 4 are all arranged in the sealed cavity 5. There is a gap between the balls of the first bearing 17 and the second bearing 18 to allow the lubricating oil to pass through. There is a gap between the planetary wheels 23 of the planetary gear reduction mechanism 4 to allow the lubricating oil to pass through. Therefore, the internal lubricating oil flows in the sealed cavity 5 and can soak the first bearing 17, the second bearing 18 and the planetary gear reduction mechanism 4 at the same time. The structural design of the present invention is ingenious, which maximizes the guarantee that all components that need lubrication can work stably.

[0039] In the downhole reducer described in this embodiment, an oil filling hole 25 is provided on the housing 1, and the oil filling hole 25 is communicated with the sealing cavity 5. Specifically, by providing the oil filling hole 25 on the housing 1 and communicating with the sealing cavity 5, the reducer can be easily refueled or lubricated.

[0040] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A downhole reducer, characterized in that: It includes a shell, an input shaft and an output shaft are respectively provided at two ends of the shell, a planetary gear reduction mechanism is provided between the input shaft and the output shaft, the input shaft is connected to the input end of the planetary gear reducer, and the output shaft is connected to the output end of the planetary gear reduction mechanism, a sealing chamber is provided inside the shell, the planetary gear reduction mechanism is located in the sealing chamber, a first annular sleeve and a second annular sleeve are respectively provided at two ends of the sealing chamber, a first piston is slidingly and sealably connected in the first annular sleeve, a first spring is axially provided in the first annular sleeve, the first spring is connected to the first piston, the input shaft is penetrated through the middle part of the first piston, a second piston is slidingly and sealably connected in the second annular sleeve, a second spring is axially provided in the second annular sleeve, the second spring is connected to the second piston, and the output shaft is penetrated through the middle part of the second piston.

2. A downhole speed reducer according to claim 1, characterized in that: A first connecting block is protrudingly provided on the inner wall of one end of the first annular sleeve, and two ends of the first spring are respectively connected to the first connecting block and the first piston.

3. A downhole speed reducer according to claim 2, characterized in that: A step portion is provided at one end of the input shaft close to the planetary gear reduction mechanism. The step portion is located on a side of the first annular sleeve close to the planetary gear reduction mechanism. The first piston is located between the step portion and the first connecting block.

4. A downhole speed reducer according to claim 1, characterized in that: A second connecting block is protrudingly provided on the inner wall of one end of the second annular sleeve, and two ends of the second spring are respectively connected to the second connecting block and the second piston.

5. A downhole speed reducer according to claim 4, characterized in that: The output shaft is provided with a retaining spring, the retaining spring is located at an end of the second annular sleeve away from the second connecting block, and the second piston is located between the retaining spring and the second connecting block.

6. A downhole speed reducer according to claim 5, characterized in that: An abutment plate is slidably disposed in the second annular sliding sleeve. The abutment plate is located between the second spring and the second piston. The second spring is connected to the abutment plate.

7. The downhole reducer according to claim 1, characterized in that: A first bearing and a second bearing are arranged on the inner wall of the housing, the input shaft is passed through the first bearing, the output shaft is passed through the second bearing, and both the first bearing and the second bearing are located in the sealing cavity.

8. A downhole speed reducer according to claim 7, characterized in that: The housing includes a first shell, a second shell and a third shell connected in sequence, the first bearing is arranged on the inner wall of the first shell, the planetary gear reduction mechanism is located in the second shell, and the second bearing is arranged on the inner wall of the third shell.

9. The downhole reducer according to claim 1, characterized in that: The planetary gear reduction mechanism includes a driving wheel, three planetary wheels and a ring gear. The middle part of the input shaft is connected to the driving wheel, and the three planetary wheels are evenly distributed on the outer circumference of the driving wheel. The ring gear is sleeved on the outer circumference of the three planetary gears. The driving wheel is meshed with the three planetary wheels, and the three planetary wheels are all meshed with the ring gear. The middle parts of the three planetary wheels are rotatably connected to the output shaft, and the ring gear is arranged on the inner wall of the housing.

10. The downhole reducer according to claim 1, characterized in that: An oil filling hole is provided on the shell, and the oil filling hole is communicated with the sealing cavity.

Images