Transmission shaft assembly and drilling tool

Abstract

The invention discloses a transmission shaft assembly and a drilling tool, and relates to the technical field of drilling tools, the transmission shaft assembly comprises a transmission shaft, a transmission shaft shell, an upper bearing string and a lower bearing string, the lower end of the transmission shaft is used for being connected with a drill bit, the transmission shaft shell is arranged on the periphery of the transmission shaft in a sleeving mode, and the upper end of the transmission shaft shell is connected with a universal shaft shell; the transmission shaft is sleeved with the upper bearing string and the lower bearing string at intervals, inner rings of the upper bearing string and the lower bearing string are both connected with the periphery of the transmission shaft, and outer rings of the upper bearing string and the lower bearing string are both connected with the transmission shaft shell. According to the transmission shaft assembly, the double-string bearing formed by the upper-string bearing and the lower-string bearing evenly divides axial force, the axial force borne by the end face of each pair of string bearing is greatly reduced, and the service life of the transmission shaft assembly is greatly prolonged.

Description

Technical Field

[0001] This invention relates to the field of drilling tools, and in particular to a drive shaft assembly and a drilling tool. Background Technology

[0002] In oil and gas extraction, screw drills are increasingly widely used. A screw drill mainly consists of a motor assembly, a universal joint housing, a universal joint assembly, and a drive shaft assembly. The drive shaft assembly is the power output, driving the drill bit to break rocks. Therefore, the drive shaft assembly is a crucial component of the screw drill, and its structure and performance directly affect the drilling efficiency and service life of the screw drill.

[0003] Currently, most drive shaft assemblies use tandem bearings to bear axial loads. During operation, the end face of the tandem bearing bears the maximum axial force, which can easily cause end face failure and shorten the service life. Summary of the Invention

[0004] This invention provides a drive shaft assembly and a drilling tool to solve the technical problems of easy failure and short service life of existing drive shaft assemblies in related technologies.

[0005] In a first aspect, embodiments of the present invention provide a drive shaft assembly, the drive shaft assembly comprising: A drive shaft, the lower end of which is used to connect to a drill bit; A drive shaft housing, which is sleeved on the outer periphery of the drive shaft, and the upper end of the drive shaft housing is connected to the universal joint housing; An upper and lower tandem bearing are spaced apart on the drive shaft. The inner rings of both the upper and lower tandem bearings are connected to the outer circumference of the drive shaft, and the outer rings of both the upper and lower tandem bearings are connected to the drive shaft housing.

[0006] In some embodiments, the following are included: A water cap is fitted onto the drive shaft at the end away from the drill bit, and the water cap and the drive shaft are threaded together.

[0007] In some embodiments, it also includes: The upper TC moving sleeve and the shaft adjusting sleeve are sequentially disposed between the upper inner ring of the upper bearing and the water cap, and are both sleeved on the transmission shaft. The upper TC stationary sleeve and the housing adjustment sleeve are sequentially disposed between the upper outer ring of the upper bearing and the universal joint housing, and the upper TC stationary sleeve is fixedly connected to the drive shaft housing.

[0008] In some embodiments, it also includes: The lower TC moving sleeve is located on the lower side of the inner ring of the lower cascade bearing and is fixedly connected to the drive shaft; The lower TC stationary sleeve is fitted around the outer periphery of the lower TC moving sleeve and is fixedly connected to the lower end of the drive shaft housing.

[0009] In some embodiments, the following are sequentially provided between the lower TC moving sleeve and the inner ring of the lower cascade bearing: A semi-ring, wherein the semi-ring is sleeved outside the annular groove of the drive shaft, and the outer circumference of the semi-ring is provided with an upper keyway; A key, which is nested within the upper keyway; A retaining sleeve is provided between the inner ring of the lower spool bearing and the half ring, and a lower keyway is provided at one end of the retaining sleeve near the half ring, with the key extending into the lower keyway.

[0010] In some embodiments, A spacer is provided between the lower TC stationary sleeve and the lower ring of the lower tandem bearing.

[0011] In some embodiments, the drive shaft housing includes: Shell body; An annular boss is provided on the inner wall of the shell body, and the two sides of the annular boss are respectively attached to the outer ring of the upper bearing and the outer ring of the lower bearing.

[0012] In some embodiments, it also includes: A bearing adjusting sleeve is fitted between the drive shaft and the annular boss.

[0013] In some embodiments, the inner diameter of the lower bearing is not less than the inner diameter of the upper bearing.

[0014] Secondly, embodiments of the present invention also provide a drilling tool, including the aforementioned drive shaft assembly.

[0015] The beneficial effects of the technical solution provided by this invention include: This invention provides a drive shaft assembly and a drill bit. The drive shaft assembly includes a drive shaft, a drive shaft housing, an upper tandem bearing, and a lower tandem bearing. The lower end of the drive shaft is used to connect to the drill bit. The drive shaft housing is sleeved on the outer circumference of the drive shaft, and the upper end of the drive shaft housing is connected to a universal joint housing. The upper tandem bearing and the lower tandem bearing are spaced apart and sleeved on the drive shaft. The inner rings of both the upper and lower tandem bearings are connected to the outer circumference of the drive shaft, and the outer rings of both the upper and lower tandem bearings are connected to the drive shaft housing. In this invention, the double tandem bearings formed by the upper and lower tandem bearings evenly distribute the axial force, significantly reducing the axial force borne at the end face of each tandem bearing and greatly improving the service life of the drive shaft assembly. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a drive shaft assembly provided in an embodiment of the present invention; Figure label: 1. Drive shaft; 11. Annular groove; 2. Drive shaft housing; 21. Housing body; 22. Annular boss; 3. Upper bearing; 4. Lower cascade bearing; 5. Drill bit; 6. Universal joint housing; 7. Water cap; 81. Upper TC moving sleeve; 82. Shaft adjusting sleeve; 83. Upper TC stationary sleeve; 84. Housing adjusting sleeve; 85. Lower TC moving sleeve; 86. Lower TC stationary sleeve; 91. Half ring; 911. Upper keyway; 92. Key; 93. Retaining sleeve; 931. Lower keyway; 94. Spacer; 95. Bearing adjusting sleeve. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0019] This invention provides a drive shaft assembly and a drilling tool that can solve the technical problems of easy failure and short service life of existing drive shaft assemblies in related technologies.

[0020] See Figure 1 As shown in the figure, an embodiment of the present invention provides a drive shaft assembly, including a drive shaft 1, a drive shaft housing 2, an upper tandem bearing 3, and a lower tandem bearing 4. The lower end of the drive shaft 1 is used to connect to a drill bit 5. The drive shaft housing 2 is sleeved on the outer periphery of the drive shaft 1, and the upper end of the drive shaft housing 2 is connected to a universal joint housing 6. The upper tandem bearing 3 and the lower tandem bearing 4 are spaced apart and sleeved on the drive shaft 1. The inner rings of both the upper tandem bearing 3 and the lower tandem bearing 4 are connected to the outer periphery of the drive shaft 1, and the outer rings of both the upper tandem bearing 3 and the lower tandem bearing 4 are connected to the drive shaft housing 2. In this embodiment of the present invention, the double tandem bearings formed by the upper tandem bearing 3 and the lower tandem bearing 4 evenly distribute the axial force, significantly reducing the axial force borne at the end face of each tandem bearing, and greatly improving the service life of the drive shaft assembly.

[0021] This invention provides a drive shaft assembly comprising a drive shaft, a drive shaft housing, an upper tandem bearing, and a lower tandem bearing. The lower end of the drive shaft is used to connect to a drill bit. The drive shaft housing is sleeved around the outer circumference of the drive shaft, and the upper end of the drive shaft housing is connected to a universal joint housing. The upper and lower tandem bearings are spaced apart and sleeved on the drive shaft. The inner rings of both the upper and lower tandem bearings are connected to the outer circumference of the drive shaft, and the outer rings of both the upper and lower tandem bearings are connected to the drive shaft housing. In this invention, the double tandem bearings formed by the upper and lower tandem bearings evenly distribute the axial force, significantly reducing the axial force borne at the end face of each tandem bearing and greatly improving the service life of the drive shaft assembly.

[0022] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, the drive shaft assembly includes a water cap 7, which is sleeved on the drive shaft 1 at the end away from the drill bit 5, and the water cap 7 and the drive shaft 1 are threaded together. In this embodiment of the invention, the water cap 7 seals the upper end of the drive shaft 1, effectively preventing external contaminants such as drilling fluid and rock cuttings from entering the bearing cavity. At the same time, the lubricant inside the water cap 7 ensures continuous lubrication, reduces frictional heat and wear, thereby significantly extending the service life of the drive shaft assembly and improving reliability.

[0023] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1As shown, the drive shaft assembly further includes an upper TC moving sleeve 81, a shaft adjusting sleeve 82, an upper TC stationary sleeve 83, and a housing adjusting sleeve 84. The upper TC moving sleeve 81 and the shaft adjusting sleeve 82 are sequentially disposed between the upper inner ring of the upper tandem bearing 3 and the water cap 7, and are both sleeved on the drive shaft 1. The upper TC stationary sleeve 83 and the housing adjusting sleeve 84 are sequentially disposed between the upper outer ring of the upper tandem bearing 3 and the universal joint housing 6. The upper TC stationary sleeve 83 is fixedly connected to the drive shaft housing 2. In this embodiment of the invention, the upper TC moving sleeve 81 rotates synchronously with the drive shaft 1. Through the sliding fit with the upper TC stationary sleeve 83, part of the axial load is transferred to the drive shaft housing 2, reducing the force on the upper tandem bearing 3. The shaft adjusting sleeve 82 optimizes the axial preload of the upper TC moving sleeve 81 through thickness adjustment. The upper TC stationary sleeve 83 is fixed to the drive shaft housing 2, forming a stable thrust bearing pair with the upper TC moving sleeve 81, making the load distribution of the double tandem bearings more balanced, significantly improving reliability and service life.

[0024] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, the drive shaft assembly further includes a lower TC moving sleeve 85 and a lower TC stationary sleeve 86. The lower TC moving sleeve 85 is located on the lower side of the inner ring of the lower tandem bearing 4 and is fixedly connected to the drive shaft 1. The lower TC stationary sleeve 86 is sleeved on the outer periphery of the lower TC moving sleeve 85 and is fixedly connected to the lower end of the drive shaft housing 2. In this embodiment of the invention, the lower TC moving sleeve 85 rotates synchronously with the drive shaft 1, transmitting drilling pressure to the lower tandem bearing 4 through a rigid connection. The lower TC stationary sleeve 86, fixed to the drive shaft housing 2, forms a stationary bearing surface. The two work together to effectively share the axial load and reduce end face wear. By diverting the load, the service life of the lower tandem bearing 4 is extended. At the same time, it facilitates quick replacement after wear, significantly improving the reliability of the drive shaft assembly in high-pressure mud environments.

[0025] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1As shown, a semi-ring 91, a key 92, and a retaining sleeve 93 are sequentially provided between the lower TC moving sleeve 85 and the inner ring of the lower tandem bearing 4. The semi-ring 91 is sleeved outside the annular groove 11 of the transmission shaft 1. An upper keyway 911 is provided on the outer periphery of the semi-ring 91. The key 92 is nested in the upper keyway 911. The retaining sleeve 93 is provided between the inner ring of the lower tandem bearing 4 and the semi-ring 91. The end of the retaining sleeve 93 near the semi-ring 91 is provided with a lower keyway 931. The key 92 extends into the lower keyway 931. In this embodiment of the invention, the outer diameter of the semi-ring 91 is larger than the inner diameter of the lower TC stationary sleeve 86, which has the function of preventing the drive shaft at the mounting bearing from breaking and falling into the well; the key 92 is installed in the inner hole of the retaining sleeve 93 and between the outer circle of the semi-ring 91, which can prevent the semi-ring 91 from rotating relative to the drive shaft 1; the retaining sleeve 93 is installed on the step of the drive shaft 1 and is pressed by the thread of the lower TC moving sleeve 85 and the upper end of the drive shaft 1, which facilitates the installation of other parts. The semi-ring 91, key 92 and retaining sleeve 93 cooperate to form an axial limit, avoiding wear caused by relative rotation. The cooperation realizes the functions of axial positioning and torque transmission. The structure is compact and stable, which improves the reliability of the drive shaft assembly.

[0026] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, a spacer 94 is provided between the lower TC stationary sleeve 86 and the lower outer ring of the lower tandem bearing 4 for adjusting the preload of the tandem bearing. In this embodiment of the invention, by controlling the thickness of the spacer 94, it is possible to ensure that the preload of the drive shaft assembly is in the optimal working state, while ensuring uniform transmission of axial load, avoiding local stress concentration, thereby reducing the risk of fatigue damage and improving the load-bearing stability and service life of the drive shaft assembly.

[0027] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, the drive shaft housing 2 includes a housing body 21 and an annular boss 22. The annular boss 22 is disposed on the inner wall of the housing body 21, and its two sides respectively fit against the outer rings of the upper tandem bearing 3 and the lower tandem bearing 4. In this embodiment of the invention, the annular boss 22 enables the outer rings of the upper tandem bearing 3 and the lower tandem bearing 4 to simultaneously obtain axial support surfaces. The limiting effect of the end faces on both sides of the annular boss 22 ensures the parallel alignment and assembly of the upper tandem bearing 3 and the lower tandem bearing 4, effectively preventing wear. At the same time, as a force transmission medium, the annular boss 22 evenly distributes the drilling pressure borne by the drive shaft housing 2 to the outer rings of the upper tandem bearing 3 and the lower tandem bearing 4, avoiding overload of one bearing, improving the overall load-bearing efficiency and impact resistance, and realizing precise positioning and load distribution of the double tandem bearings.

[0028] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1As shown, the drive shaft assembly also includes a bearing adjusting sleeve 95, which is sleeved between the drive shaft 1 and the annular boss 22. In this embodiment of the invention, the adjustable bearing adjusting sleeve 95 sleeved between the drive shaft 1 and the annular boss 22 ensures that the bearing is in optimal working condition, significantly extending the maintenance cycle of critical components.

[0029] As an optional implementation, in one embodiment of the invention, the inner diameter of the lower cascade bearing 4 is not less than the inner diameter of the upper cascade bearing 3. In this embodiment of the invention, the inner diameter of the lower cascade bearing 4 is greater than or equal to the inner diameter of the upper cascade bearing 3. The lower cascade bearing 4 has a larger or equal inner diameter dimension, ensuring that its bearing area is not less than that of the upper cascade bearing. This allows for a more uniform distribution of stress when sharing axial loads, preventing premature failure of the lower bearing due to concentrated drilling pressure, and further ensuring the service life of the drive shaft assembly.

[0030] The present invention provides a drive shaft assembly, the assembly process of which is as follows: First, thread the lower TC moving sleeve 85 onto the drive shaft 1. Then, fit the lower TC stationary sleeve 86 onto the outer circumference of the lower TC moving sleeve 85. Install the semi-ring 91 into the annular groove 11 of the drive shaft 1 above the lower TC moving sleeve 85. Install the key 92 into the upper keyway 911 on the outer circumference of the semi-ring 91. Fit the retaining sleeve 93 onto the drive shaft 1, aligning the lower keyway 931 on the inner circumference of the retaining sleeve 93 with the key 92. Fit the spacer 94 onto the outer circumferences of the semi-ring 91 and the retaining sleeve 93. Fit the lower cascade bearing 4 onto the outer circumference of the drive shaft 1 and position it on the upper end face of the retaining sleeve 93. Finally, fit the drive shaft housing 2 onto the lower cascade bearing 4 and the spacer in sequence. The upper bearing 3 is fitted onto the outer circle of the drive shaft 1 and the lower TC stationary sleeve 86, and connected to the lower TC stationary sleeve 86 by threads. The bearing adjusting sleeve 95 is then installed on the outer circle of the drive shaft 1. The upper TC moving sleeve 81 is fitted onto the drive shaft 1, and the upper TC stationary sleeve 83 is fitted onto the outer circle of the upper TC moving sleeve 81. The shaft adjusting sleeve 82 is installed onto the drive shaft 1, and the water cap 7 is connected to the drive shaft 1 by threads. The housing adjusting sleeve 84 is fitted onto the outer circle of the shaft adjusting sleeve 82. Finally, the universal joint housing 6 is connected to the drive shaft housing 2 by threads to complete the assembly.

[0031] This invention also provides a drilling tool, which includes the aforementioned drive shaft assembly. The drive shaft assembly includes a drive shaft 1, a drive shaft housing 2, an upper tandem bearing 3, and a lower tandem bearing 4. The lower end of the drive shaft 1 is used to connect to a drill bit 5. The drive shaft housing 2 is sleeved on the outer periphery of the drive shaft 1, and the upper end of the drive shaft housing 2 is connected to a universal joint housing 6. The upper tandem bearing 3 and the lower tandem bearing 4 are spaced apart and sleeved on the drive shaft 1. The inner rings of both the upper tandem bearing 3 and the lower tandem bearing 4 are connected to the outer periphery of the drive shaft 1, and the outer rings of both the upper tandem bearing 3 and the lower tandem bearing 4 are connected to the drive shaft housing 2. In this invention, the double tandem bearings formed by the upper tandem bearing 3 and the lower tandem bearing 4 evenly distribute the axial force, significantly reducing the axial force borne at the end face of each tandem bearing and greatly improving the service life of the drilling tool.

[0032] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, the drive shaft assembly includes a water cap 7, which is sleeved on the drive shaft 1 at the end away from the drill bit 5, and the water cap 7 and the drive shaft 1 are threaded together. In this embodiment of the invention, the water cap 7 seals the upper end of the drive shaft 1, effectively preventing external contaminants such as drilling fluid and rock cuttings from entering the bearing cavity. At the same time, the lubricant inside the water cap 7 ensures continuous lubrication, reduces frictional heat and wear, thereby significantly extending the service life of the drill bit and improving reliability.

[0033] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, the drive shaft assembly further includes an upper TC moving sleeve 81, a shaft adjusting sleeve 82, an upper TC stationary sleeve 83, and a housing adjusting sleeve 84. The upper TC moving sleeve 81 and the shaft adjusting sleeve 82 are sequentially disposed between the upper inner ring of the upper tandem bearing 3 and the water cap 7, and are both sleeved on the drive shaft 1. The upper TC stationary sleeve 83 and the housing adjusting sleeve 84 are sequentially disposed between the upper outer ring of the upper tandem bearing 3 and the universal joint housing 6. The upper TC stationary sleeve 83 is fixedly connected to the drive shaft housing 2. In this embodiment of the invention, the upper TC moving sleeve 81 rotates synchronously with the drive shaft 1. Through the sliding fit with the upper TC stationary sleeve 83, part of the axial load is transferred to the drive shaft housing 2, reducing the force on the upper tandem bearing 3. The shaft adjusting sleeve 82 optimizes the axial preload of the upper TC moving sleeve 81 through thickness adjustment. The upper TC stationary sleeve 83 is fixed to the drive shaft housing 2, forming a stable thrust bearing pair with the upper TC moving sleeve 81, making the load distribution of the double tandem bearings more balanced, significantly improving reliability and service life.

[0034] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1As shown, the drive shaft assembly also includes a lower TC moving sleeve 85 and a lower TC stationary sleeve 86. The lower TC moving sleeve 85 is located on the lower side of the inner ring of the lower tandem bearing 4 and is fixedly connected to the drive shaft 1. The lower TC stationary sleeve 86 is sleeved on the outer periphery of the lower TC moving sleeve 85 and is fixedly connected to the lower end of the drive shaft housing 2. In this embodiment of the invention, the lower TC moving sleeve 85 rotates synchronously with the drive shaft 1, transmitting drilling pressure to the lower tandem bearing 4 through a rigid connection. The lower TC stationary sleeve 86, fixed to the drive shaft housing 2, forms a stationary bearing surface. The two work together to effectively share the axial load and reduce end face wear. By diverting the load, the service life of the lower tandem bearing 4 is extended, and it also facilitates quick replacement after wear, significantly improving the reliability of the drill bit in a high-pressure mud environment.

[0035] As an optional implementation, in one embodiment of the invention, see [link to relevant documentation]. Figure 1 As shown, a semi-ring 91, a key 92, and a retaining sleeve 93 are sequentially provided between the lower TC moving sleeve 85 and the inner ring of the lower tandem bearing 4. The semi-ring 91 is sleeved outside the annular groove 11 of the transmission shaft 1. An upper keyway 911 is provided on the outer periphery of the semi-ring 91. The key 92 is nested in the upper keyway 911. The retaining sleeve 93 is provided between the inner ring of the lower tandem bearing 4 and the semi-ring 91. The end of the retaining sleeve 93 near the semi-ring 91 is provided with a lower keyway 931. The key 92 extends into the lower keyway 931. In this embodiment of the invention, the outer diameter of the semi-ring 91 is larger than the inner diameter of the lower TC stationary sleeve 86, which has the function of preventing the drive shaft at the installation cascade bearing from breaking and falling into the well; the key 92 is installed in the inner hole of the retaining sleeve 93 and between the outer circle of the semi-ring 91, which can prevent the semi-ring 91 from rotating relative to the drive shaft 1; the retaining sleeve 93 is installed on the step of the drive shaft 1 and is pressed by the thread of the lower TC moving sleeve 85 and the upper end of the drive shaft 1, which facilitates the installation of other parts. The semi-ring 91, key 92 and retaining sleeve 93 cooperate to form an axial limit, avoiding wear caused by relative rotation. The cooperation realizes the functions of axial positioning and torque transmission. The structure is compact and stable, improving the reliability of the drilling tool.

[0036] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0037] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0038] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement 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 present 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 of the invention herein.

Claims

1. A drive shaft assembly, characterized in that, include: Drive shaft (1), the lower end of which is used to connect to drill bit (5); A drive shaft housing (2) is fitted around the outer periphery of the drive shaft (1), and the upper end of the drive shaft housing (2) is connected to the universal joint housing (6). An upper spool bearing (3) and a lower spool bearing (4) are spaced apart on the drive shaft (1). The inner rings of the upper spool bearing (3) and the lower spool bearing (4) are connected to the outer circumference of the drive shaft (1), and the outer rings of the upper spool bearing (3) and the lower spool bearing (4) are connected to the drive shaft housing (2).

2. The drive shaft assembly according to claim 1, characterized in that, include: Water cap (7) is sleeved on the drive shaft (1) at one end away from the drill bit (5), and the water cap (7) and the drive shaft (1) are threaded together.

3. A drive shaft assembly according to claim 2, characterized in that, Also includes: Upper TC moving sleeve (81) and shaft adjusting sleeve (82) are arranged sequentially between the upper inner ring of the upper string bearing (3) and the water cap (7) and are both sleeved on the transmission shaft (1). The upper TC stationary sleeve (83) and the housing adjustment sleeve (84) are arranged sequentially between the upper ring of the upper bearing (3) and the universal joint housing (6). The upper TC stationary sleeve (83) is fixedly connected to the transmission shaft housing (2).

4. A drive shaft assembly according to claim 1, characterized in that, Also includes: The lower TC moving sleeve (85) is located on the lower side of the inner ring of the lower tandem bearing (4) and is fixedly connected to the transmission shaft (1). The lower TC stationary sleeve (86) is sleeved on the outer periphery of the lower TC moving sleeve (85) and fixedly connected to the lower end of the transmission shaft housing (2).

5. A drive shaft assembly according to claim 4, characterized in that, Between the inner ring of the lower TC moving sleeve (85) and the lower cascade bearing (4), there are sequentially arranged: A semi-ring (91) is sleeved on the annular groove (11) of the transmission shaft (1), and an upper keyway (911) is provided on the outer periphery of the semi-ring (91). Key (92), the key (92) is nested within the upper keyway (911); A retainer (93) is provided between the inner ring of the lower bearing (4) and the half ring (91), and a lower keyway (931) is provided at one end of the retainer (93) near the half ring (91), and the key (92) extends into the lower keyway (931).

6. A drive shaft assembly according to claim 4, characterized in that: A spacer (94) is provided between the lower TC stationary sleeve (86) and the lower ring of the lower tandem bearing (4).

7. A drive shaft assembly according to claim 1, characterized in that, The drive shaft housing (2) includes: Shell body (21); An annular boss (22) is provided on the inner wall of the shell body (21), and the two sides of the annular boss (22) are respectively attached to the outer ring of the upper bearing (3) and the outer ring of the lower bearing (4).

8. A drive shaft assembly according to claim 7, characterized in that, Also includes: Bearing adjusting sleeve (95) is sleeved between the drive shaft (1) and the annular boss (22).

9. A drive shaft assembly according to claim 1, characterized in that: The inner diameter of the lower bearing (4) is not less than the inner diameter of the upper bearing (3).

10. A drilling tool, characterized in that, Includes a drive shaft assembly as described in any one of claims 1-9.

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