阅读说明：本技术 低摩擦力的花键传动结构及采用该结构的水力振荡器 (Low-friction spline transmission structure and hydraulic oscillator adopting same ) 是由 余长柏 钱伟强 蒋洪亮 代琼曦 涂辉 黎爱军 类歆 于 2020-06-12 设计创作，主要内容包括：本发明提供一种低摩擦力的花键传动结构及采用该结构的水力振荡器,它包括花键轴和花键滑套,在花键轴和花键滑套的中心均设有通孔,花键轴的外壁设有多个外齿,在花键滑套的内壁设有与外齿相啮合的多个内齿,在内齿与外齿的侧面之间设有多个滚针或滚珠。能够大幅减少花键轴与花键滑套之间的摩擦力,减少工具无效压耗。本发明的水力振荡器,通过采用上述的花键传动结构,在同等压力介质条件下,振幅提高约7%,频率提高约8.5%。通过采用多个滚针或滚珠的结构,还能够进一步改善花键连接结构的接触面积,大幅改善传递扭矩工况下的受力结构,减少表面撕裂现象。(The invention provides a spline transmission structure with low friction force and a hydraulic oscillator adopting the structure, which comprises a spline shaft and a spline sliding sleeve, wherein through holes are formed in the centers of the spline shaft and the spline sliding sleeve, a plurality of external teeth are arranged on the outer wall of the spline shaft, a plurality of internal teeth meshed with the external teeth are arranged on the inner wall of the spline sliding sleeve, and a plurality of rolling needles or rolling balls are arranged between the side faces of the internal teeth and the external teeth. The friction between the spline shaft and the spline sliding sleeve can be greatly reduced, and the invalid pressure loss of tools is reduced. By adopting the spline transmission structure, the amplitude of the hydraulic oscillator is improved by about 7 percent and the frequency of the hydraulic oscillator is improved by about 8.5 percent under the condition of the same pressure medium. Through the structure that adopts a plurality of kingpins or ball, can also further improve the area of contact of spline connection structure, improve the atress structure under the transmission moment of torsion operating mode by a wide margin, reduce the surface and tear the phenomenon.)

1. The utility model provides a spline transmission structure of low friction, it includes integral key shaft (2) and spline sliding sleeve (1), all is equipped with the through-hole at the center of integral key shaft (2) and spline sliding sleeve (1), and the outer wall of integral key shaft (2) is equipped with a plurality of external teeth (28), is equipped with a plurality of internal teeth (11) that mesh mutually with external teeth (28) at the inner wall of spline sliding sleeve (1), characterized by: a plurality of needle rollers (6) or balls are provided between the side surfaces of the internal teeth (11) and the external teeth (28).

2. A low friction spline drive according to claim 1, wherein: the meshing length between the external teeth (28) and the internal teeth (11) is greater than or equal to 10cm, the torque reaching 10000 N.m is transmitted between the spline shaft (2) and the spline sliding sleeve (1), the spline shaft moves along the axial direction relatively, and the vibration frequency of the axial movement reaches 9-26 Hz; the relative axial movement stroke is 0.3-1 cm.

3. A low friction spline drive according to claim 1, wherein: the side surfaces of the internal teeth (11) and the external teeth (28) are provided with arc-shaped or V-shaped grooves, and the balls are arranged in the grooves.

4. A low friction spline drive according to claim 3, wherein: the grooves are arranged in a plurality along the tooth tops to the tooth bottoms of the internal teeth (11) and the external teeth (28).

5. A low friction spline drive construction according to claim 3 or 4, wherein: limiting structures are arranged at two ends of a groove of the internal tooth (11) or the external tooth (28), and the length of the groove is smaller than the meshing length between the external tooth (28) and the internal tooth (11).

6. A low friction spline drive according to claim 1, wherein: a sliding retainer (21) is arranged at the tooth top of the external teeth (28), and a plurality of first limiting end heads (22) are arranged on the two side edges of the retainer (21) along the length direction; the retainer (21) is also provided with a plurality of connecting columns (24) along the edges of two sides in the length direction, the connecting columns (24) extend towards the direction far away from the first limiting end (22) and are fixedly connected with a lower limiting plate (25), and the lower limiting plate (25) is provided with a plurality of second limiting ends (26) corresponding to the first limiting end (22);

the roller pin (6) is positioned between the first limit end (22) and the second limit end (26), a groove is formed in the end of the roller pin (6), and the first limit end (22) and the second limit end (26) are partially positioned in the groove; so that the needle roller (6) rolls along the axial direction of the spline shaft (2) and is limited.

7. A low friction spline drive according to claim 1, wherein: a sliding retainer (21) is arranged at the tooth top of the outer teeth (28), a plurality of connecting columns (24) are arranged on the edges of two sides of the retainer (21) along the length direction, the connecting columns (24) extend in the direction away from the retainer (21) and are fixedly connected with a lower limiting plate (25), and a plurality of limiting grooves (28) are arranged on the edges of the retainer (21) and the lower limiting plate (25); the end of the roller pin (6) is rotatably positioned in the limiting groove (28) so that the roller pin (6) rolls along the axial direction of the spline shaft (2) and is limited.

8. A low friction spline drive construction according to claim 6 or 7, wherein:

the diameter of the roller pin (6) is 1-6 mm;

the diameter of the ball (7) is 1-6 mm.

9. A low friction spline drive construction according to claim 6 or 7, wherein: the spline shaft (2) and the spline sliding sleeve (1) are provided with steps to limit the stroke of the retainer (21).

10. A hydraulic oscillator using the spline connection structure according to any one of claims 1 to 9, characterized in that: the spline sliding sleeve (1) is fixedly connected with the vibration joint (8);

the vibration joint (8) comprises a screw motor, a screw in the screw motor is connected with the moving plate and drives the moving plate to rotate so as to enable the size of the through-flow section of the hole in the moving plate and the size of the through-flow section of the hole in the vibration joint (8) to change in a reciprocating mode;

or the vibration joint (8) comprises a turbine, a shaft of the turbine is connected with the moving plate and drives the moving plate to rotate so as to enable the sizes of through-flow sections of the holes in the moving plate and the holes in the vibration joint (8) to change in a reciprocating mode;

or the vibration joint (8) is a vortex vibration joint, a vortex cavity and an overflowing hole positioned in the vortex cavity are arranged in the vortex vibration joint, so that the liquid medium generates vibration in the vortex cavity.

Technical Field

The invention relates to the field of petroleum drilling and production auxiliary equipment, in particular to a spline transmission structure with low friction and a hydraulic oscillator adopting the structure.

Background

In the field of petroleum and natural gas production, a hydraulic oscillator is a tool for improving the rapid drilling of a horizontal well, and the static friction between a drill string and a well wall is converted into sliding friction through the vibration of the hydraulic oscillator so as to reduce the friction resistance. For example, chinese patent document CN106917586A describes a screw type downhole hydraulic oscillator, which generates a pressure pulse by a screw motor and vibrates a vibration nipple. CN108442883A has also been described in a similar structure, and CN106930688A a vortex type hydraulic pulse axial impact tool also has been described in a structure that uses a vortex chamber to generate vibration. The hydraulic oscillator needs to generate axial vibration while transmitting torque, namely, at least two components have relative axial reciprocating motion, and the axial vibration is usually realized by a spline connection structure, in the prior art, a spline transmission structure with low friction needs to transmit torque of more than 10000N/m, and the vibration frequency reaches 9-26 Hz. The structures of ball spline pairs are also described in chinese patent documents 201410481881.3 and 201310754921.2, but in this document, the rolling elements, i.e. the rolling elements, are also load transmitting elements, i.e. the elements are subjected to shear forces during rolling, which increases the structural burden, and the accuracy requirements are very high, which causes the tooth grooves or the rolling elements to wear out quickly, and does not have the effect of extending the service life of the entire structure.

Disclosure of Invention

The invention aims to provide a spline transmission structure with low friction, which can greatly reduce the friction resistance of the spline connection structure and prolong the service life of the spline connection structure.

The invention aims to solve another technical problem of providing a hydraulic oscillator which has a longer service life under the working conditions of large torque and axial vibration.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: the utility model provides a spline transmission structure of low friction, it includes integral key shaft and spline sliding sleeve, all is equipped with the through-hole at integral key shaft and spline sliding sleeve's center, and the outer wall of integral key shaft is equipped with a plurality of external teeth, is equipped with a plurality of internal teeth that mesh with the external tooth at spline sliding sleeve's inner wall, is equipped with a plurality of kingpins or ball between the side of internal tooth and external tooth.

In the preferred scheme, the meshing length between the external teeth and the internal teeth is more than or equal to 10cm, the torque reaching 10000 N.m is transmitted between the spline shaft and the spline sliding sleeve and moves along the axial direction relatively, and the vibration frequency of the axial movement reaches 9-26 Hz; the relative axial movement stroke is 0.3-1 cm.

In a preferred scheme, arc-shaped or V-shaped grooves are formed in the side faces of the inner teeth and the outer teeth, and the balls are arranged in the grooves.

In a preferred embodiment, the grooves are provided in plurality along the tooth crest to the tooth bottom of the internal teeth and the external teeth.

In a preferred scheme, limiting structures are arranged at two ends of a groove of the inner tooth or the outer tooth, and the length of the groove is smaller than the meshing length between the outer tooth and the inner tooth.

In the preferred scheme, a sliding retainer is arranged at the tooth top of the outer tooth, and a plurality of first limiting end heads are arranged on the two side edges of the retainer along the length direction; the edges of two sides of the retainer along the length direction are also provided with a plurality of connecting columns, the connecting columns extend towards the direction far away from the first limiting end and are fixedly connected with the lower limiting plate, and the lower limiting plate is provided with a plurality of second limiting ends corresponding to the first limiting ends;

the roller pin is positioned between the first limit end and the second limit end, the end of the roller pin is provided with a groove, and the first limit end and the second limit end are positioned in the groove; so that the rolling needles roll along the axial direction of the spline shaft and are limited.

In the preferred scheme, a sliding retainer is arranged at the tooth top of the outer tooth, a plurality of connecting columns are arranged on the two side edges of the retainer along the length direction, the connecting columns extend towards the direction far away from the retainer and are fixedly connected with a lower limiting plate, and a plurality of limiting grooves are arranged on the edge of the retainer and the lower limiting plate; the end of the roller pin can be rotatably positioned in the limiting groove, so that the roller pin rolls along the axial direction of the spline shaft and is limited.

In the preferred scheme, the diameter of the roller pin is 1-6 mm; the diameter of the ball is 1-6 mm.

In the preferred scheme, steps are arranged on the spline shaft and the spline sliding sleeve so as to limit the stroke of the retainer.

The spline sliding sleeve is fixedly connected with the vibration joint;

the vibration joint comprises a screw motor, a screw in the screw motor is connected with the moving plate and drives the moving plate to rotate so as to enable the size of the through-flow section of the hole in the moving plate and the size of the through-flow section of the hole in the vibration joint to change in a reciprocating mode;

or the vibration joint comprises a turbine, a shaft of the turbine is connected with the moving plate and drives the moving plate to rotate, so that the sizes of through-flow sections of the holes in the moving plate and the holes in the vibration joint are changed in a reciprocating mode;

or the vibration node is a vortex vibration node, a vortex cavity and an overflowing hole positioned in the vortex cavity are arranged in the vortex vibration node, so that the liquid medium generates vibration in the vortex cavity.

The spline transmission structure with low friction provided by the invention can greatly reduce the friction between the spline shaft and the spline sliding sleeve, particularly the friction under the working conditions of 10000N/m large torque and 9-26 Hz high-frequency reciprocating motion, and reduce the tool pressure consumption. By adopting the spline transmission structure, the amplitude of the hydraulic oscillator is improved by about 7 percent and the frequency of the hydraulic oscillator is improved by about 8.5 percent under the condition of the same pressure medium. In the preferred scheme, through adopting the structure of a plurality of kingpins or balls, can also further improve the area of contact of spline connection structure, improve the atress structure under the transmission moment of torsion operating mode by a wide margin, reduce the surface and tear the phenomenon.

Drawings

The invention is further illustrated by the following examples in conjunction with the accompanying drawings:

FIG. 1 is a schematic diagram of the oscillating section structure of a hydraulic oscillator using a spline connection structure according to the present invention.

FIG. 2 is a schematic sectional view taken along line A-A in FIG. 1.

Fig. 3 is a partially enlarged schematic view of a portion B in fig. 2.

Fig. 4 is a partial view of fig. 3 taken along direction C.

Fig. 5 is a perspective view of the cage of the present invention.

Fig. 6 is a partially enlarged schematic view of a preferred embodiment at B in fig. 2.

Fig. 7 is a partial view taken along line D in fig. 6.

Fig. 8 is a schematic sectional view a-a of another alternative to fig. 1.

FIG. 9 is a schematic cross-sectional view of the prior art A-A in the figure.

FIG. 10 is a schematic view of a prior art external tooth after tooth flank tearing.

FIG. 11 is a graph comparing amplitude and frequency for an equivalent pressure medium of the present invention and the prior art.

In the figure: the spline shaft comprises a spline shaft 1, internal teeth 11, a spline sliding sleeve 2, a tooth surface 201, a retainer 21, a first limit end 22, an end groove 23, a connecting column 24, a lower limit plate 25, a second limit end 26, external teeth 27, a limit groove 28, a pressure pulse medium 3, a disc spring 4, a piston 5, a roller pin 6, a ball 7 and a vibration joint 8.

Detailed Description